projects / thirdparty / binutils-gdb.git / blame
| Commit | Line | Data |
|---|---|---|
| d9c61e83 AC |
1 | .globl _start |
| 2 | # | |
| 3 | # NOTE: Registers r10-r11 are reserved for the interrupt handler | |
| 4 | # while the others can be used by the main loop/start code. | |
| 5 | ||
| 6 | _start: | |
| 7 | # patch the external interrupt handlers entry | |
| 8 | add r1, r0, handler | |
| 9 | ldw r2, @(r1, 0) | |
| 10 | ldw r3, @(r1, 4) | |
| 11 | add r1, r0, 0xfffff138 | |
| 12 | stw r2, @(r1, 0) | |
| 13 | stw r3, @(r1, 4) | |
| 14 | ||
| 15 | # enable external interrupts - cr0 == PSW | |
| 16 | mvfsys r2, cr0 | |
| 17 | or r2, r0, 0x04000000 | |
| 18 | mvtsys cr0, r2 | |
| 19 | ||
| 20 | ||
| 21 | # wait for flag to be set | |
| 22 | loop: | |
| 23 | add r2, r0, flag | |
| 24 | ldw r3, @(r2, 0) | |
| 25 | bratzr r3, loop | |
| 26 | ||
| 27 | # clear the flag | |
| 28 | stw r0, @(r2, 0) | |
| 29 | ||
| 30 | add r2, r0, tick | |
| 31 | # putstr | |
| 32 | .long 0x0e000001, 0x00f00000 | |
| 33 | ||
| 34 | bra loop | |
| 35 | ||
| 36 | # finished | |
| 37 | add r2, r0, r0 || nop | |
| 38 | .long 0x0e000004, 0x00f00000 | |
| 39 | ||
| 40 | ||
| 41 | handler: | |
| 42 | jmp real_handler | |
| 43 | real_handler: | |
| 44 | add r10, r0, 1 | |
| 45 | add r11, r0, flag | |
| 46 | stb r10, @(r11,0) | |
| 47 | reit | |
| 48 | ||
| 49 | ||
| 50 | flag: .long 0 | |
| 51 | tick: .ascii "Tick\r\n" |