From f7870e8d345cdabfb94bcbdcba6a07e050f8705e Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Tue, 1 Jul 2025 21:53:17 +0900 Subject: [PATCH] ata: ahci: Disable DIPM if host lacks support MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The AHCI specification version 1.3.1 section 8.3.1.4 (Software Requirements and Precedence) states that: If CAP.SSC or CAP.PSC is cleared to ‘0’, software should disable device-initiated power management by issuing the appropriate SET FEATURES command to the device. To satisfy this constraint and force ata_dev_configure to disable the device DIPM feature, modify ahci_update_initial_lpm_policy() to set the ATA_FLAG_NO_DIPM flag on ports that have a host with either the ATA_HOST_NO_PART flag set or the ATA_HOST_NO_SSC flag set. Signed-off-by: Damien Le Moal Reviewed-by: Niklas Cassel Reviewed-by: Hannes Reinecke Reviewed-by: Hannes Reinecke Link: https://lore.kernel.org/r/20250701125321.69496-7-dlemoal@kernel.org Signed-off-by: Niklas Cassel --- drivers/ata/ahci.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 1b4151d95888d..0760fa47d90ec 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1780,6 +1780,13 @@ static void ahci_update_initial_lpm_policy(struct ata_port *ap) return; } + /* If no Partial or no Slumber, we cannot support DIPM. */ + if ((ap->host->flags & ATA_HOST_NO_PART) || + (ap->host->flags & ATA_HOST_NO_SSC)) { + ata_port_dbg(ap, "Host does not support DIPM\n"); + ap->flags |= ATA_FLAG_NO_DIPM; + } + /* If no LPM states are supported by the HBA, do not bother with LPM */ if ((ap->host->flags & ATA_HOST_NO_PART) && (ap->host->flags & ATA_HOST_NO_SSC) && -- 2.47.3