scsi: ata: libata: Add ATA feature control sub-page translation

Add support for the ATA feature control sub-page of the control mode page
to enable/disable the command duration limits feature using the cdl_ctrl
field of the ATA feature control sub-page.

Both mode sense and mode select translation are supported. For mode sense,
the ata device flag ATA_DFLAG_CDL_ENABLED is used to cache the status of
the command duration limits feature. Enabling this feature is done using a
SET FEATURES command with a cdl action set to 1 when the page cdl_ctrl
field value is 0x2 (T2A and T2B pages supported). If this field is 0, CDL
is disabled using the SET FEATURES command with a cdl action set to 0.

Since a device CDL and NCQ priority features should not be used
simultaneously, ata_mselect_control_ata_feature() returns an error when
attempting to enable CDL with the device priority feature enabled.
Conversely, the function ata_ncq_prio_enable_store() used to enable the use
of the device NCQ priority feature through sysfs is modified to return an
error if the device CDL feature is enabled.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Co-developed-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Link: https://lore.kernel.org/r/20230511011356.227789-18-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 38 insertions, 2 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 83fe037f63b9..cd7aaf202397 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2371,13 +2371,15 @@ static void ata_dev_config_cdl(struct ata_device *dev)
 {
 	struct ata_port *ap = dev->link->ap;
 	unsigned int err_mask;
+	bool cdl_enabled;
 	u64 val;
 
 	if (ata_id_major_version(dev->id) < 12)
 		goto not_supported;
 
 	if (!ata_log_supported(dev, ATA_LOG_IDENTIFY_DEVICE) ||
-	    !ata_identify_page_supported(dev, ATA_LOG_SUPPORTED_CAPABILITIES))
+	    !ata_identify_page_supported(dev, ATA_LOG_SUPPORTED_CAPABILITIES) ||
+	    !ata_identify_page_supported(dev, ATA_LOG_CURRENT_SETTINGS))
 		goto not_supported;
 
 	err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
@@ -2397,6 +2399,40 @@ static void ata_dev_config_cdl(struct ata_device *dev)
 			"Command duration guideline is not supported\n");
 
 	/*
+	 * If CDL is marked as enabled, make sure the feature is enabled too.
+	 * Conversely, if CDL is disabled, make sure the feature is turned off.
+	 */
+	err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
+				     ATA_LOG_CURRENT_SETTINGS,
+				     ap->sector_buf, 1);
+	if (err_mask)
+		goto not_supported;
+
+	val = get_unaligned_le64(&ap->sector_buf[8]);
+	cdl_enabled = val & BIT_ULL(63) && val & BIT_ULL(21);
+	if (dev->flags & ATA_DFLAG_CDL_ENABLED) {
+		if (!cdl_enabled) {
+			/* Enable CDL on the device */
+			err_mask = ata_dev_set_feature(dev, SETFEATURES_CDL, 1);
+			if (err_mask) {
+				ata_dev_err(dev,
+					    "Enable CDL feature failed\n");
+				goto not_supported;
+			}
+		}
+	} else {
+		if (cdl_enabled) {
+			/* Disable CDL on the device */
+			err_mask = ata_dev_set_feature(dev, SETFEATURES_CDL, 0);
+			if (err_mask) {
+				ata_dev_err(dev,
+					    "Disable CDL feature failed\n");
+				goto not_supported;
+			}
+		}
+	}
+
+	/*
 	 * Command duration limits is supported: cache the CDL log page 18h
 	 * (command duration descriptors).
 	 */
@@ -2412,7 +2448,7 @@ static void ata_dev_config_cdl(struct ata_device *dev)
 	return;
 
 not_supported:
-	dev->flags &= ~ATA_DFLAG_CDL;
+	dev->flags &= ~(ATA_DFLAG_CDL | ATA_DFLAG_CDL_ENABLED);
 }
 
 static int ata_dev_config_lba(struct ata_device *dev)