On 3/1/2023 2:10 AM, Konrad Dybcio wrote:
>
> On 28.02.2023 21:23, Akhil P Oommen wrote:
>> On 2/23/2023 5:36 PM, Konrad Dybcio wrote:
>>> Rename lower_bit to hbb_lo and explain what it signifies.
>>> Add explanations (wherever possible to other tunables).
>>>
>>> Sort the variable definition and assignment alphabetically.
>> Sorting based on decreasing order of line length is more readable, isn't it?
> I can do that.
>
>>> Port setting min_access_length, ubwc_mode and hbb_hi from downstream.
>>> Set default values for all of the tunables to zero, as they should be.
>>>
>>> Values were validated against downstream and will be fixed up in
>>> separate commits so as not to make this one even more messy.
>>>
>>> A618 remains untouched (left at hw defaults) in this patch.
>>>
>>> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
>>> ---
>>> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 55 ++++++++++++++++++++++++++++-------
>>> 1 file changed, 45 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>>> index c5f5d0bb3fdc..bdae341e0a7c 100644
>>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>>> @@ -786,39 +786,74 @@ static void a6xx_set_cp_protect(struct msm_gpu *gpu)
>>> static void a6xx_set_ubwc_config(struct msm_gpu *gpu)
>>> {
>>> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>> - u32 lower_bit = 2;
>>> + /* Unknown, introduced with A640/680 */
>>> u32 amsbc = 0;
>>> + /*
>>> + * The Highest Bank Bit value represents the bit of the highest DDR bank.
>>> + * We then subtract 13 from it (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. The default values (when HBB is
>>> + * not specified) are 0, 0.
>>> + */
>>> + u32 hbb_hi = 0;
>>> + u32 hbb_lo = 0;
>>> + /* Whether the minimum access length is 64 bits */
>>> + u32 min_acc_len = 0;
>>> + /* Unknown, introduced with A650 family, related to UBWC mode/ver 4 */
>>> u32 rgb565_predicator = 0;
>>> + /* Unknown, introduced with A650 family */
>>> u32 uavflagprd_inv = 0;
>>> + /* Entirely magic, per-GPU-gen value */
>>> + u32 ubwc_mode = 0;
>>>
>>> /* a618 is using the hw default values */
>>> if (adreno_is_a618(adreno_gpu))
>>> return;
>>>
>>> - if (adreno_is_a640_family(adreno_gpu))
>>> + if (adreno_is_a619(adreno_gpu)) {
>>> + /* HBB = 14 */
>>> + hbb_lo = 1;
>>> + }
>>> +
>>> + if (adreno_is_a630(adreno_gpu)) {
>>> + /* HBB = 15 */
>>> + hbb_lo = 2;
>>> + }
>>> +
>>> + if (adreno_is_a640_family(adreno_gpu)) {
>>> amsbc = 1;
>>> + /* HBB = 15 */
>>> + hbb_lo = 2;
>>> + }
>>>
>>> if (adreno_is_a650(adreno_gpu) || adreno_is_a660(adreno_gpu)) {
>>> - /* TODO: get ddr type from bootloader and use 2 for LPDDR4 */
>>> - lower_bit = 3;
>>> amsbc = 1;
>>> + /* TODO: get ddr type from bootloader and use 2 for LPDDR4 */
>>> + /* HBB = 16 */
>>> + hbb_lo = 3;
>>> rgb565_predicator = 1;
>>> uavflagprd_inv = 2;
>>> }
>>>
>>> if (adreno_is_7c3(adreno_gpu)) {
>>> - lower_bit = 1;
>>> amsbc = 1;
>>> + /* HBB is unset in downstream DTS, defaulting to 0 */
>> This is incorrect. For 7c3 hbb value is 14. So hbb_lo should be 1. FYI, hbb configurations were moved to the driver from DT in recent downstream kernels.
> Right, seems to have happened with msm-5.10. Though a random kernel I
> grabbed seems to suggest it's 15 and not 14?
>
> https://github.com/sonyxperiadev/kernel/blob/aosp/K.P.1.0.r1/drivers/gpu/msm/adreno-gpulist.h#L1710
We override that with 14 in a6xx_init() for LP4 platforms dynamically. Since 7c3 is only supported on LP4, we can hardcode 14 here.
In the downstream kernel, there is an api (of_fdt_get_ddrtype()) to detect ddrtype. If we can get something like that in upstream, we should implement a similar logic here.
-Akhil.
>
> Konrad
>> -Akhil.
>>> rgb565_predicator = 1;
>>> uavflagprd_inv = 2;
>>> }
>>>
>>> gpu_write(gpu, REG_A6XX_RB_NC_MODE_CNTL,
>>> - rgb565_predicator << 11 | amsbc << 4 | lower_bit << 1);
>>> - gpu_write(gpu, REG_A6XX_TPL1_NC_MODE_CNTL, lower_bit << 1);
>>> - gpu_write(gpu, REG_A6XX_SP_NC_MODE_CNTL,
>>> - uavflagprd_inv << 4 | lower_bit << 1);
>>> - gpu_write(gpu, REG_A6XX_UCHE_MODE_CNTL, lower_bit << 21);
>>> + rgb565_predicator << 11 | hbb_hi << 10 | amsbc << 4 |
>>> + min_acc_len << 3 | hbb_lo << 1 | ubwc_mode);
>>> +
>>> + gpu_write(gpu, REG_A6XX_TPL1_NC_MODE_CNTL, hbb_hi << 4 |
>>> + min_acc_len << 3 | hbb_lo << 1 | ubwc_mode);
>>> +
>>> + gpu_write(gpu, REG_A6XX_SP_NC_MODE_CNTL, hbb_hi << 10 |
>>> + uavflagprd_inv << 4 | min_acc_len << 3 |
>>> + hbb_lo << 1 | ubwc_mode);
>>> +
>>> + gpu_write(gpu, REG_A6XX_UCHE_MODE_CNTL, min_acc_len << 23 | hbb_lo << 21);
>>> }
>>>
>>> static int a6xx_cp_init(struct msm_gpu *gpu)
>>>
