drivers/gpu/drm/radeon/ni_dma.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/radeon/ni_dma.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/radeon/ni_dma.c
Extension
.c
Size
13489 bytes
Lines
472
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (i == 0) {
			ring = &rdev->ring[R600_RING_TYPE_DMA_INDEX];
			reg_offset = DMA0_REGISTER_OFFSET;
			wb_offset = R600_WB_DMA_RPTR_OFFSET;
		} else {
			ring = &rdev->ring[CAYMAN_RING_TYPE_DMA1_INDEX];
			reg_offset = DMA1_REGISTER_OFFSET;
			wb_offset = CAYMAN_WB_DMA1_RPTR_OFFSET;
		}

		WREG32(DMA_SEM_INCOMPLETE_TIMER_CNTL + reg_offset, 0);
		WREG32(DMA_SEM_WAIT_FAIL_TIMER_CNTL + reg_offset, 0);

		/* Set ring buffer size in dwords */
		rb_bufsz = order_base_2(ring->ring_size / 4);
		rb_cntl = rb_bufsz << 1;
#ifdef __BIG_ENDIAN
		rb_cntl |= DMA_RB_SWAP_ENABLE | DMA_RPTR_WRITEBACK_SWAP_ENABLE;
#endif
		WREG32(DMA_RB_CNTL + reg_offset, rb_cntl);

		/* Initialize the ring buffer's read and write pointers */
		WREG32(DMA_RB_RPTR + reg_offset, 0);
		WREG32(DMA_RB_WPTR + reg_offset, 0);

		/* set the wb address whether it's enabled or not */
		WREG32(DMA_RB_RPTR_ADDR_HI + reg_offset,
		       upper_32_bits(rdev->wb.gpu_addr + wb_offset) & 0xFF);
		WREG32(DMA_RB_RPTR_ADDR_LO + reg_offset,
		       ((rdev->wb.gpu_addr + wb_offset) & 0xFFFFFFFC));

		if (rdev->wb.enabled)
			rb_cntl |= DMA_RPTR_WRITEBACK_ENABLE;

		WREG32(DMA_RB_BASE + reg_offset, ring->gpu_addr >> 8);

		/* enable DMA IBs */
		ib_cntl = DMA_IB_ENABLE | CMD_VMID_FORCE;
#ifdef __BIG_ENDIAN
		ib_cntl |= DMA_IB_SWAP_ENABLE;
#endif
		WREG32(DMA_IB_CNTL + reg_offset, ib_cntl);

		dma_cntl = RREG32(DMA_CNTL + reg_offset);
		dma_cntl &= ~CTXEMPTY_INT_ENABLE;
		WREG32(DMA_CNTL + reg_offset, dma_cntl);

		ring->wptr = 0;
		WREG32(DMA_RB_WPTR + reg_offset, ring->wptr << 2);

		WREG32(DMA_RB_CNTL + reg_offset, rb_cntl | DMA_RB_ENABLE);

		ring->ready = true;

		r = radeon_ring_test(rdev, ring->idx, ring);
		if (r) {
			ring->ready = false;
			return r;
		}
	}

	if ((rdev->asic->copy.copy_ring_index == R600_RING_TYPE_DMA_INDEX) ||
	    (rdev->asic->copy.copy_ring_index == CAYMAN_RING_TYPE_DMA1_INDEX))
		radeon_ttm_set_active_vram_size(rdev, rdev->mc.real_vram_size);

	return 0;
}

/**
 * cayman_dma_fini - tear down the async dma engines
 *
 * @rdev: radeon_device pointer
 *
 * Stop the async dma engines and free the rings (cayman-SI).
 */
void cayman_dma_fini(struct radeon_device *rdev)
{
	cayman_dma_stop(rdev);
	radeon_ring_fini(rdev, &rdev->ring[R600_RING_TYPE_DMA_INDEX]);
	radeon_ring_fini(rdev, &rdev->ring[CAYMAN_RING_TYPE_DMA1_INDEX]);
}

/**
 * cayman_dma_is_lockup - Check if the DMA engine is locked up
 *
 * @rdev: radeon_device pointer
 * @ring: radeon_ring structure holding ring information
 *
 * Check if the async DMA engine is locked up.
 * Returns true if the engine appears to be locked up, false if not.

Annotation

Implementation Notes