drm/radeon/kms: Add initial support for async DMA on cayman/TN

There are 2 async DMA engines on cayman, one at 0xd000 and
one at 0xd800.  The programming interface is the same as
evergreen however there are some changes to the commands
for using vmids.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/evergreen.c

@@ -2404,6 +2404,8 @@ void evergreen_disable_interrupt_state(struct radeon_device *rdev)
 					 CNTX_BUSY_INT_ENABLE | CNTX_EMPTY_INT_ENABLE);
 		cayman_cp_int_cntl_setup(rdev, 1, 0);
 		cayman_cp_int_cntl_setup(rdev, 2, 0);
+		tmp = RREG32(CAYMAN_DMA1_CNTL) & ~TRAP_ENABLE;
+		WREG32(CAYMAN_DMA1_CNTL, tmp);
 	} else
 		WREG32(CP_INT_CNTL, CNTX_BUSY_INT_ENABLE | CNTX_EMPTY_INT_ENABLE);
 	tmp = RREG32(DMA_CNTL) & ~TRAP_ENABLE;
@@ -2460,7 +2462,7 @@ int evergreen_irq_set(struct radeon_device *rdev)
 	u32 grbm_int_cntl = 0;
 	u32 grph1 = 0, grph2 = 0, grph3 = 0, grph4 = 0, grph5 = 0, grph6 = 0;
 	u32 afmt1 = 0, afmt2 = 0, afmt3 = 0, afmt4 = 0, afmt5 = 0, afmt6 = 0;
-	u32 dma_cntl;
+	u32 dma_cntl, dma_cntl1 = 0;
 
 	if (!rdev->irq.installed) {
 		WARN(1, "Can't enable IRQ/MSI because no handler is installed\n");
@@ -2517,6 +2519,14 @@ int evergreen_irq_set(struct radeon_device *rdev)
 		dma_cntl |= TRAP_ENABLE;
 	}
 
+	if (rdev->family >= CHIP_CAYMAN) {
+		dma_cntl1 = RREG32(CAYMAN_DMA1_CNTL) & ~TRAP_ENABLE;
+		if (atomic_read(&rdev->irq.ring_int[CAYMAN_RING_TYPE_DMA1_INDEX])) {
+			DRM_DEBUG("r600_irq_set: sw int dma1\n");
+			dma_cntl1 |= TRAP_ENABLE;
+		}
+	}
+
 	if (rdev->irq.crtc_vblank_int[0] ||
 	    atomic_read(&rdev->irq.pflip[0])) {
 		DRM_DEBUG("evergreen_irq_set: vblank 0\n");
@@ -2605,6 +2615,9 @@ int evergreen_irq_set(struct radeon_device *rdev)
 
 	WREG32(DMA_CNTL, dma_cntl);
 
+	if (rdev->family >= CHIP_CAYMAN)
+		WREG32(CAYMAN_DMA1_CNTL, dma_cntl1);
+
 	WREG32(GRBM_INT_CNTL, grbm_int_cntl);
 
 	WREG32(INT_MASK + EVERGREEN_CRTC0_REGISTER_OFFSET, crtc1);
@@ -3147,6 +3160,12 @@ int evergreen_irq_process(struct radeon_device *rdev)
 		case 233: /* GUI IDLE */
 			DRM_DEBUG("IH: GUI idle\n");
 			break;
+		case 244: /* DMA trap event */
+			if (rdev->family >= CHIP_CAYMAN) {
+				DRM_DEBUG("IH: DMA1 trap\n");
+				radeon_fence_process(rdev, CAYMAN_RING_TYPE_DMA1_INDEX);
+			}
+			break;
 		default:
 			DRM_DEBUG("Unhandled interrupt: %d %d\n", src_id, src_data);
 			break;

drivers/gpu/drm/radeon/evergreend.h

@@ -918,6 +918,8 @@
 #       define CTXEMPTY_INT_ENABLE                        (1 << 28)
 #define DMA_TILING_CONFIG  				  0xD0B8
 
+#define CAYMAN_DMA1_CNTL                                  0xd82c
+
 /* async DMA packets */
 #define DMA_PACKET(cmd, t, s, n)	((((cmd) & 0xF) << 28) |	\
 					 (((t) & 0x1) << 23) |		\