From 2aec2e8dba36168b1d3c84643a676777100e01ee Mon Sep 17 00:00:00 2001
From: David Rosca <david.rosca@amd.com>
Date: Thu, 28 May 2026 16:06:45 +0200
Subject: [PATCH] ac/parse_ib: Add VCN decode queue parsing

Reviewed-by: Benjamin Cheng <benjamin.cheng@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/41861>
---
 src/amd/common/ac_parse_ib.c | 97 ++++++++++++++++++++++++++++++++++--
 1 file changed, 92 insertions(+), 5 deletions(-)

diff --git a/src/amd/common/ac_parse_ib.c b/src/amd/common/ac_parse_ib.c
index fa67fd66671..ebe590191f4 100644
--- a/src/amd/common/ac_parse_ib.c
+++ b/src/amd/common/ac_parse_ib.c
@@ -1337,6 +1337,94 @@ static void print_vcn_msg_buffer_contents(FILE *f, struct ac_ib_parser *ib, uint
    }
 }
 
+static void parse_vcn_dec_ib(FILE *f, struct ac_ib_parser *ib)
+{
+   uint32_t data0;
+   uint32_t data1;
+   uint32_t data2;
+   struct ac_vcn_dec_reg reg;
+   ac_vcn_dec_init_regs(&reg, ib->vcn_version);
+
+   while (ib->cur_dw < ib->num_dw) {
+      const uint32_t dw = ac_ib_get(ib);
+      const uint32_t idx = RDECODE_PKT0_BASE_INDEX_G(dw) << 2;
+      if (dw == 0x81FF) {
+         fprintf(f, "NOP\n");
+      } else if (idx == reg.data0) {
+         fprintf(f, "VCPU_DATA0\n");
+         data0 = ac_ib_get(ib);
+         fprintf(f, "\n");
+      } else if (idx == reg.data1) {
+         fprintf(f, "VCPU_DATA1\n");
+         data1 = ac_ib_get(ib);
+         fprintf(f, "\n");
+      } else if (idx == reg.data2) {
+         fprintf(f, "VCPU_DATA2\n");
+         data2 = ac_ib_get(ib);
+         fprintf(f, "\n");
+      } else if (idx == reg.cmd) {
+         fprintf(f, "VCPU_CMD\n");
+         uint32_t cmd = ac_ib_get(ib) >> 1;
+         const char *name = NULL;
+         switch (cmd) {
+         case RDECODE_CMD_MSG_BUFFER:
+            name = "MSG BUFFER";
+            break;
+         case RDECODE_CMD_DPB_BUFFER:
+            name = "DPB BUFFER";
+            break;
+         case RDECODE_CMD_DECODING_TARGET_BUFFER:
+            name = "DECODING TARGET BUFFER";
+            break;
+         case RDECODE_CMD_FEEDBACK_BUFFER:
+            name = "FEEDBACK BUFFER";
+            break;
+         case RDECODE_CMD_PROB_TBL_BUFFER:
+            name = "PROB TBL BUFFER";
+            break;
+         case RDECODE_CMD_SESSION_CONTEXT_BUFFER:
+            name = "SESSION CONTEXT BUFFER";
+            break;
+         case RDECODE_CMD_BITSTREAM_BUFFER:
+            name = "BITSTREAM BUFFER";
+            break;
+         case RDECODE_CMD_IT_SCALING_TABLE_BUFFER:
+            name = "IT SCALING BUFFER";
+            break;
+         case RDECODE_CMD_CONTEXT_BUFFER:
+            name = "CONTEXT BUFFER";
+            break;
+         case RDECODE_CMD_SUBSAMPLE:
+            name = "SUBSAMPLE BUFFER";
+            break;
+         case RDECODE_CMD_WRITE_MEMORY:
+            name = "WRITE MEMORY";
+            break;
+         default:
+            name = "UNKNOWN";
+            break;
+         }
+         uint64_t va = ((uint64_t)data1 << 32) | data0;
+         fprintf(f, "%s%s%s VA=0x%"PRIx64, O_COLOR_GREEN, name, O_COLOR_RESET, va);
+         if (cmd == RDECODE_CMD_WRITE_MEMORY)
+            fprintf(f, " val=%u", data2);
+         fprintf(f, "\n");
+         if (cmd == RDECODE_CMD_MSG_BUFFER)
+            print_vcn_msg_buffer_contents(f, ib, va);
+      } else if (idx == reg.cntl) {
+         fprintf(f, "VCPU_CNTL\n");
+         uint32_t cntl = ac_ib_get(ib);
+         if (cntl == 1)
+            fprintf(f, "%sDECODE%s", O_COLOR_PURPLE, O_COLOR_RESET);
+         fprintf(f, "\n");
+      } else {
+         fprintf(f, "UNKNOWN\n");
+         ac_ib_get(ib);
+         fprintf(f, "\n");
+      }
+   }
+}
+
 static uint64_t print_vcn_addr(FILE *f, struct ac_ib_parser *ib, bool high_first, const char *prefix_format, ...)
 {
    uint32_t high = ac_ib_get(ib);
@@ -2424,11 +2512,10 @@ static void parse_vcn_ib(FILE *f, struct ac_ib_parser *ib)
             print_vcn_unrecognized_params(f, ib, start_dw, size);
          }
       }
-   } else {
-      if (ib->ip_type == AMD_IP_VCN_ENC) {
-         parse_vcn_enc_ib(f, ib, 0);
-         return;
-      }
+   } else if (ib->ip_type == AMD_IP_VCN_DEC) {
+      parse_vcn_dec_ib(f, ib);
+   } else if (ib->ip_type == AMD_IP_VCN_ENC) {
+      parse_vcn_enc_ib(f, ib, 0);
    }
 }