diff options
Diffstat (limited to 'drivers/soc/imx/gpc.c')
| -rw-r--r-- | drivers/soc/imx/gpc.c | 487 |
1 files changed, 487 insertions, 0 deletions
diff --git a/drivers/soc/imx/gpc.c b/drivers/soc/imx/gpc.c new file mode 100644 index 000000000000..1e9b3b81f466 --- /dev/null +++ b/drivers/soc/imx/gpc.c @@ -0,0 +1,487 @@ +/* + * Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de> + * Copyright 2011-2013 Freescale Semiconductor, Inc. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_domain.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> + +#define GPC_CNTR 0x000 + +#define GPC_PGC_PDN_OFFS 0x0 +#define GPC_PGC_PUPSCR_OFFS 0x4 +#define GPC_PGC_PDNSCR_OFFS 0x8 +#define GPC_PGC_SW2ISO_SHIFT 0x8 +#define GPC_PGC_SW_SHIFT 0x0 + +#define GPC_PGC_GPU_PDN 0x260 +#define GPC_PGC_GPU_PUPSCR 0x264 +#define GPC_PGC_GPU_PDNSCR 0x268 + +#define GPU_VPU_PUP_REQ BIT(1) +#define GPU_VPU_PDN_REQ BIT(0) + +#define GPC_CLK_MAX 6 + +struct imx_pm_domain { + struct generic_pm_domain base; + struct regmap *regmap; + struct regulator *supply; + struct clk *clk[GPC_CLK_MAX]; + int num_clks; + unsigned int reg_offs; + signed char cntr_pdn_bit; + unsigned int ipg_rate_mhz; +}; + +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) +{ + struct imx_pm_domain *pd = to_imx_pm_domain(genpd); + int iso, iso2sw; + u32 val; + + /* 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; + + /* Gate off domain when powered down */ + regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_PDN_OFFS, + 0x1, 0x1); + + /* Request GPC to power down domain */ + 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)); + + if (pd->supply) + regulator_disable(pd->supply); + + return 0; +} + +static int 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; + 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 */ + regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_PDN_OFFS, + 0x1, 0x1); + + /* Read ISO and ISO2SW power down delays */ + regmap_read(pd->regmap, pd->reg_offs + GPC_PGC_PUPSCR_OFFS, &val); + sw = val & 0x3f; + sw2iso = (val >> 8) & 0x3f; + + /* Request GPC to power up domain */ + val = BIT(pd->cntr_pdn_bit + 1); + regmap_update_bits(pd->regmap, GPC_CNTR, val, val); + + /* Wait ISO + ISO2SW IPG clock cycles */ + 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]); + + return 0; +} + +static int imx_pgc_get_clocks(struct device *dev, struct imx_pm_domain *domain) +{ + int i, ret; + + for (i = 0; ; i++) { + struct clk *clk = of_clk_get(dev->of_node, i); + if (IS_ERR(clk)) + break; + if (i >= GPC_CLK_MAX) { + dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX); + ret = -EINVAL; + goto clk_err; + } + domain->clk[i] = clk; + } + domain->num_clks = i; + + return 0; + +clk_err: + for (; i >= 0; i--) + clk_put(domain->clk[i]); + + return ret; +} + +static void imx_pgc_put_clocks(struct imx_pm_domain *domain) +{ + int i; + + for (i = domain->num_clks - 1; i >= 0; i--) + clk_put(domain->clk[i]); +} + +static int imx_pgc_parse_dt(struct device *dev, struct imx_pm_domain *domain) +{ + /* try to get the domain supply regulator */ + domain->supply = devm_regulator_get_optional(dev, "power"); + if (IS_ERR(domain->supply)) { + if (PTR_ERR(domain->supply) == -ENODEV) + domain->supply = NULL; + else + return PTR_ERR(domain->supply); + } + + /* try to get all clocks needed for reset propagation */ + return imx_pgc_get_clocks(dev, domain); +} + +static int imx_pgc_power_domain_probe(struct platform_device *pdev) +{ + struct imx_pm_domain *domain = pdev->dev.platform_data; + struct device *dev = &pdev->dev; + int ret; + + /* if this PD is associated with a DT node try to parse it */ + if (dev->of_node) { + ret = imx_pgc_parse_dt(dev, domain); + if (ret) + return ret; + } + + /* initially power on the domain */ + if (domain->base.power_on) + domain->base.power_on(&domain->base); + + if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) { + pm_genpd_init(&domain->base, NULL, false); + ret = of_genpd_add_provider_simple(dev->of_node, &domain->base); + if (ret) + goto genpd_err; + } + + device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE); + + return 0; + +genpd_err: + pm_genpd_remove(&domain->base); + imx_pgc_put_clocks(domain); + + return ret; +} + +static int imx_pgc_power_domain_remove(struct platform_device *pdev) +{ + struct imx_pm_domain *domain = pdev->dev.platform_data; + + if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) { + of_genpd_del_provider(pdev->dev.of_node); + pm_genpd_remove(&domain->base); + imx_pgc_put_clocks(domain); + } + + return 0; +} + +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", + }, + .probe = imx_pgc_power_domain_probe, + .remove = imx_pgc_power_domain_remove, + .id_table = imx_pgc_power_domain_id, +}; +builtin_platform_driver(imx_pgc_power_domain_driver) + +static struct genpd_power_state imx6_pm_domain_pu_state = { + .power_off_latency_ns = 25000, + .power_on_latency_ns = 2000000, +}; + +static struct imx_pm_domain imx_gpc_domains[] = { + { + .base = { + .name = "ARM", + }, + }, { + .base = { + .name = "PU", + .power_off = imx6_pm_domain_power_off, + .power_on = imx6_pm_domain_power_on, + .states = &imx6_pm_domain_pu_state, + .state_count = 1, + }, + .reg_offs = 0x260, + .cntr_pdn_bit = 0, + }, { + .base = { + .name = "DISPLAY", + .power_off = imx6_pm_domain_power_off, + .power_on = imx6_pm_domain_power_on, + }, + .reg_offs = 0x240, + .cntr_pdn_bit = 4, + } +}; + +struct imx_gpc_dt_data { + int num_domains; +}; + +static const struct imx_gpc_dt_data imx6q_dt_data = { + .num_domains = 2, +}; + +static const struct imx_gpc_dt_data imx6sl_dt_data = { + .num_domains = 3, +}; + +static const struct of_device_id imx_gpc_dt_ids[] = { + { .compatible = "fsl,imx6q-gpc", .data = &imx6q_dt_data }, + { .compatible = "fsl,imx6sl-gpc", .data = &imx6sl_dt_data }, + { } +}; + +static bool imx_gpc_readable_reg(struct device *dev, unsigned int reg) +{ + return (reg % 4 == 0) && (reg <= 0x2ac); +} + +static bool imx_gpc_volatile_reg(struct device *dev, unsigned int reg) +{ + if (reg == GPC_CNTR) + return true; + + return false; +} + +static const struct regmap_config imx_gpc_regmap_config = { + .cache_type = REGCACHE_FLAT, + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, + + .readable_reg = imx_gpc_readable_reg, + .volatile_reg = imx_gpc_volatile_reg, + + .max_register = 0x2ac, +}; + +static struct generic_pm_domain *imx_gpc_onecell_domains[] = { + &imx_gpc_domains[0].base, + &imx_gpc_domains[1].base, +}; + +static struct genpd_onecell_data imx_gpc_onecell_data = { + .domains = imx_gpc_onecell_domains, + .num_domains = 2, +}; + +static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap) +{ + struct imx_pm_domain *domain; + int i, ret; + + for (i = 0; i < 2; i++) { + domain = &imx_gpc_domains[i]; + domain->regmap = regmap; + domain->ipg_rate_mhz = 66; + + if (i == 1) { + domain->supply = devm_regulator_get(dev, "pu"); + if (IS_ERR(domain->supply)) + return PTR_ERR(domain->supply);; + + ret = imx_pgc_get_clocks(dev, domain); + if (ret) + goto clk_err; + + domain->base.power_on(&domain->base); + } + } + + for (i = 0; i < 2; i++) + pm_genpd_init(&imx_gpc_domains[i].base, NULL, false); + + if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) { + ret = of_genpd_add_provider_onecell(dev->of_node, + &imx_gpc_onecell_data); + if (ret) + goto genpd_err; + } + + return 0; + +genpd_err: + for (i = 0; i < 2; i++) + pm_genpd_remove(&imx_gpc_domains[i].base); + imx_pgc_put_clocks(&imx_gpc_domains[1]); +clk_err: + return ret; +} + +static int imx_gpc_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id = + of_match_device(imx_gpc_dt_ids, &pdev->dev); + const struct imx_gpc_dt_data *of_id_data = of_id->data; + struct device_node *pgc_node; + struct regmap *regmap; + struct resource *res; + void __iomem *base; + int ret; + + pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc"); + + /* bail out if DT too old and doesn't provide the necessary info */ + if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") && + !pgc_node) + return 0; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base, + &imx_gpc_regmap_config); + if (IS_ERR(regmap)) { + ret = PTR_ERR(regmap); + dev_err(&pdev->dev, "failed to init regmap: %d\n", + ret); + return ret; + } + + if (!pgc_node) { + /* old DT layout is only supported for mx6q aka 2 domains */ + if (of_id_data->num_domains != 2) { + dev_err(&pdev->dev, "could not find pgc DT node\n"); + return -ENODEV; + } + + ret = imx_gpc_old_dt_init(&pdev->dev, regmap); + if (ret) + return ret; + } else { + struct imx_pm_domain *domain; + struct platform_device *pd_pdev; + struct device_node *np; + struct clk *ipg_clk; + unsigned int ipg_rate_mhz; + int domain_index; + + ipg_clk = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(ipg_clk)) + return PTR_ERR(ipg_clk); + ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000; + + for_each_child_of_node(pgc_node, np) { + ret = of_property_read_u32(np, "reg", &domain_index); + if (ret) { + of_node_put(np); + return ret; + } + if (domain_index >= ARRAY_SIZE(imx_gpc_domains)) + continue; + + domain = &imx_gpc_domains[domain_index]; + domain->regmap = regmap; + domain->ipg_rate_mhz = ipg_rate_mhz; + + pd_pdev = platform_device_alloc("imx-pgc-power-domain", + domain_index); + if (!pd_pdev) { + of_node_put(np); + return -ENOMEM; + } + pd_pdev->dev.platform_data = domain; + pd_pdev->dev.parent = &pdev->dev; + pd_pdev->dev.of_node = np; + + ret = platform_device_add(pd_pdev); + if (ret) { + platform_device_put(pd_pdev); + of_node_put(np); + return ret; + } + } + } + + return 0; +} + +static int imx_gpc_remove(struct platform_device *pdev) +{ + int ret; + + /* + * If the old DT binding is used the toplevel driver needs to + * de-register the power domains + */ + if (!of_get_child_by_name(pdev->dev.of_node, "pgc")) { + of_genpd_del_provider(pdev->dev.of_node); + + ret = pm_genpd_remove(&imx_gpc_domains[1].base); + if (ret) + return ret; + imx_pgc_put_clocks(&imx_gpc_domains[1]); + + ret = pm_genpd_remove(&imx_gpc_domains[0].base); + if (ret) + return ret; + } + + return 0; +} + +static struct platform_driver imx_gpc_driver = { + .driver = { + .name = "imx-gpc", + .of_match_table = imx_gpc_dt_ids, + }, + .probe = imx_gpc_probe, + .remove = imx_gpc_remove, +}; +builtin_platform_driver(imx_gpc_driver) |