Re: [PATCH v3 4/6] drm/msm/a7xx: Initialize a750 "software fuse"

2024-04-30 Thread Konrad Dybcio
On 30.04.2024 12:43 PM, Connor Abbott wrote:
> On all Qualcomm platforms with a7xx GPUs, qcom_scm provides a method to
> initialize cx_mem. Copy this from downstream (minus BCL which we
> currently don't support). On a750, this includes a new "fuse" register
> which can be used by qcom_scm to fuse off certain features like
> raytracing in software. The fuse is default off, and is initialized by
> calling the method. Afterwards we have to read it to find out which
> features were enabled.
> 
> Reviewed-by: Dmitry Baryshkov 
> Signed-off-by: Connor Abbott 
> ---

Reviewed-by: Konrad Dybcio 

Konrad


[PATCH v3 4/6] drm/msm/a7xx: Initialize a750 "software fuse"

2024-04-30 Thread Connor Abbott
On all Qualcomm platforms with a7xx GPUs, qcom_scm provides a method to
initialize cx_mem. Copy this from downstream (minus BCL which we
currently don't support). On a750, this includes a new "fuse" register
which can be used by qcom_scm to fuse off certain features like
raytracing in software. The fuse is default off, and is initialized by
calling the method. Afterwards we have to read it to find out which
features were enabled.

Reviewed-by: Dmitry Baryshkov 
Signed-off-by: Connor Abbott 
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu.c   | 91 -
 drivers/gpu/drm/msm/adreno/adreno_gpu.h |  2 +
 2 files changed, 92 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c 
b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index cf0b1de1c071..52b080206090 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -10,6 +10,7 @@
 
 #include 
 #include 
+#include 
 #include 
 #include 
 
@@ -1686,7 +1687,8 @@ static int a6xx_zap_shader_init(struct msm_gpu *gpu)
   A6XX_RBBM_INT_0_MASK_RBBM_HANG_DETECT | \
   A6XX_RBBM_INT_0_MASK_UCHE_OOB_ACCESS | \
   A6XX_RBBM_INT_0_MASK_UCHE_TRAP_INTR | \
-  A6XX_RBBM_INT_0_MASK_TSBWRITEERROR)
+  A6XX_RBBM_INT_0_MASK_TSBWRITEERROR | \
+  A6XX_RBBM_INT_0_MASK_SWFUSEVIOLATION)
 
 #define A7XX_APRIV_MASK (A6XX_CP_APRIV_CNTL_ICACHE | \
 A6XX_CP_APRIV_CNTL_RBFETCH | \
@@ -2356,6 +2358,27 @@ static void a6xx_fault_detect_irq(struct msm_gpu *gpu)
kthread_queue_work(gpu->worker, >recover_work);
 }
 
+static void a7xx_sw_fuse_violation_irq(struct msm_gpu *gpu)
+{
+   u32 status;
+
+   status = gpu_read(gpu, REG_A7XX_RBBM_SW_FUSE_INT_STATUS);
+   gpu_write(gpu, REG_A7XX_RBBM_SW_FUSE_INT_MASK, 0);
+
+   dev_err_ratelimited(>pdev->dev, "SW fuse violation 
status=%8.8x\n", status);
+
+   /*
+* Ignore FASTBLEND violations, because the HW will silently fall back
+* to legacy blending.
+*/
+   if (status & (A7XX_CX_MISC_SW_FUSE_VALUE_RAYTRACING |
+ A7XX_CX_MISC_SW_FUSE_VALUE_LPAC)) {
+   del_timer(>hangcheck_timer);
+
+   kthread_queue_work(gpu->worker, >recover_work);
+   }
+}
+
 static irqreturn_t a6xx_irq(struct msm_gpu *gpu)
 {
struct msm_drm_private *priv = gpu->dev->dev_private;
@@ -2384,6 +2407,9 @@ static irqreturn_t a6xx_irq(struct msm_gpu *gpu)
if (status & A6XX_RBBM_INT_0_MASK_UCHE_OOB_ACCESS)
dev_err_ratelimited(>pdev->dev, "UCHE | Out of bounds 
access\n");
 
+   if (status & A6XX_RBBM_INT_0_MASK_SWFUSEVIOLATION)
+   a7xx_sw_fuse_violation_irq(gpu);
+
if (status & A6XX_RBBM_INT_0_MASK_CP_CACHE_FLUSH_TS)
msm_gpu_retire(gpu);
 
@@ -2525,6 +2551,61 @@ static void a6xx_llc_slices_init(struct platform_device 
*pdev,
a6xx_gpu->llc_mmio = ERR_PTR(-EINVAL);
 }
 
+static int a7xx_cx_mem_init(struct a6xx_gpu *a6xx_gpu)
+{
+   struct adreno_gpu *adreno_gpu = _gpu->base;
+   struct msm_gpu *gpu = _gpu->base;
+   u32 fuse_val;
+   int ret;
+
+   if (adreno_is_a750(adreno_gpu)) {
+   /*
+* Assume that if qcom scm isn't available, that whatever
+* replacement allows writing the fuse register ourselves.
+* Users of alternative firmware need to make sure this
+* register is writeable or indicate that it's not somehow.
+* Print a warning because if you mess this up you're about to
+* crash horribly.
+*/
+   if (!qcom_scm_is_available()) {
+   dev_warn_once(gpu->dev->dev,
+   "SCM is not available, poking fuse register\n");
+   a6xx_llc_write(a6xx_gpu, REG_A7XX_CX_MISC_SW_FUSE_VALUE,
+   A7XX_CX_MISC_SW_FUSE_VALUE_RAYTRACING |
+   A7XX_CX_MISC_SW_FUSE_VALUE_FASTBLEND |
+   A7XX_CX_MISC_SW_FUSE_VALUE_LPAC);
+   adreno_gpu->has_ray_tracing = true;
+   return 0;
+   }
+
+   ret = qcom_scm_gpu_init_regs(QCOM_SCM_GPU_ALWAYS_EN_REQ |
+QCOM_SCM_GPU_TSENSE_EN_REQ);
+   if (ret)
+   return ret;
+
+   /*
+* On a750 raytracing may be disabled by the firmware, find out
+* whether that's the case. The scm call above sets the fuse
+* register.
+*/
+   fuse_val = a6xx_llc_read(a6xx_gpu,
+REG_A7XX_CX_MISC_SW_FUSE_VALUE);
+   adreno_gpu->has_ray_tracing =
+   !!(fuse_val &