On 19/10/2022 06:04, Damien Le Moal wrote:
On 10/19/22 14:03, Damien Le Moal wrote:
On 10/18/22 22:24, John Garry wrote:
Hi guys,
In the hisi_sas driver there are times in which we need to issue an ATA
software reset. For this we use hisi_sas_softreset_ata_disk() ->
sas_execute_ata_cmd() -> sas_execute_tmf(), which uses libsas "slow
task" mechanism to issue the command.
Something is wrong here... The reset command sent by that function is
for ATAPI (DEVICE RESET command). There is no device reset command for
SATA disks following the ACS standard.
Yeah, that looks wrong.
So hisi_sas_softreset_ata_disk() seems totally bogus to me, unless you
have a CD/DVD drive connected to the HBA:)
Sure
This is why the softreset function is a port operation defined by LLDs.
How you reset the device depends on the adapter. E.g., for AHCI, you
need to send a host2device FIS with the software reset bit set.
This would be quite a standard method, right?
See: ahci_do_softreset() for AHCI.
For ahci_do_softreset(), do you just implicitly use ATA_CMD_NOP as the
command?
For hisi_sas, maybe ATA_CMD_DEV_RESET is silently ignored when issued
for a SATA disk, but having SRST set/unset still takes effect (and that
is how it still works). I need to check on that.
Thanks,
John
