diff options
Diffstat (limited to 'qemu/roms/openbios/arch/ppc/timebase.S')
| -rw-r--r-- | qemu/roms/openbios/arch/ppc/timebase.S | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/qemu/roms/openbios/arch/ppc/timebase.S b/qemu/roms/openbios/arch/ppc/timebase.S new file mode 100644 index 000000000..19faed49d --- /dev/null +++ b/qemu/roms/openbios/arch/ppc/timebase.S @@ -0,0 +1,33 @@ +#include "asm/asmdefs.h" +#include "asm/processor.h" + +/* + * unsigned long long _get_ticks(void); + */ +_GLOBAL(_get_ticks): +1: mftbu r3 + mftb r4 + mftbu r5 + cmpw 0,r3,r5 + bne 1b + blr + +/* + * Delay for a number of ticks + */ +_GLOBAL(_wait_ticks): + mflr r8 /* save link register */ + mr r7, r3 /* save tick count */ + bl BRANCH_LABEL(_get_ticks) /* Get start time */ + + /* Calculate end time */ + addc r7, r4, r7 /* Compute end time lower */ + addze r6, r3 /* and end time upper */ + +1: bl BRANCH_LABEL(_get_ticks) /* Get current time */ + subfc r4, r4, r7 /* Subtract current time from end time */ + subfe. r3, r3, r6 + bge 1b /* Loop until time expired */ + + mtlr r8 /* restore link register */ + blr |