[PATCH 1/1] drm/msm: Expose uche trap base via uapi
Dmitry Baryshkov
dmitry.baryshkov at linaro.org
Tue Dec 3 14:43:00 UTC 2024
On Tue, Dec 03, 2024 at 03:36:08PM +0100, Danylo wrote:
>
>
>
> On 12/3/24 14:34, Dmitry Baryshkov wrote:
> > On Tue, Dec 03, 2024 at 02:09:59PM +0100, Danylo wrote:
> > >
> > >
> > > On 12/3/24 13:52, Dmitry Baryshkov wrote:
> > > > On Tue, Dec 03, 2024 at 10:59:20AM +0100, Danylo Piliaiev wrote:
> > > > > This adds MSM_PARAM_UCHE_TRAP_BASE that will be used by Mesa
> > > > > implementation for VK_KHR_shader_clock and GL_ARB_shader_clock.
> > > > Could you please spend more words, describing what it is and why is it
> > > > necessary for those extensions. For a5xx+ it looks like some kind of an
> > > > internal address (what kind of?). For a4xx I'm completely lost.
> > > Yes, my bad. On at least a6xx+, shader could read 64b ALWAYSON counter
> > > from UCHE_TRAP_BASE+0 address. We use it to implement VK_KHR_shader_clock:
> > > "This extension advertises the SPIR-V ShaderClockKHR capability for Vulkan,
> > > which
> > > allows a shader to query a real-time or monotonically incrementing counter
> > > at
> > > the subgroup level or across the device level."
> > > And there is no other proper way to get such counter. Same with
> > > GL_ARB_shader_clock.
> > Yes, please add this to the commit message.
> Ok.
>
> > > Not sure what's there on older gens, I exposed the value on them for the
> > > completeness sake. But I don't know whether it is desired or not (I don't
> > > expect
> > > the value being read and used on a4xx/a5xx in Mesa).
> > Do you know if there is anything interesting in that region on a4xx /
> > a5xx (or at least if it's a region on a4xx?) Also how will that
> > GET_PARAM behave on a2xx-a3xx? Will it return 0 or some -EINVAL?
> I don't know if there is anything interesting there on a5xx or a4xx.
> I booted a5xx board I dug up, but found out that on a5xx we are
> even missing the instruction to read from memory address, so I wasn't
> able to check what's at that address.
lol, ok.
>
> As for what to return on a2xx-a3xx, as suggested by Rob,
> I'll rebase on https://patchwork.freedesktop.org/series/141667/ then
> I will return EINVAL:
> if (adreno_gpu->uche_trap_base == 0)
> return UERR(EINVAL, drm, "no uche trap base");
Great, thanks. I think that fixes my concerns.
>
> > > > > Signed-off-by: Danylo Piliaiev <dpiliaiev at igalia.com>
> > > > > ---
> > > > > drivers/gpu/drm/msm/adreno/a4xx_gpu.c | 6 ++++--
> > > > > drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 10 ++++++----
> > > > > drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 12 +++++++-----
> > > > > drivers/gpu/drm/msm/adreno/adreno_gpu.c | 3 +++
> > > > > drivers/gpu/drm/msm/adreno/adreno_gpu.h | 2 ++
> > > > > include/uapi/drm/msm_drm.h | 1 +
> > > > > 6 files changed, 23 insertions(+), 11 deletions(-)
> > > > >
> > > > > diff --git a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
> > > > > index 50c490b492f0..f1b18a6663f7 100644
> > > > > --- a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
> > > > > +++ b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
> > > > > @@ -251,8 +251,8 @@ static int a4xx_hw_init(struct msm_gpu *gpu)
> > > > > gpu_write(gpu, REG_A4XX_UCHE_CACHE_WAYS_VFD, 0x07);
> > > > > /* Disable L2 bypass to avoid UCHE out of bounds errors */
> > > > > - gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_LO, 0xffff0000);
> > > > > - gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_HI, 0xffff0000);
> > > > > + gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
> > > > > + gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
> > > > > gpu_write(gpu, REG_A4XX_CP_DEBUG, (1 << 25) |
> > > > > (adreno_is_a420(adreno_gpu) ? (1 << 29) : 0));
> > > > > @@ -693,6 +693,8 @@ struct msm_gpu *a4xx_gpu_init(struct drm_device *dev)
> > > > > if (ret)
> > > > > goto fail;
> > > > > + adreno_gpu->uche_trap_base = 0xffff0000ffff0000ull;
> > > > > +
> > > > > if (!gpu->aspace) {
> > > > > /* TODO we think it is possible to configure the GPU to
> > > > > * restrict access to VRAM carveout. But the required
> > > > > diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > > > > index ee89db72e36e..caf2c0a7a29f 100644
> > > > > --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > > > > +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
> > > > > @@ -750,10 +750,10 @@ static int a5xx_hw_init(struct msm_gpu *gpu)
> > > > > gpu_write(gpu, REG_A5XX_UCHE_CACHE_WAYS, 0x02);
> > > > > /* Disable L2 bypass in the UCHE */
> > > > > - gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_LO, 0xFFFF0000);
> > > > > - gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_HI, 0x0001FFFF);
> > > > > - gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_LO, 0xFFFF0000);
> > > > > - gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_HI, 0x0001FFFF);
> > > > > + gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
> > > > > + gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
> > > > > + gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
> > > > > + gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
> > > > > /* Set the GMEM VA range (0 to gpu->gmem) */
> > > > > gpu_write(gpu, REG_A5XX_UCHE_GMEM_RANGE_MIN_LO, 0x00100000);
> > > > > @@ -1805,5 +1805,7 @@ struct msm_gpu *a5xx_gpu_init(struct drm_device *dev)
> > > > > adreno_gpu->ubwc_config.macrotile_mode = 0;
> > > > > adreno_gpu->ubwc_config.ubwc_swizzle = 0x7;
> > > > > + adreno_gpu->uche_trap_base = 0x0001ffffffff0000ull;
> > > > > +
> > > > > return gpu;
> > > > > }
> > > > > diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> > > > > index 019610341df1..0ae29a7c8a4d 100644
> > > > > --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> > > > > +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> > > > > @@ -1123,12 +1123,12 @@ static int hw_init(struct msm_gpu *gpu)
> > > > > /* Disable L2 bypass in the UCHE */
> > > > > if (adreno_is_a7xx(adreno_gpu)) {
> > > > > - gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, 0x0001fffffffff000llu);
> > > > > - gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, 0x0001fffffffff000llu);
> > > > > + gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, adreno_gpu->uche_trap_base);
> > > > > + gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, adreno_gpu->uche_trap_base);
> > > > > } else {
> > > > > - gpu_write64(gpu, REG_A6XX_UCHE_WRITE_RANGE_MAX, 0x0001ffffffffffc0llu);
> > > > > - gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, 0x0001fffffffff000llu);
> > > > > - gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, 0x0001fffffffff000llu);
> > > > > + gpu_write64(gpu, REG_A6XX_UCHE_WRITE_RANGE_MAX, adreno_gpu->uche_trap_base + 0xfc0);
> > > > > + gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, adreno_gpu->uche_trap_base);
> > > > > + gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, adreno_gpu->uche_trap_base);
> > > > > }
> > > > > if (!(adreno_is_a650_family(adreno_gpu) ||
> > > > > @@ -2533,6 +2533,8 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
> > > > > }
> > > > > }
> > > > > + adreno_gpu->uche_trap_base = 0x1fffffffff000ull;
> > > > > +
> > > > > if (gpu->aspace)
> > > > > msm_mmu_set_fault_handler(gpu->aspace->mmu, gpu,
> > > > > a6xx_fault_handler);
> > > > > diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> > > > > index 076be0473eb5..774ff6eacb9f 100644
> > > > > --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> > > > > +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> > > > > @@ -385,6 +385,9 @@ int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
> > > > > case MSM_PARAM_MACROTILE_MODE:
> > > > > *value = adreno_gpu->ubwc_config.macrotile_mode;
> > > > > return 0;
> > > > > + case MSM_PARAM_UCHE_TRAP_BASE:
> > > > > + *value = adreno_gpu->uche_trap_base;
> > > > > + return 0;
> > > > > default:
> > > > > DBG("%s: invalid param: %u", gpu->name, param);
> > > > > return -EINVAL;
> > > > > diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
> > > > > index e71f420f8b3a..9bd38dda4308 100644
> > > > > --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
> > > > > +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
> > > > > @@ -253,6 +253,8 @@ struct adreno_gpu {
> > > > > bool gmu_is_wrapper;
> > > > > bool has_ray_tracing;
> > > > > +
> > > > > + u64 uche_trap_base;
> > > > > };
> > > > > #define to_adreno_gpu(x) container_of(x, struct adreno_gpu, base)
> > > > > diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
> > > > > index b916aab80dde..2342cb90857e 100644
> > > > > --- a/include/uapi/drm/msm_drm.h
> > > > > +++ b/include/uapi/drm/msm_drm.h
> > > > > @@ -90,6 +90,7 @@ struct drm_msm_timespec {
> > > > > #define MSM_PARAM_RAYTRACING 0x11 /* RO */
> > > > > #define MSM_PARAM_UBWC_SWIZZLE 0x12 /* RO */
> > > > > #define MSM_PARAM_MACROTILE_MODE 0x13 /* RO */
> > > > > +#define MSM_PARAM_UCHE_TRAP_BASE 0x14 /* RO */
> > > > > /* For backwards compat. The original support for preemption was based on
> > > > > * a single ring per priority level so # of priority levels equals the #
> > > > > --
> > > > > 2.46.2
> > > > >
>
--
With best wishes
Dmitry
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