drm/amdgpu: Add software ring callbacks for gfx9 (v8)

Set ring functions with software ring callbacks on gfx9.

The software ring could be tested by debugfs_test_ib case.

v2: Set sw_ring 2 to enable software ring by default.
v3: Remove the parameter for software ring enablement.
v4: Use amdgpu_ring_init/fini for software rings.
v5: Update for code format. Fix conflict.
v6: Remove unnecessary checks and enable software ring on gfx9 by default.
v7: Use static array for software ring names and priorities.
v8: Stop creating software rings if no gfx ring existed.

Cc: Christian Koenig <[e-mail]>
Cc: Luben Tuikov <[e-mail]>
Cc: Andrey Grodzovsky <[e-mail]>
Cc: Michel Dänzer <[e-mail]>
Cc: Likun Gao <[e-mail]>
Signed-off-by: Jiadong.Zhu <[e-mail]>
Acked-by: Luben Tuikov <[e-mail]>
Acked-by: Huang Rui <[e-mail]>
Acked-by: Christian König <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.h

···
 
 	bool				is_poweron;
 
+	struct amdgpu_ring		sw_gfx_ring[AMDGPU_MAX_SW_GFX_RINGS];
 	struct amdgpu_ring_mux          muxer;
 };
 

drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h

···
 #define AMDGPU_MAX_RINGS		28
 #define AMDGPU_MAX_HWIP_RINGS		8
 #define AMDGPU_MAX_GFX_RINGS		2
+#define AMDGPU_MAX_SW_GFX_RINGS         2
 #define AMDGPU_MAX_COMPUTE_RINGS	8
 #define AMDGPU_MAX_VCE_RINGS		3
 #define AMDGPU_MAX_UVD_ENC_RINGS	2

drivers/gpu/drm/amd/amdgpu/amdgpu_ring_mux.c

···
 
 #define AMDGPU_MUX_RESUBMIT_JIFFIES_TIMEOUT (HZ / 2)
 
+static const struct ring_info {
+	unsigned int hw_pio;
+	const char *ring_name;
+} sw_ring_info[] = {
+	{ AMDGPU_RING_PRIO_DEFAULT, "gfx_low"},
+	{ AMDGPU_RING_PRIO_2, "gfx_high"},
+};
+
 int amdgpu_ring_mux_init(struct amdgpu_ring_mux *mux, struct amdgpu_ring *ring,
 			 unsigned int entry_size)
 {
···
 void amdgpu_sw_ring_insert_nop(struct amdgpu_ring *ring, uint32_t count)
 {
 	WARN_ON(!ring->is_sw_ring);
+}
+
+const char *amdgpu_sw_ring_name(int idx)
+{
+	return idx < ARRAY_SIZE(sw_ring_info) ?
+		sw_ring_info[idx].ring_name : NULL;
+}
+
+unsigned int amdgpu_sw_ring_priority(int idx)
+{
+	return idx < ARRAY_SIZE(sw_ring_info) ?
+		sw_ring_info[idx].hw_pio : AMDGPU_RING_PRIO_DEFAULT;
 }

drivers/gpu/drm/amd/amdgpu/amdgpu_ring_mux.h

···
 void amdgpu_sw_ring_ib_begin(struct amdgpu_ring *ring);
 void amdgpu_sw_ring_ib_end(struct amdgpu_ring *ring);
 
+const char *amdgpu_sw_ring_name(int idx);
+unsigned int amdgpu_sw_ring_priority(int idx);
 #endif

drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c

···
 
 #include "amdgpu_ras.h"
 
+#include "amdgpu_ring_mux.h"
 #include "gfx_v9_4.h"
 #include "gfx_v9_0.h"
 #include "gfx_v9_4_2.h"
···
 #include "asic_reg/gc/gc_9_0_default.h"
 
 #define GFX9_NUM_GFX_RINGS     1
+#define GFX9_NUM_SW_GFX_RINGS  2
 #define GFX9_MEC_HPD_SIZE 4096
 #define RLCG_UCODE_LOADING_START_ADDRESS 0x00002000L
 #define RLC_SAVE_RESTORE_ADDR_STARTING_OFFSET 0x00000000L
···
 	struct amdgpu_ring *ring;
 	struct amdgpu_kiq *kiq;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+	unsigned int hw_prio;
 
 	switch (adev->ip_versions[GC_HWIP][0]) {
 	case IP_VERSION(9, 0, 1):
···
 			sprintf(ring->name, "gfx_%d", i);
 		ring->use_doorbell = true;
 		ring->doorbell_index = adev->doorbell_index.gfx_ring0 << 1;
+
+		/* disable scheduler on the real ring */
+		ring->no_scheduler = true;
 		r = amdgpu_ring_init(adev, ring, 1024, &adev->gfx.eop_irq,
 				     AMDGPU_CP_IRQ_GFX_ME0_PIPE0_EOP,
 				     AMDGPU_RING_PRIO_DEFAULT, NULL);
 		if (r)
 			return r;
+	}
+
+	/* set up the software rings */
+	if (adev->gfx.num_gfx_rings) {
+		for (i = 0; i < GFX9_NUM_SW_GFX_RINGS; i++) {
+			ring = &adev->gfx.sw_gfx_ring[i];
+			ring->ring_obj = NULL;
+			sprintf(ring->name, amdgpu_sw_ring_name(i));
+			ring->use_doorbell = true;
+			ring->doorbell_index = adev->doorbell_index.gfx_ring0 << 1;
+			ring->is_sw_ring = true;
+			hw_prio = amdgpu_sw_ring_priority(i);
+			r = amdgpu_ring_init(adev, ring, 1024, &adev->gfx.eop_irq,
+					     AMDGPU_CP_IRQ_GFX_ME0_PIPE0_EOP, hw_prio,
+					     NULL);
+			if (r)
+				return r;
+			ring->wptr = 0;
+		}
+
+		/* init the muxer and add software rings */
+		r = amdgpu_ring_mux_init(&adev->gfx.muxer, &adev->gfx.gfx_ring[0],
+					 GFX9_NUM_SW_GFX_RINGS);
+		if (r) {
+			DRM_ERROR("amdgpu_ring_mux_init failed(%d)\n", r);
+			return r;
+		}
+		for (i = 0; i < GFX9_NUM_SW_GFX_RINGS; i++) {
+			r = amdgpu_ring_mux_add_sw_ring(&adev->gfx.muxer,
+							&adev->gfx.sw_gfx_ring[i]);
+			if (r) {
+				DRM_ERROR("amdgpu_ring_mux_add_sw_ring failed(%d)\n", r);
+				return r;
+			}
+		}
 	}
 
 	/* set up the compute queues - allocate horizontally across pipes */
···
 {
 	int i;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+
+	if (adev->gfx.num_gfx_rings) {
+		for (i = 0; i < GFX9_NUM_SW_GFX_RINGS; i++)
+			amdgpu_ring_fini(&adev->gfx.sw_gfx_ring[i]);
+		amdgpu_ring_mux_fini(&adev->gfx.muxer);
+	}
 
 	for (i = 0; i < adev->gfx.num_gfx_rings; i++)
 		amdgpu_ring_fini(&adev->gfx.gfx_ring[i]);
···
 
 	switch (me_id) {
 	case 0:
-		amdgpu_fence_process(&adev->gfx.gfx_ring[0]);
+		/* Fence signals are handled on the software rings*/
+		if (adev->gfx.num_gfx_rings) {
+			for (i = 0; i < GFX9_NUM_SW_GFX_RINGS; i++)
+				amdgpu_fence_process(&adev->gfx.sw_gfx_ring[i]);
+		}
 		break;
 	case 1:
 	case 2:
···
 	.emit_mem_sync = gfx_v9_0_emit_mem_sync,
 };
 
+static const struct amdgpu_ring_funcs gfx_v9_0_sw_ring_funcs_gfx = {
+	.type = AMDGPU_RING_TYPE_GFX,
+	.align_mask = 0xff,
+	.nop = PACKET3(PACKET3_NOP, 0x3FFF),
+	.support_64bit_ptrs = true,
+	.secure_submission_supported = true,
+	.vmhub = AMDGPU_GFXHUB_0,
+	.get_rptr = amdgpu_sw_ring_get_rptr_gfx,
+	.get_wptr = amdgpu_sw_ring_get_wptr_gfx,
+	.set_wptr = amdgpu_sw_ring_set_wptr_gfx,
+	.emit_frame_size = /* totally 242 maximum if 16 IBs */
+		5 +  /* COND_EXEC */
+		7 +  /* PIPELINE_SYNC */
+		SOC15_FLUSH_GPU_TLB_NUM_WREG * 5 +
+		SOC15_FLUSH_GPU_TLB_NUM_REG_WAIT * 7 +
+		2 + /* VM_FLUSH */
+		8 +  /* FENCE for VM_FLUSH */
+		20 + /* GDS switch */
+		4 + /* double SWITCH_BUFFER,
+		     * the first COND_EXEC jump to the place just
+		     * prior to this double SWITCH_BUFFER
+		     */
+		5 + /* COND_EXEC */
+		7 +	 /*	HDP_flush */
+		4 +	 /*	VGT_flush */
+		14 + /*	CE_META */
+		31 + /*	DE_META */
+		3 + /* CNTX_CTRL */
+		5 + /* HDP_INVL */
+		8 + 8 + /* FENCE x2 */
+		2 + /* SWITCH_BUFFER */
+		7, /* gfx_v9_0_emit_mem_sync */
+	.emit_ib_size =	4, /* gfx_v9_0_ring_emit_ib_gfx */
+	.emit_ib = gfx_v9_0_ring_emit_ib_gfx,
+	.emit_fence = gfx_v9_0_ring_emit_fence,
+	.emit_pipeline_sync = gfx_v9_0_ring_emit_pipeline_sync,
+	.emit_vm_flush = gfx_v9_0_ring_emit_vm_flush,
+	.emit_gds_switch = gfx_v9_0_ring_emit_gds_switch,
+	.emit_hdp_flush = gfx_v9_0_ring_emit_hdp_flush,
+	.test_ring = gfx_v9_0_ring_test_ring,
+	.test_ib = gfx_v9_0_ring_test_ib,
+	.insert_nop = amdgpu_sw_ring_insert_nop,
+	.pad_ib = amdgpu_ring_generic_pad_ib,
+	.emit_switch_buffer = gfx_v9_ring_emit_sb,
+	.emit_cntxcntl = gfx_v9_ring_emit_cntxcntl,
+	.init_cond_exec = gfx_v9_0_ring_emit_init_cond_exec,
+	.patch_cond_exec = gfx_v9_0_ring_emit_patch_cond_exec,
+	.emit_frame_cntl = gfx_v9_0_ring_emit_frame_cntl,
+	.emit_wreg = gfx_v9_0_ring_emit_wreg,
+	.emit_reg_wait = gfx_v9_0_ring_emit_reg_wait,
+	.emit_reg_write_reg_wait = gfx_v9_0_ring_emit_reg_write_reg_wait,
+	.soft_recovery = gfx_v9_0_ring_soft_recovery,
+	.emit_mem_sync = gfx_v9_0_emit_mem_sync,
+};
+
 static const struct amdgpu_ring_funcs gfx_v9_0_ring_funcs_compute = {
 	.type = AMDGPU_RING_TYPE_COMPUTE,
 	.align_mask = 0xff,
···
 
 	for (i = 0; i < adev->gfx.num_gfx_rings; i++)
 		adev->gfx.gfx_ring[i].funcs = &gfx_v9_0_ring_funcs_gfx;
+
+	if (adev->gfx.num_gfx_rings) {
+		for (i = 0; i < GFX9_NUM_SW_GFX_RINGS; i++)
+			adev->gfx.sw_gfx_ring[i].funcs = &gfx_v9_0_sw_ring_funcs_gfx;
+	}
 
 	for (i = 0; i < adev->gfx.num_compute_rings; i++)
 		adev->gfx.compute_ring[i].funcs = &gfx_v9_0_ring_funcs_compute;