Thread Local Storage
Each thread is given a 0x200-byte thread-local-storage block by the kernel. It is used during IPC communications. Each KProcess has a linked list of KThreadLocalPage objects and each object has a pointer to a page(0x1000 bytes) of FCRAM, which is used for up to 8 thread-local-storage blocks. The KThreadLocalPage is used to track which thread-local-storage blocks are used so it can allocate new ones as new threads are created.
A pointer to the thread-local-storage can be read using the ARM instruction:
mrc 15, 0, rX, cr13, cr0, 3
Every application has RW access to its thread-local-storage.
The kernel requires the application to put IPC parameters and IPC static buffers inside the thread-local-storage:
|0||0x80||Undefined, can be used by application for any purpose.|
|0x80||0x100||IPC command with parameters|
|0x180||0x80||IPC static buffers: 16 pairs of a static buffer translation descriptor (specifying the buffer size) and a buffer pointer|