diff options
Diffstat (limited to 'prog')
| -rw-r--r-- | prog/link.ld | 67 | ||||
| -rw-r--r-- | prog/src/main.c | 6 | ||||
| -rw-r--r-- | prog/src/prog.s.bak (renamed from prog/src/prog.s) | 0 | ||||
| -rw-r--r-- | prog/src/startup.s | 42 |
4 files changed, 107 insertions, 8 deletions
diff --git a/prog/link.ld b/prog/link.ld index 98658c3..4cc02ec 100644 --- a/prog/link.ld +++ b/prog/link.ld @@ -1,16 +1,67 @@ -OUTPUT_ARCH( "riscv" ) -ENTRY(_start) +/* Linker script for RISC-V */ +/* Define memory regions */ MEMORY { - ROM (rx) : ORIGIN = 0x00010000, LENGTH = 0xF0000 # 0x0001_0000 - 0x000F_FFFF - RAM (rwx) : ORIGIN = 0x00100000, LENGTH = 0xFEFFFFF # 0x0010_0000 - 0xFF0F_FFFF + ROM (rx) : ORIGIN = 0x00010000, LENGTH = 0x400 /* 1024 bytes for ROM */ + RAM (rwx) : ORIGIN = 0x00100000, LENGTH = 0x400 /* 1024 bytes for RAM */ } +ENTRY(_start) + +/* Define sections */ SECTIONS { - .text : { *(.text) } > ROM - .data : { *(.data) } > RAM - .bss : { *(.bss) } > RAM - .stack : { *(.stack) } > RAM + /* Code section */ + .text : + { + KEEP(*(.init)) + KEEP(*(.text)) + KEEP(*(.fini)) + KEEP(*(.rodata)) + _etext = .; + } > ROM + + /* Initialized data section */ + .data : AT(_etext) + { + _sdata = .; + KEEP(*(.data)) + _edata = .; + } > RAM + + /* Uninitialized data section */ + .bss : + { + _sbss = .; + KEEP(*(.bss)) + KEEP(*(COMMON)) + _ebss = .; + } > RAM + + /* Stack section */ + .stack (NOLOAD) : + { + _stack_start = .; + . += 0x10; /* Adjust the size as needed */ + _stack_end = .; + } > RAM + + /* Heap section */ + .heap (NOLOAD) : + { + _heap_start = .; + . += 0x10; /* Adjust the size as needed */ + _heap_end = .; + } > RAM } + +/* Define symbols for memory initialization */ +PROVIDE(_start = 0x00010000); +PROVIDE(_etext = _etext); +PROVIDE(_sdata = _sdata); +PROVIDE(_edata = _edata); +PROVIDE(_sbss = _sbss); +PROVIDE(_ebss = _ebss); +PROVIDE(_sstack = _sstack); +PROVIDE(_estack = _estack);
\ No newline at end of file diff --git a/prog/src/main.c b/prog/src/main.c new file mode 100644 index 0000000..1ce067c --- /dev/null +++ b/prog/src/main.c @@ -0,0 +1,6 @@ + + +int main(void) { + while (1) { + } +} diff --git a/prog/src/prog.s b/prog/src/prog.s.bak index 63026c9..63026c9 100644 --- a/prog/src/prog.s +++ b/prog/src/prog.s.bak diff --git a/prog/src/startup.s b/prog/src/startup.s new file mode 100644 index 0000000..7adfb5e --- /dev/null +++ b/prog/src/startup.s @@ -0,0 +1,42 @@ +.section .init +.globl _start +_start: + /* Set up stack pointer */ + la sp, _stack_end + + /* Initialize .data section (copy from LMA to VMA) */ + la t0, _sdata /* VMA start of .data */ + la t1, _edata /* VMA end of .data */ + la t2, _etext /* LMA start of .data in flash */ +copy_data: + beq t0, t1, clear_bss + lw t3, 0(t2) + sw t3, 0(t0) + addi t0, t0, 4 + addi t2, t2, 4 + j copy_data + +clear_bss: + /* Clear .bss section */ + la t0, _sbss /* VMA start of .bss */ + la t1, _ebss /* VMA end of .bss */ +clear_loop: + beq t0, t1, init_libc + sw x0, 0(t0) + addi t0, t0, 4 + j clear_loop + +init_libc: + /* Call libc initialization functions */ + /* call _init */ + + /* Call main function */ + call main + +finalize_libc: + /* Call libc finalization functions */ + /* call _fini */ + +halt: + /* Infinite loop after main returns */ + j halt |