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path: root/drivers/clk/qcom/ipq-cmn-pll.c
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-rw-r--r--drivers/clk/qcom/ipq-cmn-pll.c435
1 files changed, 435 insertions, 0 deletions
diff --git a/drivers/clk/qcom/ipq-cmn-pll.c b/drivers/clk/qcom/ipq-cmn-pll.c
new file mode 100644
index 000000000000..432d4c4b7aa6
--- /dev/null
+++ b/drivers/clk/qcom/ipq-cmn-pll.c
@@ -0,0 +1,435 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+/*
+ * CMN PLL block expects the reference clock from on-board Wi-Fi block,
+ * and supplies fixed rate clocks as output to the networking hardware
+ * blocks and to GCC. The networking related blocks include PPE (packet
+ * process engine), the externally connected PHY or switch devices, and
+ * the PCS.
+ *
+ * On the IPQ9574 SoC, there are three clocks with 50 MHZ and one clock
+ * with 25 MHZ which are output from the CMN PLL to Ethernet PHY (or switch),
+ * and one clock with 353 MHZ to PPE. The other fixed rate output clocks
+ * are supplied to GCC (24 MHZ as XO and 32 KHZ as sleep clock), and to PCS
+ * with 31.25 MHZ.
+ *
+ * +---------+
+ * | GCC |
+ * +--+---+--+
+ * AHB CLK| |SYS CLK
+ * V V
+ * +-------+---+------+
+ * | +-------------> eth0-50mhz
+ * REF CLK | IPQ9574 |
+ * -------->+ +-------------> eth1-50mhz
+ * | CMN PLL block |
+ * | +-------------> eth2-50mhz
+ * | |
+ * +----+----+----+---+-------------> eth-25mhz
+ * | | |
+ * V V V
+ * GCC PCS NSS/PPE
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_clock.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+
+#include <dt-bindings/clock/qcom,ipq-cmn-pll.h>
+
+#define CMN_PLL_REFCLK_SRC_SELECTION 0x28
+#define CMN_PLL_REFCLK_SRC_DIV GENMASK(9, 8)
+
+#define CMN_PLL_LOCKED 0x64
+#define CMN_PLL_CLKS_LOCKED BIT(8)
+
+#define CMN_PLL_POWER_ON_AND_RESET 0x780
+#define CMN_ANA_EN_SW_RSTN BIT(6)
+
+#define CMN_PLL_REFCLK_CONFIG 0x784
+#define CMN_PLL_REFCLK_EXTERNAL BIT(9)
+#define CMN_PLL_REFCLK_DIV GENMASK(8, 4)
+#define CMN_PLL_REFCLK_INDEX GENMASK(3, 0)
+
+#define CMN_PLL_CTRL 0x78c
+#define CMN_PLL_CTRL_LOCK_DETECT_EN BIT(15)
+
+#define CMN_PLL_DIVIDER_CTRL 0x794
+#define CMN_PLL_DIVIDER_CTRL_FACTOR GENMASK(9, 0)
+
+/**
+ * struct cmn_pll_fixed_output_clk - CMN PLL output clocks information
+ * @id: Clock specifier to be supplied
+ * @name: Clock name to be registered
+ * @rate: Clock rate
+ */
+struct cmn_pll_fixed_output_clk {
+ unsigned int id;
+ const char *name;
+ unsigned long rate;
+};
+
+/**
+ * struct clk_cmn_pll - CMN PLL hardware specific data
+ * @regmap: hardware regmap.
+ * @hw: handle between common and hardware-specific interfaces
+ */
+struct clk_cmn_pll {
+ struct regmap *regmap;
+ struct clk_hw hw;
+};
+
+#define CLK_PLL_OUTPUT(_id, _name, _rate) { \
+ .id = _id, \
+ .name = _name, \
+ .rate = _rate, \
+}
+
+#define to_clk_cmn_pll(_hw) container_of(_hw, struct clk_cmn_pll, hw)
+
+static const struct regmap_config ipq_cmn_pll_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .max_register = 0x7fc,
+ .fast_io = true,
+};
+
+static const struct cmn_pll_fixed_output_clk ipq9574_output_clks[] = {
+ CLK_PLL_OUTPUT(XO_24MHZ_CLK, "xo-24mhz", 24000000UL),
+ CLK_PLL_OUTPUT(SLEEP_32KHZ_CLK, "sleep-32khz", 32000UL),
+ CLK_PLL_OUTPUT(PCS_31P25MHZ_CLK, "pcs-31p25mhz", 31250000UL),
+ CLK_PLL_OUTPUT(NSS_1200MHZ_CLK, "nss-1200mhz", 1200000000UL),
+ CLK_PLL_OUTPUT(PPE_353MHZ_CLK, "ppe-353mhz", 353000000UL),
+ CLK_PLL_OUTPUT(ETH0_50MHZ_CLK, "eth0-50mhz", 50000000UL),
+ CLK_PLL_OUTPUT(ETH1_50MHZ_CLK, "eth1-50mhz", 50000000UL),
+ CLK_PLL_OUTPUT(ETH2_50MHZ_CLK, "eth2-50mhz", 50000000UL),
+ CLK_PLL_OUTPUT(ETH_25MHZ_CLK, "eth-25mhz", 25000000UL),
+};
+
+/*
+ * CMN PLL has the single parent clock, which supports the several
+ * possible parent clock rates, each parent clock rate is reflected
+ * by the specific reference index value in the hardware.
+ */
+static int ipq_cmn_pll_find_freq_index(unsigned long parent_rate)
+{
+ int index = -EINVAL;
+
+ switch (parent_rate) {
+ case 25000000:
+ index = 3;
+ break;
+ case 31250000:
+ index = 4;
+ break;
+ case 40000000:
+ index = 6;
+ break;
+ case 48000000:
+ case 96000000:
+ /*
+ * Parent clock rate 48 MHZ and 96 MHZ take the same value
+ * of reference clock index. 96 MHZ needs the source clock
+ * divider to be programmed as 2.
+ */
+ index = 7;
+ break;
+ case 50000000:
+ index = 8;
+ break;
+ default:
+ break;
+ }
+
+ return index;
+}
+
+static unsigned long clk_cmn_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_cmn_pll *cmn_pll = to_clk_cmn_pll(hw);
+ u32 val, factor;
+
+ /*
+ * The value of CMN_PLL_DIVIDER_CTRL_FACTOR is automatically adjusted
+ * by HW according to the parent clock rate.
+ */
+ regmap_read(cmn_pll->regmap, CMN_PLL_DIVIDER_CTRL, &val);
+ factor = FIELD_GET(CMN_PLL_DIVIDER_CTRL_FACTOR, val);
+
+ return parent_rate * 2 * factor;
+}
+
+static int clk_cmn_pll_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ int ret;
+
+ /* Validate the rate of the single parent clock. */
+ ret = ipq_cmn_pll_find_freq_index(req->best_parent_rate);
+
+ return ret < 0 ? ret : 0;
+}
+
+/*
+ * This function is used to initialize the CMN PLL to enable the fixed
+ * rate output clocks. It is expected to be configured once.
+ */
+static int clk_cmn_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_cmn_pll *cmn_pll = to_clk_cmn_pll(hw);
+ int ret, index;
+ u32 val;
+
+ /*
+ * Configure the reference input clock selection as per the given
+ * parent clock. The output clock rates are always of fixed value.
+ */
+ index = ipq_cmn_pll_find_freq_index(parent_rate);
+ if (index < 0)
+ return index;
+
+ ret = regmap_update_bits(cmn_pll->regmap, CMN_PLL_REFCLK_CONFIG,
+ CMN_PLL_REFCLK_INDEX,
+ FIELD_PREP(CMN_PLL_REFCLK_INDEX, index));
+ if (ret)
+ return ret;
+
+ /*
+ * Update the source clock rate selection and source clock
+ * divider as 2 when the parent clock rate is 96 MHZ.
+ */
+ if (parent_rate == 96000000) {
+ ret = regmap_update_bits(cmn_pll->regmap, CMN_PLL_REFCLK_CONFIG,
+ CMN_PLL_REFCLK_DIV,
+ FIELD_PREP(CMN_PLL_REFCLK_DIV, 2));
+ if (ret)
+ return ret;
+
+ ret = regmap_update_bits(cmn_pll->regmap, CMN_PLL_REFCLK_SRC_SELECTION,
+ CMN_PLL_REFCLK_SRC_DIV,
+ FIELD_PREP(CMN_PLL_REFCLK_SRC_DIV, 0));
+ if (ret)
+ return ret;
+ }
+
+ /* Enable PLL locked detect. */
+ ret = regmap_set_bits(cmn_pll->regmap, CMN_PLL_CTRL,
+ CMN_PLL_CTRL_LOCK_DETECT_EN);
+ if (ret)
+ return ret;
+
+ /*
+ * Reset the CMN PLL block to ensure the updated configurations
+ * take effect.
+ */
+ ret = regmap_clear_bits(cmn_pll->regmap, CMN_PLL_POWER_ON_AND_RESET,
+ CMN_ANA_EN_SW_RSTN);
+ if (ret)
+ return ret;
+
+ usleep_range(1000, 1200);
+ ret = regmap_set_bits(cmn_pll->regmap, CMN_PLL_POWER_ON_AND_RESET,
+ CMN_ANA_EN_SW_RSTN);
+ if (ret)
+ return ret;
+
+ /* Stability check of CMN PLL output clocks. */
+ return regmap_read_poll_timeout(cmn_pll->regmap, CMN_PLL_LOCKED, val,
+ (val & CMN_PLL_CLKS_LOCKED),
+ 100, 100 * USEC_PER_MSEC);
+}
+
+static const struct clk_ops clk_cmn_pll_ops = {
+ .recalc_rate = clk_cmn_pll_recalc_rate,
+ .determine_rate = clk_cmn_pll_determine_rate,
+ .set_rate = clk_cmn_pll_set_rate,
+};
+
+static struct clk_hw *ipq_cmn_pll_clk_hw_register(struct platform_device *pdev)
+{
+ struct clk_parent_data pdata = { .index = 0 };
+ struct device *dev = &pdev->dev;
+ struct clk_init_data init = {};
+ struct clk_cmn_pll *cmn_pll;
+ struct regmap *regmap;
+ void __iomem *base;
+ int ret;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return ERR_CAST(base);
+
+ regmap = devm_regmap_init_mmio(dev, base, &ipq_cmn_pll_regmap_config);
+ if (IS_ERR(regmap))
+ return ERR_CAST(regmap);
+
+ cmn_pll = devm_kzalloc(dev, sizeof(*cmn_pll), GFP_KERNEL);
+ if (!cmn_pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = "cmn_pll";
+ init.parent_data = &pdata;
+ init.num_parents = 1;
+ init.ops = &clk_cmn_pll_ops;
+
+ cmn_pll->hw.init = &init;
+ cmn_pll->regmap = regmap;
+
+ ret = devm_clk_hw_register(dev, &cmn_pll->hw);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return &cmn_pll->hw;
+}
+
+static int ipq_cmn_pll_register_clks(struct platform_device *pdev)
+{
+ const struct cmn_pll_fixed_output_clk *fixed_clk;
+ struct clk_hw_onecell_data *hw_data;
+ struct device *dev = &pdev->dev;
+ struct clk_hw *cmn_pll_hw;
+ unsigned int num_clks;
+ struct clk_hw *hw;
+ int ret, i;
+
+ fixed_clk = ipq9574_output_clks;
+ num_clks = ARRAY_SIZE(ipq9574_output_clks);
+
+ hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, num_clks + 1),
+ GFP_KERNEL);
+ if (!hw_data)
+ return -ENOMEM;
+
+ /*
+ * Register the CMN PLL clock, which is the parent clock of
+ * the fixed rate output clocks.
+ */
+ cmn_pll_hw = ipq_cmn_pll_clk_hw_register(pdev);
+ if (IS_ERR(cmn_pll_hw))
+ return PTR_ERR(cmn_pll_hw);
+
+ /* Register the fixed rate output clocks. */
+ for (i = 0; i < num_clks; i++) {
+ hw = clk_hw_register_fixed_rate_parent_hw(dev, fixed_clk[i].name,
+ cmn_pll_hw, 0,
+ fixed_clk[i].rate);
+ if (IS_ERR(hw)) {
+ ret = PTR_ERR(hw);
+ goto unregister_fixed_clk;
+ }
+
+ hw_data->hws[fixed_clk[i].id] = hw;
+ }
+
+ /*
+ * Provide the CMN PLL clock. The clock rate of CMN PLL
+ * is configured to 12 GHZ by DT property assigned-clock-rates-u64.
+ */
+ hw_data->hws[CMN_PLL_CLK] = cmn_pll_hw;
+ hw_data->num = num_clks + 1;
+
+ ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, hw_data);
+ if (ret)
+ goto unregister_fixed_clk;
+
+ platform_set_drvdata(pdev, hw_data);
+
+ return 0;
+
+unregister_fixed_clk:
+ while (i > 0)
+ clk_hw_unregister(hw_data->hws[fixed_clk[--i].id]);
+
+ return ret;
+}
+
+static int ipq_cmn_pll_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ ret = devm_pm_runtime_enable(dev);
+ if (ret)
+ return ret;
+
+ ret = devm_pm_clk_create(dev);
+ if (ret)
+ return ret;
+
+ /*
+ * To access the CMN PLL registers, the GCC AHB & SYS clocks
+ * of CMN PLL block need to be enabled.
+ */
+ ret = pm_clk_add(dev, "ahb");
+ if (ret)
+ return dev_err_probe(dev, ret, "Fail to add AHB clock\n");
+
+ ret = pm_clk_add(dev, "sys");
+ if (ret)
+ return dev_err_probe(dev, ret, "Fail to add SYS clock\n");
+
+ ret = pm_runtime_resume_and_get(dev);
+ if (ret)
+ return ret;
+
+ /* Register CMN PLL clock and fixed rate output clocks. */
+ ret = ipq_cmn_pll_register_clks(pdev);
+ pm_runtime_put(dev);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Fail to register CMN PLL clocks\n");
+
+ return 0;
+}
+
+static void ipq_cmn_pll_clk_remove(struct platform_device *pdev)
+{
+ struct clk_hw_onecell_data *hw_data = platform_get_drvdata(pdev);
+ int i;
+
+ /*
+ * The clock with index CMN_PLL_CLK is unregistered by
+ * device management.
+ */
+ for (i = 0; i < hw_data->num; i++) {
+ if (i != CMN_PLL_CLK)
+ clk_hw_unregister(hw_data->hws[i]);
+ }
+}
+
+static const struct dev_pm_ops ipq_cmn_pll_pm_ops = {
+ SET_RUNTIME_PM_OPS(pm_clk_suspend, pm_clk_resume, NULL)
+};
+
+static const struct of_device_id ipq_cmn_pll_clk_ids[] = {
+ { .compatible = "qcom,ipq9574-cmn-pll", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ipq_cmn_pll_clk_ids);
+
+static struct platform_driver ipq_cmn_pll_clk_driver = {
+ .probe = ipq_cmn_pll_clk_probe,
+ .remove = ipq_cmn_pll_clk_remove,
+ .driver = {
+ .name = "ipq_cmn_pll",
+ .of_match_table = ipq_cmn_pll_clk_ids,
+ .pm = &ipq_cmn_pll_pm_ops,
+ },
+};
+module_platform_driver(ipq_cmn_pll_clk_driver);
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPQ CMN PLL Driver");
+MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2025-04-24 16:10:53 +0000