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drm/msm/a6xx: Fix excessive stack usage

Rob Clark requested to merge robclark/msm:msm-next-robclark into msm-next

Clang-19 and above sometimes end up with multiple copies of the large a6xx_hfi_msg_bw_table structure on the stack. The problem is that a6xx_hfi_send_bw_table() calls a number of device specific functions to fill the structure, but these create another copy of the structure on the stack which gets copied to the first.

If the functions get inlined, that busts the warning limit:

drivers/gpu/drm/msm/adreno/a6xx_hfi.c:631:12: error: stack frame size (1032) exceeds limit (1024) in 'a6xx_hfi_send_bw_table' [-Werror,-Wframe-larger-than]

Fix this by kmalloc-ating struct a6xx_hfi_msg_bw_table instead of using the stack. Also, use this opportunity to skip re-initializing this table to optimize gpu wake up latency.

Cc: Arnd Bergmann arnd@kernel.org Signed-off-by: Akhil P Oommen quic_akhilpo@quicinc.com Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Patchwork: https://patchwork.freedesktop.org/patch/621814/ Signed-off-by: Rob Clark robdclark@chromium.org

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