Refactored platform code to use interfaces for patch code with a special feature and improved patch code file names

arm9/source/patches/platform/stargate/StargateReadSdDmaPatchCode.s

@@ -0,0 +1,94 @@
+.cpu arm946e-s
+.section "stargate_readsddma", "ax"
+.syntax unified
+.thumb
+
+// r0 = src sector
+// r1 = previous src sector
+// r2 = dma channel
+// r3 = dst
+.global stargate_readSdDma
+.type stargate_readSdDma, %function
+stargate_readSdDma:
+    push {r4-r7,lr}
+
+    ldr r4, =0x040001A0
+    movs r7, #0x80
+    strb r7, [r4,#0x1]
+
+sector_loop:
+    // request sd read for sector 0xaabbccdd
+    // B9 aa bb cc dd 00 00 00
+    movs r7, #0xB9
+    strb r7, [r4,#0x8]
+    lsrs r7, r0, #24
+    strb r7, [r4,#0x9]
+    lsrs r7, r0, #16
+    strb r7, [r4,#0xA]
+    lsrs r7, r0, #8
+    strb r7, [r4,#0xB]
+    lsls r7, r0, #24
+    lsrs r7, r7, #24 // r7 = dd
+    str r7, [r4,#0xC] // storing as little-endian puts the bottom 8 bits as first byte
+
+    ldr r1, =0x04100010
+
+B9_poll_loop:
+    ldr r7, =0xA7406000
+    str r7, [r4,#0x4]
+
+B9_poll_transfer_loop:
+    ldrb r7, [r4,#0x6]
+    lsrs r7, r7, #8
+    bcc B9_poll_check_transfer_end
+    ldr r5, [r1]
+
+B9_poll_check_transfer_end:
+    ldrb r7, [r4,#0x7]
+    lsrs r7, r7, #8
+    bcs B9_poll_transfer_loop
+
+    cmp r5, #0
+    bne B9_poll_loop
+
+    // Setup data read card command
+    movs r7, #0xBA
+    str r7, [r4,#0x8]
+    str r5, [r4,#0xC] // r5 is 0 here
+
+readDataWithDma:
+    movs r0, r2 // DMA channel
+    movs r2, r3 // Destination
+    movs r3, #1
+    lsls r3, r3, #9 // (1 << 9) = 512 = count
+
+    ldr r6, stargate_readSdDma_miiCardDmaCopy32Ptr
+    blx r6
+
+BA_data_dma:
+    movs r7, #0xC0 // select rom mode, with irq
+    strb r7, [r4,#0x1]
+    ldr r7, =0xA1406000
+    str r7, [r4,#0x4]
+
+    pop {r4-r7,pc}
+
+.balign 4
+
+.global stargate_readSdDma_miiCardDmaCopy32Ptr
+stargate_readSdDma_miiCardDmaCopy32Ptr:
+    .word 0
+
+.pool
+
+.global stargate_finishReadSdDma
+.type stargate_finishReadSdDma, %function
+stargate_finishReadSdDma:
+    // No cleanup needed on this platform.
+    bx lr
+
+.balign 4
+
+.pool
+
+.end