On 8/31/23 12:09, Szuying Chen wrote:
> This patch adds the function to clear pending interrupt before COMRESET.
> It follows the AHCI1.3.1 - section6.2.2.2 specification.
Please explain here the relevant part of that section.
>
> Signed-off-by: Szuying Chen <Chloe_Chen@xxxxxxxxxxxxxx>
> ---
> drivers/ata/libahci.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
> index 06aec35f88f2..1ae788251a6c 100644
> --- a/drivers/ata/libahci.c
> +++ b/drivers/ata/libahci.c
> @@ -1584,6 +1584,23 @@ static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
> return rc;
> }
>
> +static void PortClearPendingInterrupt(struct ata_port *ap)
No CaMeLCaSe please ! Call this ahci_port_clear_peinding_irq().
> +{
> + struct ahci_host_priv *hpriv = ap->host->private_data;
> + void __iomem *port_mmio = ahci_port_base(ap);
> + u32 tmp;
> +
> + /* clear port SERR */
> + tmp = readl(port_mmio + PORT_SCR_ERR);
> + writel(tmp, port_mmio + PORT_SCR_ERR);
> +
> + /* clear port IRQ */
> + tmp = readl(port_mmio + PORT_IRQ_STAT);
> + writel(tmp, port_mmio + PORT_IRQ_STAT);
> +
> + writel(1 << ap->port_no, hpriv->mmio + HOST_IRQ_STAT);
This code is nearly identical to what ahci_port_init() does. So better make it
common: keep the debug messages that are in ahci_port_init() and modify that
function to call this new helper.
> +}
> +
> int ahci_do_hardreset(struct ata_link *link, unsigned int *class,
> unsigned long deadline, bool *online)
> {
> @@ -1602,6 +1619,9 @@ int ahci_do_hardreset(struct ata_link *link, unsigned int *class,
> tf.status = ATA_BUSY;
> ata_tf_to_fis(&tf, 0, 0, d2h_fis);
>
> + /* clear pending Interrupt */
> + PortClearPendingInterrupt(ap);
> +
> rc = sata_link_hardreset(link, timing, deadline, online,
> ahci_check_ready);
>
> --
> 2.39.2
>
--
Damien Le Moal
Western Digital Research
