psx 0.1.6

Library for developing homebrew for the Sony PlayStation 1
Documentation 
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RAM_BASE = 0x80000000;
RAM_SIZE = 2M;
BIOS_SIZE = 64K;
HEADER_SIZE = 2K;
LOAD_OFFSET = 0;
LOAD_ADDR = RAM_BASE + BIOS_SIZE + LOAD_OFFSET;
STACK_INIT = RAM_BASE + 0x001FFF00;

MEMORY {
    HEADER    : ORIGIN = LOAD_ADDR - HEADER_SIZE, LENGTH = HEADER_SIZE
    RAM (rwx) : ORIGIN = LOAD_ADDR, LENGTH = RAM_SIZE - (LOAD_ADDR - RAM_BASE)
}

ENTRY(__start)

SECTIONS {
    .psx_exe_header : {
        /* ASCII ID "PS-X EXE" */
        BYTE(0x50); BYTE(0x53); BYTE(0x2d); BYTE(0x58);
        BYTE(0x20); BYTE(0x45); BYTE(0x58); BYTE(0x45);
        /* Unused */
        QUAD(0);
        /* Initial PC */
        LONG(ABSOLUTE(__start));
        /* Initial GP/R28 */
        LONG(_gp);
        /* Load address */
        LONG(LOAD_ADDR);
        /* File size excluding the 2K header */
        LONG(__bss_start - __text_start);
        /* Unused */
        QUAD(0); QUAD(0);
        /* Initial SP/R29 and FP/R30 base */
        LONG(STACK_INIT);
        /* Initial SP/R29 and FP/R30 offset */
        LONG(0);
        /* Unused */
        QUAD(0); QUAD(0); LONG(0);
        /* ASCII region marker */
        KEEP(*(.region));
        . = ALIGN(HEADER_SIZE);
    } > HEADER

    .text : {
        __text_start = .;
        __ctors_start = .;
        *(.ctors*)
        __ctors_end = .;
        ASSERT((__ctors_end - __ctors_start) % 4 == 0, "Invalid .ctors section");
        __dtors_start = .;
        *(.dtors*)
        __dtors_end = .;
        ASSERT((__dtors_end - __dtors_start) % 4 == 0, "Invalid .dtors section");
        *(.text*)
        __text_end = .;
    } > RAM

    /* The PSX doesn't have an MMU so we don't really care about RO vs RW */
    .data : {
        __data_start = .;
        *(.data*)
        *(.rodata*)
        *(.got)
        /* Padding to a multiple of 2K is required for loading from ISO */
        . = ALIGN(2048);
        __data_end = .;
    } > RAM

    .bss (NOLOAD) : {
        __bss_start = .;
        *(.bss*)
        *(COMMON)
        __bss_end = .;
    } > RAM

    /* Make the heap word-aligned */
    . = ALIGN(4);
    __heap_start = .;

    /DISCARD/ : {
        *(.MIPS.abiflags)
        *(.reginfo)
        *(.eh_frame_hdr)
        *(.eh_frame)
    }
}