[PATCH v2 6/9] soc: imx: add i.MX8MP HSIO blk-ctrl

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon Feb 21 03:29:52 PST 2022


Hi Lucas,

Thank you for the patch.

On Mon, Feb 07, 2022 at 08:25:44PM +0100, Lucas Stach wrote:
> The i.MX8MP added some blk-ctrl peripherals that don't follow the regular
> structure of the blk-ctrls in the previous SoCs. Add a new file for those
> with currently only the HSIO blk-ctrl being supported. Others will be added
> later on.
> 
> Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
> ---
>  drivers/soc/imx/Makefile          |   1 +
>  drivers/soc/imx/imx8mp-blk-ctrl.c | 444 ++++++++++++++++++++++++++++++
>  2 files changed, 445 insertions(+)
>  create mode 100644 drivers/soc/imx/imx8mp-blk-ctrl.c
> 
> diff --git a/drivers/soc/imx/Makefile b/drivers/soc/imx/Makefile
> index 8a707077914c..63cd29f6d4d2 100644
> --- a/drivers/soc/imx/Makefile
> +++ b/drivers/soc/imx/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_HAVE_IMX_GPC) += gpc.o
>  obj-$(CONFIG_IMX_GPCV2_PM_DOMAINS) += gpcv2.o
>  obj-$(CONFIG_SOC_IMX8M) += soc-imx8m.o
>  obj-$(CONFIG_SOC_IMX8M) += imx8m-blk-ctrl.o
> +obj-$(CONFIG_SOC_IMX8M) += imx8mp-blk-ctrl.o
> diff --git a/drivers/soc/imx/imx8mp-blk-ctrl.c b/drivers/soc/imx/imx8mp-blk-ctrl.c
> new file mode 100644
> index 000000000000..7f4e1a151d2b
> --- /dev/null
> +++ b/drivers/soc/imx/imx8mp-blk-ctrl.c
> @@ -0,0 +1,444 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +
> +/*
> + * Copyright 2022 Pengutronix, Lucas Stach <kernel at pengutronix.de>
> + */
> +
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_domain.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regmap.h>
> +#include <linux/clk.h>

clk.h should go first in alphabetical order.

> +
> +#include <dt-bindings/power/imx8mp-power.h>
> +
> +#define GPR_REG0		0x0
> +#define  PCIE_CLOCK_MODULE_EN	BIT(0)
> +#define  USB_CLOCK_MODULE_EN	BIT(1)
> +
> +struct imx8mp_hsio_blk_ctrl_domain;
> +
> +struct imx8mp_hsio_blk_ctrl {
> +	struct device *dev;
> +	struct notifier_block power_nb;
> +	struct device *bus_power_dev;
> +	struct regmap *regmap;
> +	struct imx8mp_hsio_blk_ctrl_domain *domains;
> +	struct genpd_onecell_data onecell_data;
> +};
> +
> +struct imx8mp_hsio_blk_ctrl_domain_data {
> +	const char *name;
> +	const char *clk_name;
> +	const char *gpc_name;
> +};
> +
> +struct imx8mp_hsio_blk_ctrl_domain {
> +	struct generic_pm_domain genpd;
> +	struct clk *clk;
> +	struct device *power_dev;
> +	struct imx8mp_hsio_blk_ctrl *bc;
> +	int id;
> +};
> +
> +static inline struct imx8mp_hsio_blk_ctrl_domain *
> +to_imx8mp_hsio_blk_ctrl_domain(struct generic_pm_domain *genpd)
> +{
> +	return container_of(genpd, struct imx8mp_hsio_blk_ctrl_domain, genpd);
> +}
> +
> +static int imx8mp_hsio_blk_ctrl_power_on(struct generic_pm_domain *genpd)
> +{
> +	struct imx8mp_hsio_blk_ctrl_domain *domain =
> +			to_imx8mp_hsio_blk_ctrl_domain(genpd);
> +	struct imx8mp_hsio_blk_ctrl *bc = domain->bc;
> +	int ret;
> +
> +	/* make sure bus domain is awake */
> +	ret = pm_runtime_get_sync(bc->bus_power_dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(bc->bus_power_dev);
> +		dev_err(bc->dev, "failed to power up bus domain\n");
> +		return ret;
> +	}

	ret = pm_runtime_resume_and_get(bc->bus_power_dev);
	if (ret < 0) {
		dev_err(bc->dev, "failed to power up bus domain\n");
		return ret;
	}

Same below and in two locations in imx8mp_hsio_blk_ctrl_suspend().

> +
> +	/* enable upstream and blk-ctrl clocks */
> +	ret = clk_prepare_enable(domain->clk);
> +	if (ret) {
> +		dev_err(bc->dev, "failed to enable clocks\n");
> +		goto bus_put;
> +	}
> +
> +	switch (domain->id) {
> +	case IMX8MP_HSIOBLK_PD_USB:
> +		regmap_set_bits(bc->regmap, GPR_REG0, USB_CLOCK_MODULE_EN);
> +		break;
> +	case IMX8MP_HSIOBLK_PD_PCIE:
> +		regmap_set_bits(bc->regmap, GPR_REG0, PCIE_CLOCK_MODULE_EN);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	/* power up upstream GPC domain */
> +	ret = pm_runtime_get_sync(domain->power_dev);
> +	if (ret < 0) {

This would be missing pm_runtime_put_noidle() if you didn't switch to
pm_runtime_resume_and_get().

> +		dev_err(bc->dev, "failed to power up peripheral domain\n");
> +		goto clk_disable;
> +	}
> +
> +	return 0;
> +
> +clk_disable:
> +	clk_disable_unprepare(domain->clk);
> +bus_put:
> +	pm_runtime_put(bc->bus_power_dev);
> +
> +	return ret;
> +}
> +
> +static int imx8mp_hsio_blk_ctrl_power_off(struct generic_pm_domain *genpd)
> +{
> +	struct imx8mp_hsio_blk_ctrl_domain *domain =
> +			to_imx8mp_hsio_blk_ctrl_domain(genpd);
> +	struct imx8mp_hsio_blk_ctrl *bc = domain->bc;
> +
> +	/* disable clocks */
> +	switch (domain->id) {
> +	case IMX8MP_HSIOBLK_PD_USB:
> +		regmap_clear_bits(bc->regmap, GPR_REG0, USB_CLOCK_MODULE_EN);
> +		break;
> +	case IMX8MP_HSIOBLK_PD_PCIE:
> +		regmap_clear_bits(bc->regmap, GPR_REG0, PCIE_CLOCK_MODULE_EN);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	clk_disable_unprepare(domain->clk);
> +
> +	/* power down upstream GPC domain */
> +	pm_runtime_put(domain->power_dev);
> +
> +	/* allow bus domain to suspend */
> +	pm_runtime_put(bc->bus_power_dev);
> +
> +	return 0;
> +}
> +
> +static struct generic_pm_domain *
> +imx8m_blk_ctrl_xlate(struct of_phandle_args *args, void *data)
> +{
> +	struct genpd_onecell_data *onecell_data = data;
> +	unsigned int index = args->args[0];
> +
> +	if (args->args_count != 1 ||
> +	    index >= onecell_data->num_domains)
> +		return ERR_PTR(-EINVAL);
> +
> +	return onecell_data->domains[index];
> +}
> +
> +static struct lock_class_key blk_ctrl_genpd_lock_class;
> +
> +static const struct imx8mp_hsio_blk_ctrl_domain_data imx8mp_hsio_domain_data[] = {
> +	[IMX8MP_HSIOBLK_PD_USB] = {
> +		.name = "hsioblk-usb",
> +		.clk_name = "usb",
> +		.gpc_name = "usb",
> +	},
> +	[IMX8MP_HSIOBLK_PD_USB_PHY1] = {
> +		.name = "hsioblk-ubs-phy1",
> +		.gpc_name = "usb-phy1",
> +	},
> +	[IMX8MP_HSIOBLK_PD_USB_PHY2] = {
> +		.name = "hsioblk-ubs-phy2",
> +		.gpc_name = "usb-phy2",
> +	},
> +	[IMX8MP_HSIOBLK_PD_PCIE] = {
> +		.name = "hsioblk-pcie",
> +		.clk_name = "pcie",
> +		.gpc_name = "pcie",
> +	},
> +	[IMX8MP_HSIOBLK_PD_PCIE_PHY] = {
> +		.name = "hsioblk-pcie-phy",
> +		.gpc_name = "pcie-phy",
> +	},
> +};
> +
> +static int imx8mp_hsio_power_notifier(struct notifier_block *nb,
> +				      unsigned long action, void *data)
> +{
> +	struct imx8mp_hsio_blk_ctrl *bc = container_of(nb, struct imx8mp_hsio_blk_ctrl,
> +						 power_nb);
> +	struct clk *usb_clk = bc->domains[IMX8MP_HSIOBLK_PD_USB].clk;
> +	int ret;
> +
> +	switch (action) {
> +	case GENPD_NOTIFY_ON:
> +		/*
> +		 * enable USB clock for a moment for the power-on ADB handshake
> +		 * to proceed
> +		 */
> +		ret = clk_prepare_enable(usb_clk);
> +		if (ret)
> +			return NOTIFY_BAD;
> +		regmap_set_bits(bc->regmap, GPR_REG0, USB_CLOCK_MODULE_EN);
> +
> +		udelay(5);
> +
> +		regmap_clear_bits(bc->regmap, GPR_REG0, USB_CLOCK_MODULE_EN);
> +		clk_disable_unprepare(usb_clk);
> +		break;
> +	case GENPD_NOTIFY_PRE_OFF:
> +		/* enable USB clock for the power-down ADB handshake to work */
> +		ret = clk_prepare_enable(usb_clk);
> +		if (ret)
> +			return NOTIFY_BAD;
> +
> +		regmap_set_bits(bc->regmap, GPR_REG0, USB_CLOCK_MODULE_EN);
> +		break;
> +	case GENPD_NOTIFY_OFF:

No need to clear USB_CLOCK_MODULE_EN here ?

> +		clk_disable_unprepare(usb_clk);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return NOTIFY_OK;
> +}
> +
> +static int imx8mp_hsio_blk_ctrl_probe(struct platform_device *pdev)
> +{
> +	int num_domains = ARRAY_SIZE(imx8mp_hsio_domain_data);
> +	struct device *dev = &pdev->dev;
> +	struct imx8mp_hsio_blk_ctrl *bc;
> +	void __iomem *base;
> +	int i, ret;
> +
> +	struct regmap_config regmap_config = {

This can be static const

> +		.reg_bits	= 32,
> +		.val_bits	= 32,
> +		.reg_stride	= 4,
> +		.max_register	= 0x24,
> +	};
> +
> +	bc = devm_kzalloc(dev, sizeof(*bc), GFP_KERNEL);
> +	if (!bc)
> +		return -ENOMEM;
> +
> +	bc->dev = dev;
> +
> +	base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	bc->regmap = devm_regmap_init_mmio(dev, base, &regmap_config);
> +	if (IS_ERR(bc->regmap))
> +		return dev_err_probe(dev, PTR_ERR(bc->regmap),
> +				     "failed to init regmap\n");
> +
> +	bc->domains = devm_kcalloc(dev, num_domains,
> +				   sizeof(struct imx8mp_hsio_blk_ctrl_domain),

sizeof(*bc->domains) ? Up to you.

> +				   GFP_KERNEL);
> +	if (!bc->domains)
> +		return -ENOMEM;
> +
> +	bc->onecell_data.num_domains = num_domains;
> +	bc->onecell_data.xlate = imx8m_blk_ctrl_xlate;
> +	bc->onecell_data.domains =
> +		devm_kcalloc(dev, num_domains,
> +			     sizeof(struct generic_pm_domain *), GFP_KERNEL);
> +	if (!bc->onecell_data.domains)
> +		return -ENOMEM;
> +
> +	bc->bus_power_dev = genpd_dev_pm_attach_by_name(dev, "bus");
> +	if (IS_ERR(bc->bus_power_dev))
> +		return dev_err_probe(dev, PTR_ERR(bc->bus_power_dev),
> +				     "failed to attach power domain\n");

s/attach power domain/attach bus power domain/

> +
> +	for (i = 0; i < num_domains; i++) {
> +		const struct imx8mp_hsio_blk_ctrl_domain_data *data =
> +				&imx8mp_hsio_domain_data[i];
> +		struct imx8mp_hsio_blk_ctrl_domain *domain = &bc->domains[i];
> +
> +		if (data->clk_name) {
> +			domain->clk = devm_clk_get(dev, data->clk_name);
> +			if (IS_ERR(domain->clk)) {
> +				ret = PTR_ERR(domain->clk);
> +				dev_err_probe(dev, ret, "failed to get clock\n");

"failed to get clock %s\n", data->clk_name

could help debugging issues. Same for the gpc_name below.

With those small issues fixed,

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> +				goto cleanup_pds;
> +			}
> +		}
> +
> +		domain->power_dev =
> +			dev_pm_domain_attach_by_name(dev, data->gpc_name);
> +		if (IS_ERR(domain->power_dev)) {
> +			dev_err_probe(dev, PTR_ERR(domain->power_dev),
> +				      "failed to attach power domain\n");
> +			ret = PTR_ERR(domain->power_dev);
> +			goto cleanup_pds;
> +		}
> +
> +		domain->genpd.name = data->name;
> +		domain->genpd.power_on = imx8mp_hsio_blk_ctrl_power_on;
> +		domain->genpd.power_off = imx8mp_hsio_blk_ctrl_power_off;
> +		domain->bc = bc;
> +		domain->id = i;
> +
> +		ret = pm_genpd_init(&domain->genpd, NULL, true);
> +		if (ret) {
> +			dev_err_probe(dev, ret, "failed to init power domain\n");
> +			dev_pm_domain_detach(domain->power_dev, true);
> +			goto cleanup_pds;
> +		}
> +
> +		/*
> +		 * We use runtime PM to trigger power on/off of the upstream GPC
> +		 * domain, as a strict hierarchical parent/child power domain
> +		 * setup doesn't allow us to meet the sequencing requirements.
> +		 * This means we have nested locking of genpd locks, without the
> +		 * nesting being visible at the genpd level, so we need a
> +		 * separate lock class to make lockdep aware of the fact that
> +		 * this are separate domain locks that can be nested without a
> +		 * self-deadlock.
> +		 */
> +		lockdep_set_class(&domain->genpd.mlock,
> +				  &blk_ctrl_genpd_lock_class);
> +
> +		bc->onecell_data.domains[i] = &domain->genpd;
> +	}
> +
> +	ret = of_genpd_add_provider_onecell(dev->of_node, &bc->onecell_data);
> +	if (ret) {
> +		dev_err_probe(dev, ret, "failed to add power domain provider\n");
> +		goto cleanup_pds;
> +	}
> +
> +	bc->power_nb.notifier_call = imx8mp_hsio_power_notifier;
> +	ret = dev_pm_genpd_add_notifier(bc->bus_power_dev, &bc->power_nb);
> +	if (ret) {
> +		dev_err_probe(dev, ret, "failed to add power notifier\n");
> +		goto cleanup_provider;
> +	}
> +
> +	dev_set_drvdata(dev, bc);
> +
> +	return 0;
> +
> +cleanup_provider:
> +	of_genpd_del_provider(dev->of_node);
> +cleanup_pds:
> +	for (i--; i >= 0; i--) {
> +		pm_genpd_remove(&bc->domains[i].genpd);
> +		dev_pm_domain_detach(bc->domains[i].power_dev, true);
> +	}
> +
> +	dev_pm_domain_detach(bc->bus_power_dev, true);
> +
> +	return ret;
> +}
> +
> +static int imx8mp_hsio_blk_ctrl_remove(struct platform_device *pdev)
> +{
> +	struct imx8mp_hsio_blk_ctrl *bc = dev_get_drvdata(&pdev->dev);
> +	int i;
> +
> +	of_genpd_del_provider(pdev->dev.of_node);
> +
> +	for (i = 0; bc->onecell_data.num_domains; i++) {
> +		struct imx8mp_hsio_blk_ctrl_domain *domain = &bc->domains[i];
> +
> +		pm_genpd_remove(&domain->genpd);
> +		dev_pm_domain_detach(domain->power_dev, true);
> +	}
> +
> +	dev_pm_genpd_remove_notifier(bc->bus_power_dev);
> +
> +	dev_pm_domain_detach(bc->bus_power_dev, true);
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int imx8mp_hsio_blk_ctrl_suspend(struct device *dev)
> +{
> +	struct imx8mp_hsio_blk_ctrl *bc = dev_get_drvdata(dev);
> +	int ret, i;
> +
> +	/*
> +	 * This may look strange, but is done so the generic PM_SLEEP code
> +	 * can power down our domains and more importantly power them up again
> +	 * after resume, without tripping over our usage of runtime PM to
> +	 * control the upstream GPC domains. Things happen in the right order
> +	 * in the system suspend/resume paths due to the device parent/child
> +	 * hierarchy.
> +	 */
> +	ret = pm_runtime_get_sync(bc->bus_power_dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(bc->bus_power_dev);
> +		return ret;
> +	}
> +
> +	for (i = 0; i < bc->onecell_data.num_domains; i++) {
> +		struct imx8mp_hsio_blk_ctrl_domain *domain = &bc->domains[i];
> +
> +		ret = pm_runtime_get_sync(domain->power_dev);
> +		if (ret < 0) {
> +			pm_runtime_put_noidle(domain->power_dev);
> +			goto out_fail;
> +		}
> +	}
> +
> +	return 0;
> +
> +out_fail:
> +	for (i--; i >= 0; i--)
> +		pm_runtime_put(bc->domains[i].power_dev);
> +
> +	pm_runtime_put(bc->bus_power_dev);
> +
> +	return ret;
> +}
> +
> +static int imx8mp_hsio_blk_ctrl_resume(struct device *dev)
> +{
> +	struct imx8mp_hsio_blk_ctrl *bc = dev_get_drvdata(dev);
> +	int i;
> +
> +	for (i = 0; i < bc->onecell_data.num_domains; i++)
> +		pm_runtime_put(bc->domains[i].power_dev);
> +
> +	pm_runtime_put(bc->bus_power_dev);
> +
> +	return 0;
> +}
> +#endif
> +
> +static const struct dev_pm_ops imx8mp_hsio_blk_ctrl_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(imx8mp_hsio_blk_ctrl_suspend,
> +				imx8mp_hsio_blk_ctrl_resume)
> +};
> +
> +static const struct of_device_id imx8mp_hsio_blk_ctrl_of_match[] = {
> +	{
> +		.compatible = "fsl,imx8mp-hsio-blk-ctrl",
> +	}, {
> +		/* Sentinel */
> +	}
> +};
> +MODULE_DEVICE_TABLE(of, imx8m_blk_ctrl_of_match);
> +
> +static struct platform_driver imx8mp_hsio_blk_ctrl_driver = {
> +	.probe = imx8mp_hsio_blk_ctrl_probe,
> +	.remove = imx8mp_hsio_blk_ctrl_remove,
> +	.driver = {
> +		.name = "imx8mp-hsio-blk-ctrl",
> +		.pm = &imx8mp_hsio_blk_ctrl_pm_ops,
> +		.of_match_table = imx8mp_hsio_blk_ctrl_of_match,
> +	},
> +};
> +module_platform_driver(imx8mp_hsio_blk_ctrl_driver);

-- 
Regards,

Laurent Pinchart



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