Re: [PATCH] hw/ide/ahci: fix legacy software reset

[Marcin Juszkiewicz]

W dniu 5.10.2023 o 11:53, Niklas Cassel pisze:
> From: Niklas Cassel<niklas.cassel@wdc.com>
>
> Legacy software contains a standard mechanism for generating a reset to a
> Serial ATA device - setting the SRST (software reset) bit in the Device
> Control register.
>
> Serial ATA has a more robust mechanism called COMRESET, also referred to
> as port reset. A port reset is the preferred mechanism for error
> recovery and should be used in place of software reset.
>
> Commit e2a5d9b3d9c3 ("hw/ide/ahci: simplify and document PxCI handling")
> improved the handling of PxCI, such that PxCI gets cleared after handling
> a non-NCQ, or NCQ command (instead of incorrectly clearing PxCI after
> receiving an arbitrary FIS).
>
> However, simply clearing PxCI after a non-NCQ, or NCQ command, is not
> enough, we also need to clear PxCI when receiving a SRST in the Device
> Control register.
>
> This fixes an issue for FreeBSD where the device would fail to reset.
> The problem was not noticed in Linux, because Linux uses a COMRESET
> instead of a legacy software reset by default.
>
> Fixes: e2a5d9b3d9c3 ("hw/ide/ahci: simplify and document PxCI handling")
> Reported-by: Marcin Juszkiewicz<marcin.juszkiewicz@linaro.org>
> Signed-off-by: Niklas Cassel<niklas.cassel@wdc.com>

Sorry, I missed that patch earlier.

FreeBSD 14-rc3 boots fine on aarch64. Thanks!

Trying to mount root from cd9660:/dev/iso9660/14_0_RC3_AARCH64_BO [ro]...
cd0 at ahcich0 bus 0 scbus0 target 0 lun 0
cd0: <QEMU QEMU DVD-ROM 2.5+> Removable CD-ROM SCSI device
cd0: Serial Number QM00001
cd0: 150.000MB/s transfers (SATA 1.x, UDMA5, ATAPI 12bytes, PIO 8192bytes)
cd0: 347MB (177954 2048 byte sectors)
ada0 at ahcich1 bus 0 scbus1 target 0 lun 0
ada0: <QEMU HARDDISK 2.5+> ATA-7 SATA device
ada0: Serial Number QM00003
ada0: 150.000MB/s transfers (SATA 1.x, UDMA5, PIO 8192bytes)
ada0: Command Queueing enabled
ada0: 504MB (1032192 512 byte sectors)
ada1 at ahcich2 bus 0 scbus2 target 0 lun 0
ada1: <QEMU HARDDISK 2.5+> ATA-7 SATA device
ada1: Serial Number QM00005
ada1: 150.000MB/s transfers (SATA 1.x, UDMA5, PIO 8192bytes)
ada1: Command Queueing enabled
ada1: 8192MB (16777216 512 byte sectors)

Tested-by: Marcin Juszkiewicz<marcin.juszkiewicz@linaro.org>