[PATCH v4 3/3] clk: samsung: exynos5433: Extract PM support to common ARM64 layer

From: Sam Protsenko
Date: Mon Mar 06 2023 - 19:24:43 EST


Exynos5433 clock driver implements PM support internally, which might be
also useful for other Exynos clock drivers. Extract all PM related code
from clk-exynos5433 to common ARM64 functions.

Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
---
Changes in v4:
- Rebased on top of krzk/linux.git/for-next tree
- Reworked exynos_arm64_enable_bus_clk() user code to only print an
error message if that function fails

Changes in v3:
- Rebased on top of latest soc/for-next tree
- Added Marek's Acked-by tag
- Added Marek's authorship in the header comment

Changes in v2:
- Rebased on top of latest soc/for-next tree
- Included linux/slab.h for kfree (found by kernel test robot)

drivers/clk/samsung/clk-exynos-arm64.c | 176 ++++++++++++++++++++++++-
drivers/clk/samsung/clk-exynos-arm64.h | 3 +
drivers/clk/samsung/clk-exynos5433.c | 157 +---------------------
3 files changed, 180 insertions(+), 156 deletions(-)

diff --git a/drivers/clk/samsung/clk-exynos-arm64.c b/drivers/clk/samsung/clk-exynos-arm64.c
index 60fd820c14aa..7d8937caf22a 100644
--- a/drivers/clk/samsung/clk-exynos-arm64.c
+++ b/drivers/clk/samsung/clk-exynos-arm64.c
@@ -10,6 +10,9 @@
*/
#include <linux/clk.h>
#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>

#include "clk-exynos-arm64.h"

@@ -21,6 +24,19 @@
#define GATE_OFF_START 0x2000
#define GATE_OFF_END 0x2fff

+struct exynos_arm64_cmu_data {
+ struct samsung_clk_reg_dump *clk_save;
+ unsigned int nr_clk_save;
+ const struct samsung_clk_reg_dump *clk_suspend;
+ unsigned int nr_clk_suspend;
+
+ struct clk *clk;
+ struct clk **pclks;
+ int nr_pclks;
+
+ struct samsung_clk_provider *ctx;
+};
+
/**
* exynos_arm64_init_clocks - Set clocks initial configuration
* @np: CMU device tree node with "reg" property (CMU addr)
@@ -76,10 +92,16 @@ static int __init exynos_arm64_enable_bus_clk(struct device *dev,
if (!cmu->clk_name)
return 0;

- if (dev)
+ if (dev) {
+ struct exynos_arm64_cmu_data *data;
+
parent_clk = clk_get(dev, cmu->clk_name);
- else
+ data = dev_get_drvdata(dev);
+ if (data)
+ data->clk = parent_clk;
+ } else {
parent_clk = of_clk_get_by_name(np, cmu->clk_name);
+ }

if (IS_ERR(parent_clk))
return PTR_ERR(parent_clk);
@@ -87,6 +109,46 @@ static int __init exynos_arm64_enable_bus_clk(struct device *dev,
return clk_prepare_enable(parent_clk);
}

+static int __init exynos_arm64_cmu_prepare_pm(struct device *dev,
+ const struct samsung_cmu_info *cmu)
+{
+ struct exynos_arm64_cmu_data *data = dev_get_drvdata(dev);
+ int i;
+
+ data->clk_save = samsung_clk_alloc_reg_dump(cmu->clk_regs,
+ cmu->nr_clk_regs);
+ if (!data->clk_save)
+ return -ENOMEM;
+
+ data->nr_clk_save = cmu->nr_clk_regs;
+ data->clk_suspend = cmu->suspend_regs;
+ data->nr_clk_suspend = cmu->nr_suspend_regs;
+ data->nr_pclks = of_clk_get_parent_count(dev->of_node);
+ if (!data->nr_pclks)
+ return 0;
+
+ data->pclks = devm_kcalloc(dev, sizeof(struct clk *), data->nr_pclks,
+ GFP_KERNEL);
+ if (!data->pclks) {
+ kfree(data->clk_save);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < data->nr_pclks; i++) {
+ struct clk *clk = of_clk_get(dev->of_node, i);
+
+ if (IS_ERR(clk)) {
+ kfree(data->clk_save);
+ while (--i >= 0)
+ clk_put(data->pclks[i]);
+ return PTR_ERR(clk);
+ }
+ data->pclks[i] = clk;
+ }
+
+ return 0;
+}
+
/**
* exynos_arm64_register_cmu - Register specified Exynos CMU domain
* @dev: Device object; may be NULL if this function is not being
@@ -117,3 +179,113 @@ void __init exynos_arm64_register_cmu(struct device *dev,
exynos_arm64_init_clocks(np, cmu->clk_regs, cmu->nr_clk_regs);
samsung_cmu_register_one(np, cmu);
}
+
+/**
+ * exynos_arm64_register_cmu_pm - Register Exynos CMU domain with PM support
+ *
+ * @pdev: Platform device object
+ * @set_manual: If true, set gate clocks to manual mode
+ *
+ * It's a version of exynos_arm64_register_cmu() with PM support. Should be
+ * called from probe function of platform driver.
+ *
+ * Return: 0 on success, or negative error code on error.
+ */
+int __init exynos_arm64_register_cmu_pm(struct platform_device *pdev,
+ bool set_manual)
+{
+ const struct samsung_cmu_info *cmu;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct exynos_arm64_cmu_data *data;
+ void __iomem *reg_base;
+ int ret;
+
+ cmu = of_device_get_match_data(dev);
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, data);
+
+ ret = exynos_arm64_cmu_prepare_pm(dev, cmu);
+ if (ret)
+ return ret;
+
+ /*
+ * Try to boot even if the parent clock enablement fails, as it might be
+ * already enabled by bootloader.
+ */
+ ret = exynos_arm64_enable_bus_clk(dev, NULL, cmu);
+ if (ret)
+ dev_err(dev, "%s: could not enable bus clock %s; err = %d\n",
+ __func__, cmu->clk_name, ret);
+
+ if (set_manual)
+ exynos_arm64_init_clocks(np, cmu->clk_regs, cmu->nr_clk_regs);
+
+ reg_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(reg_base))
+ return PTR_ERR(reg_base);
+
+ data->ctx = samsung_clk_init(dev, reg_base, cmu->nr_clk_ids);
+
+ /*
+ * Enable runtime PM here to allow the clock core using runtime PM
+ * for the registered clocks. Additionally, we increase the runtime
+ * PM usage count before registering the clocks, to prevent the
+ * clock core from runtime suspending the device.
+ */
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
+ samsung_cmu_register_clocks(data->ctx, cmu);
+ samsung_clk_of_add_provider(dev->of_node, data->ctx);
+ pm_runtime_put_sync(dev);
+
+ return 0;
+}
+
+int exynos_arm64_cmu_suspend(struct device *dev)
+{
+ struct exynos_arm64_cmu_data *data = dev_get_drvdata(dev);
+ int i;
+
+ samsung_clk_save(data->ctx->reg_base, data->clk_save,
+ data->nr_clk_save);
+
+ for (i = 0; i < data->nr_pclks; i++)
+ clk_prepare_enable(data->pclks[i]);
+
+ /* For suspend some registers have to be set to certain values */
+ samsung_clk_restore(data->ctx->reg_base, data->clk_suspend,
+ data->nr_clk_suspend);
+
+ for (i = 0; i < data->nr_pclks; i++)
+ clk_disable_unprepare(data->pclks[i]);
+
+ clk_disable_unprepare(data->clk);
+
+ return 0;
+}
+
+int exynos_arm64_cmu_resume(struct device *dev)
+{
+ struct exynos_arm64_cmu_data *data = dev_get_drvdata(dev);
+ int i;
+
+ clk_prepare_enable(data->clk);
+
+ for (i = 0; i < data->nr_pclks; i++)
+ clk_prepare_enable(data->pclks[i]);
+
+ samsung_clk_restore(data->ctx->reg_base, data->clk_save,
+ data->nr_clk_save);
+
+ for (i = 0; i < data->nr_pclks; i++)
+ clk_disable_unprepare(data->pclks[i]);
+
+ return 0;
+}
diff --git a/drivers/clk/samsung/clk-exynos-arm64.h b/drivers/clk/samsung/clk-exynos-arm64.h
index 0dd174693935..969979e714bc 100644
--- a/drivers/clk/samsung/clk-exynos-arm64.h
+++ b/drivers/clk/samsung/clk-exynos-arm64.h
@@ -16,5 +16,8 @@

void exynos_arm64_register_cmu(struct device *dev,
struct device_node *np, const struct samsung_cmu_info *cmu);
+int exynos_arm64_register_cmu_pm(struct platform_device *pdev, bool set_manual);
+int exynos_arm64_cmu_suspend(struct device *dev);
+int exynos_arm64_cmu_resume(struct device *dev);

#endif /* __CLK_EXYNOS_ARM64_H */
diff --git a/drivers/clk/samsung/clk-exynos5433.c b/drivers/clk/samsung/clk-exynos5433.c
index eb72bf2aaee8..ed43233649ae 100644
--- a/drivers/clk/samsung/clk-exynos5433.c
+++ b/drivers/clk/samsung/clk-exynos5433.c
@@ -10,7 +10,6 @@
#include <linux/clk-provider.h>
#include <linux/of.h>
#include <linux/of_address.h>
-#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
@@ -19,6 +18,7 @@

#include "clk.h"
#include "clk-cpu.h"
+#include "clk-exynos-arm64.h"
#include "clk-pll.h"

/*
@@ -5478,160 +5478,9 @@ static const struct samsung_cmu_info imem_cmu_info __initconst = {
.clk_name = "aclk_imem_200",
};

-struct exynos5433_cmu_data {
- struct samsung_clk_reg_dump *clk_save;
- unsigned int nr_clk_save;
- const struct samsung_clk_reg_dump *clk_suspend;
- unsigned int nr_clk_suspend;
-
- struct clk *clk;
- struct clk **pclks;
- int nr_pclks;
-
- /* must be the last entry */
- struct samsung_clk_provider ctx;
-};
-
-static int __maybe_unused exynos5433_cmu_suspend(struct device *dev)
-{
- struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
- int i;
-
- samsung_clk_save(data->ctx.reg_base, data->clk_save,
- data->nr_clk_save);
-
- for (i = 0; i < data->nr_pclks; i++)
- clk_prepare_enable(data->pclks[i]);
-
- /* for suspend some registers have to be set to certain values */
- samsung_clk_restore(data->ctx.reg_base, data->clk_suspend,
- data->nr_clk_suspend);
-
- for (i = 0; i < data->nr_pclks; i++)
- clk_disable_unprepare(data->pclks[i]);
-
- clk_disable_unprepare(data->clk);
-
- return 0;
-}
-
-static int __maybe_unused exynos5433_cmu_resume(struct device *dev)
-{
- struct exynos5433_cmu_data *data = dev_get_drvdata(dev);
- int i;
-
- clk_prepare_enable(data->clk);
-
- for (i = 0; i < data->nr_pclks; i++)
- clk_prepare_enable(data->pclks[i]);
-
- samsung_clk_restore(data->ctx.reg_base, data->clk_save,
- data->nr_clk_save);
-
- for (i = 0; i < data->nr_pclks; i++)
- clk_disable_unprepare(data->pclks[i]);
-
- return 0;
-}
-
static int __init exynos5433_cmu_probe(struct platform_device *pdev)
{
- const struct samsung_cmu_info *info;
- struct exynos5433_cmu_data *data;
- struct samsung_clk_provider *ctx;
- struct device *dev = &pdev->dev;
- void __iomem *reg_base;
- int i;
-
- info = of_device_get_match_data(dev);
-
- data = devm_kzalloc(dev,
- struct_size(data, ctx.clk_data.hws, info->nr_clk_ids),
- GFP_KERNEL);
- if (!data)
- return -ENOMEM;
- ctx = &data->ctx;
-
- reg_base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(reg_base))
- return PTR_ERR(reg_base);
-
- for (i = 0; i < info->nr_clk_ids; ++i)
- ctx->clk_data.hws[i] = ERR_PTR(-ENOENT);
-
- ctx->clk_data.num = info->nr_clk_ids;
- ctx->reg_base = reg_base;
- ctx->dev = dev;
- spin_lock_init(&ctx->lock);
-
- data->clk_save = samsung_clk_alloc_reg_dump(info->clk_regs,
- info->nr_clk_regs);
- if (!data->clk_save)
- return -ENOMEM;
- data->nr_clk_save = info->nr_clk_regs;
- data->clk_suspend = info->suspend_regs;
- data->nr_clk_suspend = info->nr_suspend_regs;
- data->nr_pclks = of_clk_get_parent_count(dev->of_node);
-
- if (data->nr_pclks > 0) {
- data->pclks = devm_kcalloc(dev, sizeof(struct clk *),
- data->nr_pclks, GFP_KERNEL);
- if (!data->pclks) {
- kfree(data->clk_save);
- return -ENOMEM;
- }
- for (i = 0; i < data->nr_pclks; i++) {
- struct clk *clk = of_clk_get(dev->of_node, i);
-
- if (IS_ERR(clk)) {
- kfree(data->clk_save);
- while (--i >= 0)
- clk_put(data->pclks[i]);
- return PTR_ERR(clk);
- }
- data->pclks[i] = clk;
- }
- }
-
- if (info->clk_name)
- data->clk = clk_get(dev, info->clk_name);
- clk_prepare_enable(data->clk);
-
- platform_set_drvdata(pdev, data);
-
- /*
- * Enable runtime PM here to allow the clock core using runtime PM
- * for the registered clocks. Additionally, we increase the runtime
- * PM usage count before registering the clocks, to prevent the
- * clock core from runtime suspending the device.
- */
- pm_runtime_get_noresume(dev);
- pm_runtime_set_active(dev);
- pm_runtime_enable(dev);
-
- if (info->pll_clks)
- samsung_clk_register_pll(ctx, info->pll_clks,
- info->nr_pll_clks);
- if (info->mux_clks)
- samsung_clk_register_mux(ctx, info->mux_clks,
- info->nr_mux_clks);
- if (info->div_clks)
- samsung_clk_register_div(ctx, info->div_clks,
- info->nr_div_clks);
- if (info->gate_clks)
- samsung_clk_register_gate(ctx, info->gate_clks,
- info->nr_gate_clks);
- if (info->fixed_clks)
- samsung_clk_register_fixed_rate(ctx, info->fixed_clks,
- info->nr_fixed_clks);
- if (info->fixed_factor_clks)
- samsung_clk_register_fixed_factor(ctx, info->fixed_factor_clks,
- info->nr_fixed_factor_clks);
-
- samsung_clk_of_add_provider(dev->of_node, ctx);
- pm_runtime_put_sync(dev);
-
- return 0;
+ return exynos_arm64_register_cmu_pm(pdev, false);
}

static const struct of_device_id exynos5433_cmu_of_match[] = {
@@ -5679,7 +5528,7 @@ static const struct of_device_id exynos5433_cmu_of_match[] = {
};

static const struct dev_pm_ops exynos5433_cmu_pm_ops = {
- SET_RUNTIME_PM_OPS(exynos5433_cmu_suspend, exynos5433_cmu_resume,
+ SET_RUNTIME_PM_OPS(exynos_arm64_cmu_suspend, exynos_arm64_cmu_resume,
NULL)
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
--
2.39.2