GSP Shared Memory

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This page describes the GX commands which can be written to GSP shared memory. After writing the command data to GSP shared memory, TriggerCmdReqQueue must be used to trigger GSP processing for the command.

Command Buffer Header

Index Byte Description
0 Command Index, must be <=15
1 Must not be value 0
2 Must not be value 1
3 Bit0 must not be set

The command buffer is located at sharedmem + 0x800 + threadindex*0x200.

Command Header

Index Byte Description
0 Command ID
2-1 ?
3 When non-zero GSP module may check flags for the specified cmdID, command handling is aborted when the flags are set.

The command is located at cmdbuf + 0x20 + cmdindex*0x20, the size of each command is 0x20-bytes. The command parameters are located at command+4. Application vaddrs specified in command parameters can usually be located in either the application GSP heap at 0x14000000 or VRAM.

Commands

GX Command 0

Index Word Description
0 u8 CommandID is 0x00

This command is normally used to DMA data from the application GSP heap at 0x14000000 to VRAM.

GX Command 1

Index Word Description
0 u8 CommandID is 0x01

GX Command 2

Index Word Description
0 u8 CommandID is 0x02

GX Command 3

Index Word Description
0 u8 CommandID is 0x03

GX Command 4

Index Word Description
0 u8 CommandID is 0x04

GX Command 5

Index Word Description
0 u8 CommandID is 0x05

The application buffer addresses specified in the parameters are used with svcFlushProcessDataCache.