On 15.01.2025 8:59 PM, Dmitry Baryshkov wrote:
> On Thu, Jan 16, 2025 at 01:07:17AM +0530, Akhil P Oommen wrote:
>> On 1/9/2025 7:27 PM, Konrad Dybcio wrote:
>>> On 8.01.2025 11:42 PM, Akhil P Oommen wrote:
>>>> Adreno X1-85 has an additional bit which is at a non-contiguous
>>>> location in qfprom. Add support for this new "hi" bit along with
>>>> the speedbin mappings.
>>>> ---
>>>> drivers/gpu/drm/msm/adreno/a6xx_catalog.c | 5 +++++
>>>> drivers/gpu/drm/msm/adreno/adreno_gpu.c | 15 ++++++++++++++-
>>>> 2 files changed, 19 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_catalog.c b/drivers/gpu/drm/msm/adreno/a6xx_catalog.c
>>>> index 0c560e84ad5a53bb4e8a49ba4e153ce9cf33f7ae..e2261f50aabc6a2f931d810f3637dfdba5695f43 100644
>>>> --- a/drivers/gpu/drm/msm/adreno/a6xx_catalog.c
>>>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_catalog.c
>>>> @@ -1412,6 +1412,11 @@ static const struct adreno_info a7xx_gpus[] = {
>>>> .gmu_cgc_mode = 0x00020202,
>>>> },
>>>> .address_space_size = SZ_256G,
>>>> + .speedbins = ADRENO_SPEEDBINS(
>>>> + { 0, 0 },
>>>> + { 263, 1 },
>>>> + { 315, 0 },
>>>> + ),
>>>> .preempt_record_size = 4192 * SZ_1K,
>>>> }, {
>>>> .chip_ids = ADRENO_CHIP_IDS(0x43051401), /* "C520v2" */
>>>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>> index 75f5367e73caace4648491b041f80b7c4d26bf89..7b31379eff444cf3f8ed0dcfd23c14920c13ee9d 100644
>>>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>> @@ -1078,7 +1078,20 @@ void adreno_gpu_ocmem_cleanup(struct adreno_ocmem *adreno_ocmem)
>>>>
>>>> int adreno_read_speedbin(struct device *dev, u32 *speedbin)
>>>> {
>>>> - return nvmem_cell_read_variable_le_u32(dev, "speed_bin", speedbin);
>>>> + u32 hi_bits = 0;
>>>> + int ret;
>>>> +
>>>> + ret = nvmem_cell_read_variable_le_u32(dev, "speed_bin", speedbin);
>>>> + if (ret)
>>>> + return ret;
>>>> +
>>>> + /* Some chipsets have MSB bits (BIT(8) and above) at a non-contiguous location */
>>>> + ret = nvmem_cell_read_variable_le_u32(dev, "speed_bin_hi", &hi_bits);
>>>> + if (ret != -ENOENT)
>>>> + return ret;
>>>> +
>>>> + *speedbin |= (hi_bits << 8);
>>>
>>> Now that we're overwriting speedbin, we should probably have some checks in
>>> order to make sure somebody passing a too-wide cell to one of these won't
>>> result in cripplingly-untraceable value corruption
>>>
>>> I guess we could just introduce nvmem_cell_read_variable_le_u8() and call it
>>> a day?
>>
>> X1E is an outlier here, because this was fixed from the next chipset
>> onward. For newer chipsets, we can use just the "speed_bin" node, which
>> represents a contiguous 9 bits. So, just do a "WARN_ON(fls(speedbin) >
>> 8)" here?
>
> Or extend nvmem core to support non-contiguous fields.
This sounds more desirable, as we surely aren't the only ones with
such a "feature"..
Konrad
