audk/MdeModulePkg/Bus/Ata
Cinnamon Shia 2d273c8db9 MdeModulePkg/AtaBusDxe: Fix some ATA hard drives cannot be discovered
If there is no multiplier, the DEV bit of the ATA device register would
always be set. It causes that some ATA hard drives don't response the
ATA identity command sent to them.

Below is the description about DEV bit in ATA spec:
A device is selected when the DEV bit of the Device register is equal to
the device number assigned to the device by means of a Device 0/Device 1
jumper or switch, or use of the CSEL signal.

Below is the description about DEV bit in SATA spec:
When the DEV bit in the Device register is set to one, selecting the
non-existent Device 1, the host adapter shall respond to register reads
and writes as specified for a Device 0 with no Device 1 present, as
defined in the ATA/ATAPI-5 standard.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Cinnamon Shia <cinnamon.shia@hpe.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
2016-06-07 08:44:32 +08:00
..
AtaAtapiPassThru MdeModulePkg AtaAtapiPassThru: Fix incorrect parameter description comment 2016-05-12 14:18:16 +08:00
AtaBusDxe MdeModulePkg/AtaBusDxe: Fix some ATA hard drives cannot be discovered 2016-06-07 08:44:32 +08:00