initial commit

bootloader/Start.S

@@ -0,0 +1,56 @@
+.section ".text.boot"
+
+.global _start
+
+_start:
+	mrs x1, mpidr_el1
+	and x1, x1, #3
+	cbz x1, run
+	
+wait:
+	wfe
+	b wait
+
+run:
+	mov x20, x0
+	adr x0, _start
+	mov sp, x0
+
+	adr x0, __text_start
+	ldr x1, =__new_text_start
+	cmp x0, x1
+	b.gt relocate
+
+	adr x0, __bss_start
+	adr x1, __bss_end
+	bl memzero
+
+	mov x0, x20
+	bl main
+	b wait
+
+relocate:
+	// move text section
+	ldr x0, =__new_text_start
+	adr x1, __text_start
+	adr x2, __text_end
+	sub x2, x2, x1
+	bl memcpy
+	mov x19, x0
+
+	// move rodata section
+	ldr x0, =__new_ro_start
+	adr x1, __rodata_start
+	adr x2, __rodata_end
+	sub x2, x2, x1
+	bl memcpy
+	
+	// move data section
+	ldr x0, =__new_data_start
+	adr x1, __data_start
+	adr x2, __data_end
+	sub x2, x2, x1
+	bl memcpy
+
+	br x19
+	b wait

bootloader/linker.ld

@@ -0,0 +1,50 @@
+ENTRY(_start)
+MEMORY
+{
+  NEWTEXT (rx) : ORIGIN = 0x10000, LENGTH = 128K
+  NEWRO (r) : ORIGIN = 0x30000, LENGTH = 128K
+  NEWDATA (rw) : ORIGIN = 0x50000, LENGTH = 64K
+  NEWBSS (rw) : ORIGIN = 0x60000, LENGTH = 64K
+
+  TEXT (rx) : ORIGIN = 0x80000, LENGTH = 128K
+  RO (r) : ORIGIN = 0xa0000, LENGTH = 128K
+  DATA (rw) : ORIGIN = 0xc0000, LENGTH = 64K
+  BSS (rw) : ORIGIN = 0xd0000, LENGTH = 64K
+  RAM (rw) : ORIGIN = 0xf0000, LENGTH = 8M
+}
+
+SECTIONS
+{
+  .text : { 
+    __text_start = .;
+    KEEP(*(.text.boot))
+    *(.text)
+    __text_end = .;
+  } >TEXT
+  .rodata : {
+    __rodata_start = .;
+    *(.rodata)
+    __rodata_end = .;
+  } >RO
+  .data : {
+    __data_start = .;
+    *(.data)
+    __data_end = .;
+  } >DATA
+  .bss : {
+    __bss_start = .;
+    *(.bss)
+    __bss_end = .;
+  } >BSS
+  __stack_end = ORIGIN(RAM) + LENGTH(RAM);
+
+  __new_text_start = ORIGIN(NEWTEXT);
+  __new_ro_start = ORIGIN(NEWRO);
+  __new_data_start = ORIGIN(NEWDATA);
+  __new_bss_start = ORIGIN(NEWBSS);
+}
+
+__kernel = 0x80000;
+__heap_start = ORIGIN(RAM);
+__heap_end = ORIGIN(RAM) + LENGTH(RAM) - 2M;
+__bss_size = (__bss_end - __bss_start)>>3;

bootloader/main.c

@@ -0,0 +1,21 @@
+#include <stddef.h>
+#include <shell.h>
+#include <uart.h>
+
+extern byte_t __kernel[];
+byte_t *kernel = __kernel;
+
+void main()
+{
+  uart_init();
+
+  uart_getc();
+  uart_puts("loaded addr: ");
+  uart_hex((unsigned int)(unsigned long)main);
+  uart_puts(ENDL);
+  
+  int shell_cont = 1;
+  while (shell_cont) {
+    shell_cont = shell();
+  }
+}