On imx6qp power gating on the PU domain is disabled because of errata ERR009619. However power gating during suspend/resume can still be performed.
Enable this by implementing SLEEP_PM_OPS in imx_pgc_power_domain_driver. Signed-off-by: Leonard Crestez <leonard.cres...@nxp.com> --- drivers/soc/imx/gpc.c | 72 ++++++++++++++++++++++++++++++++++--------- 1 file changed, 57 insertions(+), 15 deletions(-) Changes since v1: Implement SLEEP_PM_OPS instead of calling from platform-level suspend code, as suggested by Lucas. I'm not sure if doing interesting things in the pm_ops for PM providers is recommended. Is correct ordering guaranteed in such a case? Any VPU/GPU suspend code must execute before imx_pgc_suspend or it might try to access registers in a region which is powered off. Perhaps ordering needs to be guaranteed by implementing device_attach and adding explicit device links to pgc platform_device? Link to v1: https://lkml.org/lkml/2018/7/2/370 diff --git a/drivers/soc/imx/gpc.c b/drivers/soc/imx/gpc.c index b4acdfd3cffd..96d9e882d583 100644 --- a/drivers/soc/imx/gpc.c +++ b/drivers/soc/imx/gpc.c @@ -54,19 +54,16 @@ static inline struct imx_pm_domain * to_imx_pm_domain(struct generic_pm_domain *genpd) { return container_of(genpd, struct imx_pm_domain, base); } -static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd) +static void _imx6_pm_domain_power_off(struct generic_pm_domain *genpd) { struct imx_pm_domain *pd = to_imx_pm_domain(genpd); int iso, iso2sw; u32 val; - if (pd->flags & PGC_DOMAIN_FLAG_NO_PD) - return -EBUSY; - /* Read ISO and ISO2SW power down delays */ regmap_read(pd->regmap, pd->reg_offs + GPC_PGC_PUPSCR_OFFS, &val); iso = val & 0x3f; iso2sw = (val >> 8) & 0x3f; @@ -78,32 +75,33 @@ static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd) val = BIT(pd->cntr_pdn_bit); regmap_update_bits(pd->regmap, GPC_CNTR, val, val); /* Wait ISO + ISO2SW IPG clock cycles */ udelay(DIV_ROUND_UP(iso + iso2sw, pd->ipg_rate_mhz)); +} + +static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd) +{ + struct imx_pm_domain *pd = to_imx_pm_domain(genpd); + + if (pd->flags & PGC_DOMAIN_FLAG_NO_PD) + return -EBUSY; + + _imx6_pm_domain_power_off(genpd); if (pd->supply) regulator_disable(pd->supply); return 0; } -static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd) +static void _imx6_pm_domain_power_on(struct generic_pm_domain *genpd) { struct imx_pm_domain *pd = to_imx_pm_domain(genpd); - int i, ret, sw, sw2iso; + int i, sw, sw2iso; u32 val; - if (pd->supply) { - ret = regulator_enable(pd->supply); - if (ret) { - pr_err("%s: failed to enable regulator: %d\n", - __func__, ret); - return ret; - } - } - /* Enable reset clocks for all devices in the domain */ for (i = 0; i < pd->num_clks; i++) clk_prepare_enable(pd->clk[i]); /* Gate off domain when powered down */ @@ -123,10 +121,27 @@ static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd) udelay(DIV_ROUND_UP(sw + sw2iso, pd->ipg_rate_mhz)); /* Disable reset clocks for all devices in the domain */ for (i = 0; i < pd->num_clks; i++) clk_disable_unprepare(pd->clk[i]); +} + +static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd) +{ + struct imx_pm_domain *pd = to_imx_pm_domain(genpd); + int ret; + + if (pd->supply) { + ret = regulator_enable(pd->supply); + if (ret) { + pr_err("%s: failed to enable regulator: %d\n", + __func__, ret); + return ret; + } + } + + _imx6_pm_domain_power_on(genpd); return 0; } static int imx_pgc_get_clocks(struct device *dev, struct imx_pm_domain *domain) @@ -227,18 +242,45 @@ static int imx_pgc_power_domain_remove(struct platform_device *pdev) } return 0; } +static int imx_pgc_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_pm_domain *pd = pdev->dev.platform_data; + + if (pd->flags & PGC_DOMAIN_FLAG_NO_PD) + _imx6_pm_domain_power_off(&pd->base); + + return 0; +} + +static int imx_pgc_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct imx_pm_domain *pd = pdev->dev.platform_data; + + if (pd->flags & PGC_DOMAIN_FLAG_NO_PD) + _imx6_pm_domain_power_on(&pd->base); + + return 0; +} + +static const struct dev_pm_ops imx_pgc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(imx_pgc_suspend, imx_pgc_resume) +}; + static const struct platform_device_id imx_pgc_power_domain_id[] = { { "imx-pgc-power-domain"}, { }, }; static struct platform_driver imx_pgc_power_domain_driver = { .driver = { .name = "imx-pgc-pd", + .pm = &imx_pgc_pm_ops, }, .probe = imx_pgc_power_domain_probe, .remove = imx_pgc_power_domain_remove, .id_table = imx_pgc_power_domain_id, }; -- 2.17.1
