pmdomain: sunxi: support power domain flags for pck600

While bringing up the PowerVR GPU on the A733 (Radxa Cubie A7Z), we
found that one of the GPU power domains must be configured as "always
on." While the Radxa BSP device tree leaves the GPU power domain nodes
commented out, the GPU driver code contains traces indicating an "always
on" requirement [1].

Currently, sunxi_pck600_desc only supports specifying pd_names. This
patch introduces sunxi_pck600_pd_desc, which stores both the name and
its associated flags. This also (more or less) aligns the implementation
with the existing sun50i PPU handling of always-on domains.

With this change, individual power domains can now be configured more
granularly. In particular, the GPU_CORE domain in sun60i_a733_pck600_pds
can now be explicitly marked with GENPD_FLAG_ALWAYS_ON.

The patch was tested on the Radxa Cubie A7Z, where the GPU now functions
as expected.

Thanks to Icenowy for her support and expertise on sunxi and PowerVR,
and thanks to Mikhail for identifying this exact cause of the GPU
bring-up issue.

[1] https://github.com/radxa/allwinner-bsp/blob/cubie-aiot-v1.4.6/modules/gpu/img-bxm/linux/rogue_km/services/system/rogue/rgx_sunxi/sunxi_platform.c#L62

Signed-off-by: Yuanshen Cao <alex.caoys@gmail.com>
Signed-off-by: Ulf Hansson <ulfh@kernel.org>

diff --git a/drivers/pmdomain/sunxi/sun55i-pck600.c b/drivers/pmdomain/sunxi/sun55i-pck600.c
index 1d47bbd35ced2c383de73e7f828976fe22fac2e9..8a37d11b65a2471d969f0f3dce9f8eefb856f9b4 100644 (file)
--- a/drivers/pmdomain/sunxi/sun55i-pck600.c
+++ b/drivers/pmdomain/sunxi/sun55i-pck600.c
@@ -41,8 +41,13 @@
 
 #define PPU_REG_SIZE   0x1000
 
+struct sunxi_pck600_pd_desc {
+       const char *name;
+       unsigned int flags;
+};
+
 struct sunxi_pck600_desc {
-       const char * const *pd_names;
+       const struct sunxi_pck600_pd_desc *pd_descs;
        unsigned int num_domains;
        u32 logic_power_switch0_delay_offset;
        u32 logic_power_switch1_delay_offset;
@@ -164,10 +169,12 @@ static int sunxi_pck600_probe(struct platform_device *pdev)
 
        for (i = 0; i < desc->num_domains; i++) {
                struct sunxi_pck600_pd *pd = &pck->pds[i];
+               const struct sunxi_pck600_pd_desc *pd_desc = &desc->pd_descs[i];
 
-               pd->genpd.name = desc->pd_names[i];
+               pd->genpd.name = pd_desc->name;
                pd->genpd.power_off = sunxi_pck600_power_off;
                pd->genpd.power_on = sunxi_pck600_power_on;
+               pd->genpd.flags = pd_desc->flags;
                pd->base = base + PPU_REG_SIZE * i;
 
                sunxi_pck600_pd_setup(pd, desc);
@@ -195,13 +202,14 @@ err_remove_pds:
        return ret;
 }
 
-static const char * const sun55i_a523_pck600_pd_names[] = {
-       "VE", "GPU", "VI", "VO0", "VO1", "DE", "NAND", "PCIE"
+static const struct sunxi_pck600_pd_desc sun55i_a523_pck600_pds[] = {
+       { "VE", }, { "GPU", }, { "VI", }, { "VO0", }, { "VO1", },
+       { "DE", }, { "NAND", }, { "PCIE", },
 };
 
 static const struct sunxi_pck600_desc sun55i_a523_pck600_desc = {
-       .pd_names = sun55i_a523_pck600_pd_names,
-       .num_domains = ARRAY_SIZE(sun55i_a523_pck600_pd_names),
+       .pd_descs = sun55i_a523_pck600_pds,
+       .num_domains = ARRAY_SIZE(sun55i_a523_pck600_pds),
        .logic_power_switch0_delay_offset = 0xc00,
        .logic_power_switch1_delay_offset = 0xc04,
        .off2on_delay_offset = 0xc10,
@@ -213,14 +221,15 @@ static const struct sunxi_pck600_desc sun55i_a523_pck600_desc = {
        .has_rst_clk = true,
 };
 
-static const char * const sun60i_a733_pck600_pd_names[] = {
-       "VI", "DE_SYS", "VE_DEC", "VE_ENC", "NPU",
-       "GPU_TOP", "GPU_CORE", "PCIE", "USB2", "VO", "VO1"
+static const struct sunxi_pck600_pd_desc sun60i_a733_pck600_pds[] = {
+       { "VI", }, { "DE_SYS", }, { "VE_DEC", }, { "VE_ENC", }, { "NPU", },
+       { "GPU_TOP", }, { "GPU_CORE", GENPD_FLAG_ALWAYS_ON },
+       { "PCIE", }, { "USB2", }, { "VO", }, { "VO1", },
 };
 
 static const struct sunxi_pck600_desc sun60i_a733_pck600_desc = {
-       .pd_names = sun60i_a733_pck600_pd_names,
-       .num_domains = ARRAY_SIZE(sun60i_a733_pck600_pd_names),
+       .pd_descs = sun60i_a733_pck600_pds,
+       .num_domains = ARRAY_SIZE(sun60i_a733_pck600_pds),
        .logic_power_switch0_delay_offset = 0xc00,
        .logic_power_switch1_delay_offset = 0xc04,
        .off2on_delay_offset = 0xc10,