On 4/9/25 5:30 PM, Connor Abbott wrote:
> On Wed, Apr 9, 2025 at 11:22 AM Konrad Dybcio
> <konrad.dyb...@oss.qualcomm.com> wrote:
>>
>> On 4/9/25 5:12 PM, Connor Abbott wrote:
>>> 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.
>>
>> I didn't know that was exposed to userspace.
>>
>> The value must be altered either way - ultimately, the hardware must
>> receive the correct information. ubwc_config doesn't seem to be const,
>> so I can edit it there if you like it better.
>>
>> Konrad
>
> Yes, you should be calling qcom_smem_dram_get_hbb() in
> a6xx_calc_ubwc_config(). You can already see there's a TODO there to
> plug it in.
Does this look good instead?
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 0cc397378c99..ae8dbc250e6a 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -588,6 +588,8 @@ static void a6xx_set_cp_protect(struct msm_gpu *gpu)
static void a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
{
+ u8 hbb;
+
gpu->ubwc_config.rgb565_predicator = 0;
gpu->ubwc_config.uavflagprd_inv = 0;
gpu->ubwc_config.min_acc_len = 0;
@@ -636,7 +638,6 @@ static void a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
adreno_is_a690(gpu) ||
adreno_is_a730(gpu) ||
adreno_is_a740_family(gpu)) {
- /* TODO: get ddr type from bootloader and use 2 for LPDDR4 */
gpu->ubwc_config.highest_bank_bit = 16;
gpu->ubwc_config.amsbc = 1;
gpu->ubwc_config.rgb565_predicator = 1;
@@ -665,6 +666,13 @@ static void a6xx_calc_ubwc_config(struct adreno_gpu *gpu)
gpu->ubwc_config.highest_bank_bit = 14;
gpu->ubwc_config.min_acc_len = 1;
}
+
+ /* Attempt to retrieve HBB data from SMEM, keep the above defaults in
case of error */
+ hbb = qcom_smem_dram_get_hbb();
+ if (hbb < 0)
+ return;
+
+ gpu->ubwc_config.highest_bank_bit = hbb;
}
static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
Konrad
