diff options
Diffstat (limited to 'libc/sysdeps/linux/arm/crt0.S')
| -rw-r--r-- | libc/sysdeps/linux/arm/crt0.S | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/arm/crt0.S b/libc/sysdeps/linux/arm/crt0.S index 65253881c..de7ef7848 100644 --- a/libc/sysdeps/linux/arm/crt0.S +++ b/libc/sysdeps/linux/arm/crt0.S @@ -6,6 +6,18 @@ NULL env[0...N] environment variables (pointers) NULL + + For uClinux it looks like this: + + argc argument counter (integer) + argv char *argv[] + envp char *envp[] + argv[0] program name (pointer) + argv[1...N] program args (pointers) + argv[argc-1] end of args (integer) + NULL + env[0...N] environment variables (pointers) + NULL When we are done here, we want a1=argc @@ -34,6 +46,7 @@ ARM register quick reference: pc r15 program counter */ +#include <features.h> .text .global _start @@ -44,10 +57,17 @@ ARM register quick reference: .text _start: +#if 0 /* some old code the I feel should not be here - davidm */ + @ adjust the data segment base pointer + ldr r3,=__data_start + sub sl,sl,r3 + mov BASEREG,sl +#endif /* clear the frame pointer */ mov fp, #0 +#ifdef __UCLIBC_HAS_MMU__ /* Load register r0 (argc) from the stack to its final resting place */ ldr r0, [sp], #4 @@ -58,6 +78,16 @@ _start: we find there (hopefully the environment) in r2 */ add r2, r1, r0, lsl #2 add r2, r2, #4 +#else + /* + * uClinux stacks look a little different to MMU stacks + * for no good reason + */ + /* pull argc, argv and envp off the stack */ + ldr r0,[sp, #0] + ldr r1,[sp, #4] + ldr r2,[sp, #8] +#endif /* Ok, now run uClibc's main() -- shouldn't return */ bl __uClibc_main |