drm/radeon: don't reset dma on r6xx-evergreen init

commit c1789a2e upstream.

Otherwise we may lose the DMA golden settings which can
lead to hangs, etc.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

drivers/gpu/drm/radeon/r600_dma.c

@@ -116,15 +116,6 @@ int r600_dma_resume(struct radeon_device *rdev)
 	u32 rb_bufsz;
 	int r;
 
-	/* Reset dma */
-	if (rdev->family >= CHIP_RV770)
-		WREG32(SRBM_SOFT_RESET, RV770_SOFT_RESET_DMA);
-	else
-		WREG32(SRBM_SOFT_RESET, SOFT_RESET_DMA);
-	RREG32(SRBM_SOFT_RESET);
-	udelay(50);
-	WREG32(SRBM_SOFT_RESET, 0);
-
 	WREG32(DMA_SEM_INCOMPLETE_TIMER_CNTL, 0);
 	WREG32(DMA_SEM_WAIT_FAIL_TIMER_CNTL, 0);