1 // SPDX-License-Identifier: GPL-2.0-only
3 #include <linux/bitfield.h>
6 #include <linux/iopoll.h>
7 #include <linux/module.h>
8 #include <linux/of_device.h>
9 #include <linux/platform_device.h>
10 #include <linux/pm_domain.h>
11 #include <linux/reset.h>
14 #define PD_STATE_OFF 2
16 #define PD_RSTN_REG 0x00
17 #define PD_CLK_GATE_REG 0x04
18 #define PD_PWROFF_GATE_REG 0x08
19 #define PD_PSW_ON_REG 0x0c
20 #define PD_PSW_OFF_REG 0x10
21 #define PD_PSW_DELAY_REG 0x14
22 #define PD_OFF_DELAY_REG 0x18
23 #define PD_ON_DELAY_REG 0x1c
24 #define PD_COMMAND_REG 0x20
25 #define PD_STATUS_REG 0x24
26 #define PD_STATUS_COMPLETE BIT(1)
27 #define PD_STATUS_BUSY BIT(3)
28 #define PD_STATUS_STATE GENMASK(17, 16)
29 #define PD_ACTIVE_CTRL_REG 0x2c
30 #define PD_GATE_STATUS_REG 0x30
31 #define PD_RSTN_STATUS BIT(0)
32 #define PD_CLK_GATE_STATUS BIT(1)
33 #define PD_PWROFF_GATE_STATUS BIT(2)
34 #define PD_PSW_STATUS_REG 0x34
36 #define PD_REGS_SIZE 0x80
38 struct sun20i_ppu_desc {
39 const char *const *names;
40 unsigned int num_domains;
43 struct sun20i_ppu_pd {
44 struct generic_pm_domain genpd;
48 #define to_sun20i_ppu_pd(_genpd) \
49 container_of(_genpd, struct sun20i_ppu_pd, genpd)
51 static bool sun20i_ppu_pd_is_on(const struct sun20i_ppu_pd *pd)
53 u32 status = readl(pd->base + PD_STATUS_REG);
55 return FIELD_GET(PD_STATUS_STATE, status) == PD_STATE_ON;
58 static int sun20i_ppu_pd_set_power(const struct sun20i_ppu_pd *pd, bool power_on)
63 if (sun20i_ppu_pd_is_on(pd) == power_on)
66 /* Wait for the power controller to be idle. */
67 ret = readl_poll_timeout(pd->base + PD_STATUS_REG, status,
68 !(status & PD_STATUS_BUSY), 100, 1000);
72 state = power_on ? PD_STATE_ON : PD_STATE_OFF;
73 writel(state, pd->base + PD_COMMAND_REG);
75 /* Wait for the state transition to complete. */
76 ret = readl_poll_timeout(pd->base + PD_STATUS_REG, status,
77 FIELD_GET(PD_STATUS_STATE, status) == state &&
78 (status & PD_STATUS_COMPLETE), 100, 1000);
82 /* Clear the completion flag. */
83 writel(status, pd->base + PD_STATUS_REG);
88 static int sun20i_ppu_pd_power_on(struct generic_pm_domain *genpd)
90 const struct sun20i_ppu_pd *pd = to_sun20i_ppu_pd(genpd);
92 return sun20i_ppu_pd_set_power(pd, true);
95 static int sun20i_ppu_pd_power_off(struct generic_pm_domain *genpd)
97 const struct sun20i_ppu_pd *pd = to_sun20i_ppu_pd(genpd);
99 return sun20i_ppu_pd_set_power(pd, false);
102 static int sun20i_ppu_probe(struct platform_device *pdev)
104 const struct sun20i_ppu_desc *desc;
105 struct device *dev = &pdev->dev;
106 struct genpd_onecell_data *ppu;
107 struct sun20i_ppu_pd *pds;
108 struct reset_control *rst;
113 desc = of_device_get_match_data(dev);
117 pds = devm_kcalloc(dev, desc->num_domains, sizeof(*pds), GFP_KERNEL);
121 ppu = devm_kzalloc(dev, sizeof(*ppu), GFP_KERNEL);
125 ppu->domains = devm_kcalloc(dev, desc->num_domains,
126 sizeof(*ppu->domains), GFP_KERNEL);
130 ppu->num_domains = desc->num_domains;
131 platform_set_drvdata(pdev, ppu);
133 base = devm_platform_ioremap_resource(pdev, 0);
135 return PTR_ERR(base);
137 clk = devm_clk_get_enabled(dev, NULL);
141 rst = devm_reset_control_get_exclusive(dev, NULL);
145 ret = reset_control_deassert(rst);
149 for (unsigned int i = 0; i < ppu->num_domains; ++i) {
150 struct sun20i_ppu_pd *pd = &pds[i];
152 pd->genpd.name = desc->names[i];
153 pd->genpd.power_off = sun20i_ppu_pd_power_off;
154 pd->genpd.power_on = sun20i_ppu_pd_power_on;
155 pd->base = base + PD_REGS_SIZE * i;
157 ret = pm_genpd_init(&pd->genpd, NULL, sun20i_ppu_pd_is_on(pd));
159 dev_warn(dev, "Failed to add '%s' domain: %d\n",
160 pd->genpd.name, ret);
164 ppu->domains[i] = &pd->genpd;
167 ret = of_genpd_add_provider_onecell(dev->of_node, ppu);
169 dev_warn(dev, "Failed to add provider: %d\n", ret);
174 static const char *const sun20i_d1_ppu_pd_names[] = {
180 static const struct sun20i_ppu_desc sun20i_d1_ppu_desc = {
181 .names = sun20i_d1_ppu_pd_names,
182 .num_domains = ARRAY_SIZE(sun20i_d1_ppu_pd_names),
185 static const struct of_device_id sun20i_ppu_of_match[] = {
187 .compatible = "allwinner,sun20i-d1-ppu",
188 .data = &sun20i_d1_ppu_desc,
192 MODULE_DEVICE_TABLE(of, sun20i_ppu_of_match);
194 static struct platform_driver sun20i_ppu_driver = {
195 .probe = sun20i_ppu_probe,
197 .name = "sun20i-ppu",
198 .of_match_table = sun20i_ppu_of_match,
199 /* Power domains cannot be removed while they are in use. */
200 .suppress_bind_attrs = true,
203 module_platform_driver(sun20i_ppu_driver);
205 MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>");
206 MODULE_DESCRIPTION("Allwinner D1 PPU power domain driver");
207 MODULE_LICENSE("GPL");