Re: [PATCH v4] ahci: libahci: clear pending interrupt status

From: Damien Le Moal
Date: Mon Sep 11 2023 - 02:22:09 EST


On 9/7/23 17:17, Szuying Chen wrote:
> When a CRC error occurs, the HBA asserts an interrupt to indicate an
> interface fatal error(PxIS.IFS). The ISR clear PxIE and PxIS, then do
> error recovery. Before recovery process, HBA receives another SDB FIS
> with the error(PxIS.TFES) from device. This can't be serviced due to
> PxIE be cleared already. During error recovery process, the HBA can't
> issue any new command after setting PxCMD.ST to 1 due to PxIS.TFES
> still alive.
>
> According to AHCI 1.3.1 - section 6.2.2 specification. Fatal errors
> (signified by the setting of PxIS.HBFS, PxIS.HBDS, PxIS.IFS or PxIS.TFES)
> will cause the HBA to enter the ERR:Fatal state. In this state, the HBA
> shall not issue any new commands.
>
> To avoid this, introduce the function ahci_port_clear_pending_irq()
> to clear pending interrupts before executing a COMRESET. This follows
> the AHCI 1.3.1 - section 6.2.2.2 specification.
>
> Signed-off-by: Szuying Chen <Chloe_Chen@xxxxxxxxxxxxxx>

Applied to for-6.6-fixes with some tweaks to the commit message.
Thanks !

--
Damien Le Moal
Western Digital Research