Re: [PATCH 3/9] clk: qcom: gcc-msm8998: Control MMSS and GPUSS GPLL0 outputs properly

From: Jeffrey Hugo
Date: Mon Jun 26 2023 - 11:47:31 EST


On 6/22/2023 9:19 AM, Jeffrey Hugo wrote:
On 6/22/2023 9:05 AM, Konrad Dybcio wrote:
On 22.06.2023 16:55, Jeffrey Hugo wrote:
On 6/22/2023 5:57 AM, Konrad Dybcio wrote:
Up until now, we've been relying on some non-descript hardware magic
to pinkypromise turn the clocks on for us. While new SoCs shine with
that feature, MSM8998 can not always be fully trusted.

Register the MMSS and GPUSS GPLL0 legs with the CCF to allow for manual
enable voting.

Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
---
   drivers/clk/qcom/gcc-msm8998.c | 58 ++++++++++++++++++++++++++++++++++++++++++
   1 file changed, 58 insertions(+)

diff --git a/drivers/clk/qcom/gcc-msm8998.c b/drivers/clk/qcom/gcc-msm8998.c
index be024f8093c5..cccb19cae481 100644
--- a/drivers/clk/qcom/gcc-msm8998.c
+++ b/drivers/clk/qcom/gcc-msm8998.c
@@ -25,6 +25,9 @@
   #include "reset.h"
   #include "gdsc.h"
   +#define GCC_MMSS_MISC    0x0902C
+#define GCC_GPU_MISC    0x71028
+
   static struct pll_vco fabia_vco[] = {
       { 250000000, 2000000000, 0 },
       { 125000000, 1000000000, 1 },
@@ -1367,6 +1370,22 @@ static struct clk_branch gcc_boot_rom_ahb_clk = {
       },
   };
   +static struct clk_branch gcc_mmss_gpll0_div_clk = {
+    .halt_check = BRANCH_HALT_DELAY,
+    .clkr = {
+        .enable_reg = 0x5200c,
+        .enable_mask = BIT(0),
+        .hw.init = &(struct clk_init_data){
+            .name = "gcc_mmss_gpll0_div_clk",
+            .parent_hws = (const struct clk_hw *[]) {
+                &gpll0_out_main.clkr.hw,
+            },
+            .num_parents = 1,
+            .ops = &clk_branch2_ops,
+        },
+    },
+};
+
   static struct clk_branch gcc_mmss_gpll0_clk = {
       .halt_check = BRANCH_HALT_DELAY,
       .clkr = {
@@ -1395,6 +1414,38 @@ static struct clk_branch gcc_mss_gpll0_div_clk_src = {
       },
   };
   +static struct clk_branch gcc_gpu_gpll0_div_clk = {
+    .halt_check = BRANCH_HALT_DELAY,
+    .clkr = {
+        .enable_reg = 0x5200c,
+        .enable_mask = BIT(3),
+        .hw.init = &(struct clk_init_data){
+            .name = "gcc_gpu_gpll0_div_clk",
+            .parent_hws = (const struct clk_hw *[]) {
+                &gpll0_out_main.clkr.hw,
+            },
+            .num_parents = 1,
+            .ops = &clk_branch2_ops,
+        },
+    },
+};
+
+static struct clk_branch gcc_gpu_gpll0_clk = {
+    .halt_check = BRANCH_HALT_DELAY,
+    .clkr = {
+        .enable_reg = 0x5200c,
+        .enable_mask = BIT(4),
+        .hw.init = &(struct clk_init_data){
+            .name = "gcc_gpu_gpll0_clk",
+            .parent_hws = (const struct clk_hw *[]) {
+                &gpll0_out_main.clkr.hw,
+            },
+            .num_parents = 1,
+            .ops = &clk_branch2_ops,
+        },
+    },
+};
+
   static struct clk_branch gcc_blsp1_ahb_clk = {
       .halt_reg = 0x17004,
       .halt_check = BRANCH_HALT_VOTED,
@@ -3080,6 +3131,9 @@ static struct clk_regmap *gcc_msm8998_clocks[] = {
       [AGGRE2_SNOC_NORTH_AXI] = &aggre2_snoc_north_axi_clk.clkr,
       [SSC_XO] = &ssc_xo_clk.clkr,
       [SSC_CNOC_AHBS_CLK] = &ssc_cnoc_ahbs_clk.clkr,
+    [GCC_MMSS_GPLL0_DIV_CLK] = &gcc_mmss_gpll0_div_clk.clkr,
+    [GCC_GPU_GPLL0_DIV_CLK] = &gcc_gpu_gpll0_div_clk.clkr,
+    [GCC_GPU_GPLL0_CLK] = &gcc_gpu_gpll0_clk.clkr,
   };
     static struct gdsc *gcc_msm8998_gdscs[] = {
@@ -3235,6 +3289,10 @@ static int gcc_msm8998_probe(struct platform_device *pdev)
       if (ret)
           return ret;
   +    /* Disable the GPLL0 active input to MMSS and GPU via MISC registers */
+    regmap_write(regmap, GCC_MMSS_MISC, 0x10003);
+    regmap_write(regmap, GCC_GPU_MISC, 0x10003);

I wonder, does this disrupt a handoff of an active display from the bootloader to Linux?
My phone's bootloader doesn't initialize the display, if you (or Angelo
or Jami, +CC) could test this, it'd be wonderful.

Let me carve out some time to try it on the laptop.

Tested on the Lenovo Miix 630, and observed no issues.

Reviewed-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>

For patches 3-6 inclusive
Tested-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx>