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authorLinus Walleij <linus.walleij@linaro.org>2019-10-26 23:47:32 +0200
committerLee Jones <lee.jones@linaro.org>2019-11-11 08:45:04 +0000
commit22fb3ad0cc5f578398953ddcab9c8239a08caccd (patch)
treead7ac7fab95c75124bc4471b735f282e3ed3b520
parent59dbc0e0d498c8bdb26a661ee080ee8d147c3c5d (diff)
mfd: db8500-prcmu: Support U8420-sysclk firmware
There is a distinct version of the Ux500 U8420 variant with "sysclk", as can be seen from the vendor code that didn't make it upstream, this firmware lacks the ULPPLL (ultra-low power phase locked loop) which in effect means that the timer clock is instead wired to the 32768 Hz always-on clock. This has some repercussions when enabling the timer clock as the code as it stands will disable the timer clock on these platforms (lacking the so-called "doze mode") and obtaining the wrong rate of the timer clock. The timer frequency is of course needed very early in the boot, and as a consequence, we need to shuffle around the early PRCMU init code: whereas in the past we did not need to look up the PRCMU firmware version in the early init, but now we need to know the version before the core system timers are registered so we restructure the platform callbacks to the PRCMU so as not to take any arguments and instead look up the resources it needs directly from the device tree when initializing. As we do not yet support any platforms using this firmware it is not a regression, but as PostmarketOS is starting to support products with this firmware we need to fix this up. The low rate of 32kHz also makes the MTU timer unsuitable as delay timer but this needs to be fixed in a separate patch. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Stephan Gerhold <stephan@gerhold.net> Acked-by: Olof Johansson <olof@lixom.net> Signed-off-by: Lee Jones <lee.jones@linaro.org>
-rw-r--r--arch/arm/mach-ux500/cpu-db8500.c2
-rw-r--r--drivers/mfd/db8500-prcmu.c63
-rw-r--r--include/linux/mfd/db8500-prcmu.h4
-rw-r--r--include/linux/mfd/dbx500-prcmu.h7
4 files changed, 50 insertions, 26 deletions
diff --git a/arch/arm/mach-ux500/cpu-db8500.c b/arch/arm/mach-ux500/cpu-db8500.c
index 3875027ef8fc..e929aaa744c0 100644
--- a/arch/arm/mach-ux500/cpu-db8500.c
+++ b/arch/arm/mach-ux500/cpu-db8500.c
@@ -84,6 +84,7 @@ static void __init ux500_init_irq(void)
struct resource r;
irqchip_init();
+ prcmu_early_init();
np = of_find_compatible_node(NULL, NULL, "stericsson,db8500-prcmu");
of_address_to_resource(np, 0, &r);
of_node_put(np);
@@ -91,7 +92,6 @@ static void __init ux500_init_irq(void)
pr_err("could not find PRCMU base resource\n");
return;
}
- prcmu_early_init(r.start, r.end-r.start);
ux500_pm_init(r.start, r.end-r.start);
/* Unlock before init */
diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
index 3972f910dd23..57ac58b4b5f3 100644
--- a/drivers/mfd/db8500-prcmu.c
+++ b/drivers/mfd/db8500-prcmu.c
@@ -27,6 +27,7 @@
#include <linux/bitops.h>
#include <linux/fs.h>
#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
@@ -668,6 +669,14 @@ struct prcmu_fw_version *prcmu_get_fw_version(void)
return fw_info.valid ? &fw_info.version : NULL;
}
+static bool prcmu_is_ulppll_disabled(void)
+{
+ struct prcmu_fw_version *ver;
+
+ ver = prcmu_get_fw_version();
+ return ver && ver->project == PRCMU_FW_PROJECT_U8420_SYSCLK;
+}
+
bool prcmu_has_arm_maxopp(void)
{
return (readb(tcdm_base + PRCM_AVS_VARM_MAX_OPP) &
@@ -1308,10 +1317,23 @@ static int request_sysclk(bool enable)
static int request_timclk(bool enable)
{
- u32 val = (PRCM_TCR_DOZE_MODE | PRCM_TCR_TENSEL_MASK);
+ u32 val;
+
+ /*
+ * On the U8420_CLKSEL firmware, the ULP (Ultra Low Power)
+ * PLL is disabled so we cannot use doze mode, this will
+ * stop the clock on this firmware.
+ */
+ if (prcmu_is_ulppll_disabled())
+ val = 0;
+ else
+ val = (PRCM_TCR_DOZE_MODE | PRCM_TCR_TENSEL_MASK);
if (!enable)
- val |= PRCM_TCR_STOP_TIMERS;
+ val |= PRCM_TCR_STOP_TIMERS |
+ PRCM_TCR_DOZE_MODE |
+ PRCM_TCR_TENSEL_MASK;
+
writel(val, PRCM_TCR);
return 0;
@@ -1615,7 +1637,8 @@ unsigned long prcmu_clock_rate(u8 clock)
if (clock < PRCMU_NUM_REG_CLOCKS)
return clock_rate(clock);
else if (clock == PRCMU_TIMCLK)
- return ROOT_CLOCK_RATE / 16;
+ return prcmu_is_ulppll_disabled() ?
+ 32768 : ROOT_CLOCK_RATE / 16;
else if (clock == PRCMU_SYSCLK)
return ROOT_CLOCK_RATE;
else if (clock == PRCMU_PLLSOC0)
@@ -2646,6 +2669,8 @@ static char *fw_project_name(u32 project)
return "U8520 MBL";
case PRCMU_FW_PROJECT_U8420:
return "U8420";
+ case PRCMU_FW_PROJECT_U8420_SYSCLK:
+ return "U8420-sysclk";
case PRCMU_FW_PROJECT_U9540:
return "U9540";
case PRCMU_FW_PROJECT_A9420:
@@ -2693,27 +2718,18 @@ static int db8500_irq_init(struct device_node *np)
return 0;
}
-static void dbx500_fw_version_init(struct platform_device *pdev,
- u32 version_offset)
+static void dbx500_fw_version_init(struct device_node *np)
{
- struct resource *res;
void __iomem *tcpm_base;
u32 version;
- res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
- "prcmu-tcpm");
- if (!res) {
- dev_err(&pdev->dev,
- "Error: no prcmu tcpm memory region provided\n");
- return;
- }
- tcpm_base = ioremap(res->start, resource_size(res));
+ tcpm_base = of_iomap(np, 1);
if (!tcpm_base) {
- dev_err(&pdev->dev, "no prcmu tcpm mem region provided\n");
+ pr_err("no prcmu tcpm mem region provided\n");
return;
}
- version = readl(tcpm_base + version_offset);
+ version = readl(tcpm_base + DB8500_PRCMU_FW_VERSION_OFFSET);
fw_info.version.project = (version & 0xFF);
fw_info.version.api_version = (version >> 8) & 0xFF;
fw_info.version.func_version = (version >> 16) & 0xFF;
@@ -2731,7 +2747,7 @@ static void dbx500_fw_version_init(struct platform_device *pdev,
iounmap(tcpm_base);
}
-void __init db8500_prcmu_early_init(u32 phy_base, u32 size)
+void __init db8500_prcmu_early_init(void)
{
/*
* This is a temporary remap to bring up the clocks. It is
@@ -2740,9 +2756,17 @@ void __init db8500_prcmu_early_init(u32 phy_base, u32 size)
* clock driver can probe independently. An early initcall will
* still be needed, but it can be diverted into drivers/clk/ux500.
*/
- prcmu_base = ioremap(phy_base, size);
- if (!prcmu_base)
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "stericsson,db8500-prcmu");
+ prcmu_base = of_iomap(np, 0);
+ if (!prcmu_base) {
+ of_node_put(np);
pr_err("%s: ioremap() of prcmu registers failed!\n", __func__);
+ return;
+ }
+ dbx500_fw_version_init(np);
+ of_node_put(np);
spin_lock_init(&mb0_transfer.lock);
spin_lock_init(&mb0_transfer.dbb_irqs_lock);
@@ -3084,7 +3108,6 @@ static int db8500_prcmu_probe(struct platform_device *pdev)
return -ENOMEM;
}
init_prcm_registers();
- dbx500_fw_version_init(pdev, DB8500_PRCMU_FW_VERSION_OFFSET);
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "prcmu-tcdm");
if (!res) {
dev_err(&pdev->dev, "no prcmu tcdm region provided\n");
diff --git a/include/linux/mfd/db8500-prcmu.h b/include/linux/mfd/db8500-prcmu.h
index 813710aa2cfd..1fc75d2b4a38 100644
--- a/include/linux/mfd/db8500-prcmu.h
+++ b/include/linux/mfd/db8500-prcmu.h
@@ -489,7 +489,7 @@ struct prcmu_auto_pm_config {
#ifdef CONFIG_MFD_DB8500_PRCMU
-void db8500_prcmu_early_init(u32 phy_base, u32 size);
+void db8500_prcmu_early_init(void);
int prcmu_set_rc_a2p(enum romcode_write);
enum romcode_read prcmu_get_rc_p2a(void);
enum ap_pwrst prcmu_get_xp70_current_state(void);
@@ -546,7 +546,7 @@ void db8500_prcmu_write_masked(unsigned int reg, u32 mask, u32 value);
#else /* !CONFIG_MFD_DB8500_PRCMU */
-static inline void db8500_prcmu_early_init(u32 phy_base, u32 size) {}
+static inline void db8500_prcmu_early_init(void) {}
static inline int prcmu_set_rc_a2p(enum romcode_write code)
{
diff --git a/include/linux/mfd/dbx500-prcmu.h b/include/linux/mfd/dbx500-prcmu.h
index 238401a50d0b..e2571040c7e8 100644
--- a/include/linux/mfd/dbx500-prcmu.h
+++ b/include/linux/mfd/dbx500-prcmu.h
@@ -190,6 +190,7 @@ enum ddr_pwrst {
#define PRCMU_FW_PROJECT_U8500_MBL2 12 /* Customer specific */
#define PRCMU_FW_PROJECT_U8520 13
#define PRCMU_FW_PROJECT_U8420 14
+#define PRCMU_FW_PROJECT_U8420_SYSCLK 17
#define PRCMU_FW_PROJECT_A9420 20
/* [32..63] 9540 and derivatives */
#define PRCMU_FW_PROJECT_U9540 32
@@ -211,9 +212,9 @@ struct prcmu_fw_version {
#if defined(CONFIG_UX500_SOC_DB8500)
-static inline void prcmu_early_init(u32 phy_base, u32 size)
+static inline void prcmu_early_init(void)
{
- return db8500_prcmu_early_init(phy_base, size);
+ return db8500_prcmu_early_init();
}
static inline int prcmu_set_power_state(u8 state, bool keep_ulp_clk,
@@ -401,7 +402,7 @@ static inline int prcmu_config_a9wdog(u8 num, bool sleep_auto_off)
}
#else
-static inline void prcmu_early_init(u32 phy_base, u32 size) {}
+static inline void prcmu_early_init(void) {}
static inline int prcmu_set_power_state(u8 state, bool keep_ulp_clk,
bool keep_ap_pll)