Re: [RFC PATCH 1/1] clk: sunxi-ng: h6-r: add GPU power domain

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
---
 drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c | 84 ++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c b/drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c
index 02b28cfc5525e..363fb7a71e9f5 100644
--- a/drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c
+++ b/drivers/clk/sunxi-ng/ccu-sun50i-h6-r.c

@@ -4,9 +4,11 @@
  */

 #include <linux/clk-provider.h>
+#include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_domain.h>

 #include "ccu_common.h"
 #include "ccu_reset.h"

@@ -217,6 +219,86 @@ static const struct sunxi_ccu_desc sun50i_h616_r_ccu_desc = {
        .num_resets     = ARRAY_SIZE(sun50i_h616_r_ccu_resets),
 };

+#define        PD_H616_GPU_REG                 0x254
+
+struct sun50i_h616_ppu_pd {
+       struct generic_pm_domain        genpd;
+       void __iomem                    *base;
+};
+
+#define to_sun50i_h616_ppu_pd(_genpd) \
+       container_of(_genpd, struct sun50i_h616_ppu_pd, genpd)
+
+static bool sun50i_h616_ppu_power_status(const struct sun50i_h616_ppu_pd *pd)
+{
+       return !readl(pd->base + PD_H616_GPU_REG);
+}
+
+static int sun50i_h616_ppu_pd_set_power(const struct sun50i_h616_ppu_pd *pd,
+                                       bool power_on)
+{
+       if (power_on)
+               writel(0, pd->base + PD_H616_GPU_REG);
+       else
+               writel(1, pd->base + PD_H616_GPU_REG);
+
+       return 0;
+}
+
+static int sun50i_h616_ppu_pd_power_on(struct generic_pm_domain *genpd)
+{
+       const struct sun50i_h616_ppu_pd *pd = to_sun50i_h616_ppu_pd(genpd);
+
+       return sun50i_h616_ppu_pd_set_power(pd, true);
+}
+
+static int sun50i_h616_ppu_pd_power_off(struct generic_pm_domain *genpd)
+{
+       const struct sun50i_h616_ppu_pd *pd = to_sun50i_h616_ppu_pd(genpd);
+
+       return sun50i_h616_ppu_pd_set_power(pd, false);
+}
+
+static int sun50i_h616_register_ppu(struct platform_device *pdev,
+                                   void __iomem *base)
+{
+       struct device *dev = &pdev->dev;
+       struct genpd_onecell_data *ppu;
+       struct sun50i_h616_ppu_pd *pd;
+       int ret;
+
+       pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+       if (!pd)
+               return -ENOMEM;
+
+       ppu = devm_kzalloc(dev, sizeof(*ppu), GFP_KERNEL);
+       if (!ppu)
+               return -ENOMEM;
+
+       ppu->domains = devm_kzalloc(dev, sizeof(*ppu->domains), GFP_KERNEL);
+       if (!ppu->domains)
+               return -ENOMEM;
+
+       ppu->num_domains = 1;
+       pd->genpd.name          = "GPU";
+       pd->genpd.power_off     = sun50i_h616_ppu_pd_power_off;
+       pd->genpd.power_on      = sun50i_h616_ppu_pd_power_on;
+       pd->base                = base;
+
+       ret = pm_genpd_init(&pd->genpd, NULL, !sun50i_h616_ppu_power_status(pd));
+       if (ret) {
+               dev_warn(dev, "Failed to add GPU power domain: %d\n", ret);
+               return ret;
+       }
+
+       ppu->domains[0] = &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 int sun50i_h6_r_ccu_probe(struct platform_device *pdev)
 {
        const struct sunxi_ccu_desc *desc;

@@ -230,6 +312,8 @@ static int sun50i_h6_r_ccu_probe(struct platform_device *pdev)
        if (IS_ERR(reg))
                return PTR_ERR(reg);

+       sun50i_h616_register_ppu(pdev, reg);
+
        return devm_sunxi_ccu_probe(&pdev->dev, reg, desc);
 }