Changes

Jump to navigation Jump to search
96 bytes removed ,  21:42, 7 June 2015
no edit summary
Line 4: Line 4:  
  struct DmaConfig {
 
  struct DmaConfig {
 
     sint8_t channel_sel; // @0 Selects which DMA channel to use: 0-7, -1 = don't care.
 
     sint8_t channel_sel; // @0 Selects which DMA channel to use: 0-7, -1 = don't care.
     uint8_t endian_swap_size; // @1 Accepted values: 0=none,2=16bit,4=32bit,8=64bit.
+
     uint8_t endian_swap_size; // @1 Accepted values: 0=none, 2=16bit, 4=32bit, 8=64bit.
     uint8_t flags;       // @2 bit0: DST_CFG, bit1: SRC_CFG, bit2: SHALL_BLOCK, bit3: ???, bit6: DST_ALT_CFG, bit7: SRC_ALT_CFG
+
     uint8_t flags; // @2 bit0: DST_CFG, bit1: SRC_CFG, bit2: SHALL_BLOCK, bit3: ???, bit6: DST_ALT_CFG, bit7: SRC_ALT_CFG
 
     uint8_t padding;
 
     uint8_t padding;
     uint8_t dst_cfg[10];
+
    DmaSubConfig dst_cfg;
     // @5 Accepted values (u8): 4, 8, 12, 15.
+
    DmaSubConfig src_cfg;
     // @15 Accepted values (u8): 4, 8, 12, 15.
+
}
     uint8_t src_cfg[10]; // @14
+
 
 +
struct DmaSubConfig {
 +
     uint8_t peripheral_id; // @0
 +
     uint8_t unk2; // @1 Accepted values: 4, 8, 12, 15
 +
     uint16_t unk3; // @2
 +
    uint16_t transfer_size?; // @4
 +
     uint16_t unk4; // @6
 +
    uint16_t transfer_stride?; // @8
 
  }
 
  }
   Line 16: Line 23:     
If CFG or ALT_CFG is not set, default configuration is loaded:
 
If CFG or ALT_CFG is not set, default configuration is loaded:
FF 0F 80 00 00 00 80 00 00 00
     −
If SHALL_BLOCK is set, the thread will sleep until the DMA engine is ready. If not set, the SVC will return 0xD04007F0 if the DMA channel is busy.
+
.peripheral_id = 0xFF,
 +
.unk2 = 0xF,
 +
.unk3 = 0x80,
 +
.transfer_size = 0,
 +
.unk4 = 0x80,
 +
.unk5 = 0,
   −
The format of src_cfg/dst_cfg is unknown, but both have the same format. Checks suggest that the second byte of cfg equalling 4 means NO_INCREMENT (don't increment after read/write).
+
Checks suggest that unk2 of DmaSubConfig equalling 4 means NO_INCREMENT (don't increment after read/write).
   −
Each src/dst config:
+
If SHALL_BLOCK is set, the thread will sleep until the DMA engine is ready. If not set, the SVC will return 0xD04007F0 if the DMA channel is busy.
struct DmaSubConfig {
  −
    uint8_t peripheral_id;  // @0
  −
    uint8_t unk2;  // @1 Seen: 2
  −
    uint16_t unk3; // @2
  −
    uint16_t transfer_size?; // @4
  −
    uint16_t unk4; // @6
  −
    uint16_t unk5; // @8
  −
}
      
The generated bytecode starts with a FLUSHP on the peripheral_ids for src/dst (if specified). After that, it always moves 0 into DAR. Then it moves the src/dst addresses into SAR/DAR respectively...
 
The generated bytecode starts with a FLUSHP on the peripheral_ids for src/dst (if specified). After that, it always moves 0 into DAR. Then it moves the src/dst addresses into SAR/DAR respectively...
110

edits

Navigation menu