Re: [Freedreno] [PATCH v8 10/18] drm/msm/a6xx: Introduce GMU wrapper support

From: Konrad Dybcio
Date: Mon Jun 19 2023 - 09:11:00 EST


On 17.06.2023 18:07, Akhil P Oommen wrote:
> On Sat, Jun 17, 2023 at 02:00:50AM +0200, Konrad Dybcio wrote:
>>
>> On 16.06.2023 19:54, Akhil P Oommen wrote:
>>> On Thu, Jun 15, 2023 at 11:43:04PM +0200, Konrad Dybcio wrote:
>>>>
>>>> On 10.06.2023 00:06, Akhil P Oommen wrote:
>>>>> On Mon, May 29, 2023 at 03:52:29PM +0200, Konrad Dybcio wrote:
>>>>>>
>>>>>> Some (particularly SMD_RPM, a.k.a non-RPMh) SoCs implement A6XX GPUs
>>>>>> but don't implement the associated GMUs. This is due to the fact that
>>>>>> the GMU directly pokes at RPMh. Sadly, this means we have to take care
>>>>>> of enabling & scaling power rails, clocks and bandwidth ourselves.
>>>>>>
>>>>>> Reuse existing Adreno-common code and modify the deeply-GMU-infused
>>>>>> A6XX code to facilitate these GPUs. This involves if-ing out lots
>>>>>> of GMU callbacks and introducing a new type of GMU - GMU wrapper (it's
>>>>>> the actual name that Qualcomm uses in their downstream kernels).
>>>>>>
>>>>>> This is essentially a register region which is convenient to model
>>>>>> as a device. We'll use it for managing the GDSCs. The register
>>>>>> layout matches the actual GMU_CX/GX regions on the "real GMU" devices
>>>>>> and lets us reuse quite a bit of gmu_read/write/rmw calls.
>>>>>>
>>>>>> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
>>>>>> ---
>> [...]
>>
>>>>>> +
>>>>>> + ret = clk_bulk_prepare_enable(gpu->nr_clocks, gpu->grp_clks);
>>>>>> + if (ret)
>>>>>> + goto err_bulk_clk;
>>>>>> +
>>>>>> + /* If anything goes south, tear the GPU down piece by piece.. */
>>>>>> + if (ret) {
>>>>>> +err_bulk_clk:
>>>>>
>>>>> Goto jump directly to another block looks odd to me. Why do you need this label
>>>>> anyway?
>>>> If clk_bulk_prepare_enable() fails, trying to proceed will hang the
>>>> platform with unclocked accesses. We need to unwind everything that
>>>> has been done up until that point, in reverse order.
>>>
>>> I missed this response from you earlier.
>>>
>>> But you are checking for 'ret' twice here. You will end up here even
>>> if you don't jump! So "if (ret) goto err_bulk_clk;" looks
>>> unnecessary.
>>>
>>> -Akhil.
>> Ohhh right, silly mistake on my part ;)
>>
>> I already sent out a v9 since.. Please check it out and if you
>> have any further comments, I'll fix this, and if not.. Perhaps I
>> could fix it in an incremental patch if that revision is gtg?
>
> Incremental patch is fine as there is no functional issue.
Okay so I took another look with today's next that already contains
this series, and it currently looks like:


ret = clk_bulk_prepare_enable(gpu->nr_clocks, gpu->grp_clks);
if (ret)
goto err_bulk_clk;

if (adreno_is_a619_holi(adreno_gpu))
a6xx_sptprac_enable(gmu);

/* If anything goes south, tear the GPU down piece by piece.. */
if (ret) {
err_bulk_clk:


So it makes sense this way.. perhaps I just left it in this patch
by mistake when I was rebasing some changes. I guess it requires
no further action now?

Konrad
>
> -Akhil.
>
>>
>> Konrad
>>>
>>>>
>>>>>
>>>>>> + pm_runtime_put(gmu->gxpd);
>>>>>> + pm_runtime_put(gmu->dev);
>>>>>> + dev_pm_opp_set_opp(&gpu->pdev->dev, NULL);
>>>>>> + }
>>>>>> +err_set_opp:
>>>>>
>>>>> Generally, it is better to name the label based on what you do here. For
>>>>> eg: "unlock_lock:".
>>>> That seems to be a mixed bag all throughout the kernel, I've seen many
>>>> usages of err_(what went wrong)
>>>>
>>>>>
>>>>> Also, this function is small enough that it is better to return directly
>>>>> in case of error. I think that would be more readable.
>>>> Not really, adding the necessary cleanup steps in `if (ret)`
>>>> blocks would roughly double the function's size.
>>>>
>>>>>
>>>>>> + mutex_unlock(&a6xx_gpu->gmu.lock);
>>>>>> +
>>>>>> + if (!ret)
>>>>>> + msm_devfreq_resume(gpu);
>>>>>> +
>>>>>> + return ret;
>>>>>> +}
>>>>>> +
>>>>>> +static int a6xx_gmu_pm_suspend(struct msm_gpu *gpu)
>>>>>> {
>>>>>> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>>>>> struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
>>>>>> @@ -1720,7 +1799,40 @@ static int a6xx_pm_suspend(struct msm_gpu *gpu)
>>>>>> return 0;
>>>>>> }
>>>>>>
>>>>>> -static int a6xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
>>>>>> +static int a6xx_pm_suspend(struct msm_gpu *gpu)
>>>>>> +{
>>>>>> + struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>>>>> + struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
>>>>>> + struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
>>>>>> + int i;
>>>>>> +
>>>>>> + trace_msm_gpu_suspend(0);
>>>>>> +
>>>>>> + msm_devfreq_suspend(gpu);
>>>>>> +
>>>>>> + mutex_lock(&a6xx_gpu->gmu.lock);
>>>>>
>>>>> Again, is this initialized somewhere?
>>>>>
>>>>>> +
>>>>>> + /* Drain the outstanding traffic on memory buses */
>>>>>> + a6xx_bus_clear_pending_transactions(adreno_gpu, true);
>>>>>> +
>>>>>> + clk_bulk_disable_unprepare(gpu->nr_clocks, gpu->grp_clks);
>>>>>> +
>>>>>> + pm_runtime_put_sync(gmu->gxpd);
>>>>>> + dev_pm_opp_set_opp(&gpu->pdev->dev, NULL);
>>>>>> + pm_runtime_put_sync(gmu->dev);
>>>>>> +
>>>>>> + mutex_unlock(&a6xx_gpu->gmu.lock);
>>>>>> +
>>>>>> + if (a6xx_gpu->shadow_bo)
>>>>>> + for (i = 0; i < gpu->nr_rings; i++)
>>>>>> + a6xx_gpu->shadow[i] = 0;
>>>>>> +
>>>>>> + gpu->suspend_count++;
>>>>>> +
>>>>>> + return 0;
>>>>>> +}
>>>>>> +
>>>>>> +static int a6xx_gmu_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
>>>>>> {
>>>>>> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>>>>> struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
>>>>>> @@ -1739,6 +1851,12 @@ static int a6xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
>>>>>> return 0;
>>>>>> }
>>>>>>
>>>>>> +static int a6xx_get_timestamp(struct msm_gpu *gpu, uint64_t *value)
>>>>>> +{
>>>>>> + *value = gpu_read64(gpu, REG_A6XX_CP_ALWAYS_ON_COUNTER);
>>>>>> + return 0;
>>>>>> +}
>>>>>> +
>>>>>> static struct msm_ringbuffer *a6xx_active_ring(struct msm_gpu *gpu)
>>>>>> {
>>>>>> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>>>>> @@ -2004,8 +2122,8 @@ static const struct adreno_gpu_funcs funcs = {
>>>>>> .set_param = adreno_set_param,
>>>>>> .hw_init = a6xx_hw_init,
>>>>>> .ucode_load = a6xx_ucode_load,
>>>>>> - .pm_suspend = a6xx_pm_suspend,
>>>>>> - .pm_resume = a6xx_pm_resume,
>>>>>> + .pm_suspend = a6xx_gmu_pm_suspend,
>>>>>> + .pm_resume = a6xx_gmu_pm_resume,
>>>>>> .recover = a6xx_recover,
>>>>>> .submit = a6xx_submit,
>>>>>> .active_ring = a6xx_active_ring,
>>>>>> @@ -2020,6 +2138,35 @@ static const struct adreno_gpu_funcs funcs = {
>>>>>> #if defined(CONFIG_DRM_MSM_GPU_STATE)
>>>>>> .gpu_state_get = a6xx_gpu_state_get,
>>>>>> .gpu_state_put = a6xx_gpu_state_put,
>>>>>> +#endif
>>>>>> + .create_address_space = a6xx_create_address_space,
>>>>>> + .create_private_address_space = a6xx_create_private_address_space,
>>>>>> + .get_rptr = a6xx_get_rptr,
>>>>>> + .progress = a6xx_progress,
>>>>>> + },
>>>>>> + .get_timestamp = a6xx_gmu_get_timestamp,
>>>>>> +};
>>>>>> +
>>>>>> +static const struct adreno_gpu_funcs funcs_gmuwrapper = {
>>>>>> + .base = {
>>>>>> + .get_param = adreno_get_param,
>>>>>> + .set_param = adreno_set_param,
>>>>>> + .hw_init = a6xx_hw_init,
>>>>>> + .ucode_load = a6xx_ucode_load,
>>>>>> + .pm_suspend = a6xx_pm_suspend,
>>>>>> + .pm_resume = a6xx_pm_resume,
>>>>>> + .recover = a6xx_recover,
>>>>>> + .submit = a6xx_submit,
>>>>>> + .active_ring = a6xx_active_ring,
>>>>>> + .irq = a6xx_irq,
>>>>>> + .destroy = a6xx_destroy,
>>>>>> +#if defined(CONFIG_DRM_MSM_GPU_STATE)
>>>>>> + .show = a6xx_show,
>>>>>> +#endif
>>>>>> + .gpu_busy = a6xx_gpu_busy,
>>>>>> +#if defined(CONFIG_DRM_MSM_GPU_STATE)
>>>>>> + .gpu_state_get = a6xx_gpu_state_get,
>>>>>> + .gpu_state_put = a6xx_gpu_state_put,
>>>>>> #endif
>>>>>> .create_address_space = a6xx_create_address_space,
>>>>>> .create_private_address_space = a6xx_create_private_address_space,
>>>>>> @@ -2050,15 +2197,31 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
>>>>>>
>>>>>> adreno_gpu->registers = NULL;
>>>>>>
>>>>>> + /* Check if there is a GMU phandle and set it up */
>>>>>> + node = of_parse_phandle(pdev->dev.of_node, "qcom,gmu", 0);
>>>>>> + /* FIXME: How do we gracefully handle this? */
>>>>>> + BUG_ON(!node);
>>>>>> +
>>>>>> + adreno_gpu->gmu_is_wrapper = of_device_is_compatible(node, "qcom,adreno-gmu-wrapper");
>>>>>> +
>>>>>> /*
>>>>>> * We need to know the platform type before calling into adreno_gpu_init
>>>>>> * so that the hw_apriv flag can be correctly set. Snoop into the info
>>>>>> * and grab the revision number
>>>>>> */
>>>>>> info = adreno_info(config->rev);
>>>>>> -
>>>>>> - if (info && (info->revn == 650 || info->revn == 660 ||
>>>>>> - adreno_cmp_rev(ADRENO_REV(6, 3, 5, ANY_ID), info->rev)))
>>>>>> + if (!info)
>>>>>> + return ERR_PTR(-EINVAL);
>>>>>> +
>>>>>> + /* Assign these early so that we can use the is_aXYZ helpers */
>>>>>> + /* Numeric revision IDs (e.g. 630) */
>>>>>> + adreno_gpu->revn = info->revn;
>>>>>> + /* New-style ADRENO_REV()-only */
>>>>>> + adreno_gpu->rev = info->rev;
>>>>>> + /* Quirk data */
>>>>>> + adreno_gpu->info = info;
>>>>>> +
>>>>>> + if (adreno_is_a650(adreno_gpu) || adreno_is_a660_family(adreno_gpu))
>>>>>> adreno_gpu->base.hw_apriv = true;
>>>>>>
>>>>>> a6xx_llc_slices_init(pdev, a6xx_gpu);
>>>>>> @@ -2069,7 +2232,10 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
>>>>>> return ERR_PTR(ret);
>>>>>> }
>>>>>>
>>>>>> - ret = adreno_gpu_init(dev, pdev, adreno_gpu, &funcs, 1);
>>>>>> + if (adreno_has_gmu_wrapper(adreno_gpu))
>>>>>> + ret = adreno_gpu_init(dev, pdev, adreno_gpu, &funcs_gmuwrapper, 1);
>>>>>> + else
>>>>>> + ret = adreno_gpu_init(dev, pdev, adreno_gpu, &funcs, 1);
>>>>>> if (ret) {
>>>>>> a6xx_destroy(&(a6xx_gpu->base.base));
>>>>>> return ERR_PTR(ret);
>>>>>> @@ -2082,13 +2248,10 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
>>>>>> if (adreno_is_a618(adreno_gpu) || adreno_is_7c3(adreno_gpu))
>>>>>> priv->gpu_clamp_to_idle = true;
>>>>>>
>>>>>> - /* Check if there is a GMU phandle and set it up */
>>>>>> - node = of_parse_phandle(pdev->dev.of_node, "qcom,gmu", 0);
>>>>>> -
>>>>>> - /* FIXME: How do we gracefully handle this? */
>>>>>> - BUG_ON(!node);
>>>>>> -
>>>>>> - ret = a6xx_gmu_init(a6xx_gpu, node);
>>>>>> + if (adreno_has_gmu_wrapper(adreno_gpu))
>>>>>> + ret = a6xx_gmu_wrapper_init(a6xx_gpu, node);
>>>>>> + else
>>>>>> + ret = a6xx_gmu_init(a6xx_gpu, node);
>>>>>> of_node_put(node);
>>>>>> if (ret) {
>>>>>> a6xx_destroy(&(a6xx_gpu->base.base));
>>>>>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>>>>>> index aa70390ee1c6..c788b06e72da 100644
>>>>>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>>>>>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
>>>>>> @@ -76,6 +76,7 @@ int a6xx_gmu_set_oob(struct a6xx_gmu *gmu, enum a6xx_gmu_oob_state state);
>>>>>> void a6xx_gmu_clear_oob(struct a6xx_gmu *gmu, enum a6xx_gmu_oob_state state);
>>>>>>
>>>>>> int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
>>>>>> +int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
>>>>>> void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu);
>>>>>>
>>>>>> void a6xx_gmu_set_freq(struct msm_gpu *gpu, struct dev_pm_opp *opp,
>>>>>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
>>>>>> index 30ecdff363e7..4e5d650578c6 100644
>>>>>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
>>>>>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
>>>>>> @@ -1041,16 +1041,18 @@ struct msm_gpu_state *a6xx_gpu_state_get(struct msm_gpu *gpu)
>>>>>> /* Get the generic state from the adreno core */
>>>>>> adreno_gpu_state_get(gpu, &a6xx_state->base);
>>>>>>
>>>>>> - a6xx_get_gmu_registers(gpu, a6xx_state);
>>>>>> + if (!adreno_has_gmu_wrapper(adreno_gpu)) {
>>>>>> + a6xx_get_gmu_registers(gpu, a6xx_state);
>>>>>>
>>>>>> - a6xx_state->gmu_log = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.log);
>>>>>> - a6xx_state->gmu_hfi = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.hfi);
>>>>>> - a6xx_state->gmu_debug = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.debug);
>>>>>> + a6xx_state->gmu_log = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.log);
>>>>>> + a6xx_state->gmu_hfi = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.hfi);
>>>>>> + a6xx_state->gmu_debug = a6xx_snapshot_gmu_bo(a6xx_state, &a6xx_gpu->gmu.debug);
>>>>>> /
>>>>>> - a6xx_snapshot_gmu_hfi_history(gpu, a6xx_state);
>>>>>> + a6xx_snapshot_gmu_hfi_history(gpu, a6xx_state);
>>>>>> + }
>>>>>>
>>>>>> /* If GX isn't on the rest of the data isn't going to be accessible */
>>>>>> - if (!a6xx_gmu_gx_is_on(&a6xx_gpu->gmu))
>>>>>> + if (!adreno_has_gmu_wrapper(adreno_gpu) && !a6xx_gmu_gx_is_on(&a6xx_gpu->gmu))
>>>>>> return &a6xx_state->base;
>>>>>>
>>>>>> /* Get the banks of indexed registers */
>>>>>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>>>> index 6934cee07d42..5c5901d65950 100644
>>>>>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>>>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>>>>>> @@ -528,6 +528,10 @@ int adreno_load_fw(struct adreno_gpu *adreno_gpu)
>>>>>> if (!adreno_gpu->info->fw[i])
>>>>>> continue;
>>>>>>
>>>>>> + /* Skip loading GMU firwmare with GMU Wrapper */
>>>>>> + if (adreno_has_gmu_wrapper(adreno_gpu) && i == ADRENO_FW_GMU)
>>>>>> + continue;
>>>>>> +
>>>>>> /* Skip if the firmware has already been loaded */
>>>>>> if (adreno_gpu->fw[i])
>>>>>> continue;
>>>>>> @@ -1074,8 +1078,8 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
>>>>>> u32 speedbin;
>>>>>> int ret;
>>>>>>
>>>>>> - /* Only handle the core clock when GMU is not in use */
>>>>>> - if (config->rev.core < 6) {
>>>>>> + /* Only handle the core clock when GMU is not in use (or is absent). */
>>>>>> + if (adreno_has_gmu_wrapper(adreno_gpu) || config->rev.core < 6) {
>>>>>> /*
>>>>>> * This can only be done before devm_pm_opp_of_add_table(), or
>>>>>> * dev_pm_opp_set_config() will WARN_ON()
>>>>>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>>>>>> index f62612a5c70f..ee5352bc5329 100644
>>>>>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>>>>>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>>>>>> @@ -115,6 +115,7 @@ struct adreno_gpu {
>>>>>> * code (a3xx_gpu.c) and stored in this common location.
>>>>>> */
>>>>>> const unsigned int *reg_offsets;
>>>>>> + bool gmu_is_wrapper;
>>>>>> };
>>>>>> #define to_adreno_gpu(x) container_of(x, struct adreno_gpu, base)
>>>>>>
>>>>>> @@ -145,6 +146,11 @@ struct adreno_platform_config {
>>>>>>
>>>>>> bool adreno_cmp_rev(struct adreno_rev rev1, struct adreno_rev rev2);
>>>>>>
>>>>>> +static inline bool adreno_has_gmu_wrapper(struct adreno_gpu *gpu)
>>>>>> +{
>>>>>> + return gpu->gmu_is_wrapper;
>>>>>> +}
>>>>>> +
>>>>>> static inline bool adreno_is_a2xx(struct adreno_gpu *gpu)
>>>>>> {
>>>>>> return (gpu->revn < 300);
>>>>>>
>>>>>> --
>>>>>> 2.40.1
>>>>>>
>>>>>
>>>>> I am still not fully onboard with the idea of gmu_wrapper node in devicetree.
>>>>> Aside from that, I don't see any other issue. Please check the few comments I left.
>>>> Thanks for your review!
>>>>
>>>> Konrad
>>>>>
>>>>> -Akhil.
>>>>>