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Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/samsung/clk-exynos5-subcmu.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk-exynos5-subcmu.c b/drivers/clk/samsung/clk-exynos5-subcmu.c new file mode 100644 index 000000000..8ae44b5db --- /dev/null +++ b/drivers/clk/samsung/clk-exynos5-subcmu.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (c) 2018 Samsung Electronics Co., Ltd. +// Author: Marek Szyprowski <m.szyprowski@samsung.com> +// Common Clock Framework support for Exynos5 power-domain dependent clocks + +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/pm_domain.h> +#include <linux/pm_runtime.h> + +#include "clk.h" +#include "clk-exynos5-subcmu.h" + +static struct samsung_clk_provider *ctx; +static const struct exynos5_subcmu_info *cmu; +static int nr_cmus; + +static void exynos5_subcmu_clk_save(void __iomem *base, + struct exynos5_subcmu_reg_dump *rd, + unsigned int num_regs) +{ + for (; num_regs > 0; --num_regs, ++rd) { + rd->save = readl(base + rd->offset); + writel((rd->save & ~rd->mask) | rd->value, base + rd->offset); + rd->save &= rd->mask; + } +}; + +static void exynos5_subcmu_clk_restore(void __iomem *base, + struct exynos5_subcmu_reg_dump *rd, + unsigned int num_regs) +{ + for (; num_regs > 0; --num_regs, ++rd) + writel((readl(base + rd->offset) & ~rd->mask) | rd->save, + base + rd->offset); +} + +static void exynos5_subcmu_defer_gate(struct samsung_clk_provider *ctx, + const struct samsung_gate_clock *list, int nr_clk) +{ + while (nr_clk--) + samsung_clk_add_lookup(ctx, ERR_PTR(-EPROBE_DEFER), list++->id); +} + +/* + * Pass the needed clock provider context and register sub-CMU clocks + * + * NOTE: This function has to be called from the main, OF_CLK_DECLARE- + * initialized clock provider driver. This happens very early during boot + * process. Then this driver, during core_initcall registers two platform + * drivers: one which binds to the same device-tree node as OF_CLK_DECLARE + * driver and second, for handling its per-domain child-devices. Those + * platform drivers are bound to their devices a bit later in arch_initcall, + * when OF-core populates all device-tree nodes. + */ +void exynos5_subcmus_init(struct samsung_clk_provider *_ctx, int _nr_cmus, + const struct exynos5_subcmu_info *_cmu) +{ + ctx = _ctx; + cmu = _cmu; + nr_cmus = _nr_cmus; + + for (; _nr_cmus--; _cmu++) { + exynos5_subcmu_defer_gate(ctx, _cmu->gate_clks, + _cmu->nr_gate_clks); + exynos5_subcmu_clk_save(ctx->reg_base, _cmu->suspend_regs, + _cmu->nr_suspend_regs); + } +} + +static int __maybe_unused exynos5_subcmu_suspend(struct device *dev) +{ + struct exynos5_subcmu_info *info = dev_get_drvdata(dev); + unsigned long flags; + + spin_lock_irqsave(&ctx->lock, flags); + exynos5_subcmu_clk_save(ctx->reg_base, info->suspend_regs, + info->nr_suspend_regs); + spin_unlock_irqrestore(&ctx->lock, flags); + + return 0; +} + +static int __maybe_unused exynos5_subcmu_resume(struct device *dev) +{ + struct exynos5_subcmu_info *info = dev_get_drvdata(dev); + unsigned long flags; + + spin_lock_irqsave(&ctx->lock, flags); + exynos5_subcmu_clk_restore(ctx->reg_base, info->suspend_regs, + info->nr_suspend_regs); + spin_unlock_irqrestore(&ctx->lock, flags); + + return 0; +} + +static int __init exynos5_subcmu_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct exynos5_subcmu_info *info = dev_get_drvdata(dev); + + pm_runtime_set_suspended(dev); + pm_runtime_enable(dev); + pm_runtime_get(dev); + + ctx->dev = dev; + samsung_clk_register_div(ctx, info->div_clks, info->nr_div_clks); + samsung_clk_register_gate(ctx, info->gate_clks, info->nr_gate_clks); + ctx->dev = NULL; + + pm_runtime_put_sync(dev); + + return 0; +} + +static const struct dev_pm_ops exynos5_subcmu_pm_ops = { + SET_RUNTIME_PM_OPS(exynos5_subcmu_suspend, + exynos5_subcmu_resume, NULL) + SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + +static struct platform_driver exynos5_subcmu_driver __refdata = { + .driver = { + .name = "exynos5-subcmu", + .suppress_bind_attrs = true, + .pm = &exynos5_subcmu_pm_ops, + }, + .probe = exynos5_subcmu_probe, +}; + +static int __init exynos5_clk_register_subcmu(struct device *parent, + const struct exynos5_subcmu_info *info, + struct device_node *pd_node) +{ + struct of_phandle_args genpdspec = { .np = pd_node }; + struct platform_device *pdev; + int ret; + + pdev = platform_device_alloc("exynos5-subcmu", PLATFORM_DEVID_AUTO); + if (!pdev) + return -ENOMEM; + + pdev->dev.parent = parent; + platform_set_drvdata(pdev, (void *)info); + of_genpd_add_device(&genpdspec, &pdev->dev); + ret = platform_device_add(pdev); + if (ret) + platform_device_put(pdev); + + return ret; +} + +static int __init exynos5_clk_probe(struct platform_device *pdev) +{ + struct device_node *np; + const char *name; + int i; + + for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") { + if (of_property_read_string(np, "label", &name) < 0) + continue; + for (i = 0; i < nr_cmus; i++) + if (strcmp(cmu[i].pd_name, name) == 0) + exynos5_clk_register_subcmu(&pdev->dev, + &cmu[i], np); + } + return 0; +} + +static const struct of_device_id exynos5_clk_of_match[] = { + { .compatible = "samsung,exynos5250-clock", }, + { .compatible = "samsung,exynos5420-clock", }, + { .compatible = "samsung,exynos5800-clock", }, + { }, +}; + +static struct platform_driver exynos5_clk_driver __refdata = { + .driver = { + .name = "exynos5-clock", + .of_match_table = exynos5_clk_of_match, + .suppress_bind_attrs = true, + }, + .probe = exynos5_clk_probe, +}; + +static int __init exynos5_clk_drv_init(void) +{ + platform_driver_register(&exynos5_clk_driver); + platform_driver_register(&exynos5_subcmu_driver); + return 0; +} +core_initcall(exynos5_clk_drv_init); |