[PATCH 3.12 33/72] ahci: avoton port-disable reset-quirk

From: Jiri Slaby
Date: Mon Nov 23 2015 - 08:21:55 EST

From: Dan Williams <dan.j.williams@xxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit dbfe8ef5599a5370abc441fcdbb382b656563eb4 upstream.

Avoton AHCI occasionally sees drive probe timeouts at driver load time.
When this happens SCR_STATUS indicates device detected, but no D2H FIS
reception. Reset the internal link state machines by bouncing
port-enable in the PCS register when this occurs.

Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/ata/ahci.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 95 insertions(+), 8 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 548bf80a70e3..f354867a3b95 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -67,6 +67,7 @@ enum board_ids {
board_ahci_yes_fbs,

/* board IDs for specific chipsets in alphabetical order */
+ board_ahci_avn,
board_ahci_mcp65,
board_ahci_mcp77,
board_ahci_mcp89,
@@ -85,6 +86,8 @@ enum board_ids {
static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
+static int ahci_avn_hardreset(struct ata_link *link, unsigned int *class,
+ unsigned long deadline);
static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
#ifdef CONFIG_PM
@@ -106,6 +109,11 @@ static struct ata_port_operations ahci_p5wdh_ops = {
.hardreset = ahci_p5wdh_hardreset,
};

+static struct ata_port_operations ahci_avn_ops = {
+ .inherits = &ahci_ops,
+ .hardreset = ahci_avn_hardreset,
+};
+
static const struct ata_port_info ahci_port_info[] = {
/* by features */
[board_ahci] = {
@@ -150,6 +158,12 @@ static const struct ata_port_info ahci_port_info[] = {
.port_ops = &ahci_ops,
},
/* by chipsets */
+ [board_ahci_avn] = {
+ .flags = AHCI_FLAG_COMMON,
+ .pio_mask = ATA_PIO4,
+ .udma_mask = ATA_UDMA6,
+ .port_ops = &ahci_avn_ops,
+ },
[board_ahci_mcp65] = {
AHCI_HFLAGS (AHCI_HFLAG_NO_FPDMA_AA | AHCI_HFLAG_NO_PMP |
AHCI_HFLAG_YES_NCQ),
@@ -289,14 +303,14 @@ static const struct pci_device_id ahci_pci_tbl[] = {
{ PCI_VDEVICE(INTEL, 0x1f27), board_ahci }, /* Avoton RAID */
{ PCI_VDEVICE(INTEL, 0x1f2e), board_ahci }, /* Avoton RAID */
{ PCI_VDEVICE(INTEL, 0x1f2f), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f32), board_ahci }, /* Avoton AHCI */
- { PCI_VDEVICE(INTEL, 0x1f33), board_ahci }, /* Avoton AHCI */
- { PCI_VDEVICE(INTEL, 0x1f34), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f35), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f36), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f37), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f3e), board_ahci }, /* Avoton RAID */
- { PCI_VDEVICE(INTEL, 0x1f3f), board_ahci }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f32), board_ahci_avn }, /* Avoton AHCI */
+ { PCI_VDEVICE(INTEL, 0x1f33), board_ahci_avn }, /* Avoton AHCI */
+ { PCI_VDEVICE(INTEL, 0x1f34), board_ahci_avn }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f35), board_ahci_avn }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f36), board_ahci_avn }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f37), board_ahci_avn }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f3e), board_ahci_avn }, /* Avoton RAID */
+ { PCI_VDEVICE(INTEL, 0x1f3f), board_ahci_avn }, /* Avoton RAID */
{ PCI_VDEVICE(INTEL, 0x2823), board_ahci }, /* Wellsburg RAID */
{ PCI_VDEVICE(INTEL, 0x2827), board_ahci }, /* Wellsburg RAID */
{ PCI_VDEVICE(INTEL, 0x8d02), board_ahci }, /* Wellsburg AHCI */
@@ -674,6 +688,79 @@ static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
return rc;
}

+/*
+ * ahci_avn_hardreset - attempt more aggressive recovery of Avoton ports.
+ *
+ * It has been observed with some SSDs that the timing of events in the
+ * link synchronization phase can leave the port in a state that can not
+ * be recovered by a SATA-hard-reset alone. The failing signature is
+ * SStatus.DET stuck at 1 ("Device presence detected but Phy
+ * communication not established"). It was found that unloading and
+ * reloading the driver when this problem occurs allows the drive
+ * connection to be recovered (DET advanced to 0x3). The critical
+ * component of reloading the driver is that the port state machines are
+ * reset by bouncing "port enable" in the AHCI PCS configuration
+ * register. So, reproduce that effect by bouncing a port whenever we
+ * see DET==1 after a reset.
+ */
+static int ahci_avn_hardreset(struct ata_link *link, unsigned int *class,
+ unsigned long deadline)
+{
+ const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
+ struct ata_port *ap = link->ap;
+ struct ahci_port_priv *pp = ap->private_data;
+ struct ahci_host_priv *hpriv = ap->host->private_data;
+ u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+ unsigned long tmo = deadline - jiffies;
+ struct ata_taskfile tf;
+ bool online;
+ int rc, i;
+
+ DPRINTK("ENTER\n");
+
+ ahci_stop_engine(ap);
+
+ for (i = 0; i < 2; i++) {
+ u16 val;
+ u32 sstatus;
+ int port = ap->port_no;
+ struct ata_host *host = ap->host;
+ struct pci_dev *pdev = to_pci_dev(host->dev);
+
+ /* clear D2H reception area to properly wait for D2H FIS */
+ ata_tf_init(link->device, &tf);
+ tf.command = ATA_BUSY;
+ ata_tf_to_fis(&tf, 0, 0, d2h_fis);
+
+ rc = sata_link_hardreset(link, timing, deadline, &online,
+ ahci_check_ready);
+
+ if (sata_scr_read(link, SCR_STATUS, &sstatus) != 0 ||
+ (sstatus & 0xf) != 1)
+ break;
+
+ ata_link_printk(link, KERN_INFO, "avn bounce port%d\n",
+ port);
+
+ pci_read_config_word(pdev, 0x92, &val);
+ val &= ~(1 << port);
+ pci_write_config_word(pdev, 0x92, val);
+ ata_msleep(ap, 1000);
+ val |= 1 << port;
+ pci_write_config_word(pdev, 0x92, val);
+ deadline += tmo;
+ }
+
+ hpriv->start_engine(ap);
+
+ if (online)
+ *class = ahci_dev_classify(ap);
+
+ DPRINTK("EXIT, rc=%d, class=%u\n", rc, *class);
+ return rc;
+}
+
+
#ifdef CONFIG_PM
static int ahci_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
{
--
2.6.3

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