// 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.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 <[email protected]>");
MODULE_DESCRIPTION("Allwinner D1 PPU power domain driver");
MODULE_LICENSE("GPL");
Codebase Browser
linux