On 5/2/24 6:26 PM, Niklas Cassel wrote:
> From: Mario Limonciello <mario.limonciello@xxxxxxx>
>
> Historically this was set to "keep_firmware_settings" to prevent problems
> with power management on very old drives. However it's been observed that
> almost all modern Linux distributions either set the policy to
> "med_power_with_dipm" in the kernel configuration or update it to this via
> userspace policy changes. Update the policy default in the kernel to
> "med_power_with_dipm" to match that behavior as well.
>
> Changing the default was previously not a good idea, because LPM disables
> detection of hot plug removals, however, since commit ae1f3db006b7 ("ata:
> ahci: do not enable LPM on external ports"), a port marked as external
> will always be initialized to "keep_firmware_settings", regardless of the
> SATA_MOBILE_LPM_POLICY Kconfig value. Therefore, changing the default is
> now considered safe (external ports included).
>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> [cassel: rebased and reworded commit message]
> Signed-off-by: Niklas Cassel <cassel@xxxxxxxxxx>
All distributions use this, so doing the same will potentially allow us to
catch buggy hardware earlier while in linux-next testing phase. So yes.
Reviewed-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
> ---
> drivers/ata/Kconfig | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index b595494ab9b4..e00536b49552 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -118,7 +118,7 @@ config SATA_AHCI
> config SATA_MOBILE_LPM_POLICY
> int "Default SATA Link Power Management policy"
> range 0 4
> - default 0
> + default 3
> depends on SATA_AHCI
> help
> Select the Default SATA Link Power Management (LPM) policy to use
--
Damien Le Moal
Western Digital Research
