diff options
| -rw-r--r-- | boot.subx | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/boot.subx b/boot.subx index 438829cf..281f9287 100644 --- a/boot.subx +++ b/boot.subx @@ -943,7 +943,8 @@ load-first-sector-from-primary-bus-secondary-drive: # out: (addr stream byte) (ata-lba 0 0 0) # lower 24 bits of LBA, all 0 (ata-command 0x20) # read sectors with retries # poll for results - (poll-ata-regular-status-word) + (while-ata-busy) + (until-ata-data-available) # emit results ba/copy-to-edx 0x1f0/imm32 b9/copy-to-ecx 0x200/imm32 # 512 bytes per sector @@ -1173,7 +1174,7 @@ $ata-command:end: 5d/pop-to-ebp c3/return -poll-ata-regular-status-word: +while-ata-busy: # . save registers 50/push-eax 52/push-edx @@ -1183,10 +1184,26 @@ poll-ata-regular-status-word: ec/read-port-dx-into-al a8/test-bits-in-al 0x80/imm8/bsy # set zf if bit 7 (most significant) is not set 75/jump-if-zf-not-set-and-bit-7-set loop/disp8 + } +$while-ata-busy:end: + # . restore registers + 5a/pop-to-edx + 58/pop-to-eax + # . epilogue + c3/return + +until-ata-data-available: + # . save registers + 50/push-eax + 52/push-edx + # + ba/copy-to-edx 0x1f7/imm32 + { + ec/read-port-dx-into-al a8/test-bits-in-al 8/imm8/drq # set zf if bit 3 is not set 74/jump-if-zf-set-and-bit-3-not-set loop/disp8 } -$poll-ata-regular-status-word:end: +$while-ata-busy:end: # . restore registers 5a/pop-to-edx 58/pop-to-eax |