On 2022/03/03 5:49, Mario Limonciello wrote:
> As the default low power policy applies to more chipsets and drives, it's
> important to make sure that drives actually support the policy that a user
> selected in their kernel configuration.
>
> If the drive doesn't support slumber, don't let the default policies
> dependent upon slumber (`min_power` or `min_power_with_partial`) affect the
> disk.
>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> Changes from v1->v2:
> * Move deeper into codepaths
> * Reset to MED_POWER rather than ignore
> drivers/ata/libata-sata.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
> index 071158c0c44c..0dc03888c62b 100644
> --- a/drivers/ata/libata-sata.c
> +++ b/drivers/ata/libata-sata.c
> @@ -13,6 +13,7 @@
> #include <scsi/scsi_device.h>
> #include <linux/libata.h>
>
> +#include "ahci.h"
> #include "libata.h"
> #include "libata-transport.h"
>
> @@ -368,10 +369,20 @@ int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
> bool spm_wakeup)
> {
> struct ata_eh_context *ehc = &link->eh_context;
> + struct ata_port *ap = link->ap;
> + struct ahci_host_priv *hpriv;
> bool woken_up = false;
> u32 scontrol;
> int rc;
>
> + hpriv = ap->host->private_data;
> + if (policy >= ATA_LPM_MIN_POWER_WITH_PARTIAL &&
> + !(hpriv->cap & HOST_CAP_SSC)) {
Weird indentation.
> + dev_warn(ap->host->dev,
> + "This drive doesn't support slumber; restting policy to MED_POWER\n");
Typo. I would change this to:
"This device does not support slumber; defaulting to MED_POWER policy\n"
> + policy = ATA_LPM_MED_POWER;
> + }
> +
> rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
> if (rc)
> return rc;
--
Damien Le Moal
Western Digital Research
