Am Donnerstag, den 13.02.2014, 15:39 +0100 schrieb Philipp Zabel: > When generic pm domain support is enabled, the PGC can be used > to completely gate power to the PU power domain containing GPU3D, > GPU2D, and VPU cores. > This code triggers the PGC powerdown sequence to disable the GPU/VPU > isolation cells and gate power and then disables the PU regulator. > To reenable, the reverse powerup sequence is triggered after the PU > regulaotor is enabled again. > > Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> > --- > Changes since v1: > - Removed superfluous comment > - Link PU domain with its DT node, check for PU domain in bus notifier > - Turn off the PU power domain on boot > --- > arch/arm/mach-imx/Kconfig | 2 + > arch/arm/mach-imx/gpc.c | 170 ++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 172 insertions(+) > > diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig > index 33567aa..3c58f2e 100644 > --- a/arch/arm/mach-imx/Kconfig > +++ b/arch/arm/mach-imx/Kconfig > @@ -808,6 +808,7 @@ config SOC_IMX6Q > select PL310_ERRATA_727915 if CACHE_PL310 > select PL310_ERRATA_769419 if CACHE_PL310 > select PM_OPP if PM > + select PM_GENERIC_DOMAINS if PM > > help > This enables support for Freescale i.MX6 Quad processor. > @@ -827,6 +828,7 @@ config SOC_IMX6SL > select PL310_ERRATA_588369 if CACHE_PL310 > select PL310_ERRATA_727915 if CACHE_PL310 > select PL310_ERRATA_769419 if CACHE_PL310 > + select PM_GENERIC_DOMAINS if PM > > help > This enables support for Freescale i.MX6 SoloLite processor. > diff --git a/arch/arm/mach-imx/gpc.c b/arch/arm/mach-imx/gpc.c > index 586e017..1dc4301 100644 > --- a/arch/arm/mach-imx/gpc.c > +++ b/arch/arm/mach-imx/gpc.c > @@ -10,19 +10,32 @@ > * http://www.gnu.org/copyleft/gpl.html > */ > > +#include <linux/clk.h> > +#include <linux/delay.h> > #include <linux/io.h> > #include <linux/irq.h> > #include <linux/of.h> > #include <linux/of_address.h> > #include <linux/of_irq.h> > +#include <linux/platform_device.h> > +#include <linux/pm_domain.h> > +#include <linux/regulator/consumer.h> > #include <linux/irqchip/arm-gic.h> > #include "common.h" > +#include "hardware.h" > > +#define GPC_CNTR 0x000 > #define GPC_IMR1 0x008 > +#define GPC_PGC_GPU_PDN 0x260 > +#define GPC_PGC_GPU_PUPSCR 0x264 > +#define GPC_PGC_GPU_PDNSCR 0x268 > #define GPC_PGC_CPU_PDN 0x2a0 > > #define IMR_NUM 4 > > +#define GPU_VPU_PUP_REQ BIT(1) > +#define GPU_VPU_PDN_REQ BIT(0) > + > static void __iomem *gpc_base; > static u32 gpc_wake_irqs[IMR_NUM]; > static u32 gpc_saved_imrs[IMR_NUM]; > @@ -138,3 +151,160 @@ void __init imx_gpc_init(void) > gic_arch_extn.irq_unmask = imx_gpc_irq_unmask; > gic_arch_extn.irq_set_wake = imx_gpc_irq_set_wake; > } > + > +static struct regulator *pu_reg; > + > +static int imx6q_pm_pu_power_off(struct generic_pm_domain *genpd) > +{ > + u32 val; > + int iso, iso2sw; > + > + /* Read ISO and ISO2SW power down delays */ > + val = readl_relaxed(gpc_base + GPC_PGC_GPU_PDNSCR); > + iso = val & 0x3f; > + iso2sw = (val >> 8) & 0x3f; > + > + /* Gate off PU domain when GPU/VPU when powered down */ > + writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN); > + > + /* Request GPC to power down GPU/VPU */ > + val = readl_relaxed(gpc_base + GPC_CNTR); > + val |= GPU_VPU_PDN_REQ; > + writel_relaxed(val, gpc_base + GPC_CNTR); > + > + /* Wait ISO + ISO2SW IPG clock cycles */ > + ndelay((iso + iso2sw) * 1000 / 66); > + > + regulator_disable(pu_reg); > + > + return 0; > +} > + > +static int imx6q_pm_pu_power_on(struct generic_pm_domain *genpd) > +{ > + int ret; > + u32 val; > + int sw, sw2iso; > + > + ret = regulator_enable(pu_reg); > + if (ret) { > + pr_err("%s: failed to enable regulator: %d\n", __func__, ret); > + return ret; > + } > + > + /* Gate off PU domain when GPU/VPU when powered down */ > + writel_relaxed(0x1, gpc_base + GPC_PGC_GPU_PDN); > + > + /* Read ISO and ISO2SW power down delays */ > + val = readl_relaxed(gpc_base + GPC_PGC_GPU_PUPSCR); > + sw = val & 0x3f; > + sw2iso = (val >> 8) & 0x3f; > + > + /* Request GPC to power up GPU/VPU */ > + val = readl_relaxed(gpc_base + GPC_CNTR); > + val |= GPU_VPU_PUP_REQ; > + writel_relaxed(val, gpc_base + GPC_CNTR); > + > + /* Wait ISO + ISO2SW IPG clock cycles */ > + ndelay((sw + sw2iso) * 1000 / 66); > + > + return 0; > +} > + > +static struct generic_pm_domain imx6q_pu_domain = { > + .name = "PU", > + .power_off = imx6q_pm_pu_power_off, > + .power_on = imx6q_pm_pu_power_on, > +}; > + > +static int imx6q_pm_notifier_call(struct notifier_block *nb, > + unsigned long event, void *data) > +{ > + struct generic_pm_domain *genpd; > + struct device *dev = data; > + struct device_node *np; > + int ret; > + > + switch (event) { > + case BUS_NOTIFY_BIND_DRIVER: > + np = of_parse_phandle(dev->of_node, "power-domain", 0); > + if (!np || np != imx6q_pu_domain.of_node) > + return NOTIFY_DONE; > + > + ret = pm_genpd_of_add_device(np, dev); > + if (ret) > + dev_err(dev, "failed to add to power domain: %d\n", > + ret); > + break; > + case BUS_NOTIFY_UNBOUND_DRIVER: > + genpd = dev_to_genpd(dev); > + if (IS_ERR(genpd) || genpd != &imx6q_pu_domain) > + return NOTIFY_DONE; > + > + ret = pm_genpd_remove_device(genpd, dev); > + if (ret) > + dev_err(dev, "failed to remove from power domain: %d\n", > + ret); > + break; > + } > + > + return NOTIFY_DONE; > +} > + > +static struct notifier_block imx6q_platform_nb = { > + .notifier_call = imx6q_pm_notifier_call, > +}; > + > +static int imx_gpc_probe(struct platform_device *pdev) > +{ > + struct device_node *np; > + int ret; > + > + np = of_get_child_by_name(pdev->dev.of_node, "pu-power-domain"); > + if (!np) { > + dev_err(&pdev->dev, "missing pu-power-domain node\n"); > + return -EINVAL; > + } > + imx6q_pu_domain.of_node = np; > + > + pu_reg = devm_regulator_get(&pdev->dev, "pu"); > + if (IS_ERR(pu_reg)) { > + ret = PTR_ERR(pu_reg); > + dev_err(&pdev->dev, "failed to get pu regulator: %d\n", ret); > + return ret; > + } > + > + /* The regulator is initially enabled */ > + ret = regulator_enable(pu_reg); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to enable pu regulator: %d\n", ret); > + return ret; > + } > + > + imx6q_pu_domain.of_node = np; > + imx6q_pm_pu_power_off(&imx6q_pu_domain); > + pm_genpd_init(&imx6q_pu_domain, NULL, true); Turning off the PU power domain and supply voltage on boot isn't a good idea if the kernel doesn't have runtime PM support compiled in. In that case it should be left enabled: --- a/arch/arm/mach-imx/gpc.c +++ b/arch/arm/mach-imx/gpc.c @@ -366,8 +366,12 @@ static int imx_gpc_probe(struct platform_device *pdev) regulator_allow_bypass(pu_reg, true); imx6q_pu_domain.of_node = np; +#ifdef CONFIG_PM_RUNTIME imx6q_pm_pu_power_off(&imx6q_pu_domain); pm_genpd_init(&imx6q_pu_domain, NULL, true); +#else + pm_genpd_init(&imx6q_pu_domain, NULL, false); +#endif bus_register_notifier(&platform_bus_type, &imx6q_platform_nb); return 0; > + bus_register_notifier(&platform_bus_type, &imx6q_platform_nb); > + > + return 0; > +} > + > +static struct of_device_id imx_gpc_dt_ids[] = { > + { .compatible = "fsl,imx6q-gpc" }, > + { } > +}; > + > +static struct platform_driver imx_gpc_driver = { > + .driver = { > + .name = "imx-gpc", > + .owner = THIS_MODULE, > + .of_match_table = imx_gpc_dt_ids, > + }, > + .probe = imx_gpc_probe, > +}; > + > +static int __init imx_pgc_init(void) > +{ > + return platform_driver_register(&imx_gpc_driver); > +} > +subsys_initcall(imx_pgc_init); regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
