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-rw-r--r--drivers/memory/atmel-ebi.c11
-rw-r--r--drivers/memory/brcmstb_dpfe.c164
-rw-r--r--drivers/memory/emif.c5
-rw-r--r--drivers/memory/jedec_ddr.h61
-rw-r--r--drivers/memory/mtk-smi.c4
-rw-r--r--drivers/memory/of_memory.c149
-rw-r--r--drivers/memory/of_memory.h18
-rw-r--r--drivers/memory/samsung/Kconfig13
-rw-r--r--drivers/memory/samsung/Makefile1
-rw-r--r--drivers/memory/samsung/exynos5422-dmc.c1550
10 files changed, 1903 insertions, 73 deletions
diff --git a/drivers/memory/atmel-ebi.c b/drivers/memory/atmel-ebi.c
index 0322df9dc249..14386d0b5f57 100644
--- a/drivers/memory/atmel-ebi.c
+++ b/drivers/memory/atmel-ebi.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* EBI driver for Atmel chips
* inspired by the fsl weim bus driver
*
* Copyright (C) 2013 Jean-Jacques Hiblot <jjhiblot@traphandler.com>
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
*/
#include <linux/clk.h>
@@ -19,6 +16,8 @@
#include <linux/regmap.h>
#include <soc/at91/atmel-sfr.h>
+#define AT91_EBI_NUM_CS 8
+
struct atmel_ebi_dev_config {
int cs;
struct atmel_smc_cs_conf smcconf;
@@ -314,7 +313,7 @@ static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
if (ret)
return ret;
- if (cs >= AT91_MATRIX_EBI_NUM_CS ||
+ if (cs >= AT91_EBI_NUM_CS ||
!(ebi->caps->available_cs & BIT(cs))) {
dev_err(dev, "invalid reg property in %pOF\n", np);
return -EINVAL;
@@ -344,7 +343,7 @@ static int atmel_ebi_dev_setup(struct atmel_ebi *ebi, struct device_node *np,
apply = true;
i = 0;
- for_each_set_bit(cs, &cslines, AT91_MATRIX_EBI_NUM_CS) {
+ for_each_set_bit(cs, &cslines, AT91_EBI_NUM_CS) {
ebid->configs[i].cs = cs;
if (apply) {
diff --git a/drivers/memory/brcmstb_dpfe.c b/drivers/memory/brcmstb_dpfe.c
index 6827ed484750..82b415be18d1 100644
--- a/drivers/memory/brcmstb_dpfe.c
+++ b/drivers/memory/brcmstb_dpfe.c
@@ -127,7 +127,6 @@ enum dpfe_msg_fields {
MSG_COMMAND,
MSG_ARG_COUNT,
MSG_ARG0,
- MSG_CHKSUM,
MSG_FIELD_MAX = 16 /* Max number of arguments */
};
@@ -180,7 +179,7 @@ struct dpfe_api {
};
/* Things we need for as long as we are active. */
-struct private_data {
+struct brcmstb_dpfe_priv {
void __iomem *regs;
void __iomem *dmem;
void __iomem *imem;
@@ -232,9 +231,13 @@ static struct attribute *dpfe_v3_attrs[] = {
};
ATTRIBUTE_GROUPS(dpfe_v3);
-/* API v2 firmware commands */
-static const struct dpfe_api dpfe_api_v2 = {
- .version = 2,
+/*
+ * Old API v2 firmware commands, as defined in the rev 0.61 specification, we
+ * use a version set to 1 to denote that it is not compatible with the new API
+ * v2 and onwards.
+ */
+static const struct dpfe_api dpfe_api_old_v2 = {
+ .version = 1,
.fw_name = "dpfe.bin",
.sysfs_attrs = dpfe_v2_groups,
.command = {
@@ -243,21 +246,42 @@ static const struct dpfe_api dpfe_api_v2 = {
[MSG_COMMAND] = 1,
[MSG_ARG_COUNT] = 1,
[MSG_ARG0] = 1,
- [MSG_CHKSUM] = 4,
},
[DPFE_CMD_GET_REFRESH] = {
[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
[MSG_COMMAND] = 2,
[MSG_ARG_COUNT] = 1,
[MSG_ARG0] = 1,
- [MSG_CHKSUM] = 5,
},
[DPFE_CMD_GET_VENDOR] = {
[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
[MSG_COMMAND] = 2,
[MSG_ARG_COUNT] = 1,
[MSG_ARG0] = 2,
- [MSG_CHKSUM] = 6,
+ },
+ }
+};
+
+/*
+ * API v2 firmware commands, as defined in the rev 0.8 specification, named new
+ * v2 here
+ */
+static const struct dpfe_api dpfe_api_new_v2 = {
+ .version = 2,
+ .fw_name = NULL, /* We expect the firmware to have been downloaded! */
+ .sysfs_attrs = dpfe_v2_groups,
+ .command = {
+ [DPFE_CMD_GET_INFO] = {
+ [MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
+ [MSG_COMMAND] = 0x101,
+ },
+ [DPFE_CMD_GET_REFRESH] = {
+ [MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
+ [MSG_COMMAND] = 0x201,
+ },
+ [DPFE_CMD_GET_VENDOR] = {
+ [MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
+ [MSG_COMMAND] = 0x202,
},
}
};
@@ -273,49 +297,51 @@ static const struct dpfe_api dpfe_api_v3 = {
[MSG_COMMAND] = 0x0101,
[MSG_ARG_COUNT] = 1,
[MSG_ARG0] = 1,
- [MSG_CHKSUM] = 0x104,
},
[DPFE_CMD_GET_REFRESH] = {
[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
[MSG_COMMAND] = 0x0202,
[MSG_ARG_COUNT] = 0,
- /*
- * This is a bit ugly. Without arguments, the checksum
- * follows right after the argument count and not at
- * offset MSG_CHKSUM.
- */
- [MSG_ARG0] = 0x203,
},
/* There's no GET_VENDOR command in API v3. */
},
};
-static bool is_dcpu_enabled(void __iomem *regs)
+static bool is_dcpu_enabled(struct brcmstb_dpfe_priv *priv)
{
u32 val;
- val = readl_relaxed(regs + REG_DCPU_RESET);
+ mutex_lock(&priv->lock);
+ val = readl_relaxed(priv->regs + REG_DCPU_RESET);
+ mutex_unlock(&priv->lock);
return !(val & DCPU_RESET_MASK);
}
-static void __disable_dcpu(void __iomem *regs)
+static void __disable_dcpu(struct brcmstb_dpfe_priv *priv)
{
u32 val;
- if (!is_dcpu_enabled(regs))
+ if (!is_dcpu_enabled(priv))
return;
+ mutex_lock(&priv->lock);
+
/* Put DCPU in reset if it's running. */
- val = readl_relaxed(regs + REG_DCPU_RESET);
+ val = readl_relaxed(priv->regs + REG_DCPU_RESET);
val |= (1 << DCPU_RESET_SHIFT);
- writel_relaxed(val, regs + REG_DCPU_RESET);
+ writel_relaxed(val, priv->regs + REG_DCPU_RESET);
+
+ mutex_unlock(&priv->lock);
}
-static void __enable_dcpu(void __iomem *regs)
+static void __enable_dcpu(struct brcmstb_dpfe_priv *priv)
{
+ void __iomem *regs = priv->regs;
u32 val;
+ mutex_lock(&priv->lock);
+
/* Clear mailbox registers. */
writel_relaxed(0, regs + REG_TO_DCPU_MBOX);
writel_relaxed(0, regs + REG_TO_HOST_MBOX);
@@ -329,6 +355,8 @@ static void __enable_dcpu(void __iomem *regs)
val = readl_relaxed(regs + REG_DCPU_RESET);
val &= ~(1 << DCPU_RESET_SHIFT);
writel_relaxed(val, regs + REG_DCPU_RESET);
+
+ mutex_unlock(&priv->lock);
}
static unsigned int get_msg_chksum(const u32 msg[], unsigned int max)
@@ -343,7 +371,7 @@ static unsigned int get_msg_chksum(const u32 msg[], unsigned int max)
return sum;
}
-static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
+static void __iomem *get_msg_ptr(struct brcmstb_dpfe_priv *priv, u32 response,
char *buf, ssize_t *size)
{
unsigned int msg_type;
@@ -382,7 +410,7 @@ static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
return ptr;
}
-static void __finalize_command(struct private_data *priv)
+static void __finalize_command(struct brcmstb_dpfe_priv *priv)
{
unsigned int release_mbox;
@@ -390,12 +418,12 @@ static void __finalize_command(struct private_data *priv)
* It depends on the API version which MBOX register we have to write to
* to signal we are done.
*/
- release_mbox = (priv->dpfe_api->version < 3)
+ release_mbox = (priv->dpfe_api->version < 2)
? REG_TO_HOST_MBOX : REG_TO_DCPU_MBOX;
writel_relaxed(0, priv->regs + release_mbox);
}
-static int __send_command(struct private_data *priv, unsigned int cmd,
+static int __send_command(struct brcmstb_dpfe_priv *priv, unsigned int cmd,
u32 result[])
{
const u32 *msg = priv->dpfe_api->command[cmd];
@@ -421,9 +449,17 @@ static int __send_command(struct private_data *priv, unsigned int cmd,
return -ETIMEDOUT;
}
+ /* Compute checksum over the message */
+ chksum_idx = msg[MSG_ARG_COUNT] + MSG_ARG_COUNT + 1;
+ chksum = get_msg_chksum(msg, chksum_idx);
+
/* Write command and arguments to message area */
- for (i = 0; i < MSG_FIELD_MAX; i++)
- writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
+ for (i = 0; i < MSG_FIELD_MAX; i++) {
+ if (i == chksum_idx)
+ writel_relaxed(chksum, regs + DCPU_MSG_RAM(i));
+ else
+ writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
+ }
/* Tell DCPU there is a command waiting */
writel_relaxed(1, regs + REG_TO_DCPU_MBOX);
@@ -517,7 +553,7 @@ static int __verify_firmware(struct init_data *init,
/* Verify checksum by reading back the firmware from co-processor RAM. */
static int __verify_fw_checksum(struct init_data *init,
- struct private_data *priv,
+ struct brcmstb_dpfe_priv *priv,
const struct dpfe_firmware_header *header,
u32 checksum)
{
@@ -571,26 +607,23 @@ static int __write_firmware(u32 __iomem *mem, const u32 *fw,
return 0;
}
-static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
- struct init_data *init)
+static int brcmstb_dpfe_download_firmware(struct brcmstb_dpfe_priv *priv)
{
const struct dpfe_firmware_header *header;
unsigned int dmem_size, imem_size;
- struct device *dev = &pdev->dev;
+ struct device *dev = priv->dev;
bool is_big_endian = false;
- struct private_data *priv;
const struct firmware *fw;
const u32 *dmem, *imem;
+ struct init_data init;
const void *fw_blob;
int ret;
- priv = platform_get_drvdata(pdev);
-
/*
* Skip downloading the firmware if the DCPU is already running and
* responding to commands.
*/
- if (is_dcpu_enabled(priv->regs)) {
+ if (is_dcpu_enabled(priv)) {
u32 response[MSG_FIELD_MAX];
ret = __send_command(priv, DPFE_CMD_GET_INFO, response);
@@ -606,20 +639,23 @@ static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
if (!priv->dpfe_api->fw_name)
return -ENODEV;
- ret = request_firmware(&fw, priv->dpfe_api->fw_name, dev);
- /* request_firmware() prints its own error messages. */
+ ret = firmware_request_nowarn(&fw, priv->dpfe_api->fw_name, dev);
+ /*
+ * Defer the firmware download if the firmware file couldn't be found.
+ * The root file system may not be available yet.
+ */
if (ret)
- return ret;
+ return (ret == -ENOENT) ? -EPROBE_DEFER : ret;
- ret = __verify_firmware(init, fw);
+ ret = __verify_firmware(&init, fw);
if (ret)
return -EFAULT;
- __disable_dcpu(priv->regs);
+ __disable_dcpu(priv);
- is_big_endian = init->is_big_endian;
- dmem_size = init->dmem_len;
- imem_size = init->imem_len;
+ is_big_endian = init.is_big_endian;
+ dmem_size = init.dmem_len;
+ imem_size = init.imem_len;
/* At the beginning of the firmware blob is a header. */
header = (struct dpfe_firmware_header *)fw->data;
@@ -637,17 +673,17 @@ static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
if (ret)
return ret;
- ret = __verify_fw_checksum(init, priv, header, init->chksum);
+ ret = __verify_fw_checksum(&init, priv, header, init.chksum);
if (ret)
return ret;
- __enable_dcpu(priv->regs);
+ __enable_dcpu(priv);
return 0;
}
static ssize_t generic_show(unsigned int command, u32 response[],
- struct private_data *priv, char *buf)
+ struct brcmstb_dpfe_priv *priv, char *buf)
{
int ret;
@@ -665,7 +701,7 @@ static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
char *buf)
{
u32 response[MSG_FIELD_MAX];
- struct private_data *priv;
+ struct brcmstb_dpfe_priv *priv;
unsigned int info;
ssize_t ret;
@@ -688,7 +724,7 @@ static ssize_t show_refresh(struct device *dev,
{
u32 response[MSG_FIELD_MAX];
void __iomem *info;
- struct private_data *priv;
+ struct brcmstb_dpfe_priv *priv;
u8 refresh, sr_abort, ppre, thermal_offs, tuf;
u32 mr4;
ssize_t ret;
@@ -721,7 +757,7 @@ static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
u32 response[MSG_FIELD_MAX];
- struct private_data *priv;
+ struct brcmstb_dpfe_priv *priv;
void __iomem *info;
unsigned long val;
int ret;
@@ -747,7 +783,7 @@ static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
char *buf)
{
u32 response[MSG_FIELD_MAX];
- struct private_data *priv;
+ struct brcmstb_dpfe_priv *priv;
void __iomem *info;
ssize_t ret;
u32 mr5, mr6, mr7, mr8, err;
@@ -778,7 +814,7 @@ static ssize_t show_dram(struct device *dev, struct device_attribute *devattr,
char *buf)
{
u32 response[MSG_FIELD_MAX];
- struct private_data *priv;
+ struct brcmstb_dpfe_priv *priv;
ssize_t ret;
u32 mr4, mr5, mr6, mr7, mr8, err;
@@ -800,16 +836,15 @@ static ssize_t show_dram(struct device *dev, struct device_attribute *devattr,
static int brcmstb_dpfe_resume(struct platform_device *pdev)
{
- struct init_data init;
+ struct brcmstb_dpfe_priv *priv = platform_get_drvdata(pdev);
- return brcmstb_dpfe_download_firmware(pdev, &init);
+ return brcmstb_dpfe_download_firmware(priv);
}
static int brcmstb_dpfe_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
- struct private_data *priv;
- struct init_data init;
+ struct brcmstb_dpfe_priv *priv;
struct resource *res;
int ret;
@@ -817,6 +852,8 @@ static int brcmstb_dpfe_probe(struct platform_device *pdev)
if (!priv)
return -ENOMEM;
+ priv->dev = dev;
+
mutex_init(&priv->lock);
platform_set_drvdata(pdev, priv);
@@ -851,9 +888,10 @@ static int brcmstb_dpfe_probe(struct platform_device *pdev)
return -ENOENT;
}
- ret = brcmstb_dpfe_download_firmware(pdev, &init);
+ ret = brcmstb_dpfe_download_firmware(priv);
if (ret) {
- dev_err(dev, "Couldn't download firmware -- %d\n", ret);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "Couldn't download firmware -- %d\n", ret);
return ret;
}
@@ -867,7 +905,7 @@ static int brcmstb_dpfe_probe(struct platform_device *pdev)
static int brcmstb_dpfe_remove(struct platform_device *pdev)
{
- struct private_data *priv = dev_get_drvdata(&pdev->dev);
+ struct brcmstb_dpfe_priv *priv = dev_get_drvdata(&pdev->dev);
sysfs_remove_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
@@ -876,10 +914,10 @@ static int brcmstb_dpfe_remove(struct platform_device *pdev)
static const struct of_device_id brcmstb_dpfe_of_match[] = {
/* Use legacy API v2 for a select number of chips */
- { .compatible = "brcm,bcm7268-dpfe-cpu", .data = &dpfe_api_v2 },
- { .compatible = "brcm,bcm7271-dpfe-cpu", .data = &dpfe_api_v2 },
- { .compatible = "brcm,bcm7278-dpfe-cpu", .data = &dpfe_api_v2 },
- { .compatible = "brcm,bcm7211-dpfe-cpu", .data = &dpfe_api_v2 },
+ { .compatible = "brcm,bcm7268-dpfe-cpu", .data = &dpfe_api_old_v2 },
+ { .compatible = "brcm,bcm7271-dpfe-cpu", .data = &dpfe_api_old_v2 },
+ { .compatible = "brcm,bcm7278-dpfe-cpu", .data = &dpfe_api_old_v2 },
+ { .compatible = "brcm,bcm7211-dpfe-cpu", .data = &dpfe_api_new_v2 },
/* API v3 is the default going forward */
{ .compatible = "brcm,dpfe-cpu", .data = &dpfe_api_v3 },
{}
diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index 402c6bc8e621..9d9127bf2a59 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -1613,7 +1613,7 @@ static void emif_shutdown(struct platform_device *pdev)
static int get_emif_reg_values(struct emif_data *emif, u32 freq,
struct emif_regs *regs)
{
- u32 cs1_used, ip_rev, phy_type;
+ u32 ip_rev, phy_type;
u32 cl, type;
const struct lpddr2_timings *timings;
const struct lpddr2_min_tck *min_tck;
@@ -1621,7 +1621,6 @@ static int get_emif_reg_values(struct emif_data *emif, u32 freq,
const struct lpddr2_addressing *addressing;
struct emif_data *emif_for_calc;
struct device *dev;
- const struct emif_custom_configs *custom_configs;
dev = emif->dev;
/*
@@ -1639,12 +1638,10 @@ static int get_emif_reg_values(struct emif_data *emif, u32 freq,
device_info = emif_for_calc->plat_data->device_info;
type = device_info->type;
- cs1_used = device_info->cs1_used;
ip_rev = emif_for_calc->plat_data->ip_rev;
phy_type = emif_for_calc->plat_data->phy_type;
min_tck = emif_for_calc->plat_data->min_tck;
- custom_configs = emif_for_calc->plat_data->custom_configs;
set_ddr_clk_period(freq);
diff --git a/drivers/memory/jedec_ddr.h b/drivers/memory/jedec_ddr.h
index 4a21b5044ff8..e59ccbd982d0 100644
--- a/drivers/memory/jedec_ddr.h
+++ b/drivers/memory/jedec_ddr.h
@@ -29,6 +29,7 @@
#define DDR_TYPE_LPDDR2_S4 3
#define DDR_TYPE_LPDDR2_S2 4
#define DDR_TYPE_LPDDR2_NVM 5
+#define DDR_TYPE_LPDDR3 6
/* DDR IO width */
#define DDR_IO_WIDTH_4 1
@@ -169,4 +170,64 @@ extern const struct lpddr2_timings
lpddr2_jedec_timings[NUM_DDR_TIMING_TABLE_ENTRIES];
extern const struct lpddr2_min_tck lpddr2_jedec_min_tck;
+/*
+ * Structure for timings for LPDDR3 based on LPDDR2 plus additional fields.
+ * All parameters are in pico seconds(ps) excluding max_freq, min_freq which
+ * are in Hz.
+ */
+struct lpddr3_timings {
+ u32 max_freq;
+ u32 min_freq;
+ u32 tRFC;
+ u32 tRRD;
+ u32 tRPab;
+ u32 tRPpb;
+ u32 tRCD;
+ u32 tRC;
+ u32 tRAS;
+ u32 tWTR;
+ u32 tWR;
+ u32 tRTP;
+ u32 tW2W_C2C;
+ u32 tR2R_C2C;
+ u32 tWL;
+ u32 tDQSCK;
+ u32 tRL;
+ u32 tFAW;
+ u32 tXSR;
+ u32 tXP;
+ u32 tCKE;
+ u32 tCKESR;
+ u32 tMRD;
+};
+
+/*
+ * Min value for some parameters in terms of number of tCK cycles(nCK)
+ * Please set to zero parameters that are not valid for a given memory
+ * type
+ */
+struct lpddr3_min_tck {
+ u32 tRFC;
+ u32 tRRD;
+ u32 tRPab;
+ u32 tRPpb;
+ u32 tRCD;
+ u32 tRC;
+ u32 tRAS;
+ u32 tWTR;
+ u32 tWR;
+ u32 tRTP;
+ u32 tW2W_C2C;
+ u32 tR2R_C2C;
+ u32 tWL;
+ u32 tDQSCK;
+ u32 tRL;
+ u32 tFAW;
+ u32 tXSR;
+ u32 tXP;
+ u32 tCKE;
+ u32 tCKESR;
+ u32 tMRD;
+};
+
#endif /* __JEDEC_DDR_H */
diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
index 439d7d886873..a113e811faab 100644
--- a/drivers/memory/mtk-smi.c
+++ b/drivers/memory/mtk-smi.c
@@ -366,6 +366,8 @@ static int __maybe_unused mtk_smi_larb_suspend(struct device *dev)
static const struct dev_pm_ops smi_larb_pm_ops = {
SET_RUNTIME_PM_OPS(mtk_smi_larb_suspend, mtk_smi_larb_resume, NULL)
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
};
static struct platform_driver mtk_smi_larb_driver = {
@@ -507,6 +509,8 @@ static int __maybe_unused mtk_smi_common_suspend(struct device *dev)
static const struct dev_pm_ops smi_common_pm_ops = {
SET_RUNTIME_PM_OPS(mtk_smi_common_suspend, mtk_smi_common_resume, NULL)
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
};
static struct platform_driver mtk_smi_common_driver = {
diff --git a/drivers/memory/of_memory.c b/drivers/memory/of_memory.c
index 46539b27a3fb..71f26eac7350 100644
--- a/drivers/memory/of_memory.c
+++ b/drivers/memory/of_memory.c
@@ -3,6 +3,7 @@
* OpenFirmware helpers for memory drivers
*
* Copyright (C) 2012 Texas Instruments, Inc.
+ * Copyright (C) 2019 Samsung Electronics Co., Ltd.
*/
#include <linux/device.h>
@@ -149,3 +150,151 @@ default_timings:
return lpddr2_jedec_timings;
}
EXPORT_SYMBOL(of_get_ddr_timings);
+
+/**
+ * of_lpddr3_get_min_tck() - extract min timing values for lpddr3
+ * @np: pointer to ddr device tree node
+ * @device: device requesting for min timing values
+ *
+ * Populates the lpddr3_min_tck structure by extracting data
+ * from device tree node. Returns a pointer to the populated
+ * structure. If any error in populating the structure, returns NULL.
+ */
+const struct lpddr3_min_tck *of_lpddr3_get_min_tck(struct device_node *np,
+ struct device *dev)
+{
+ int ret = 0;
+ struct lpddr3_min_tck *min;
+
+ min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);
+ if (!min)
+ goto default_min_tck;
+
+ ret |= of_property_read_u32(np, "tRFC-min-tck", &min->tRFC);
+ ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
+ ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
+ ret |= of_property_read_u32(np, "tRPpb-min-tck", &min->tRPpb);
+ ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
+ ret |= of_property_read_u32(np, "tRC-min-tck", &min->tRC);
+ ret |= of_property_read_u32(np, "tRAS-min-tck", &min->tRAS);
+ ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
+ ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
+ ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
+ ret |= of_property_read_u32(np, "tW2W-C2C-min-tck", &min->tW2W_C2C);
+ ret |= of_property_read_u32(np, "tR2R-C2C-min-tck", &min->tR2R_C2C);
+ ret |= of_property_read_u32(np, "tWL-min-tck", &min->tWL);
+ ret |= of_property_read_u32(np, "tDQSCK-min-tck", &min->tDQSCK);
+ ret |= of_property_read_u32(np, "tRL-min-tck", &min->tRL);
+ ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);
+ ret |= of_property_read_u32(np, "tXSR-min-tck", &min->tXSR);
+ ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
+ ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
+ ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
+ ret |= of_property_read_u32(np, "tMRD-min-tck", &min->tMRD);
+
+ if (ret) {
+ dev_warn(dev, "%s: errors while parsing min-tck values\n",
+ __func__);
+ devm_kfree(dev, min);
+ goto default_min_tck;
+ }
+
+ return min;
+
+default_min_tck:
+ dev_warn(dev, "%s: using default min-tck values\n", __func__);
+ return NULL;
+}
+EXPORT_SYMBOL(of_lpddr3_get_min_tck);
+
+static int of_lpddr3_do_get_timings(struct device_node *np,
+ struct lpddr3_timings *tim)
+{
+ int ret;
+
+ /* The 'reg' param required since DT has changed, used as 'max-freq' */
+ ret = of_property_read_u32(np, "reg", &tim->max_freq);
+ ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
+ ret |= of_property_read_u32(np, "tRFC", &tim->tRFC);
+ ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
+ ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
+ ret |= of_property_read_u32(np, "tRPpb", &tim->tRPpb);
+ ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
+ ret |= of_property_read_u32(np, "tRC", &tim->tRC);
+ ret |= of_property_read_u32(np, "tRAS", &tim->tRAS);
+ ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
+ ret |= of_property_read_u32(np, "tWR", &tim->tWR);
+ ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
+ ret |= of_property_read_u32(np, "tW2W-C2C", &tim->tW2W_C2C);
+ ret |= of_property_read_u32(np, "tR2R-C2C", &tim->tR2R_C2C);
+ ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
+ ret |= of_property_read_u32(np, "tXSR", &tim->tXSR);
+ ret |= of_property_read_u32(np, "tXP", &tim->tXP);
+ ret |= of_property_read_u32(np, "tCKE", &tim->tCKE);
+ ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
+ ret |= of_property_read_u32(np, "tMRD", &tim->tMRD);
+
+ return ret;
+}
+
+/**
+ * of_lpddr3_get_ddr_timings() - extracts the lpddr3 timings and updates no of
+ * frequencies available.
+ * @np_ddr: Pointer to ddr device tree node
+ * @dev: Device requesting for ddr timings
+ * @device_type: Type of ddr
+ * @nr_frequencies: No of frequencies available for ddr
+ * (updated by this function)
+ *
+ * Populates lpddr3_timings structure by extracting data from device
+ * tree node. Returns pointer to populated structure. If any error
+ * while populating, returns NULL.
+ */
+const struct lpddr3_timings
+*of_lpddr3_get_ddr_timings(struct device_node *np_ddr, struct device *dev,
+ u32 device_type, u32 *nr_frequencies)
+{
+ struct lpddr3_timings *timings = NULL;
+ u32 arr_sz = 0, i = 0;
+ struct device_node *np_tim;
+ char *tim_compat = NULL;
+
+ switch (device_type) {
+ case DDR_TYPE_LPDDR3:
+ tim_compat = "jedec,lpddr3-timings";
+ break;
+ default:
+ dev_warn(dev, "%s: un-supported memory type\n", __func__);
+ }
+
+ for_each_child_of_node(np_ddr, np_tim)
+ if (of_device_is_compatible(np_tim, tim_compat))
+ arr_sz++;
+
+ if (arr_sz)
+ timings = devm_kcalloc(dev, arr_sz, sizeof(*timings),
+ GFP_KERNEL);
+
+ if (!timings)
+ goto default_timings;
+
+ for_each_child_of_node(np_ddr, np_tim) {
+ if (of_device_is_compatible(np_tim, tim_compat)) {
+ if (of_lpddr3_do_get_timings(np_tim, &timings[i])) {
+ devm_kfree(dev, timings);
+ goto default_timings;
+ }
+ i++;
+ }
+ }
+
+ *nr_frequencies = arr_sz;
+
+ return timings;
+
+default_timings:
+ dev_warn(dev, "%s: failed to get timings\n", __func__);
+ *nr_frequencies = 0;
+ return NULL;
+}
+EXPORT_SYMBOL(of_lpddr3_get_ddr_timings);
diff --git a/drivers/memory/of_memory.h b/drivers/memory/of_memory.h
index b077cc836b0b..e39ecc4c733d 100644
--- a/drivers/memory/of_memory.h
+++ b/drivers/memory/of_memory.h
@@ -14,6 +14,11 @@ extern const struct lpddr2_min_tck *of_get_min_tck(struct device_node *np,
extern const struct lpddr2_timings
*of_get_ddr_timings(struct device_node *np_ddr, struct device *dev,
u32 device_type, u32 *nr_frequencies);
+extern const struct lpddr3_min_tck
+ *of_lpddr3_get_min_tck(struct device_node *np, struct device *dev);
+extern const struct lpddr3_timings
+ *of_lpddr3_get_ddr_timings(struct device_node *np_ddr,
+ struct device *dev, u32 device_type, u32 *nr_frequencies);
#else
static inline const struct lpddr2_min_tck
*of_get_min_tck(struct device_node *np, struct device *dev)
@@ -27,6 +32,19 @@ static inline const struct lpddr2_timings
{
return NULL;
}
+
+static inline const struct lpddr3_min_tck
+ *of_lpddr3_get_min_tck(struct device_node *np, struct device *dev)
+{
+ return NULL;
+}
+
+static inline const struct lpddr3_timings
+ *of_lpddr3_get_ddr_timings(struct device_node *np_ddr,
+ struct device *dev, u32 device_type, u32 *nr_frequencies)
+{
+ return NULL;
+}
#endif /* CONFIG_OF && CONFIG_DDR */
#endif /* __LINUX_MEMORY_OF_REG_ */
diff --git a/drivers/memory/samsung/Kconfig b/drivers/memory/samsung/Kconfig
index 79ce7ea58903..e9c3ce92350c 100644
--- a/drivers/memory/samsung/Kconfig
+++ b/drivers/memory/samsung/Kconfig
@@ -7,6 +7,19 @@ config SAMSUNG_MC
if SAMSUNG_MC
+config EXYNOS5422_DMC
+ tristate "EXYNOS5422 Dynamic Memory Controller driver"
+ depends on ARCH_EXYNOS || (COMPILE_TEST && HAS_IOMEM)
+ select DDR
+ depends on DEVFREQ_GOV_SIMPLE_ONDEMAND
+ depends on (PM_DEVFREQ && PM_DEVFREQ_EVENT)
+ help
+ This adds driver for Exynos5422 DMC (Dynamic Memory Controller).
+ The driver provides support for Dynamic Voltage and Frequency Scaling in
+ DMC and DRAM. It also supports changing timings of DRAM running with
+ different frequency. The timings are calculated based on DT memory
+ information.
+
config EXYNOS_SROM
bool "Exynos SROM controller driver" if COMPILE_TEST
depends on (ARM && ARCH_EXYNOS) || (COMPILE_TEST && HAS_IOMEM)
diff --git a/drivers/memory/samsung/Makefile b/drivers/memory/samsung/Makefile
index 00587be66211..ea071be21c44 100644
--- a/drivers/memory/samsung/Makefile
+++ b/drivers/memory/samsung/Makefile
@@ -1,2 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_EXYNOS5422_DMC) += exynos5422-dmc.o
obj-$(CONFIG_EXYNOS_SROM) += exynos-srom.o
diff --git a/drivers/memory/samsung/exynos5422-dmc.c b/drivers/memory/samsung/exynos5422-dmc.c
new file mode 100644
index 000000000000..47dbf6d1789f
--- /dev/null
+++ b/drivers/memory/samsung/exynos5422-dmc.c
@@ -0,0 +1,1550 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd.
+ * Author: Lukasz Luba <l.luba@partner.samsung.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/devfreq-event.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pm_opp.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include "../jedec_ddr.h"
+#include "../of_memory.h"
+
+#define EXYNOS5_DREXI_TIMINGAREF (0x0030)
+#define EXYNOS5_DREXI_TIMINGROW0 (0x0034)
+#define EXYNOS5_DREXI_TIMINGDATA0 (0x0038)
+#define EXYNOS5_DREXI_TIMINGPOWER0 (0x003C)
+#define EXYNOS5_DREXI_TIMINGROW1 (0x00E4)
+#define EXYNOS5_DREXI_TIMINGDATA1 (0x00E8)
+#define EXYNOS5_DREXI_TIMINGPOWER1 (0x00EC)
+#define CDREX_PAUSE (0x2091c)
+#define CDREX_LPDDR3PHY_CON3 (0x20a20)
+#define CDREX_LPDDR3PHY_CLKM_SRC (0x20700)
+#define EXYNOS5_TIMING_SET_SWI BIT(28)
+#define USE_MX_MSPLL_TIMINGS (1)
+#define USE_BPLL_TIMINGS (0)
+#define EXYNOS5_AREF_NORMAL (0x2e)
+
+#define DREX_PPCCLKCON (0x0130)
+#define DREX_PEREV2CONFIG (0x013c)
+#define DREX_PMNC_PPC (0xE000)
+#define DREX_CNTENS_PPC (0xE010)
+#define DREX_CNTENC_PPC (0xE020)
+#define DREX_INTENS_PPC (0xE030)
+#define DREX_INTENC_PPC (0xE040)
+#define DREX_FLAG_PPC (0xE050)
+#define DREX_PMCNT2_PPC (0xE130)
+
+/*
+ * A value for register DREX_PMNC_PPC which should be written to reset
+ * the cycle counter CCNT (a reference wall clock). It sets zero to the
+ * CCNT counter.
+ */
+#define CC_RESET BIT(2)
+
+/*
+ * A value for register DREX_PMNC_PPC which does the reset of all performance
+ * counters to zero.
+ */
+#define PPC_COUNTER_RESET BIT(1)
+
+/*
+ * Enables all configured counters (including cycle counter). The value should
+ * be written to the register DREX_PMNC_PPC.
+ */
+#define PPC_ENABLE BIT(0)
+
+/* A value for register DREX_PPCCLKCON which enables performance events clock.
+ * Must be written before first access to the performance counters register
+ * set, otherwise it could crash.
+ */
+#define PEREV_CLK_EN BIT(0)
+
+/*
+ * Values which are used to enable counters, interrupts or configure flags of
+ * the performance counters. They configure counter 2 and cycle counter.
+ */
+#define PERF_CNT2 BIT(2)
+#define PERF_CCNT BIT(31)
+
+/*
+ * Performance event types which are used for setting the preferred event
+ * to track in the counters.
+ * There is a set of different types, the values are from range 0 to 0x6f.
+ * These settings should be written to the configuration register which manages
+ * the type of the event (register DREX_PEREV2CONFIG).
+ */
+#define READ_TRANSFER_CH0 (0x6d)
+#define READ_TRANSFER_CH1 (0x6f)
+
+#define PERF_COUNTER_START_VALUE 0xff000000
+#define PERF_EVENT_UP_DOWN_THRESHOLD 900000000ULL
+
+/**
+ * struct dmc_opp_table - Operating level desciption
+ *
+ * Covers frequency and voltage settings of the DMC operating mode.
+ */
+struct dmc_opp_table {
+ u32 freq_hz;
+ u32 volt_uv;
+};
+
+/**
+ * struct exynos5_dmc - main structure describing DMC device
+ *
+ * The main structure for the Dynamic Memory Controller which covers clocks,
+ * memory regions, HW information, parameters and current operating mode.
+ */
+struct exynos5_dmc {
+ struct device *dev;
+ struct devfreq *df;
+ struct devfreq_simple_ondemand_data gov_data;
+ void __iomem *base_drexi0;
+ void __iomem *base_drexi1;
+ struct regmap *clk_regmap;
+ struct mutex lock;
+ unsigned long curr_rate;
+ unsigned long curr_volt;
+ unsigned long bypass_rate;
+ struct dmc_opp_table *opp;
+ struct dmc_opp_table opp_bypass;
+ int opp_count;
+ u32 timings_arr_size;
+ u32 *timing_row;
+ u32 *timing_data;
+ u32 *timing_power;
+ const struct lpddr3_timings *timings;
+ const struct lpddr3_min_tck *min_tck;
+ u32 bypass_timing_row;
+ u32 bypass_timing_data;
+ u32 bypass_timing_power;
+ struct regulator *vdd_mif;
+ struct clk *fout_spll;
+ struct clk *fout_bpll;
+ struct clk *mout_spll;
+ struct clk *mout_bpll;
+ struct clk *mout_mclk_cdrex;
+ struct clk *mout_mx_mspll_ccore;
+ struct clk *mx_mspll_ccore_phy;
+ struct clk *mout_mx_mspll_ccore_phy;
+ struct devfreq_event_dev **counter;
+ int num_counters;
+ u64 last_overflow_ts[2];
+ unsigned long load;
+ unsigned long total;
+ bool in_irq_mode;
+};
+
+#define TIMING_FIELD(t_name, t_bit_beg, t_bit_end) \
+ { .name = t_name, .bit_beg = t_bit_beg, .bit_end = t_bit_end }
+
+#define TIMING_VAL2REG(timing, t_val) \
+({ \
+ u32 __val; \
+ __val = (t_val) << (timing)->bit_beg; \
+ __val; \
+})
+
+struct timing_reg {
+ char *name;
+ int bit_beg;
+ int bit_end;
+ unsigned int val;
+};
+
+static const struct timing_reg timing_row[] = {
+ TIMING_FIELD("tRFC", 24, 31),
+ TIMING_FIELD("tRRD", 20, 23),
+ TIMING_FIELD("tRP", 16, 19),
+ TIMING_FIELD("tRCD", 12, 15),
+ TIMING_FIELD("tRC", 6, 11),
+ TIMING_FIELD("tRAS", 0, 5),
+};
+
+static const struct timing_reg timing_data[] = {
+ TIMING_FIELD("tWTR", 28, 31),
+ TIMING_FIELD("tWR", 24, 27),
+ TIMING_FIELD("tRTP", 20, 23),
+ TIMING_FIELD("tW2W-C2C", 14, 14),
+ TIMING_FIELD("tR2R-C2C", 12, 12),
+ TIMING_FIELD("WL", 8, 11),
+ TIMING_FIELD("tDQSCK", 4, 7),
+ TIMING_FIELD("RL", 0, 3),
+};
+
+static const struct timing_reg timing_power[] = {
+ TIMING_FIELD("tFAW", 26, 31),
+ TIMING_FIELD("tXSR", 16, 25),
+ TIMING_FIELD("tXP", 8, 15),
+ TIMING_FIELD("tCKE", 4, 7),
+ TIMING_FIELD("tMRD", 0, 3),
+};
+
+#define TIMING_COUNT (ARRAY_SIZE(timing_row) + ARRAY_SIZE(timing_data) + \
+ ARRAY_SIZE(timing_power))
+
+static int exynos5_counters_set_event(struct exynos5_dmc *dmc)
+{
+ int i, ret;
+
+ for (i = 0; i < dmc->num_counters; i++) {
+ if (!dmc->counter[i])
+ continue;
+ ret = devfreq_event_set_event(dmc->counter[i]);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static int exynos5_counters_enable_edev(struct exynos5_dmc *dmc)
+{
+ int i, ret;
+
+ for (i = 0; i < dmc->num_counters; i++) {
+ if (!dmc->counter[i])
+ continue;
+ ret = devfreq_event_enable_edev(dmc->counter[i]);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static int exynos5_counters_disable_edev(struct exynos5_dmc *dmc)
+{
+ int i, ret;
+
+ for (i = 0; i < dmc->num_counters; i++) {
+ if (!dmc->counter[i])
+ continue;
+ ret = devfreq_event_disable_edev(dmc->counter[i]);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/**
+ * find_target_freq_id() - Finds requested frequency in local DMC configuration
+ * @dmc: device for which the information is checked
+ * @target_rate: requested frequency in KHz
+ *
+ * Seeks in the local DMC driver structure for the requested frequency value
+ * and returns index or error value.
+ */
+static int find_target_freq_idx(struct exynos5_dmc *dmc,
+ unsigned long target_rate)
+{
+ int i;
+
+ for (i = dmc->opp_count - 1; i >= 0; i--)
+ if (dmc->opp[i].freq_hz <= target_rate)
+ return i;
+
+ return -EINVAL;
+}
+
+/**
+ * exynos5_switch_timing_regs() - Changes bank register set for DRAM timings
+ * @dmc: device for which the new settings is going to be applied
+ * @set: boolean variable passing set value
+ *
+ * Changes the register set, which holds timing parameters.
+ * There is two register sets: 0 and 1. The register set 0
+ * is used in normal operation when the clock is provided from main PLL.
+ * The bank register set 1 is used when the main PLL frequency is going to be
+ * changed and the clock is taken from alternative, stable source.
+ * This function switches between these banks according to the
+ * currently used clock source.
+ */
+static void exynos5_switch_timing_regs(struct exynos5_dmc *dmc, bool set)
+{
+ unsigned int reg;
+ int ret;
+
+ ret = regmap_read(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, &reg);
+
+ if (set)
+ reg |= EXYNOS5_TIMING_SET_SWI;
+ else
+ reg &= ~EXYNOS5_TIMING_SET_SWI;
+
+ regmap_write(dmc->clk_regmap, CDREX_LPDDR3PHY_CON3, reg);
+}
+
+/**
+ * exynos5_init_freq_table() - Initialized PM OPP framework
+ * @dmc: DMC device for which the frequencies are used for OPP init
+ * @profile: devfreq device's profile
+ *
+ * Populate the devfreq device's OPP table based on current frequency, voltage.
+ */
+static int exynos5_init_freq_table(struct exynos5_dmc *dmc,
+ struct devfreq_dev_profile *profile)
+{
+ int i, ret;
+ int idx;
+ unsigned long freq;
+
+ ret = dev_pm_opp_of_add_table(dmc->dev);
+ if (ret < 0) {
+ dev_err(dmc->dev, "Failed to get OPP table\n");
+ return ret;
+ }
+
+ dmc->opp_count = dev_pm_opp_get_opp_count(dmc->dev);
+
+ dmc->opp = devm_kmalloc_array(dmc->dev, dmc->opp_count,
+ sizeof(struct dmc_opp_table), GFP_KERNEL);
+ if (!dmc->opp)
+ goto err_opp;
+
+ idx = dmc->opp_count - 1;
+ for (i = 0, freq = ULONG_MAX; i < dmc->opp_count; i++, freq--) {
+ struct dev_pm_opp *opp;
+
+ opp = dev_pm_opp_find_freq_floor(dmc->dev, &freq);
+ if (IS_ERR(opp))
+ goto err_opp;
+
+ dmc->opp[idx - i].freq_hz = freq;
+ dmc->opp[idx - i].volt_uv = dev_pm_opp_get_voltage(opp);
+
+ dev_pm_opp_put(opp);
+ }
+
+ return 0;
+
+err_opp:
+ dev_pm_opp_of_remove_table(dmc->dev);
+
+ return -EINVAL;
+}
+
+/**
+ * exynos5_set_bypass_dram_timings() - Low-level changes of the DRAM timings
+ * @dmc: device for which the new settings is going to be applied
+ * @param: DRAM parameters which passes timing data
+ *
+ * Low-level function for changing timings for DRAM memory clocking from
+ * 'bypass' clock source (fixed frequency @400MHz).
+ * It uses timing bank registers set 1.
+ */
+static void exynos5_set_bypass_dram_timings(struct exynos5_dmc *dmc)
+{
+ writel(EXYNOS5_AREF_NORMAL,
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+ writel(dmc->bypass_timing_row,
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW1);
+ writel(dmc->bypass_timing_row,
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW1);
+ writel(dmc->bypass_timing_data,
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA1);
+ writel(dmc->bypass_timing_data,
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA1);
+ writel(dmc->bypass_timing_power,
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER1);
+ writel(dmc->bypass_timing_power,
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER1);
+}
+
+/**
+ * exynos5_dram_change_timings() - Low-level changes of the DRAM final timings
+ * @dmc: device for which the new settings is going to be applied
+ * @target_rate: target frequency of the DMC
+ *
+ * Low-level function for changing timings for DRAM memory operating from main
+ * clock source (BPLL), which can have different frequencies. Thus, each
+ * frequency must have corresponding timings register values in order to keep
+ * the needed delays.
+ * It uses timing bank registers set 0.
+ */
+static int exynos5_dram_change_timings(struct exynos5_dmc *dmc,
+ unsigned long target_rate)
+{
+ int idx;
+
+ for (idx = dmc->opp_count - 1; idx >= 0; idx--)
+ if (dmc->opp[idx].freq_hz <= target_rate)
+ break;
+
+ if (idx < 0)
+ return -EINVAL;
+
+ writel(EXYNOS5_AREF_NORMAL,
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGAREF);
+
+ writel(dmc->timing_row[idx],
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGROW0);
+ writel(dmc->timing_row[idx],
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGROW0);
+ writel(dmc->timing_data[idx],
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGDATA0);
+ writel(dmc->timing_data[idx],
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGDATA0);
+ writel(dmc->timing_power[idx],
+ dmc->base_drexi0 + EXYNOS5_DREXI_TIMINGPOWER0);
+ writel(dmc->timing_power[idx],
+ dmc->base_drexi1 + EXYNOS5_DREXI_TIMINGPOWER0);
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_align_target_voltage() - Sets the final voltage for the DMC
+ * @dmc: device for which it is going to be set
+ * @target_volt: new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for 'normal' mode.
+ * It checks the need of higher voltage and changes the value. The target
+ * voltage might be lower that currently set and still the system will be
+ * stable.
+ */
+static int exynos5_dmc_align_target_voltage(struct exynos5_dmc *dmc,
+ unsigned long target_volt)
+{
+ int ret = 0;
+
+ if (dmc->curr_volt <= target_volt)
+ return 0;
+
+ ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
+ target_volt);
+ if (!ret)
+ dmc->curr_volt = target_volt;
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_voltage() - Sets the voltage for the DMC
+ * @dmc: device for which it is going to be set
+ * @target_volt: new voltage which is chosen to be final
+ *
+ * Function tries to align voltage to the safe level for the 'bypass' mode.
+ * It checks the need of higher voltage and changes the value.
+ * The target voltage must not be less than currently needed, because
+ * for current frequency the device might become unstable.
+ */
+static int exynos5_dmc_align_bypass_voltage(struct exynos5_dmc *dmc,
+ unsigned long target_volt)
+{
+ int ret = 0;
+ unsigned long bypass_volt = dmc->opp_bypass.volt_uv;
+
+ target_volt = max(bypass_volt, target_volt);
+
+ if (dmc->curr_volt >= target_volt)
+ return 0;
+
+ ret = regulator_set_voltage(dmc->vdd_mif, target_volt,
+ target_volt);
+ if (!ret)
+ dmc->curr_volt = target_volt;
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_align_bypass_dram_timings() - Chooses and sets DRAM timings
+ * @dmc: device for which it is going to be set
+ * @target_rate: new frequency which is chosen to be final
+ *
+ * Function changes the DRAM timings for the temporary 'bypass' mode.
+ */
+static int exynos5_dmc_align_bypass_dram_timings(struct exynos5_dmc *dmc,
+ unsigned long target_rate)
+{
+ int idx = find_target_freq_idx(dmc, target_rate);
+
+ if (idx < 0)
+ return -EINVAL;
+
+ exynos5_set_bypass_dram_timings(dmc);
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_switch_to_bypass_configuration() - Switching to temporary clock
+ * @dmc: DMC device for which the switching is going to happen
+ * @target_rate: new frequency which is going to be set as a final
+ * @target_volt: new voltage which is going to be set as a final
+ *
+ * Function configures DMC and clocks for operating in temporary 'bypass' mode.
+ * This mode is used only temporary but if required, changes voltage and timings
+ * for DRAM chips. It switches the main clock to stable clock source for the
+ * period of the main PLL reconfiguration.
+ */
+static int
+exynos5_dmc_switch_to_bypass_configuration(struct exynos5_dmc *dmc,
+ unsigned long target_rate,
+ unsigned long target_volt)
+{
+ int ret;
+
+ /*
+ * Having higher voltage for a particular frequency does not harm
+ * the chip. Use it for the temporary frequency change when one
+ * voltage manipulation might be avoided.
+ */
+ ret = exynos5_dmc_align_bypass_voltage(dmc, target_volt);
+ if (ret)
+ return ret;
+
+ /*
+ * Longer delays for DRAM does not cause crash, the opposite does.
+ */
+ ret = exynos5_dmc_align_bypass_dram_timings(dmc, target_rate);
+ if (ret)
+ return ret;
+
+ /*
+ * Delays are long enough, so use them for the new coming clock.
+ */
+ exynos5_switch_timing_regs(dmc, USE_MX_MSPLL_TIMINGS);
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_change_freq_and_volt() - Changes voltage and frequency of the DMC
+ * using safe procedure
+ * @dmc: device for which the frequency is going to be changed
+ * @target_rate: requested new frequency
+ * @target_volt: requested voltage which corresponds to the new frequency
+ *
+ * The DMC frequency change procedure requires a few steps.
+ * The main requirement is to change the clock source in the clk mux
+ * for the time of main clock PLL locking. The assumption is that the
+ * alternative clock source set as parent is stable.
+ * The second parent's clock frequency is fixed to 400MHz, it is named 'bypass'
+ * clock. This requires alignment in DRAM timing parameters for the new
+ * T-period. There is two bank sets for keeping DRAM
+ * timings: set 0 and set 1. The set 0 is used when main clock source is
+ * chosen. The 2nd set of regs is used for 'bypass' clock. Switching between
+ * the two bank sets is part of the process.
+ * The voltage must also be aligned to the minimum required level. There is
+ * this intermediate step with switching to 'bypass' parent clock source.
+ * if the old voltage is lower, it requires an increase of the voltage level.
+ * The complexity of the voltage manipulation is hidden in low level function.
+ * In this function there is last alignment of the voltage level at the end.
+ */
+static int
+exynos5_dmc_change_freq_and_volt(struct exynos5_dmc *dmc,
+ unsigned long target_rate,
+ unsigned long target_volt)
+{
+ int ret;
+
+ ret = exynos5_dmc_switch_to_bypass_configuration(dmc, target_rate,
+ target_volt);
+ if (ret)
+ return ret;
+
+ /*
+ * Voltage is set at least to a level needed for this frequency,
+ * so switching clock source is safe now.
+ */
+ clk_prepare_enable(dmc->fout_spll);
+ clk_prepare_enable(dmc->mout_spll);
+ clk_prepare_enable(dmc->mout_mx_mspll_ccore);
+
+ ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_mx_mspll_ccore);
+ if (ret)
+ goto disable_clocks;
+
+ /*
+ * We are safe to increase the timings for current bypass frequency.
+ * Thanks to this the settings will be ready for the upcoming clock
+ * source change.
+ */
+ exynos5_dram_change_timings(dmc, target_rate);
+
+ clk_set_rate(dmc->fout_bpll, target_rate);
+
+ exynos5_switch_timing_regs(dmc, USE_BPLL_TIMINGS);
+
+ ret = clk_set_parent(dmc->mout_mclk_cdrex, dmc->mout_bpll);
+ if (ret)
+ goto disable_clocks;
+
+ /*
+ * Make sure if the voltage is not from 'bypass' settings and align to
+ * the right level for power efficiency.
+ */
+ ret = exynos5_dmc_align_target_voltage(dmc, target_volt);
+
+disable_clocks:
+ clk_disable_unprepare(dmc->mout_mx_mspll_ccore);
+ clk_disable_unprepare(dmc->mout_spll);
+ clk_disable_unprepare(dmc->fout_spll);
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_get_volt_freq() - Gets the frequency and voltage from the OPP
+ * table.
+ * @dmc: device for which the frequency is going to be changed
+ * @freq: requested frequency in KHz
+ * @target_rate: returned frequency which is the same or lower than
+ * requested
+ * @target_volt: returned voltage which corresponds to the returned
+ * frequency
+ *
+ * Function gets requested frequency and checks OPP framework for needed
+ * frequency and voltage. It populates the values 'target_rate' and
+ * 'target_volt' or returns error value when OPP framework fails.
+ */
+static int exynos5_dmc_get_volt_freq(struct exynos5_dmc *dmc,
+ unsigned long *freq,
+ unsigned long *target_rate,
+ unsigned long *target_volt, u32 flags)
+{
+ struct dev_pm_opp *opp;
+
+ opp = devfreq_recommended_opp(dmc->dev, freq, flags);
+ if (IS_ERR(opp))
+ return PTR_ERR(opp);
+
+ *target_rate = dev_pm_opp_get_freq(opp);
+ *target_volt = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_target() - Function responsible for changing frequency of DMC
+ * @dev: device for which the frequency is going to be changed
+ * @freq: requested frequency in KHz
+ * @flags: flags provided for this frequency change request
+ *
+ * An entry function provided to the devfreq framework which provides frequency
+ * change of the DMC. The function gets the possible rate from OPP table based
+ * on requested frequency. It calls the next function responsible for the
+ * frequency and voltage change. In case of failure, does not set 'curr_rate'
+ * and returns error value to the framework.
+ */
+static int exynos5_dmc_target(struct device *dev, unsigned long *freq,
+ u32 flags)
+{
+ struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+ unsigned long target_rate = 0;
+ unsigned long target_volt = 0;
+ int ret;
+
+ ret = exynos5_dmc_get_volt_freq(dmc, freq, &target_rate, &target_volt,
+ flags);
+
+ if (ret)
+ return ret;
+
+ if (target_rate == dmc->curr_rate)
+ return 0;
+
+ mutex_lock(&dmc->lock);
+
+ ret = exynos5_dmc_change_freq_and_volt(dmc, target_rate, target_volt);
+
+ if (ret) {
+ mutex_unlock(&dmc->lock);
+ return ret;
+ }
+
+ dmc->curr_rate = target_rate;
+
+ mutex_unlock(&dmc->lock);
+ return 0;
+}
+
+/**
+ * exynos5_counters_get() - Gets the performance counters values.
+ * @dmc: device for which the counters are going to be checked
+ * @load_count: variable which is populated with counter value
+ * @total_count: variable which is used as 'wall clock' reference
+ *
+ * Function which provides performance counters values. It sums up counters for
+ * two DMC channels. The 'total_count' is used as a reference and max value.
+ * The ratio 'load_count/total_count' shows the busy percentage [0%, 100%].
+ */
+static int exynos5_counters_get(struct exynos5_dmc *dmc,
+ unsigned long *load_count,
+ unsigned long *total_count)
+{
+ unsigned long total = 0;
+ struct devfreq_event_data event;
+ int ret, i;
+
+ *load_count = 0;
+
+ /* Take into account only read+write counters, but stop all */
+ for (i = 0; i < dmc->num_counters; i++) {
+ if (!dmc->counter[i])
+ continue;
+
+ ret = devfreq_event_get_event(dmc->counter[i], &event);
+ if (ret < 0)
+ return ret;
+
+ *load_count += event.load_count;
+
+ if (total < event.total_count)
+ total = event.total_count;
+ }
+
+ *total_count = total;
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_start_perf_events() - Setup and start performance event counters
+ * @dmc: device for which the counters are going to be checked
+ * @beg_value: initial value for the counter
+ *
+ * Function which enables needed counters, interrupts and sets initial values
+ * then starts the counters.
+ */
+static void exynos5_dmc_start_perf_events(struct exynos5_dmc *dmc,
+ u32 beg_value)
+{
+ /* Enable interrupts for counter 2 */
+ writel(PERF_CNT2, dmc->base_drexi0 + DREX_INTENS_PPC);
+ writel(PERF_CNT2, dmc->base_drexi1 + DREX_INTENS_PPC);
+
+ /* Enable counter 2 and CCNT */
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi0 + DREX_CNTENS_PPC);
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi1 + DREX_CNTENS_PPC);
+
+ /* Clear overflow flag for all counters */
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi0 + DREX_FLAG_PPC);
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi1 + DREX_FLAG_PPC);
+
+ /* Reset all counters */
+ writel(CC_RESET | PPC_COUNTER_RESET, dmc->base_drexi0 + DREX_PMNC_PPC);
+ writel(CC_RESET | PPC_COUNTER_RESET, dmc->base_drexi1 + DREX_PMNC_PPC);
+
+ /*
+ * Set start value for the counters, the number of samples that
+ * will be gathered is calculated as: 0xffffffff - beg_value
+ */
+ writel(beg_value, dmc->base_drexi0 + DREX_PMCNT2_PPC);
+ writel(beg_value, dmc->base_drexi1 + DREX_PMCNT2_PPC);
+
+ /* Start all counters */
+ writel(PPC_ENABLE, dmc->base_drexi0 + DREX_PMNC_PPC);
+ writel(PPC_ENABLE, dmc->base_drexi1 + DREX_PMNC_PPC);
+}
+
+/**
+ * exynos5_dmc_perf_events_calc() - Calculate utilization
+ * @dmc: device for which the counters are going to be checked
+ * @diff_ts: time between last interrupt and current one
+ *
+ * Function which calculates needed utilization for the devfreq governor.
+ * It prepares values for 'busy_time' and 'total_time' based on elapsed time
+ * between interrupts, which approximates utilization.
+ */
+static void exynos5_dmc_perf_events_calc(struct exynos5_dmc *dmc, u64 diff_ts)
+{
+ /*
+ * This is a simple algorithm for managing traffic on DMC.
+ * When there is almost no load the counters overflow every 4s,
+ * no mater the DMC frequency.
+ * The high load might be approximated using linear function.
+ * Knowing that, simple calculation can provide 'busy_time' and
+ * 'total_time' to the devfreq governor which picks up target
+ * frequency.
+ * We want a fast ramp up and slow decay in frequency change function.
+ */
+ if (diff_ts < PERF_EVENT_UP_DOWN_THRESHOLD) {
+ /*
+ * Set higher utilization for the simple_ondemand governor.
+ * The governor should increase the frequency of the DMC.
+ */
+ dmc->load = 70;
+ dmc->total = 100;
+ } else {
+ /*
+ * Set low utilization for the simple_ondemand governor.
+ * The governor should decrease the frequency of the DMC.
+ */
+ dmc->load = 35;
+ dmc->total = 100;
+ }
+
+ dev_dbg(dmc->dev, "diff_ts=%llu\n", diff_ts);
+}
+
+/**
+ * exynos5_dmc_perf_events_check() - Checks the status of the counters
+ * @dmc: device for which the counters are going to be checked
+ *
+ * Function which is called from threaded IRQ to check the counters state
+ * and to call approximation for the needed utilization.
+ */
+static void exynos5_dmc_perf_events_check(struct exynos5_dmc *dmc)
+{
+ u32 val;
+ u64 diff_ts, ts;
+
+ ts = ktime_get_ns();
+
+ /* Stop all counters */
+ writel(0, dmc->base_drexi0 + DREX_PMNC_PPC);
+ writel(0, dmc->base_drexi1 + DREX_PMNC_PPC);
+
+ /* Check the source in interrupt flag registers (which channel) */
+ val = readl(dmc->base_drexi0 + DREX_FLAG_PPC);
+ if (val) {
+ diff_ts = ts - dmc->last_overflow_ts[0];
+ dmc->last_overflow_ts[0] = ts;
+ dev_dbg(dmc->dev, "drex0 0xE050 val= 0x%08x\n", val);
+ } else {
+ val = readl(dmc->base_drexi1 + DREX_FLAG_PPC);
+ diff_ts = ts - dmc->last_overflow_ts[1];
+ dmc->last_overflow_ts[1] = ts;
+ dev_dbg(dmc->dev, "drex1 0xE050 val= 0x%08x\n", val);
+ }
+
+ exynos5_dmc_perf_events_calc(dmc, diff_ts);
+
+ exynos5_dmc_start_perf_events(dmc, PERF_COUNTER_START_VALUE);
+}
+
+/**
+ * exynos5_dmc_enable_perf_events() - Enable performance events
+ * @dmc: device for which the counters are going to be checked
+ *
+ * Function which is setup needed environment and enables counters.
+ */
+static void exynos5_dmc_enable_perf_events(struct exynos5_dmc *dmc)
+{
+ u64 ts;
+
+ /* Enable Performance Event Clock */
+ writel(PEREV_CLK_EN, dmc->base_drexi0 + DREX_PPCCLKCON);
+ writel(PEREV_CLK_EN, dmc->base_drexi1 + DREX_PPCCLKCON);
+
+ /* Select read transfers as performance event2 */
+ writel(READ_TRANSFER_CH0, dmc->base_drexi0 + DREX_PEREV2CONFIG);
+ writel(READ_TRANSFER_CH1, dmc->base_drexi1 + DREX_PEREV2CONFIG);
+
+ ts = ktime_get_ns();
+ dmc->last_overflow_ts[0] = ts;
+ dmc->last_overflow_ts[1] = ts;
+
+ /* Devfreq shouldn't be faster than initialization, play safe though. */
+ dmc->load = 99;
+ dmc->total = 100;
+}
+
+/**
+ * exynos5_dmc_disable_perf_events() - Disable performance events
+ * @dmc: device for which the counters are going to be checked
+ *
+ * Function which stops, disables performance event counters and interrupts.
+ */
+static void exynos5_dmc_disable_perf_events(struct exynos5_dmc *dmc)
+{
+ /* Stop all counters */
+ writel(0, dmc->base_drexi0 + DREX_PMNC_PPC);
+ writel(0, dmc->base_drexi1 + DREX_PMNC_PPC);
+
+ /* Disable interrupts for counter 2 */
+ writel(PERF_CNT2, dmc->base_drexi0 + DREX_INTENC_PPC);
+ writel(PERF_CNT2, dmc->base_drexi1 + DREX_INTENC_PPC);
+
+ /* Disable counter 2 and CCNT */
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi0 + DREX_CNTENC_PPC);
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi1 + DREX_CNTENC_PPC);
+
+ /* Clear overflow flag for all counters */
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi0 + DREX_FLAG_PPC);
+ writel(PERF_CNT2 | PERF_CCNT, dmc->base_drexi1 + DREX_FLAG_PPC);
+}
+
+/**
+ * exynos5_dmc_get_status() - Read current DMC performance statistics.
+ * @dev: device for which the statistics are requested
+ * @stat: structure which has statistic fields
+ *
+ * Function reads the DMC performance counters and calculates 'busy_time'
+ * and 'total_time'. To protect from overflow, the values are shifted right
+ * by 10. After read out the counters are setup to count again.
+ */
+static int exynos5_dmc_get_status(struct device *dev,
+ struct devfreq_dev_status *stat)
+{
+ struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+ unsigned long load, total;
+ int ret;
+
+ if (dmc->in_irq_mode) {
+ stat->current_frequency = dmc->curr_rate;
+ stat->busy_time = dmc->load;
+ stat->total_time = dmc->total;
+ } else {
+ ret = exynos5_counters_get(dmc, &load, &total);
+ if (ret < 0)
+ return -EINVAL;
+
+ /* To protect from overflow, divide by 1024 */
+ stat->busy_time = load >> 10;
+ stat->total_time = total >> 10;
+
+ ret = exynos5_counters_set_event(dmc);
+ if (ret < 0) {
+ dev_err(dev, "could not set event counter\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_get_cur_freq() - Function returns current DMC frequency
+ * @dev: device for which the framework checks operating frequency
+ * @freq: returned frequency value
+ *
+ * It returns the currently used frequency of the DMC. The real operating
+ * frequency might be lower when the clock source value could not be divided
+ * to the requested value.
+ */
+static int exynos5_dmc_get_cur_freq(struct device *dev, unsigned long *freq)
+{
+ struct exynos5_dmc *dmc = dev_get_drvdata(dev);
+
+ mutex_lock(&dmc->lock);
+ *freq = dmc->curr_rate;
+ mutex_unlock(&dmc->lock);
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_df_profile - Devfreq governor's profile structure
+ *
+ * It provides to the devfreq framework needed functions and polling period.
+ */
+static struct devfreq_dev_profile exynos5_dmc_df_profile = {
+ .target = exynos5_dmc_target,
+ .get_dev_status = exynos5_dmc_get_status,
+ .get_cur_freq = exynos5_dmc_get_cur_freq,
+};
+
+/**
+ * exynos5_dmc_align_initial_frequency() - Align initial frequency value
+ * @dmc: device for which the frequency is going to be set
+ * @bootloader_init_freq: initial frequency set by the bootloader in KHz
+ *
+ * The initial bootloader frequency, which is present during boot, might be
+ * different that supported frequency values in the driver. It is possible
+ * due to different PLL settings or used PLL as a source.
+ * This function provides the 'initial_freq' for the devfreq framework
+ * statistics engine which supports only registered values. Thus, some alignment
+ * must be made.
+ */
+static unsigned long
+exynos5_dmc_align_init_freq(struct exynos5_dmc *dmc,
+ unsigned long bootloader_init_freq)
+{
+ unsigned long aligned_freq;
+ int idx;
+
+ idx = find_target_freq_idx(dmc, bootloader_init_freq);
+ if (idx >= 0)
+ aligned_freq = dmc->opp[idx].freq_hz;
+ else
+ aligned_freq = dmc->opp[dmc->opp_count - 1].freq_hz;
+
+ return aligned_freq;
+}
+
+/**
+ * create_timings_aligned() - Create register values and align with standard
+ * @dmc: device for which the frequency is going to be set
+ * @idx: speed bin in the OPP table
+ * @clk_period_ps: the period of the clock, known as tCK
+ *
+ * The function calculates timings and creates a register value ready for
+ * a frequency transition. The register contains a few timings. They are
+ * shifted by a known offset. The timing value is calculated based on memory
+ * specyfication: minimal time required and minimal cycles required.
+ */
+static int create_timings_aligned(struct exynos5_dmc *dmc, u32 *reg_timing_row,
+ u32 *reg_timing_data, u32 *reg_timing_power,
+ u32 clk_period_ps)
+{
+ u32 val;
+ const struct timing_reg *reg;
+
+ if (clk_period_ps == 0)
+ return -EINVAL;
+
+ *reg_timing_row = 0;
+ *reg_timing_data = 0;
+ *reg_timing_power = 0;
+
+ val = dmc->timings->tRFC / clk_period_ps;
+ val += dmc->timings->tRFC % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRFC);
+ reg = &timing_row[0];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRRD / clk_period_ps;
+ val += dmc->timings->tRRD % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRRD);
+ reg = &timing_row[1];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRPab / clk_period_ps;
+ val += dmc->timings->tRPab % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRPab);
+ reg = &timing_row[2];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRCD / clk_period_ps;
+ val += dmc->timings->tRCD % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRCD);
+ reg = &timing_row[3];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRC / clk_period_ps;
+ val += dmc->timings->tRC % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRC);
+ reg = &timing_row[4];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRAS / clk_period_ps;
+ val += dmc->timings->tRAS % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRAS);
+ reg = &timing_row[5];
+ *reg_timing_row |= TIMING_VAL2REG(reg, val);
+
+ /* data related timings */
+ val = dmc->timings->tWTR / clk_period_ps;
+ val += dmc->timings->tWTR % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tWTR);
+ reg = &timing_data[0];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tWR / clk_period_ps;
+ val += dmc->timings->tWR % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tWR);
+ reg = &timing_data[1];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRTP / clk_period_ps;
+ val += dmc->timings->tRTP % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRTP);
+ reg = &timing_data[2];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tW2W_C2C / clk_period_ps;
+ val += dmc->timings->tW2W_C2C % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tW2W_C2C);
+ reg = &timing_data[3];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tR2R_C2C / clk_period_ps;
+ val += dmc->timings->tR2R_C2C % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tR2R_C2C);
+ reg = &timing_data[4];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tWL / clk_period_ps;
+ val += dmc->timings->tWL % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tWL);
+ reg = &timing_data[5];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tDQSCK / clk_period_ps;
+ val += dmc->timings->tDQSCK % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tDQSCK);
+ reg = &timing_data[6];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tRL / clk_period_ps;
+ val += dmc->timings->tRL % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tRL);
+ reg = &timing_data[7];
+ *reg_timing_data |= TIMING_VAL2REG(reg, val);
+
+ /* power related timings */
+ val = dmc->timings->tFAW / clk_period_ps;
+ val += dmc->timings->tFAW % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tXP);
+ reg = &timing_power[0];
+ *reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tXSR / clk_period_ps;
+ val += dmc->timings->tXSR % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tXSR);
+ reg = &timing_power[1];
+ *reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tXP / clk_period_ps;
+ val += dmc->timings->tXP % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tXP);
+ reg = &timing_power[2];
+ *reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tCKE / clk_period_ps;
+ val += dmc->timings->tCKE % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tCKE);
+ reg = &timing_power[3];
+ *reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+ val = dmc->timings->tMRD / clk_period_ps;
+ val += dmc->timings->tMRD % clk_period_ps ? 1 : 0;
+ val = max(val, dmc->min_tck->tMRD);
+ reg = &timing_power[4];
+ *reg_timing_power |= TIMING_VAL2REG(reg, val);
+
+ return 0;
+}
+
+/**
+ * of_get_dram_timings() - helper function for parsing DT settings for DRAM
+ * @dmc: device for which the frequency is going to be set
+ *
+ * The function parses DT entries with DRAM information.
+ */
+static int of_get_dram_timings(struct exynos5_dmc *dmc)
+{
+ int ret = 0;
+ int idx;
+ struct device_node *np_ddr;
+ u32 freq_mhz, clk_period_ps;
+
+ np_ddr = of_parse_phandle(dmc->dev->of_node, "device-handle", 0);
+ if (!np_ddr) {
+ dev_warn(dmc->dev, "could not find 'device-handle' in DT\n");
+ return -EINVAL;
+ }
+
+ dmc->timing_row = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+ sizeof(u32), GFP_KERNEL);
+ if (!dmc->timing_row)
+ return -ENOMEM;
+
+ dmc->timing_data = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+ sizeof(u32), GFP_KERNEL);
+ if (!dmc->timing_data)
+ return -ENOMEM;
+
+ dmc->timing_power = devm_kmalloc_array(dmc->dev, TIMING_COUNT,
+ sizeof(u32), GFP_KERNEL);
+ if (!dmc->timing_power)
+ return -ENOMEM;
+
+ dmc->timings = of_lpddr3_get_ddr_timings(np_ddr, dmc->dev,
+ DDR_TYPE_LPDDR3,
+ &dmc->timings_arr_size);
+ if (!dmc->timings) {
+ of_node_put(np_ddr);
+ dev_warn(dmc->dev, "could not get timings from DT\n");
+ return -EINVAL;
+ }
+
+ dmc->min_tck = of_lpddr3_get_min_tck(np_ddr, dmc->dev);
+ if (!dmc->min_tck) {
+ of_node_put(np_ddr);
+ dev_warn(dmc->dev, "could not get tck from DT\n");
+ return -EINVAL;
+ }
+
+ /* Sorted array of OPPs with frequency ascending */
+ for (idx = 0; idx < dmc->opp_count; idx++) {
+ freq_mhz = dmc->opp[idx].freq_hz / 1000000;
+ clk_period_ps = 1000000 / freq_mhz;
+
+ ret = create_timings_aligned(dmc, &dmc->timing_row[idx],
+ &dmc->timing_data[idx],
+ &dmc->timing_power[idx],
+ clk_period_ps);
+ }
+
+ of_node_put(np_ddr);
+
+ /* Take the highest frequency's timings as 'bypass' */
+ dmc->bypass_timing_row = dmc->timing_row[idx - 1];
+ dmc->bypass_timing_data = dmc->timing_data[idx - 1];
+ dmc->bypass_timing_power = dmc->timing_power[idx - 1];
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_init_clks() - Initialize clocks needed for DMC operation.
+ * @dmc: DMC structure containing needed fields
+ *
+ * Get the needed clocks defined in DT device, enable and set the right parents.
+ * Read current frequency and initialize the initial rate for governor.
+ */
+static int exynos5_dmc_init_clks(struct exynos5_dmc *dmc)
+{
+ int ret;
+ unsigned long target_volt = 0;
+ unsigned long target_rate = 0;
+ unsigned int tmp;
+
+ dmc->fout_spll = devm_clk_get(dmc->dev, "fout_spll");
+ if (IS_ERR(dmc->fout_spll))
+ return PTR_ERR(dmc->fout_spll);
+
+ dmc->fout_bpll = devm_clk_get(dmc->dev, "fout_bpll");
+ if (IS_ERR(dmc->fout_bpll))
+ return PTR_ERR(dmc->fout_bpll);
+
+ dmc->mout_mclk_cdrex = devm_clk_get(dmc->dev, "mout_mclk_cdrex");
+ if (IS_ERR(dmc->mout_mclk_cdrex))
+ return PTR_ERR(dmc->mout_mclk_cdrex);
+
+ dmc->mout_bpll = devm_clk_get(dmc->dev, "mout_bpll");
+ if (IS_ERR(dmc->mout_bpll))
+ return PTR_ERR(dmc->mout_bpll);
+
+ dmc->mout_mx_mspll_ccore = devm_clk_get(dmc->dev,
+ "mout_mx_mspll_ccore");
+ if (IS_ERR(dmc->mout_mx_mspll_ccore))
+ return PTR_ERR(dmc->mout_mx_mspll_ccore);
+
+ dmc->mout_spll = devm_clk_get(dmc->dev, "ff_dout_spll2");
+ if (IS_ERR(dmc->mout_spll)) {
+ dmc->mout_spll = devm_clk_get(dmc->dev, "mout_sclk_spll");
+ if (IS_ERR(dmc->mout_spll))
+ return PTR_ERR(dmc->mout_spll);
+ }
+
+ /*
+ * Convert frequency to KHz values and set it for the governor.
+ */
+ dmc->curr_rate = clk_get_rate(dmc->mout_mclk_cdrex);
+ dmc->curr_rate = exynos5_dmc_align_init_freq(dmc, dmc->curr_rate);
+ exynos5_dmc_df_profile.initial_freq = dmc->curr_rate;
+
+ ret = exynos5_dmc_get_volt_freq(dmc, &dmc->curr_rate, &target_rate,
+ &target_volt, 0);
+ if (ret)
+ return ret;
+
+ dmc->curr_volt = target_volt;
+
+ clk_set_parent(dmc->mout_mx_mspll_ccore, dmc->mout_spll);
+
+ dmc->bypass_rate = clk_get_rate(dmc->mout_mx_mspll_ccore);
+
+ clk_prepare_enable(dmc->fout_bpll);
+ clk_prepare_enable(dmc->mout_bpll);
+
+ /*
+ * Some bootloaders do not set clock routes correctly.
+ * Stop one path in clocks to PHY.
+ */
+ regmap_read(dmc->clk_regmap, CDREX_LPDDR3PHY_CLKM_SRC, &tmp);
+ tmp &= ~(BIT(1) | BIT(0));
+ regmap_write(dmc->clk_regmap, CDREX_LPDDR3PHY_CLKM_SRC, tmp);
+
+ return 0;
+}
+
+/**
+ * exynos5_performance_counters_init() - Initializes performance DMC's counters
+ * @dmc: DMC for which it does the setup
+ *
+ * Initialization of performance counters in DMC for estimating usage.
+ * The counter's values are used for calculation of a memory bandwidth and based
+ * on that the governor changes the frequency.
+ * The counters are not used when the governor is GOVERNOR_USERSPACE.
+ */
+static int exynos5_performance_counters_init(struct exynos5_dmc *dmc)
+{
+ int counters_size;
+ int ret, i;
+
+ dmc->num_counters = devfreq_event_get_edev_count(dmc->dev);
+ if (dmc->num_counters < 0) {
+ dev_err(dmc->dev, "could not get devfreq-event counters\n");
+ return dmc->num_counters;
+ }
+
+ counters_size = sizeof(struct devfreq_event_dev) * dmc->num_counters;
+ dmc->counter = devm_kzalloc(dmc->dev, counters_size, GFP_KERNEL);
+ if (!dmc->counter)
+ return -ENOMEM;
+
+ for (i = 0; i < dmc->num_counters; i++) {
+ dmc->counter[i] =
+ devfreq_event_get_edev_by_phandle(dmc->dev, i);
+ if (IS_ERR_OR_NULL(dmc->counter[i]))
+ return -EPROBE_DEFER;
+ }
+
+ ret = exynos5_counters_enable_edev(dmc);
+ if (ret < 0) {
+ dev_err(dmc->dev, "could not enable event counter\n");
+ return ret;
+ }
+
+ ret = exynos5_counters_set_event(dmc);
+ if (ret < 0) {
+ exynos5_counters_disable_edev(dmc);
+ dev_err(dmc->dev, "could not set event counter\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * exynos5_dmc_set_pause_on_switching() - Controls a pause feature in DMC
+ * @dmc: device which is used for changing this feature
+ * @set: a boolean state passing enable/disable request
+ *
+ * There is a need of pausing DREX DMC when divider or MUX in clock tree
+ * changes its configuration. In such situation access to the memory is blocked
+ * in DMC automatically. This feature is used when clock frequency change
+ * request appears and touches clock tree.
+ */
+static inline int exynos5_dmc_set_pause_on_switching(struct exynos5_dmc *dmc)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(dmc->clk_regmap, CDREX_PAUSE, &val);
+ if (ret)
+ return ret;
+
+ val |= 1UL;
+ regmap_write(dmc->clk_regmap, CDREX_PAUSE, val);
+
+ return 0;
+}
+
+static irqreturn_t dmc_irq_thread(int irq, void *priv)
+{
+ int res;
+ struct exynos5_dmc *dmc = priv;
+
+ mutex_lock(&dmc->df->lock);
+
+ exynos5_dmc_perf_events_check(dmc);
+
+ res = update_devfreq(dmc->df);
+ if (res)
+ dev_warn(dmc->dev, "devfreq failed with %d\n", res);
+
+ mutex_unlock(&dmc->df->lock);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * exynos5_dmc_probe() - Probe function for the DMC driver
+ * @pdev: platform device for which the driver is going to be initialized
+ *
+ * Initialize basic components: clocks, regulators, performance counters, etc.
+ * Read out product version and based on the information setup
+ * internal structures for the controller (frequency and voltage) and for DRAM
+ * memory parameters: timings for each operating frequency.
+ * Register new devfreq device for controlling DVFS of the DMC.
+ */
+static int exynos5_dmc_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct exynos5_dmc *dmc;
+ struct resource *res;
+ int irq[2];
+
+ dmc = devm_kzalloc(dev, sizeof(*dmc), GFP_KERNEL);
+ if (!dmc)
+ return -ENOMEM;
+
+ mutex_init(&dmc->lock);
+
+ dmc->dev = dev;
+ platform_set_drvdata(pdev, dmc);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ dmc->base_drexi0 = devm_ioremap_resource(dev, res);
+ if (IS_ERR(dmc->base_drexi0))
+ return PTR_ERR(dmc->base_drexi0);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ dmc->base_drexi1 = devm_ioremap_resource(dev, res);
+ if (IS_ERR(dmc->base_drexi1))
+ return PTR_ERR(dmc->base_drexi1);
+
+ dmc->clk_regmap = syscon_regmap_lookup_by_phandle(np,
+ "samsung,syscon-clk");
+ if (IS_ERR(dmc->clk_regmap))
+ return PTR_ERR(dmc->clk_regmap);
+
+ ret = exynos5_init_freq_table(dmc, &exynos5_dmc_df_profile);
+ if (ret) {
+ dev_warn(dev, "couldn't initialize frequency settings\n");
+ return ret;
+ }
+
+ dmc->vdd_mif = devm_regulator_get(dev, "vdd");
+ if (IS_ERR(dmc->vdd_mif)) {
+ ret = PTR_ERR(dmc->vdd_mif);
+ return ret;
+ }
+
+ ret = exynos5_dmc_init_clks(dmc);
+ if (ret)
+ return ret;
+
+ ret = of_get_dram_timings(dmc);
+ if (ret) {
+ dev_warn(dev, "couldn't initialize timings settings\n");
+ goto remove_clocks;
+ }
+
+ ret = exynos5_dmc_set_pause_on_switching(dmc);
+ if (ret) {
+ dev_warn(dev, "couldn't get access to PAUSE register\n");
+ goto remove_clocks;
+ }
+
+ /* There is two modes in which the driver works: polling or IRQ */
+ irq[0] = platform_get_irq_byname(pdev, "drex_0");
+ irq[1] = platform_get_irq_byname(pdev, "drex_1");
+ if (irq[0] > 0 && irq[1] > 0) {
+ ret = devm_request_threaded_irq(dev, irq[0], NULL,
+ dmc_irq_thread, IRQF_ONESHOT,
+ dev_name(dev), dmc);
+ if (ret) {
+ dev_err(dev, "couldn't grab IRQ\n");
+ goto remove_clocks;
+ }
+
+ ret = devm_request_threaded_irq(dev, irq[1], NULL,
+ dmc_irq_thread, IRQF_ONESHOT,
+ dev_name(dev), dmc);
+ if (ret) {
+ dev_err(dev, "couldn't grab IRQ\n");
+ goto remove_clocks;
+ }
+
+ /*
+ * Setup default thresholds for the devfreq governor.
+ * The values are chosen based on experiments.
+ */
+ dmc->gov_data.upthreshold = 55;
+ dmc->gov_data.downdifferential = 5;
+
+ exynos5_dmc_enable_perf_events(dmc);
+
+ dmc->in_irq_mode = 1;
+ } else {
+ ret = exynos5_performance_counters_init(dmc);
+ if (ret) {
+ dev_warn(dev, "couldn't probe performance counters\n");
+ goto remove_clocks;
+ }
+
+ /*
+ * Setup default thresholds for the devfreq governor.
+ * The values are chosen based on experiments.
+ */
+ dmc->gov_data.upthreshold = 30;
+ dmc->gov_data.downdifferential = 5;
+
+ exynos5_dmc_df_profile.polling_ms = 500;
+ }
+
+
+ dmc->df = devm_devfreq_add_device(dev, &exynos5_dmc_df_profile,
+ DEVFREQ_GOV_SIMPLE_ONDEMAND,
+ &dmc->gov_data);
+
+ if (IS_ERR(dmc->df)) {
+ ret = PTR_ERR(dmc->df);
+ goto err_devfreq_add;
+ }
+
+ if (dmc->in_irq_mode)
+ exynos5_dmc_start_perf_events(dmc, PERF_COUNTER_START_VALUE);
+
+ dev_info(dev, "DMC initialized\n");
+
+ return 0;
+
+err_devfreq_add:
+ if (dmc->in_irq_mode)
+ exynos5_dmc_disable_perf_events(dmc);
+ else
+ exynos5_counters_disable_edev(dmc);
+remove_clocks:
+ clk_disable_unprepare(dmc->mout_bpll);
+ clk_disable_unprepare(dmc->fout_bpll);
+
+ return ret;
+}
+
+/**
+ * exynos5_dmc_remove() - Remove function for the platform device
+ * @pdev: platform device which is going to be removed
+ *
+ * The function relies on 'devm' framework function which automatically
+ * clean the device's resources. It just calls explicitly disable function for
+ * the performance counters.
+ */
+static int exynos5_dmc_remove(struct platform_device *pdev)
+{
+ struct exynos5_dmc *dmc = dev_get_drvdata(&pdev->dev);
+
+ if (dmc->in_irq_mode)
+ exynos5_dmc_disable_perf_events(dmc);
+ else
+ exynos5_counters_disable_edev(dmc);
+
+ clk_disable_unprepare(dmc->mout_bpll);
+ clk_disable_unprepare(dmc->fout_bpll);
+
+ dev_pm_opp_remove_table(dmc->dev);
+
+ return 0;
+}
+
+static const struct of_device_id exynos5_dmc_of_match[] = {
+ { .compatible = "samsung,exynos5422-dmc", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, exynos5_dmc_of_match);
+
+static struct platform_driver exynos5_dmc_platdrv = {
+ .probe = exynos5_dmc_probe,
+ .remove = exynos5_dmc_remove,
+ .driver = {
+ .name = "exynos5-dmc",
+ .of_match_table = exynos5_dmc_of_match,
+ },
+};
+module_platform_driver(exynos5_dmc_platdrv);
+MODULE_DESCRIPTION("Driver for Exynos5422 Dynamic Memory Controller dynamic frequency and voltage change");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Lukasz Luba");
generated by cgit (git 2.34.1) at 2024-06-24 02:42:28 +0000