On 2020-10-27 00:24, Jordan Crouse wrote:
>This is an extension to the series [1] to enable the System Cache (LLC)
>for
>Adreno a6xx targets.
>
>GPU targets with an MMU-500 attached have a slightly different process for
>enabling system cache. Use the compatible string on the IOMMU phandle
>to see if an MMU-500 is attached and modify the programming sequence
>accordingly.
>
>[1] https://patchwork.freedesktop.org/series/83037/
>
>Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
>---
>
> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 46 +++++++++++++++++++++------
> drivers/gpu/drm/msm/adreno/a6xx_gpu.h | 1 +
> 2 files changed, 37 insertions(+), 10 deletions(-)
>
>diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>index 95c98c642876..b7737732fbb6 100644
>--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>@@ -1042,6 +1042,8 @@ static void a6xx_llc_deactivate(struct a6xx_gpu
>*a6xx_gpu)
>
> static void a6xx_llc_activate(struct a6xx_gpu *a6xx_gpu)
> {
>+ struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
>+ struct msm_gpu *gpu = &adreno_gpu->base;
> u32 cntl1_regval = 0;
>
> if (IS_ERR(a6xx_gpu->llc_mmio))
>@@ -1055,11 +1057,17 @@ static void a6xx_llc_activate(struct a6xx_gpu
>*a6xx_gpu)
> (gpu_scid << 15) | (gpu_scid << 20);
> }
>
>+ /*
>+ * For targets with a MMU500, activate the slice but don't program the
>+ * register. The XBL will take care of that.
>+ */
> if (!llcc_slice_activate(a6xx_gpu->htw_llc_slice)) {
>- u32 gpuhtw_scid = llcc_get_slice_id(a6xx_gpu->htw_llc_slice);
>+ if (!a6xx_gpu->have_mmu500) {
>+ u32 gpuhtw_scid = llcc_get_slice_id(a6xx_gpu->htw_llc_slice);
>
>- gpuhtw_scid &= 0x1f;
>- cntl1_regval |= FIELD_PREP(GENMASK(29, 25), gpuhtw_scid);
>+ gpuhtw_scid &= 0x1f;
>+ cntl1_regval |= FIELD_PREP(GENMASK(29, 25), gpuhtw_scid);
>+ }
> }
>
> if (cntl1_regval) {
>@@ -1067,13 +1075,20 @@ static void a6xx_llc_activate(struct a6xx_gpu
>*a6xx_gpu)
> * Program the slice IDs for the various GPU blocks and GPU MMU
> * pagetables
> */
>- a6xx_llc_write(a6xx_gpu, REG_A6XX_CX_MISC_SYSTEM_CACHE_CNTL_1,
>cntl1_regval);
>-
>- /*
>- * Program cacheability overrides to not allocate cache lines on
>- * a write miss
>- */
>- a6xx_llc_rmw(a6xx_gpu, REG_A6XX_CX_MISC_SYSTEM_CACHE_CNTL_0, 0xF,
>0x03);
>+ if (a6xx_gpu->have_mmu500)
>+ gpu_rmw(gpu, REG_A6XX_GBIF_SCACHE_CNTL1, GENMASK(24, 0),
>+ cntl1_regval);
>+ else {
>+ a6xx_llc_write(a6xx_gpu,
>+ REG_A6XX_CX_MISC_SYSTEM_CACHE_CNTL_1, cntl1_regval);
>+
>+ /*
>+ * Program cacheability overrides to not allocate cache
>+ * lines on a write miss
>+ */
>+ a6xx_llc_rmw(a6xx_gpu,
>+ REG_A6XX_CX_MISC_SYSTEM_CACHE_CNTL_0, 0xF, 0x03);
>+ }
> }
> }
>
>@@ -1086,10 +1101,21 @@ static void a6xx_llc_slices_destroy(struct
>a6xx_gpu *a6xx_gpu)
> static void a6xx_llc_slices_init(struct platform_device *pdev,
> struct a6xx_gpu *a6xx_gpu)
> {
>+ struct device_node *phandle;
>+
> a6xx_gpu->llc_mmio = msm_ioremap(pdev, "cx_mem", "gpu_cx");
> if (IS_ERR(a6xx_gpu->llc_mmio))
> return;
>
>+ /*
>+ * There is a different programming path for targets with an mmu500
>+ * attached, so detect if that is the case
>+ */
>+ phandle = of_parse_phandle(pdev->dev.of_node, "iommus", 0);
>+ a6xx_gpu->have_mmu500 = (phandle &&
>+ of_device_is_compatible(phandle, "arm,mmu500"));
>+ of_node_put(phandle);
>+
> a6xx_gpu->llc_slice = llcc_slice_getd(LLCC_GPU);
> a6xx_gpu->htw_llc_slice = llcc_slice_getd(LLCC_GPUHTW);
>
>diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>index 9e6079af679c..e793d329e77b 100644
>--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>@@ -32,6 +32,7 @@ struct a6xx_gpu {
> void __iomem *llc_mmio;
> void *llc_slice;
> void *htw_llc_slice;
>+ bool have_mmu500;
> };
>
> #define to_a6xx_gpu(x) container_of(x, struct a6xx_gpu, base)
Thanks Jordan for the patch.
