On Wed, Apr 9, 2025 at 10:48 AM Konrad Dybcio <konradyb...@kernel.org> wrote:
>
> From: Konrad Dybcio <konrad.dyb...@oss.qualcomm.com>
>
> The Highest Bank address Bit value can change based on memory type used.
>
> Attempt to retrieve it dynamically, and fall back to a reasonable
> default (the one used prior to this change) on error.
>
> Signed-off-by: Konrad Dybcio <konrad.dyb...@oss.qualcomm.com>
> ---
> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 22 ++++++++++++++++------
> 1 file changed, 16 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> index
> 06465bc2d0b4b128cddfcfcaf1fe4252632b6777..0cc397378c99db35315209d0265ad9223e8b55c7
> 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> @@ -13,6 +13,7 @@
> #include <linux/firmware/qcom/qcom_scm.h>
> #include <linux/pm_domain.h>
> #include <linux/soc/qcom/llcc-qcom.h>
> +#include <linux/soc/qcom/smem.h>
>
> #define GPU_PAS_ID 13
>
> @@ -669,17 +670,22 @@ static void a6xx_calc_ubwc_config(struct adreno_gpu
> *gpu)
> static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
> {
> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
> + u32 hbb = qcom_smem_dram_get_hbb();
> + u32 ubwc_mode = adreno_gpu->ubwc_config.ubwc_swizzle & 1;
> + u32 level2_swizzling_dis = !(adreno_gpu->ubwc_config.ubwc_swizzle &
> 2);
> + u32 hbb_hi, hbb_lo;
> +
> /*
> * We subtract 13 from the highest bank bit (13 is the minimum value
> * allowed by hw) and write the lowest two bits of the remaining value
> * as hbb_lo and the one above it as hbb_hi to the hardware.
> */
> - BUG_ON(adreno_gpu->ubwc_config.highest_bank_bit < 13);
> - u32 hbb = adreno_gpu->ubwc_config.highest_bank_bit - 13;
> - u32 hbb_hi = hbb >> 2;
> - u32 hbb_lo = hbb & 3;
> - u32 ubwc_mode = adreno_gpu->ubwc_config.ubwc_swizzle & 1;
> - u32 level2_swizzling_dis = !(adreno_gpu->ubwc_config.ubwc_swizzle &
> 2);
> + if (hbb < 0)
> + hbb = adreno_gpu->ubwc_config.highest_bank_bit;
No. The value we expose to userspace must match what we program.
You'll break VK_EXT_host_image_copy otherwise.
Connor
> + hbb -= 13;
> + BUG_ON(hbb < 0);
> + hbb_hi = hbb >> 2;
> + hbb_lo = hbb & 3;
>
> gpu_write(gpu, REG_A6XX_RB_NC_MODE_CNTL,
> level2_swizzling_dis << 12 |
> @@ -2467,6 +2473,10 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
> bool is_a7xx;
> int ret;
>
> + /* We need data from SMEM to retrieve HBB in set_ubwc_config() */
> + if (!qcom_smem_is_available())
> + return ERR_PTR(-EPROBE_DEFER);
> +
> a6xx_gpu = kzalloc(sizeof(*a6xx_gpu), GFP_KERNEL);
> if (!a6xx_gpu)
> return ERR_PTR(-ENOMEM);
>
> --
> 2.49.0
>
