diff options
Diffstat (limited to 'drivers/soc')
| -rw-r--r-- | drivers/soc/rockchip/pm_domains.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/drivers/soc/rockchip/pm_domains.c b/drivers/soc/rockchip/pm_domains.c index 0868b7d406fb..b1cf7d29dafd 100644 --- a/drivers/soc/rockchip/pm_domains.c +++ b/drivers/soc/rockchip/pm_domains.c @@ -8,6 +8,7 @@ #include <linux/io.h> #include <linux/iopoll.h> #include <linux/err.h> +#include <linux/mutex.h> #include <linux/pm_clock.h> #include <linux/pm_domain.h> #include <linux/of_address.h> @@ -16,6 +17,7 @@ #include <linux/clk.h> #include <linux/regmap.h> #include <linux/mfd/syscon.h> +#include <soc/rockchip/pm_domains.h> #include <dt-bindings/power/px30-power.h> #include <dt-bindings/power/rk3036-power.h> #include <dt-bindings/power/rk3066-power.h> @@ -139,6 +141,109 @@ struct rockchip_pmu { #define DOMAIN_RK3568(name, pwr, req, wakeup) \ DOMAIN_M(name, pwr, pwr, req, req, req, wakeup) +/* + * Dynamic Memory Controller may need to coordinate with us -- see + * rockchip_pmu_block(). + * + * dmc_pmu_mutex protects registration-time races, so DMC driver doesn't try to + * block() while we're initializing the PMU. + */ +static DEFINE_MUTEX(dmc_pmu_mutex); +static struct rockchip_pmu *dmc_pmu; + +/* + * Block PMU transitions and make sure they don't interfere with ARM Trusted + * Firmware operations. There are two conflicts, noted in the comments below. + * + * Caller must unblock PMU transitions via rockchip_pmu_unblock(). + */ +int rockchip_pmu_block(void) +{ + struct rockchip_pmu *pmu; + struct generic_pm_domain *genpd; + struct rockchip_pm_domain *pd; + int i, ret; + + mutex_lock(&dmc_pmu_mutex); + + /* No PMU (yet)? Then we just block rockchip_pmu_probe(). */ + if (!dmc_pmu) + return 0; + pmu = dmc_pmu; + + /* + * mutex blocks all idle transitions: we can't touch the + * PMU_BUS_IDLE_REQ (our ".idle_offset") register while ARM Trusted + * Firmware might be using it. + */ + mutex_lock(&pmu->mutex); + + /* + * Power domain clocks: Per Rockchip, we *must* keep certain clocks + * enabled for the duration of power-domain transitions. Most + * transitions are handled by this driver, but some cases (in + * particular, DRAM DVFS / memory-controller idle) must be handled by + * firmware. Firmware can handle most clock management via a special + * "ungate" register (PMU_CRU_GATEDIS_CON0), but unfortunately, this + * doesn't handle PLLs. We can assist this transition by doing the + * clock management on behalf of firmware. + */ + for (i = 0; i < pmu->genpd_data.num_domains; i++) { + genpd = pmu->genpd_data.domains[i]; + if (genpd) { + pd = to_rockchip_pd(genpd); + ret = clk_bulk_enable(pd->num_clks, pd->clks); + if (ret < 0) { + dev_err(pmu->dev, + "failed to enable clks for domain '%s': %d\n", + genpd->name, ret); + goto err; + } + } + } + + return 0; + +err: + for (i = i - 1; i >= 0; i--) { + genpd = pmu->genpd_data.domains[i]; + if (genpd) { + pd = to_rockchip_pd(genpd); + clk_bulk_disable(pd->num_clks, pd->clks); + } + } + mutex_unlock(&pmu->mutex); + mutex_unlock(&dmc_pmu_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(rockchip_pmu_block); + +/* Unblock PMU transitions. */ +void rockchip_pmu_unblock(void) +{ + struct rockchip_pmu *pmu; + struct generic_pm_domain *genpd; + struct rockchip_pm_domain *pd; + int i; + + if (dmc_pmu) { + pmu = dmc_pmu; + for (i = 0; i < pmu->genpd_data.num_domains; i++) { + genpd = pmu->genpd_data.domains[i]; + if (genpd) { + pd = to_rockchip_pd(genpd); + clk_bulk_disable(pd->num_clks, pd->clks); + } + } + + mutex_unlock(&pmu->mutex); + } + + mutex_unlock(&dmc_pmu_mutex); +} +EXPORT_SYMBOL_GPL(rockchip_pmu_unblock); + static bool rockchip_pmu_domain_is_idle(struct rockchip_pm_domain *pd) { struct rockchip_pmu *pmu = pd->pmu; @@ -690,6 +795,12 @@ static int rockchip_pm_domain_probe(struct platform_device *pdev) error = -ENODEV; + /* + * Prevent any rockchip_pmu_block() from racing with the remainder of + * setup (clocks, register initialization). + */ + mutex_lock(&dmc_pmu_mutex); + for_each_available_child_of_node(np, node) { error = rockchip_pm_add_one_domain(pmu, node); if (error) { @@ -719,10 +830,17 @@ static int rockchip_pm_domain_probe(struct platform_device *pdev) goto err_out; } + /* We only expect one PMU. */ + if (!WARN_ON_ONCE(dmc_pmu)) + dmc_pmu = pmu; + + mutex_unlock(&dmc_pmu_mutex); + return 0; err_out: rockchip_pm_domain_cleanup(pmu); + mutex_unlock(&dmc_pmu_mutex); return error; } |