drm/radeon/kms: fix evergreen asic reset

Only reset the grbm blocks, srbm tends to lock the GPU
if not done properly and in most cases is not necessary.
Also, no need to call asic init after reset the grbm blocks.

Signed-off-by: Alex Deucher <[e-mail]>
Cc: [e-mail]
Reviewed-by: Jerome Glisse <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>

drivers/gpu/drm/radeon/evergreen.c

···
 static int evergreen_gpu_soft_reset(struct radeon_device *rdev)
 {
 	struct evergreen_mc_save save;
-	u32 srbm_reset = 0;
 	u32 grbm_reset = 0;
 
 	dev_info(rdev->dev, "GPU softreset \n");
···
 	udelay(50);
 	WREG32(GRBM_SOFT_RESET, 0);
 	(void)RREG32(GRBM_SOFT_RESET);
-
-	/* reset all the system blocks */
-	srbm_reset = SRBM_SOFT_RESET_ALL_MASK;
-
-	dev_info(rdev->dev, "  SRBM_SOFT_RESET=0x%08X\n", srbm_reset);
-	WREG32(SRBM_SOFT_RESET, srbm_reset);
-	(void)RREG32(SRBM_SOFT_RESET);
-	udelay(50);
-	WREG32(SRBM_SOFT_RESET, 0);
-	(void)RREG32(SRBM_SOFT_RESET);
 	/* Wait a little for things to settle down */
 	udelay(50);
 	dev_info(rdev->dev, "  GRBM_STATUS=0x%08X\n",
···
 		RREG32(GRBM_STATUS_SE1));
 	dev_info(rdev->dev, "  SRBM_STATUS=0x%08X\n",
 		RREG32(SRBM_STATUS));
-	/* After reset we need to reinit the asic as GPU often endup in an
-	 * incoherent state.
-	 */
-	atom_asic_init(rdev->mode_info.atom_context);
 	evergreen_mc_resume(rdev, &save);
 	return 0;
 }