Re: [PATCH v16 22/40] mmc: sdhci-tegra: Add runtime PM and OPP support

Adrian Hunter
2021-12-02T08:16:43Z

On 01/12/2021 01:23, Dmitry Osipenko wrote:
> The SDHCI on Tegra belongs to the core power domain and we're going to
> enable GENPD support for the core domain. Now SDHCI must be resumed using
> runtime PM API in order to initialize the SDHCI power state. The SDHCI
> clock rate must be changed using OPP API that will reconfigure the power
> domain performance state in accordance to the rate. Add runtime PM and OPP
> support to the SDHCI driver.
>
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>

Acked-by: Adrian Hunter <adrian.hunter@intel.com>

> ---
> drivers/mmc/host/sdhci-tegra.c | 81 +++++++++++++++++++++++++++-------
> 1 file changed, 65 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
> index a5001875876b..6435a75142a6 100644
> --- a/drivers/mmc/host/sdhci-tegra.c
> +++ b/drivers/mmc/host/sdhci-tegra.c
> @@ -15,6 +15,8 @@
> #include <linux/of.h>
> #include <linux/of_device.h>
> #include <linux/pinctrl/consumer.h>
> +#include <linux/pm_opp.h>
> +#include <linux/pm_runtime.h>
> #include <linux/regulator/consumer.h>
> #include <linux/reset.h>
> #include <linux/mmc/card.h>
> @@ -24,6 +26,8 @@
> #include <linux/gpio/consumer.h>
> #include <linux/ktime.h>
>
> +#include <soc/tegra/common.h>
> +
> #include "sdhci-pltfm.h"
> #include "cqhci.h"
>
> @@ -760,7 +764,9 @@ static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> {
> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
> + struct device *dev = mmc_dev(host->mmc);
> unsigned long host_clk;
> + int err;
>
> if (!clock)
> return sdhci_set_clock(host, clock);
> @@ -778,7 +784,12 @@ static void tegra_sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> * from clk_get_rate() is used.
> */
> host_clk = tegra_host->ddr_signaling ? clock * 2 : clock;
> - clk_set_rate(pltfm_host->clk, host_clk);
> +
> + err = dev_pm_opp_set_rate(dev, host_clk);
> + if (err)
> + dev_err(dev, "failed to set clk rate to %luHz: %d\n",
> + host_clk, err);
> +
> tegra_host->curr_clk_rate = host_clk;
> if (tegra_host->ddr_signaling)
> host->max_clk = host_clk;
> @@ -1705,7 +1716,6 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
> "failed to get clock\n");
> goto err_clk_get;
> }
> - clk_prepare_enable(clk);
> pltfm_host->clk = clk;
>
> tegra_host->rst = devm_reset_control_get_exclusive(&pdev->dev,
> @@ -1716,15 +1726,24 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
> goto err_rst_get;
> }
>
> - rc = reset_control_assert(tegra_host->rst);
> + rc = devm_tegra_core_dev_init_opp_table_common(&pdev->dev);
> if (rc)
> goto err_rst_get;
>
> + pm_runtime_enable(&pdev->dev);
> + rc = pm_runtime_resume_and_get(&pdev->dev);
> + if (rc)
> + goto err_pm_get;
> +
> + rc = reset_control_assert(tegra_host->rst);
> + if (rc)
> + goto err_rst_assert;
> +
> usleep_range(2000, 4000);
>
> rc = reset_control_deassert(tegra_host->rst);
> if (rc)
> - goto err_rst_get;
> + goto err_rst_assert;
>
> usleep_range(2000, 4000);
>
> @@ -1736,8 +1755,11 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
>
> err_add_host:
> reset_control_assert(tegra_host->rst);
> +err_rst_assert:
> + pm_runtime_put_sync_suspend(&pdev->dev);
> +err_pm_get:
> + pm_runtime_disable(&pdev->dev);
> err_rst_get:
> - clk_disable_unprepare(pltfm_host->clk);
> err_clk_get:
> clk_disable_unprepare(tegra_host->tmclk);
> err_power_req:
> @@ -1756,19 +1778,38 @@ static int sdhci_tegra_remove(struct platform_device *pdev)
>
> reset_control_assert(tegra_host->rst);
> usleep_range(2000, 4000);
> - clk_disable_unprepare(pltfm_host->clk);
> - clk_disable_unprepare(tegra_host->tmclk);
>
> + pm_runtime_put_sync_suspend(&pdev->dev);
> + pm_runtime_force_suspend(&pdev->dev);
> +
> + clk_disable_unprepare(tegra_host->tmclk);
> sdhci_pltfm_free(pdev);
>
> return 0;
> }
>
> -#ifdef CONFIG_PM_SLEEP
> -static int __maybe_unused sdhci_tegra_suspend(struct device *dev)
> +static int __maybe_unused sdhci_tegra_runtime_suspend(struct device *dev)
> {
> struct sdhci_host *host = dev_get_drvdata(dev);
> struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +
> + clk_disable_unprepare(pltfm_host->clk);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused sdhci_tegra_runtime_resume(struct device *dev)
> +{
> + struct sdhci_host *host = dev_get_drvdata(dev);
> + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +
> + return clk_prepare_enable(pltfm_host->clk);
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int sdhci_tegra_suspend(struct device *dev)
> +{
> + struct sdhci_host *host = dev_get_drvdata(dev);
> int ret;
>
> if (host->mmc->caps2 & MMC_CAP2_CQE) {
> @@ -1783,17 +1824,22 @@ static int __maybe_unused sdhci_tegra_suspend(struct device *dev)
> return ret;
> }
>
> - clk_disable_unprepare(pltfm_host->clk);
> + ret = pm_runtime_force_suspend(dev);
> + if (ret) {
> + sdhci_resume_host(host);
> + cqhci_resume(host->mmc);
> + return ret;
> + }
> +
> return 0;
> }
>
> -static int __maybe_unused sdhci_tegra_resume(struct device *dev)
> +static int sdhci_tegra_resume(struct device *dev)
> {
> struct sdhci_host *host = dev_get_drvdata(dev);
> - struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> int ret;
>
> - ret = clk_prepare_enable(pltfm_host->clk);
> + ret = pm_runtime_force_resume(dev);
> if (ret)
> return ret;
>
> @@ -1812,13 +1858,16 @@ static int __maybe_unused sdhci_tegra_resume(struct device *dev)
> suspend_host:
> sdhci_suspend_host(host);
> disable_clk:
> - clk_disable_unprepare(pltfm_host->clk);
> + pm_runtime_force_suspend(dev);
> return ret;
> }
> #endif
>
> -static SIMPLE_DEV_PM_OPS(sdhci_tegra_dev_pm_ops, sdhci_tegra_suspend,
> - sdhci_tegra_resume);
> +static const struct dev_pm_ops sdhci_tegra_dev_pm_ops = {
> + SET_RUNTIME_PM_OPS(sdhci_tegra_runtime_suspend, sdhci_tegra_runtime_resume,
> + NULL)
> + SET_SYSTEM_SLEEP_PM_OPS(sdhci_tegra_suspend, sdhci_tegra_resume)
> +};
>
> static struct platform_driver sdhci_tegra_driver = {
> .driver = {
>