From 532e2c87d428d2dc18152f004c59be15281310bc Mon Sep 17 00:00:00 2001 From: Lancelot Six Date: Fri, 16 Jan 2026 14:30:27 -0600 Subject: [PATCH] drm/amdkfd: Do not include VGPR MSBs in saved PC during save The current trap handler uses the top bits of ttmp1 to store a copy of sq_wave_mode.*vgpr_msb (except for src2_vgpr_msb). This is so the effective values in sq_wave_mode can be cleared to ensure correct behavior of the trap handler. When saving sq_wave_mode, the trap handler correctly rebuilds the expected value (with *vgpr_msb restored), so the save area is correct. However, the PC itself is copied from ttmp[0:1], which contains the wave's PC as well as the saved MSBs. The debugger reads the PC from the save area and is confused when non-0 values from VGPR_MSBs are present. This patch fixes this by saving the PC in the save area's PC slot, not the composite of the PC and VGPR_MSBs. On restore, the VGPR_MSBs are restored from sq_wave_mode. Signed-off-by: Lancelot Six Tested-by: Alexey Kondratiev Reviewed-by: Jay Cornwall Cc: Vladimir Indic Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler.h | 6 +++--- drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler_gfx12.asm | 2 +- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler.h b/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler.h index 9bb7fb6a83ed..39bdc98b8b6d 100644 --- a/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler.h +++ b/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler.h @@ -3760,8 +3760,8 @@ static const uint32_t cwsr_trap_gfx12_hex[] = { 0xb8faf804, 0x8b7a847a, 0x91788478, 0x8c787a78, 0xd7610002, 0x0000fa6c, - 0x807d817d, 0x917aff6d, - 0x80000000, 0xd7610002, + 0x807d817d, 0x8b7aff6d, + 0x0000ffff, 0xd7610002, 0x0000fa7a, 0x807d817d, 0xd7610002, 0x0000fa6e, 0x807d817d, 0xd7610002, @@ -4848,7 +4848,7 @@ static const uint32_t cwsr_trap_gfx12_1_0_hex[] = { 0x9178ff78, 0x0001000c, 0x8c787a78, 0xd7610002, 0x0000fa6c, 0x807d817d, - 0x917aff6d, 0x80000000, + 0x8b7aff6d, 0x01ffffff, 0xd7610002, 0x0000fa7a, 0x807d817d, 0xd7610002, 0x0000fa6e, 0x807d817d, diff --git a/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler_gfx12.asm b/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler_gfx12.asm index c25f16e66a27..b1b1d15bb1e7 100644 --- a/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler_gfx12.asm +++ b/drivers/gpu/drm/amd/amdkfd/cwsr_trap_handler_gfx12.asm @@ -547,7 +547,7 @@ L_SAVE_HWREG: s_or_b32 s_save_state_priv, s_save_state_priv, s_save_tmp write_hwreg_to_v2(s_save_pc_lo) - s_andn2_b32 s_save_tmp, s_save_pc_hi, S_SAVE_PC_HI_FIRST_WAVE_MASK + s_and_b32 s_save_tmp, s_save_pc_hi, ADDRESS_HI32_MASK write_hwreg_to_v2(s_save_tmp) write_hwreg_to_v2(s_save_exec_lo) #if WAVE32_ONLY -- 2.47.3