diff options
| -rw-r--r-- | src/boot.S | 29 |
1 files changed, 18 insertions, 11 deletions
@@ -136,30 +136,37 @@ svc: // SVC #0 returns to supervisor mode // TODO: Make supervisor mode return to a specific location // (rather than to a user location) such as the kernel loop - cmp r0, #0 - bne 3f - cps #0x13 - b 1f -3: + cmp r0, #3 + bgt svc_exit + beq svc_000003 cmp r0, #2 - bne 2f + beq svc_000002 + cmp r0, #1 + beq svc_000001 + cmp r0, #1 + beq svc_000000 +svc_000000: + cps #0x13 + b svc_exit +svc_000001: + b svc_exit +svc_000002: ldmfd sp!, {r0-r12,lr} b schedule -2: - cmp r0, #3 - bne 1f +svc_000003: ldr r3, =scheduler ldr r2, [r3, #0] ldr r1, [r2, #8] // sp_base cmp r1, #-1 - beq 1f + beq svc_exit ldr r3, =stacks_table mov r0, #0 strb r0, [r3, r1] // Free the thread after freeing the stack mov r0, r2 bl free -1: + b svc_exit +svc_exit: ldmfd sp!, {r0-r12,pc}^ prefetch: stmfd sp!, {r0-r12,lr} |