[PATCH v14 2/3] power-domain: rockchip: add power domain driver

Ulf Hansson ulf.hansson at linaro.org
Thu May 28 03:38:08 PDT 2015


On 24 April 2015 at 10:07, Caesar Wang <wxt at rock-chips.com> wrote:
> In order to meet high performance and low power requirements, a power
> management unit is designed or saving power when RK3288 in low power
> mode.
> The RK3288 PMU is dedicated for managing the power ot the whole chip.
>
> Signed-off-by: jinkun.hong <jinkun.hong at rock-chips.com>
> Signed-off-by: Caesar Wang <wxt at rock-chips.com>
> ---
>
>  arch/arm/mach-rockchip/Kconfig      |   1 +
>  arch/arm/mach-rockchip/Makefile     |   1 +
>  arch/arm/mach-rockchip/pm_domains.c | 506 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 508 insertions(+)
>  create mode 100644 arch/arm/mach-rockchip/pm_domains.c
>
> diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
> index ae4eb7c..578206b 100644
> --- a/arch/arm/mach-rockchip/Kconfig
> +++ b/arch/arm/mach-rockchip/Kconfig
> @@ -15,6 +15,7 @@ config ARCH_ROCKCHIP
>         select ROCKCHIP_TIMER
>         select ARM_GLOBAL_TIMER
>         select CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
> +       select PM_GENERIC_DOMAINS if PM
>         help
>           Support for Rockchip's Cortex-A9 Single-to-Quad-Core-SoCs
>           containing the RK2928, RK30xx and RK31xx series.
> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> index 5c3a9b2..9c902d3 100644
> --- a/arch/arm/mach-rockchip/Makefile
> +++ b/arch/arm/mach-rockchip/Makefile
> @@ -1,5 +1,6 @@
>  CFLAGS_platsmp.o := -march=armv7-a
>
>  obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip.o
> +obj-$(CONFIG_PM_GENERIC_DOMAINS) += pm_domains.o
>  obj-$(CONFIG_PM_SLEEP) += pm.o sleep.o
>  obj-$(CONFIG_SMP) += headsmp.o platsmp.o
> diff --git a/arch/arm/mach-rockchip/pm_domains.c b/arch/arm/mach-rockchip/pm_domains.c
> new file mode 100644
> index 0000000..92d2569
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/pm_domains.c
> @@ -0,0 +1,506 @@
> +/*
> + * Rockchip Generic power domain support.
> + *
> + * Copyright (c) 2014 ROCKCHIP, Co. Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/err.h>
> +#include <linux/pm_clock.h>
> +#include <linux/pm_domain.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>

clk-provider.h, why?

> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +#include <dt-bindings/power-domain/rk3288.h>

Same comment as in patch1. I don't find this header.

> +
> +struct rockchip_domain_info {
> +       int pwr_mask;
> +       int status_mask;
> +       int req_mask;
> +       int idle_mask;
> +       int ack_mask;
> +};
> +
> +struct rockchip_pmu_info {
> +       u32 pwr_offset;
> +       u32 status_offset;
> +       u32 req_offset;
> +       u32 idle_offset;
> +       u32 ack_offset;
> +
> +       u32 core_pwrcnt_offset;
> +       u32 gpu_pwrcnt_offset;
> +
> +       unsigned int core_power_transition_time;
> +       unsigned int gpu_power_transition_time;
> +
> +       int num_domains;
> +       const struct rockchip_domain_info *domain_info;
> +};
> +
> +struct rockchip_pm_domain {
> +       struct generic_pm_domain genpd;
> +       const struct rockchip_domain_info *info;
> +       struct rockchip_pmu *pmu;
> +       int num_clks;
> +       struct clk *clks[];
> +};
> +
> +struct rockchip_pmu {
> +       struct device *dev;
> +       struct regmap *regmap;
> +       const struct rockchip_pmu_info *info;
> +       struct mutex mutex; /* mutex lock for pmu */
> +       struct genpd_onecell_data genpd_data;
> +       struct generic_pm_domain *domains[];
> +};
> +
> +#define to_rockchip_pd(gpd) container_of(gpd, struct rockchip_pm_domain, genpd)
> +
> +#define DOMAIN(pwr, status, req, idle, ack)    \
> +{                                              \
> +       .pwr_mask = BIT(pwr),                   \
> +       .status_mask = BIT(status),             \
> +       .req_mask = BIT(req),                   \
> +       .idle_mask = BIT(idle),                 \
> +       .ack_mask = BIT(ack),                   \
> +}
> +
> +#define DOMAIN_RK3288(pwr, status, req)                \
> +       DOMAIN(pwr, status, req, req, (req) + 16)
> +
> +static bool rockchip_pmu_domain_is_idle(struct rockchip_pm_domain *pd)
> +{
> +       struct rockchip_pmu *pmu = pd->pmu;
> +       const struct rockchip_domain_info *pd_info = pd->info;
> +       unsigned int val;
> +
> +       regmap_read(pmu->regmap, pmu->info->idle_offset, &val);
> +       return (val & pd_info->idle_mask) == pd_info->idle_mask;
> +}
> +
> +static int rockchip_pmu_set_idle_request(struct rockchip_pm_domain *pd,
> +                                        bool idle)
> +{
> +       const struct rockchip_domain_info *pd_info = pd->info;
> +       struct rockchip_pmu *pmu = pd->pmu;
> +       unsigned int val;
> +
> +       regmap_update_bits(pmu->regmap, pmu->info->req_offset,
> +                          pd_info->req_mask, idle ? -1U : 0);
> +
> +       dsb();
> +
> +       do {
> +               regmap_read(pmu->regmap, pmu->info->ack_offset, &val);
> +       } while ((val & pd_info->ack_mask) != (idle ? pd_info->ack_mask : 0));
> +
> +       while (rockchip_pmu_domain_is_idle(pd) != idle)
> +               cpu_relax();
> +
> +       return 0;
> +}
> +
> +static bool rockchip_pmu_domain_is_on(struct rockchip_pm_domain *pd)
> +{
> +       struct rockchip_pmu *pmu = pd->pmu;
> +       unsigned int val;
> +
> +       regmap_read(pmu->regmap, pmu->info->status_offset, &val);
> +
> +       /* 1'b0: power on, 1'b1: power off */
> +       return !(val & pd->info->status_mask);
> +}
> +
> +static void rockchip_do_pmu_set_power_domain(struct rockchip_pm_domain *pd,
> +                                            bool on)
> +{
> +       struct rockchip_pmu *pmu = pd->pmu;
> +
> +       regmap_update_bits(pmu->regmap, pmu->info->pwr_offset,
> +                          pd->info->pwr_mask, on ? 0 : -1U);
> +
> +       dsb();
> +
> +       while (rockchip_pmu_domain_is_on(pd) != on)
> +               cpu_relax();
> +}
> +
> +static int rockchip_pd_power(struct rockchip_pm_domain *pd, bool power_on)
> +{
> +       int i;
> +
> +       mutex_lock(&pd->pmu->mutex);

I don't quite understand why you need a lock, what are you protecting and why?

> +
> +       if (rockchip_pmu_domain_is_on(pd) != power_on) {
> +               for (i = 0; i < pd->num_clks; i++)
> +                       clk_enable(pd->clks[i]);
> +
> +               if (!power_on) {
> +                       /* FIXME: add code to save AXI_QOS */
> +
> +                       /* if powering down, idle request to NIU first */
> +                       rockchip_pmu_set_idle_request(pd, true);
> +               }
> +
> +               rockchip_do_pmu_set_power_domain(pd, power_on);
> +
> +               if (power_on) {
> +                       /* if powering up, leave idle mode */
> +                       rockchip_pmu_set_idle_request(pd, false);
> +
> +                       /* FIXME: add code to restore AXI_QOS */
> +               }
> +
> +               for (i = pd->num_clks - 1; i >= 0; i--)
> +                       clk_disable(pd->clks[i]);
> +       }
> +
> +       mutex_unlock(&pd->pmu->mutex);
> +       return 0;
> +}
> +
> +static int rockchip_pd_power_on(struct generic_pm_domain *domain)
> +{
> +       struct rockchip_pm_domain *pd = to_rockchip_pd(domain);
> +
> +       return rockchip_pd_power(pd, true);
> +}
> +
> +static int rockchip_pd_power_off(struct generic_pm_domain *domain)
> +{
> +       struct rockchip_pm_domain *pd = to_rockchip_pd(domain);
> +
> +       return rockchip_pd_power(pd, false);
> +}
> +
> +static int rockchip_pd_attach_dev(struct generic_pm_domain *genpd,
> +                                 struct device *dev)
> +{
> +       struct clk *clk;
> +       int i;
> +       int error;
> +
> +       dev_dbg(dev, "attaching to power domain '%s'\n", genpd->name);
> +
> +       error = pm_clk_create(dev);
> +       if (error) {
> +               dev_err(dev, "pm_clk_create failed %d\n", error);
> +               return error;
> +       }
> +
> +       i = 0;

> +       while ((clk = of_clk_get(dev->of_node, i++)) && !IS_ERR(clk)) {

This loop adds all available device clocks to the PM clock list. I
wonder if this could be considered as a common thing and if so, we
might want to extend the pm_clk API with this.

> +               dev_dbg(dev, "adding clock '%s' to list of PM clocks\n",
> +                       __clk_get_name(clk));
> +               error = pm_clk_add_clk(dev, clk);
> +               clk_put(clk);
> +               if (error) {
> +                       dev_err(dev, "pm_clk_add_clk failed %d\n", error);
> +                       pm_clk_destroy(dev);
> +                       return error;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +static void rockchip_pd_detach_dev(struct generic_pm_domain *genpd,
> +                                  struct device *dev)
> +{
> +       dev_dbg(dev, "detaching from power domain '%s'\n", genpd->name);
> +
> +       pm_clk_destroy(dev);
> +}
> +
> +static int rockchip_pd_start_dev(struct device *dev)
> +{
> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
> +
> +       dev_dbg(dev, "starting device in power domain '%s'\n", genpd->name);
> +
> +       return pm_clk_resume(dev);
> +}
> +
> +static int rockchip_pd_stop_dev(struct device *dev)
> +{
> +       struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
> +
> +       dev_dbg(dev, "stopping device in power domain '%s'\n", genpd->name);
> +
> +       return pm_clk_suspend(dev);
> +}
> +
> +static int rockchip_pm_add_one_domain(struct rockchip_pmu *pmu,
> +                                     struct device_node *node)
> +{
> +       const struct rockchip_domain_info *pd_info;
> +       struct rockchip_pm_domain *pd;
> +       struct clk *clk;
> +       int clk_cnt;
> +       int i;
> +       u32 id;
> +       int error;
> +
> +       error = of_property_read_u32(node, "reg", &id);
> +       if (error) {
> +               dev_err(pmu->dev,
> +                       "%s: failed to retrieve domain id (reg): %d\n",
> +                       node->name, error);
> +               return -EINVAL;
> +       }
> +
> +       if (id >= pmu->info->num_domains) {
> +               dev_err(pmu->dev, "%s: invalid domain id %d\n",
> +                       node->name, id);
> +               return -EINVAL;
> +       }
> +
> +       pd_info = &pmu->info->domain_info[id];
> +       if (!pd_info) {
> +               dev_err(pmu->dev, "%s: undefined domain id %d\n",
> +                       node->name, id);
> +               return -EINVAL;
> +       }
> +
> +       clk_cnt = of_count_phandle_with_args(node, "clocks", "#clock-cells");
> +       pd = devm_kzalloc(pmu->dev,
> +                         sizeof(*pd) + clk_cnt * sizeof(pd->clks[0]),
> +                         GFP_KERNEL);
> +       if (!pd)
> +               return -ENOMEM;
> +
> +       pd->info = pd_info;
> +       pd->pmu = pmu;
> +
> +       for (i = 0; i < clk_cnt; i++) {

This loop is similar to the one when creates the PM clock list in the
rockchip_pd_attach_dev().

What's the reason you don't want to use pm clk for these clocks?

> +               clk = of_clk_get(node, i);
> +               if (IS_ERR(clk)) {
> +                       error = PTR_ERR(clk);
> +                       dev_err(pmu->dev,
> +                               "%s: failed to get clk %s (index %d): %d\n",
> +                               node->name, __clk_get_name(clk), i, error);
> +                       goto err_out;
> +               }
> +
> +               error = clk_prepare(clk);
> +               if (error) {
> +                       dev_err(pmu->dev,
> +                               "%s: failed to prepare clk %s (index %d): %d\n",
> +                               node->name, __clk_get_name(clk), i, error);
> +                       clk_put(clk);
> +                       goto err_out;
> +               }
> +
> +               pd->clks[pd->num_clks++] = clk;
> +
> +               dev_dbg(pmu->dev, "added clock '%s' to domain '%s'\n",
> +                       __clk_get_name(clk), node->name);
> +       }
> +
> +       error = rockchip_pd_power(pd, true);
> +       if (error) {
> +               dev_err(pmu->dev,
> +                       "failed to power on domain '%s': %d\n",
> +                       node->name, error);
> +               goto err_out;
> +       }
> +
> +       pd->genpd.name = node->name;
> +       pd->genpd.power_off = rockchip_pd_power_off;
> +       pd->genpd.power_on = rockchip_pd_power_on;
> +       pd->genpd.attach_dev = rockchip_pd_attach_dev;
> +       pd->genpd.detach_dev = rockchip_pd_detach_dev;
> +       pd->genpd.dev_ops.start = rockchip_pd_start_dev;
> +       pd->genpd.dev_ops.stop = rockchip_pd_stop_dev;

Instead of assigning the ->stop|start() callbacks, which do
pm_clk_suspend|resume(), just set the genpd->flags to
GENPD_FLAG_PM_CLK, and genpd will fix this for you.

> +       pm_genpd_init(&pd->genpd, NULL, false);
> +
> +       pmu->genpd_data.domains[id] = &pd->genpd;
> +       return 0;
> +
> +err_out:
> +       while (--i >= 0) {
> +               clk_unprepare(pd->clks[i]);
> +               clk_put(pd->clks[i]);
> +       }
> +       return error;
> +}
> +
> +static void rockchip_pm_remove_one_domain(struct rockchip_pm_domain *pd)
> +{
> +       int i;
> +
> +       for (i = 0; i < pd->num_clks; i++) {
> +               clk_unprepare(pd->clks[i]);

If you converted these clocks to be dealt with via the PM clk API,
pm_clk_destoy() would have replaced this loop.

> +               clk_put(pd->clks[i]);
> +       }
> +
> +       /* devm will free our memory */
> +}
> +
> +static void rockchip_pm_domain_cleanup(struct rockchip_pmu *pmu)
> +{
> +       struct generic_pm_domain *genpd;
> +       struct rockchip_pm_domain *pd;
> +       int i;
> +
> +       for (i = 0; i < pmu->genpd_data.num_domains; i++) {
> +               genpd = pmu->genpd_data.domains[i];
> +               if (genpd) {
> +                       pd = to_rockchip_pd(genpd);
> +                       rockchip_pm_remove_one_domain(pd);
> +               }
> +       }
> +
> +       /* devm will free our memory */
> +}
> +
> +static void rockchip_configure_pd_cnt(struct rockchip_pmu *pmu,
> +                                     u32 domain_reg_offset,
> +                                     unsigned int count)
> +{
> +       /* First configure domain power down transition count ... */
> +       regmap_write(pmu->regmap, domain_reg_offset, count);
> +       /* ... and then power up count. */
> +       regmap_write(pmu->regmap, domain_reg_offset + 4, count);
> +}
> +
> +static int rockchip_pm_domain_probe(struct platform_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct device_node *np = dev->of_node;
> +       struct device_node *node;
> +       struct rockchip_pmu *pmu;
> +       const struct of_device_id *match;
> +       const struct rockchip_pmu_info *pmu_info;
> +       int error;
> +
> +       if (!np) {
> +               dev_err(dev, "device tree node not found\n");
> +               return -ENXIO;/

Nitpick:
It's more common to return -ENODEV here, you might want to change.

> +       }
> +
> +       match = of_match_device(dev->driver->of_match_table, dev);
> +       if (!match || !match->data) {
> +               dev_err(dev, "missing pmu data\n");
> +               return -EINVAL;
> +       }
> +
> +       pmu_info = match->data;
> +
> +       pmu = devm_kzalloc(dev,
> +                          sizeof(*pmu) +
> +                               pmu_info->num_domains * sizeof(pmu->domains[0]),
> +                          GFP_KERNEL);
> +       if (!pmu)
> +               return -ENOMEM;
> +
> +       pmu->dev = &pdev->dev;
> +       mutex_init(&pmu->mutex);
> +
> +       pmu->info = pmu_info;
> +
> +       pmu->genpd_data.domains = pmu->domains;
> +       pmu->genpd_data.num_domains = pmu_info->num_domains;
> +
> +       node = of_parse_phandle(np, "rockchip,pmu", 0);
> +       pmu->regmap = syscon_node_to_regmap(node);
> +       of_node_put(node);
> +       if (IS_ERR(pmu->regmap)) {
> +               error = PTR_ERR(pmu->regmap);
> +               dev_err(dev, "failed to get PMU regmap: %d\n", error);
> +               return error;
> +       }
> +
> +       /*
> +        * Configure power up and down transition delays for core
> +        * and GPU domains.
> +        */
> +       rockchip_configure_pd_cnt(pmu, pmu_info->core_pwrcnt_offset,
> +                                 pmu_info->core_power_transition_time);
> +       rockchip_configure_pd_cnt(pmu, pmu_info->gpu_pwrcnt_offset,
> +                                 pmu_info->gpu_power_transition_time);
> +
> +       error = -ENXIO;
> +
> +       for_each_available_child_of_node(np, node) {
> +               error = rockchip_pm_add_one_domain(pmu, node);
> +               if (error) {
> +                       dev_err(dev, "failed to handle node %s: %d\n",
> +                               node->name, error);
> +                       goto err_out;
> +               }
> +       }
> +
> +       if (error) {
> +               dev_dbg(dev, "no power domains defined\n");
> +               goto err_out;
> +       }
> +
> +       of_genpd_add_provider_onecell(np, &pmu->genpd_data);
> +
> +       return 0;
> +
> +err_out:
> +       rockchip_pm_domain_cleanup(pmu);
> +       return error;
> +}
> +
> +static const struct rockchip_domain_info rk3288_pm_domains[] = {
> +       [RK3288_PD_GPU]         = DOMAIN_RK3288(9, 9, 2),
> +       [RK3288_PD_VIO]         = DOMAIN_RK3288(7, 7, 4),
> +       [RK3288_PD_VIDEO]       = DOMAIN_RK3288(8, 8, 3),
> +       [RK3288_PD_HEVC]        = DOMAIN_RK3288(14, 10, 9),
> +};
> +
> +static const struct rockchip_pmu_info rk3288_pmu = {
> +       .pwr_offset = 0x08,
> +       .status_offset = 0x0c,
> +       .req_offset = 0x10,
> +       .idle_offset = 0x14,
> +       .ack_offset = 0x14,
> +
> +       .core_pwrcnt_offset = 0x34,
> +       .gpu_pwrcnt_offset = 0x3c,
> +
> +       .core_power_transition_time = 24, /* 1us */
> +       .gpu_power_transition_time = 24, /* 1us */
> +
> +       .num_domains = ARRAY_SIZE(rk3288_pm_domains),
> +       .domain_info = rk3288_pm_domains,
> +};
> +
> +static const struct of_device_id rockchip_pm_domain_dt_match[] = {
> +       {
> +               .compatible = "rockchip,rk3288-power-controller",
> +               .data = (void *)&rk3288_pmu,
> +       },
> +       { /* sentinel */ },
> +};
> +
> +static struct platform_driver rockchip_pm_domain_driver = {
> +       .probe = rockchip_pm_domain_probe,
> +       .driver = {
> +               .name   = "rockchip-pm-domain",
> +               .of_match_table = rockchip_pm_domain_dt_match,
> +               /*
> +                * We can't forcibly eject devices form power domain,
> +                * so we can't really remove power domains once they
> +                * were added.
> +                */
> +               .suppress_bind_attrs = true,
> +       },
> +};
> +
> +static int __init rockchip_pm_domain_drv_register(void)
> +{
> +       return platform_driver_register(&rockchip_pm_domain_driver);
> +}
> +postcore_initcall(rockchip_pm_domain_drv_register);
> --
> 1.9.1
>

Kind regards
Uffe



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