libata: implement LPM support for port multipliers
Port multipliers can do DIPM on fan-out links fine. Implement support
for it. Tested w/ SIMG 57xx and marvell PMPs. Both the host and
fan-out links enter power save modes nicely.
SIMG 37xx and 47xx report link offline on SStatus causing EH to detach
the devices. Blacklisted.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-pmp.c b/drivers/ata/libata-pmp.c
index 5054702..3120596 100644
--- a/drivers/ata/libata-pmp.c
+++ b/drivers/ata/libata-pmp.c
@@ -186,6 +186,27 @@
}
/**
+ * sata_pmp_set_lpm - configure LPM for a PMP link
+ * @link: PMP link to configure LPM for
+ * @policy: target LPM policy
+ * @hints: LPM hints
+ *
+ * Configure LPM for @link. This function will contain any PMP
+ * specific workarounds if necessary.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int sata_pmp_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
+ unsigned hints)
+{
+ return sata_link_scr_lpm(link, policy, true);
+}
+
+/**
* sata_pmp_read_gscr - read GSCR block of SATA PMP
* @dev: PMP device
* @gscr: buffer to read GSCR block into
@@ -365,6 +386,9 @@
if (vendor == 0x1095 && devid == 0x3726) {
/* sil3726 quirks */
ata_for_each_link(link, ap, EDGE) {
+ /* link reports offline after LPM */
+ link->flags |= ATA_LFLAG_NO_LPM;
+
/* Class code report is unreliable and SRST
* times out under certain configurations.
*/
@@ -380,6 +404,9 @@
} else if (vendor == 0x1095 && devid == 0x4723) {
/* sil4723 quirks */
ata_for_each_link(link, ap, EDGE) {
+ /* link reports offline after LPM */
+ link->flags |= ATA_LFLAG_NO_LPM;
+
/* class code report is unreliable */
if (link->pmp < 2)
link->flags |= ATA_LFLAG_ASSUME_ATA;
@@ -392,6 +419,9 @@
} else if (vendor == 0x1095 && devid == 0x4726) {
/* sil4726 quirks */
ata_for_each_link(link, ap, EDGE) {
+ /* link reports offline after LPM */
+ link->flags |= ATA_LFLAG_NO_LPM;
+
/* Class code report is unreliable and SRST
* times out under certain configurations.
* Config device can be at port 0 or 5 and
@@ -952,15 +982,25 @@
if (rc)
goto link_fail;
- /* Connection status might have changed while resetting other
- * links, check SATA_PMP_GSCR_ERROR before returning.
- */
-
/* clear SNotification */
rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
if (rc == 0)
sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
+ /*
+ * If LPM is active on any fan-out port, hotplug wouldn't
+ * work. Return w/ PHY event notification disabled.
+ */
+ ata_for_each_link(link, ap, EDGE)
+ if (link->lpm_policy > ATA_LPM_MAX_POWER)
+ return 0;
+
+ /*
+ * Connection status might have changed while resetting other
+ * links, enable notification and check SATA_PMP_GSCR_ERROR
+ * before returning.
+ */
+
/* enable notification */
if (pmp_dev->flags & ATA_DFLAG_AN) {
gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;