diff options
Diffstat (limited to 'drivers/soc/sunxi/sun20i-ppu.c')
| -rw-r--r-- | drivers/soc/sunxi/sun20i-ppu.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/soc/sunxi/sun20i-ppu.c b/drivers/soc/sunxi/sun20i-ppu.c new file mode 100644 index 000000000000..98cb41d36560 --- /dev/null +++ b/drivers/soc/sunxi/sun20i-ppu.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_domain.h> +#include <linux/reset.h> + +#define PD_STATE_ON 1 +#define PD_STATE_OFF 2 + +#define PD_RSTN_REG 0x00 +#define PD_CLK_GATE_REG 0x04 +#define PD_PWROFF_GATE_REG 0x08 +#define PD_PSW_ON_REG 0x0c +#define PD_PSW_OFF_REG 0x10 +#define PD_PSW_DELAY_REG 0x14 +#define PD_OFF_DELAY_REG 0x18 +#define PD_ON_DELAY_REG 0x1c +#define PD_COMMAND_REG 0x20 +#define PD_STATUS_REG 0x24 +#define PD_STATUS_COMPLETE BIT(1) +#define PD_STATUS_BUSY BIT(3) +#define PD_STATUS_STATE GENMASK(17, 16) +#define PD_ACTIVE_CTRL_REG 0x2c +#define PD_GATE_STATUS_REG 0x30 +#define PD_RSTN_STATUS BIT(0) +#define PD_CLK_GATE_STATUS BIT(1) +#define PD_PWROFF_GATE_STATUS BIT(2) +#define PD_PSW_STATUS_REG 0x34 + +#define PD_REGS_SIZE 0x80 + +struct sun20i_ppu_desc { + const char *const *names; + unsigned int num_domains; +}; + +struct sun20i_ppu_pd { + struct generic_pm_domain genpd; + void __iomem *base; +}; + +#define to_sun20i_ppu_pd(_genpd) \ + container_of(_genpd, struct sun20i_ppu_pd, genpd) + +static bool sun20i_ppu_pd_is_on(const struct sun20i_ppu_pd *pd) +{ + u32 status = readl(pd->base + PD_STATUS_REG); + + return FIELD_GET(PD_STATUS_STATE, status) == PD_STATE_ON; +} + +static int sun20i_ppu_pd_set_power(const struct sun20i_ppu_pd *pd, bool power_on) +{ + u32 state, status; + int ret; + + if (sun20i_ppu_pd_is_on(pd) == power_on) + return 0; + + /* Wait for the power controller to be idle. */ + ret = readl_poll_timeout(pd->base + PD_STATUS_REG, status, + !(status & PD_STATUS_BUSY), 100, 1000); + if (ret) + return ret; + + state = power_on ? PD_STATE_ON : PD_STATE_OFF; + writel(state, pd->base + PD_COMMAND_REG); + + /* Wait for the state transition to complete. */ + ret = readl_poll_timeout(pd->base + PD_STATUS_REG, status, + FIELD_GET(PD_STATUS_STATE, status) == state && + (status & PD_STATUS_COMPLETE), 100, 1000); + if (ret) + return ret; + + /* Clear the completion flag. */ + writel(status, pd->base + PD_STATUS_REG); + + return 0; +} + +static int sun20i_ppu_pd_power_on(struct generic_pm_domain *genpd) +{ + const struct sun20i_ppu_pd *pd = to_sun20i_ppu_pd(genpd); + + return sun20i_ppu_pd_set_power(pd, true); +} + +static int sun20i_ppu_pd_power_off(struct generic_pm_domain *genpd) +{ + const struct sun20i_ppu_pd *pd = to_sun20i_ppu_pd(genpd); + + return sun20i_ppu_pd_set_power(pd, false); +} + +static int sun20i_ppu_probe(struct platform_device *pdev) +{ + const struct sun20i_ppu_desc *desc; + struct device *dev = &pdev->dev; + struct genpd_onecell_data *ppu; + struct sun20i_ppu_pd *pds; + struct reset_control *rst; + void __iomem *base; + struct clk *clk; + int ret; + + desc = of_device_get_match_data(dev); + if (!desc) + return -EINVAL; + + pds = devm_kcalloc(dev, desc->num_domains, sizeof(*pds), GFP_KERNEL); + if (!pds) + return -ENOMEM; + + ppu = devm_kzalloc(dev, sizeof(*ppu), GFP_KERNEL); + if (!ppu) + return -ENOMEM; + + ppu->domains = devm_kcalloc(dev, desc->num_domains, + sizeof(*ppu->domains), GFP_KERNEL); + if (!ppu->domains) + return -ENOMEM; + + ppu->num_domains = desc->num_domains; + platform_set_drvdata(pdev, ppu); + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + rst = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(rst)) + return PTR_ERR(rst); + + ret = reset_control_deassert(rst); + if (ret) + return ret; + + for (unsigned int i = 0; i < ppu->num_domains; ++i) { + struct sun20i_ppu_pd *pd = &pds[i]; + + pd->genpd.name = desc->names[i]; + pd->genpd.power_off = sun20i_ppu_pd_power_off; + pd->genpd.power_on = sun20i_ppu_pd_power_on; + pd->base = base + PD_REGS_SIZE * i; + + ret = pm_genpd_init(&pd->genpd, NULL, sun20i_ppu_pd_is_on(pd)); + if (ret) { + dev_warn(dev, "Failed to add '%s' domain: %d\n", + pd->genpd.name, ret); + continue; + } + + ppu->domains[i] = &pd->genpd; + } + + ret = of_genpd_add_provider_onecell(dev->of_node, ppu); + if (ret) + dev_warn(dev, "Failed to add provider: %d\n", ret); + + return 0; +} + +static const char *const sun20i_d1_ppu_pd_names[] = { + "CPU", + "VE", + "DSP", +}; + +static const struct sun20i_ppu_desc sun20i_d1_ppu_desc = { + .names = sun20i_d1_ppu_pd_names, + .num_domains = ARRAY_SIZE(sun20i_d1_ppu_pd_names), +}; + +static const struct of_device_id sun20i_ppu_of_match[] = { + { + .compatible = "allwinner,sun20i-d1-ppu", + .data = &sun20i_d1_ppu_desc, + }, + { } +}; +MODULE_DEVICE_TABLE(of, sun20i_ppu_of_match); + +static struct platform_driver sun20i_ppu_driver = { + .probe = sun20i_ppu_probe, + .driver = { + .name = "sun20i-ppu", + .of_match_table = sun20i_ppu_of_match, + /* Power domains cannot be removed while they are in use. */ + .suppress_bind_attrs = true, + }, +}; +module_platform_driver(sun20i_ppu_driver); + +MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>"); +MODULE_DESCRIPTION("Allwinner D1 PPU power domain driver"); +MODULE_LICENSE("GPL"); |