ahci: implement aggressive SATA device sleep support
Device Sleep is a feature as described in AHCI 1.3.1 Technical Proposal.
This feature enables an HBA and SATA storage device to enter the DevSleep
interface state, enabling lower power SATA-based systems.
Aggressive Device Sleep enables the HBA to assert the DEVSLP signal as
soon as there are no commands outstanding to the device and the port
specific Device Sleep idle timer has expired. This enables autonomous
entry into the DevSleep interface state without waiting for software
in power sensitive systems.
This patch enables Aggressive Device Sleep only if both host controller
and device support it.
Tested on AMD reference board together with Device Sleep supported device
sample.
Signed-off-by: Shane Huang <shane.huang@amd.com>
Reviewed-by: Aaron Lu <aaron.lwe@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 64f90e1..464e67c 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -162,6 +162,7 @@
ATA_DFLAG_DETACHED = (1 << 25),
ATA_DFLAG_DA = (1 << 26), /* device supports Device Attention */
+ ATA_DFLAG_DEVSLP = (1 << 27), /* device supports Device Sleep */
ATA_DEV_UNKNOWN = 0, /* unknown device */
ATA_DEV_ATA = 1, /* ATA device */
@@ -649,6 +650,9 @@
u32 gscr[SATA_PMP_GSCR_DWORDS]; /* PMP GSCR block */
};
+ /* Identify Device Data Log (30h), SATA Settings (page 08h) */
+ u8 sata_settings[ATA_SECT_SIZE];
+
/* error history */
int spdn_cnt;
/* ering is CLEAR_END, read comment above CLEAR_END */