scsi: ata: libata: Detect support for command duration limits

Use the supported capabilities identify device data log page to detect if a
device supports the command duration limits feature. For devices supporting
this feature, set the device flag ATA_DFLAG_CDL. To support SCSI-ATA
translation, retrieve the command duration limits log page 18h and cache
this page content using the cdl array added to the ata_device data
structure.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.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/20230511011356.227789-15-nks@flawful.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 51 insertions, 1 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 8bf612bdd61a..83fe037f63b9 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2367,6 +2367,54 @@ static void ata_dev_config_trusted(struct ata_device *dev)
 		dev->flags |= ATA_DFLAG_TRUSTED;
 }
 
+static void ata_dev_config_cdl(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->link->ap;
+	unsigned int err_mask;
+	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))
+		goto not_supported;
+
+	err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
+				     ATA_LOG_SUPPORTED_CAPABILITIES,
+				     ap->sector_buf, 1);
+	if (err_mask)
+		goto not_supported;
+
+	/* Check Command Duration Limit Supported bits */
+	val = get_unaligned_le64(&ap->sector_buf[168]);
+	if (!(val & BIT_ULL(63)) || !(val & BIT_ULL(0)))
+		goto not_supported;
+
+	/* Warn the user if command duration guideline is not supported */
+	if (!(val & BIT_ULL(1)))
+		ata_dev_warn(dev,
+			"Command duration guideline is not supported\n");
+
+	/*
+	 * Command duration limits is supported: cache the CDL log page 18h
+	 * (command duration descriptors).
+	 */
+	err_mask = ata_read_log_page(dev, ATA_LOG_CDL, 0, ap->sector_buf, 1);
+	if (err_mask) {
+		ata_dev_warn(dev, "Read Command Duration Limits log failed\n");
+		goto not_supported;
+	}
+
+	memcpy(dev->cdl, ap->sector_buf, ATA_LOG_CDL_SIZE);
+	dev->flags |= ATA_DFLAG_CDL;
+
+	return;
+
+not_supported:
+	dev->flags &= ~ATA_DFLAG_CDL;
+}
+
 static int ata_dev_config_lba(struct ata_device *dev)
 {
 	const u16 *id = dev->id;
@@ -2534,13 +2582,14 @@ static void ata_dev_print_features(struct ata_device *dev)
 		return;
 
 	ata_dev_info(dev,
-		     "Features:%s%s%s%s%s%s%s\n",
+		     "Features:%s%s%s%s%s%s%s%s\n",
 		     dev->flags & ATA_DFLAG_FUA ? " FUA" : "",
 		     dev->flags & ATA_DFLAG_TRUSTED ? " Trust" : "",
 		     dev->flags & ATA_DFLAG_DA ? " Dev-Attention" : "",
 		     dev->flags & ATA_DFLAG_DEVSLP ? " Dev-Sleep" : "",
 		     dev->flags & ATA_DFLAG_NCQ_SEND_RECV ? " NCQ-sndrcv" : "",
 		     dev->flags & ATA_DFLAG_NCQ_PRIO ? " NCQ-prio" : "",
+		     dev->flags & ATA_DFLAG_CDL ? " CDL" : "",
 		     dev->cpr_log ? " CPR" : "");
 }
 
@@ -2702,6 +2751,7 @@ int ata_dev_configure(struct ata_device *dev)
 		ata_dev_config_zac(dev);
 		ata_dev_config_trusted(dev);
 		ata_dev_config_cpr(dev);
+		ata_dev_config_cdl(dev);
 		dev->cdb_len = 32;
 
 		if (print_info)