Disassemble rspboot microcode

2026-09-12 20:16:02 -04:00 · 2021-11-22 20:31:52 +10:00
parent a264f88479
commit bab24b7660
4 changed files with 102 additions and 3 deletions
@@ -0,0 +1,89 @@
+.rsp
+
+// OSTask placed at end of DMEM (IMEM_START - sizeof(OSTask))
+.definelabel OSTask_addr, 0xfc0
+
+// OSTask data member offsets
+OSTask_flags           equ 0x04
+OSTask_ucode           equ 0x10
+OSTask_ucode_size      equ 0x14
+OSTask_ucode_data      equ 0x18
+OSTask_ucode_data_size equ 0x1c
+
+OS_TASK_DP_WAIT        equ 0x0002
+
+// RDP Status read flags
+DPC_STATUS_DMA_BUSY    equ 0x0100
+
+.create CODE_FILE, 0x04001000
+
+    j     rdpcheck
+     addi  at, zero, OSTask_addr
+
+ucodeload:
+    lw    v0, OSTask_ucode(at)
+    addi  v1, zero, 0x0f7f
+    addi  a3, zero, 0x1080
+    mtc0  a3, SP_MEM_ADDR
+    mtc0  v0, SP_DRAM_ADDR
+    mtc0  v1, SP_RD_LEN
+
+ucodeloadloop:
+    mfc0  a0, SP_DMA_BUSY
+    bne   a0, zero, ucodeloadloop
+     nop
+    jal   checkyield
+     nop
+    jr    a3
+     mtc0  zero, SP_SEMAPHORE
+
+checkyield:
+    mfc0  t0, SP_STATUS
+    andi  t0, t0, 0x0080
+    bne   t0, zero, Yield
+     nop
+    jr    ra
+
+Yield:
+     mtc0  zero, SP_SEMAPHORE
+    ori   t0, zero, 0x5200
+    mtc0  t0, SP_STATUS
+    break
+    nop
+
+rdpcheck:
+    lw    v0, OSTask_flags(at)
+    andi  v0, v0, OS_TASK_DP_WAIT
+    beq   v0, zero, rdpwait
+     nop
+    jal   checkyield
+     nop
+    mfc0  v0, DPC_STATUS
+    andi  v0, v0, DPC_STATUS_DMA_BUSY
+    bgtz  v0, checkyield
+     nop
+
+rdpwait:
+    lw    v0, OSTask_ucode_data(at)
+    lw    v1, OSTask_ucode_data_size(at)
+    addi  v1, v1, -1
+
+DMEMLoad:
+    mfc0  s8, SP_DMA_FULL
+    bne   s8, zero, DMEMLoad
+     nop
+    mtc0  zero, SP_MEM_ADDR
+    mtc0  v0, SP_DRAM_ADDR
+    mtc0  v1, SP_RD_LEN
+
+dmaloop:
+    mfc0  a0, SP_DMA_BUSY
+    bne   a0, zero, dmaloop
+     nop
+    jal   checkyield
+     nop
+    j     ucodeload
+     nop
+    nop
+
+.close // CODE_FILE