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

Otherwise we may lose the DMA golden settings which can
lead to hangs, etc.

Reviewed-by: Christian König <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>
Cc: [e-mail]

drivers/gpu/drm/radeon/r600_dma.c

···
 	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);