diff options
Diffstat (limited to 'sys/dev/ata/chipsets/ata-serverworks.c')
| -rw-r--r-- | sys/dev/ata/chipsets/ata-serverworks.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sys/dev/ata/chipsets/ata-serverworks.c b/sys/dev/ata/chipsets/ata-serverworks.c index 29718ec5e48b..cee56e3681ee 100644 --- a/sys/dev/ata/chipsets/ata-serverworks.c +++ b/sys/dev/ata/chipsets/ata-serverworks.c @@ -241,6 +241,16 @@ ata_serverworks_ch_attach(device_t dev) ATA_OUTL(ctlr->r_res2, ch_offset + 0x88, 0); ATA_OUTL(ctlr->r_res2, ch_offset + 0x80, ATA_INL(ctlr->r_res2, ch_offset + 0x80) & ~0x00040000); + + /* + * Some controllers have a bug where they will send the command + * to the drive before seeing a DMA start, and then can begin + * receiving data before the DMA start arrives. The controller + * will then become confused and either corrupt the data or crash. + * Remedy this by starting DMA before sending the drive command. + */ + + ch->flags |= ATA_DMA_BEFORE_CMD; } /* chip does not reliably do 64K DMA transfers */ |