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-rw-r--r--drivers/ata/libata-pmp.c1114
1 files changed, 1114 insertions, 0 deletions
diff --git a/drivers/ata/libata-pmp.c b/drivers/ata/libata-pmp.c
new file mode 100644
index 000000000..51eeaea65
--- /dev/null
+++ b/drivers/ata/libata-pmp.c
@@ -0,0 +1,1114 @@
+/*
+ * libata-pmp.c - libata port multiplier support
+ *
+ * Copyright (c) 2007 SUSE Linux Products GmbH
+ * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/libata.h>
+#include <linux/slab.h>
+#include "libata.h"
+#include "libata-transport.h"
+
+const struct ata_port_operations sata_pmp_port_ops = {
+ .inherits = &sata_port_ops,
+ .pmp_prereset = ata_std_prereset,
+ .pmp_hardreset = sata_std_hardreset,
+ .pmp_postreset = ata_std_postreset,
+ .error_handler = sata_pmp_error_handler,
+};
+
+/**
+ * sata_pmp_read - read PMP register
+ * @link: link to read PMP register for
+ * @reg: register to read
+ * @r_val: resulting value
+ *
+ * Read PMP register.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, AC_ERR_* mask on failure.
+ */
+static unsigned int sata_pmp_read(struct ata_link *link, int reg, u32 *r_val)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_device *pmp_dev = ap->link.device;
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+
+ ata_tf_init(pmp_dev, &tf);
+ tf.command = ATA_CMD_PMP_READ;
+ tf.protocol = ATA_PROT_NODATA;
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
+ tf.feature = reg;
+ tf.device = link->pmp;
+
+ err_mask = ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
+ SATA_PMP_RW_TIMEOUT);
+ if (err_mask)
+ return err_mask;
+
+ *r_val = tf.nsect | tf.lbal << 8 | tf.lbam << 16 | tf.lbah << 24;
+ return 0;
+}
+
+/**
+ * sata_pmp_write - write PMP register
+ * @link: link to write PMP register for
+ * @reg: register to write
+ * @r_val: value to write
+ *
+ * Write PMP register.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, AC_ERR_* mask on failure.
+ */
+static unsigned int sata_pmp_write(struct ata_link *link, int reg, u32 val)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_device *pmp_dev = ap->link.device;
+ struct ata_taskfile tf;
+
+ ata_tf_init(pmp_dev, &tf);
+ tf.command = ATA_CMD_PMP_WRITE;
+ tf.protocol = ATA_PROT_NODATA;
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
+ tf.feature = reg;
+ tf.device = link->pmp;
+ tf.nsect = val & 0xff;
+ tf.lbal = (val >> 8) & 0xff;
+ tf.lbam = (val >> 16) & 0xff;
+ tf.lbah = (val >> 24) & 0xff;
+
+ return ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
+ SATA_PMP_RW_TIMEOUT);
+}
+
+/**
+ * sata_pmp_qc_defer_cmd_switch - qc_defer for command switching PMP
+ * @qc: ATA command in question
+ *
+ * A host which has command switching PMP support cannot issue
+ * commands to multiple links simultaneously.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * ATA_DEFER_* if deferring is needed, 0 otherwise.
+ */
+int sata_pmp_qc_defer_cmd_switch(struct ata_queued_cmd *qc)
+{
+ struct ata_link *link = qc->dev->link;
+ struct ata_port *ap = link->ap;
+
+ if (ap->excl_link == NULL || ap->excl_link == link) {
+ if (ap->nr_active_links == 0 || ata_link_active(link)) {
+ qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
+ return ata_std_qc_defer(qc);
+ }
+
+ ap->excl_link = link;
+ }
+
+ return ATA_DEFER_PORT;
+}
+
+/**
+ * sata_pmp_scr_read - read PSCR
+ * @link: ATA link to read PSCR for
+ * @reg: PSCR to read
+ * @r_val: resulting value
+ *
+ * Read PSCR @reg into @r_val for @link, to be called from
+ * ata_scr_read().
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int sata_pmp_scr_read(struct ata_link *link, int reg, u32 *r_val)
+{
+ unsigned int err_mask;
+
+ if (reg > SATA_PMP_PSCR_CONTROL)
+ return -EINVAL;
+
+ err_mask = sata_pmp_read(link, reg, r_val);
+ if (err_mask) {
+ ata_link_warn(link, "failed to read SCR %d (Emask=0x%x)\n",
+ reg, err_mask);
+ return -EIO;
+ }
+ return 0;
+}
+
+/**
+ * sata_pmp_scr_write - write PSCR
+ * @link: ATA link to write PSCR for
+ * @reg: PSCR to write
+ * @val: value to be written
+ *
+ * Write @val to PSCR @reg for @link, to be called from
+ * ata_scr_write() and ata_scr_write_flush().
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int sata_pmp_scr_write(struct ata_link *link, int reg, u32 val)
+{
+ unsigned int err_mask;
+
+ if (reg > SATA_PMP_PSCR_CONTROL)
+ return -EINVAL;
+
+ err_mask = sata_pmp_write(link, reg, val);
+ if (err_mask) {
+ ata_link_warn(link, "failed to write SCR %d (Emask=0x%x)\n",
+ reg, err_mask);
+ return -EIO;
+ }
+ return 0;
+}
+
+/**
+ * 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
+ *
+ * Read selected PMP GSCRs from the PMP at @dev. This will serve
+ * as configuration and identification info for the PMP.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+static int sata_pmp_read_gscr(struct ata_device *dev, u32 *gscr)
+{
+ static const int gscr_to_read[] = { 0, 1, 2, 32, 33, 64, 96 };
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(gscr_to_read); i++) {
+ int reg = gscr_to_read[i];
+ unsigned int err_mask;
+
+ err_mask = sata_pmp_read(dev->link, reg, &gscr[reg]);
+ if (err_mask) {
+ ata_dev_err(dev, "failed to read PMP GSCR[%d] (Emask=0x%x)\n",
+ reg, err_mask);
+ return -EIO;
+ }
+ }
+
+ return 0;
+}
+
+static const char *sata_pmp_spec_rev_str(const u32 *gscr)
+{
+ u32 rev = gscr[SATA_PMP_GSCR_REV];
+
+ if (rev & (1 << 3))
+ return "1.2";
+ if (rev & (1 << 2))
+ return "1.1";
+ if (rev & (1 << 1))
+ return "1.0";
+ return "<unknown>";
+}
+
+#define PMP_GSCR_SII_POL 129
+
+static int sata_pmp_configure(struct ata_device *dev, int print_info)
+{
+ struct ata_port *ap = dev->link->ap;
+ u32 *gscr = dev->gscr;
+ u16 vendor = sata_pmp_gscr_vendor(gscr);
+ u16 devid = sata_pmp_gscr_devid(gscr);
+ unsigned int err_mask = 0;
+ const char *reason;
+ int nr_ports, rc;
+
+ nr_ports = sata_pmp_gscr_ports(gscr);
+
+ if (nr_ports <= 0 || nr_ports > SATA_PMP_MAX_PORTS) {
+ rc = -EINVAL;
+ reason = "invalid nr_ports";
+ goto fail;
+ }
+
+ if ((ap->flags & ATA_FLAG_AN) &&
+ (gscr[SATA_PMP_GSCR_FEAT] & SATA_PMP_FEAT_NOTIFY))
+ dev->flags |= ATA_DFLAG_AN;
+
+ /* monitor SERR_PHYRDY_CHG on fan-out ports */
+ err_mask = sata_pmp_write(dev->link, SATA_PMP_GSCR_ERROR_EN,
+ SERR_PHYRDY_CHG);
+ if (err_mask) {
+ rc = -EIO;
+ reason = "failed to write GSCR_ERROR_EN";
+ goto fail;
+ }
+
+ /* Disable sending Early R_OK.
+ * With "cached read" HDD testing and multiple ports busy on a SATA
+ * host controller, 3x26 PMP will very rarely drop a deferred
+ * R_OK that was intended for the host. Symptom will be all
+ * 5 drives under test will timeout, get reset, and recover.
+ */
+ if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
+ u32 reg;
+
+ err_mask = sata_pmp_read(&ap->link, PMP_GSCR_SII_POL, &reg);
+ if (err_mask) {
+ rc = -EIO;
+ reason = "failed to read Sil3x26 Private Register";
+ goto fail;
+ }
+ reg &= ~0x1;
+ err_mask = sata_pmp_write(&ap->link, PMP_GSCR_SII_POL, reg);
+ if (err_mask) {
+ rc = -EIO;
+ reason = "failed to write Sil3x26 Private Register";
+ goto fail;
+ }
+ }
+
+ if (print_info) {
+ ata_dev_info(dev, "Port Multiplier %s, "
+ "0x%04x:0x%04x r%d, %d ports, feat 0x%x/0x%x\n",
+ sata_pmp_spec_rev_str(gscr), vendor, devid,
+ sata_pmp_gscr_rev(gscr),
+ nr_ports, gscr[SATA_PMP_GSCR_FEAT_EN],
+ gscr[SATA_PMP_GSCR_FEAT]);
+
+ if (!(dev->flags & ATA_DFLAG_AN))
+ ata_dev_info(dev,
+ "Asynchronous notification not supported, "
+ "hotplug won't work on fan-out ports. Use warm-plug instead.\n");
+ }
+
+ return 0;
+
+ fail:
+ ata_dev_err(dev,
+ "failed to configure Port Multiplier (%s, Emask=0x%x)\n",
+ reason, err_mask);
+ return rc;
+}
+
+static int sata_pmp_init_links (struct ata_port *ap, int nr_ports)
+{
+ struct ata_link *pmp_link = ap->pmp_link;
+ int i, err;
+
+ if (!pmp_link) {
+ pmp_link = kcalloc(SATA_PMP_MAX_PORTS, sizeof(pmp_link[0]),
+ GFP_NOIO);
+ if (!pmp_link)
+ return -ENOMEM;
+
+ for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
+ ata_link_init(ap, &pmp_link[i], i);
+
+ ap->pmp_link = pmp_link;
+
+ for (i = 0; i < SATA_PMP_MAX_PORTS; i++) {
+ err = ata_tlink_add(&pmp_link[i]);
+ if (err) {
+ goto err_tlink;
+ }
+ }
+ }
+
+ for (i = 0; i < nr_ports; i++) {
+ struct ata_link *link = &pmp_link[i];
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ link->flags = 0;
+ ehc->i.probe_mask |= ATA_ALL_DEVICES;
+ ehc->i.action |= ATA_EH_RESET;
+ }
+
+ return 0;
+ err_tlink:
+ while (--i >= 0)
+ ata_tlink_delete(&pmp_link[i]);
+ kfree(pmp_link);
+ ap->pmp_link = NULL;
+ return err;
+}
+
+static void sata_pmp_quirks(struct ata_port *ap)
+{
+ u32 *gscr = ap->link.device->gscr;
+ u16 vendor = sata_pmp_gscr_vendor(gscr);
+ u16 devid = sata_pmp_gscr_devid(gscr);
+ struct ata_link *link;
+
+ if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
+ /* sil3x26 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.
+ */
+ if (link->pmp < 5)
+ link->flags |= ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_ATA;
+
+ /* port 5 is for SEMB device and it doesn't like SRST */
+ if (link->pmp == 5)
+ link->flags |= ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_SEMB;
+ }
+ } else if (vendor == 0x1095 && devid == 0x4723) {
+ /*
+ * sil4723 quirks
+ *
+ * Link reports offline after LPM. Class code report is
+ * unreliable. SIMG PMPs never got SRST reliable and the
+ * config device at port 2 locks up on SRST.
+ */
+ ata_for_each_link(link, ap, EDGE)
+ link->flags |= ATA_LFLAG_NO_LPM |
+ ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_ATA;
+ } 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
+ * locks up on SRST.
+ */
+ if (link->pmp <= 5)
+ link->flags |= ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_ATA;
+
+ /* Port 6 is for SEMB device which doesn't
+ * like SRST either.
+ */
+ if (link->pmp == 6)
+ link->flags |= ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_SEMB;
+ }
+ } else if (vendor == 0x1095 && (devid == 0x5723 || devid == 0x5733 ||
+ devid == 0x5734 || devid == 0x5744)) {
+ /* sil5723/5744 quirks */
+
+ /* sil5723/5744 has either two or three downstream
+ * ports depending on operation mode. The last port
+ * is empty if any actual IO device is available or
+ * occupied by a pseudo configuration device
+ * otherwise. Don't try hard to recover it.
+ */
+ ap->pmp_link[ap->nr_pmp_links - 1].flags |= ATA_LFLAG_NO_RETRY;
+ } else if (vendor == 0x197b && (devid == 0x2352 || devid == 0x0325)) {
+ /*
+ * 0x2352: found in Thermaltake BlackX Duet, jmicron JMB350?
+ * 0x0325: jmicron JMB394.
+ */
+ ata_for_each_link(link, ap, EDGE) {
+ /* SRST breaks detection and disks get misclassified
+ * LPM disabled to avoid potential problems
+ */
+ link->flags |= ATA_LFLAG_NO_LPM |
+ ATA_LFLAG_NO_SRST |
+ ATA_LFLAG_ASSUME_ATA;
+ }
+ } else if (vendor == 0x11ab && devid == 0x4140) {
+ /* Marvell 4140 quirks */
+ ata_for_each_link(link, ap, EDGE) {
+ /* port 4 is for SEMB device and it doesn't like SRST */
+ if (link->pmp == 4)
+ link->flags |= ATA_LFLAG_DISABLED;
+ }
+ }
+}
+
+/**
+ * sata_pmp_attach - attach a SATA PMP device
+ * @dev: SATA PMP device to attach
+ *
+ * Configure and attach SATA PMP device @dev. This function is
+ * also responsible for allocating and initializing PMP links.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int sata_pmp_attach(struct ata_device *dev)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ unsigned long flags;
+ struct ata_link *tlink;
+ int rc;
+
+ /* is it hanging off the right place? */
+ if (!sata_pmp_supported(ap)) {
+ ata_dev_err(dev, "host does not support Port Multiplier\n");
+ return -EINVAL;
+ }
+
+ if (!ata_is_host_link(link)) {
+ ata_dev_err(dev, "Port Multipliers cannot be nested\n");
+ return -EINVAL;
+ }
+
+ if (dev->devno) {
+ ata_dev_err(dev, "Port Multiplier must be the first device\n");
+ return -EINVAL;
+ }
+
+ WARN_ON(link->pmp != 0);
+ link->pmp = SATA_PMP_CTRL_PORT;
+
+ /* read GSCR block */
+ rc = sata_pmp_read_gscr(dev, dev->gscr);
+ if (rc)
+ goto fail;
+
+ /* config PMP */
+ rc = sata_pmp_configure(dev, 1);
+ if (rc)
+ goto fail;
+
+ rc = sata_pmp_init_links(ap, sata_pmp_gscr_ports(dev->gscr));
+ if (rc) {
+ ata_dev_info(dev, "failed to initialize PMP links\n");
+ goto fail;
+ }
+
+ /* attach it */
+ spin_lock_irqsave(ap->lock, flags);
+ WARN_ON(ap->nr_pmp_links);
+ ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ sata_pmp_quirks(ap);
+
+ if (ap->ops->pmp_attach)
+ ap->ops->pmp_attach(ap);
+
+ ata_for_each_link(tlink, ap, EDGE)
+ sata_link_init_spd(tlink);
+
+ return 0;
+
+ fail:
+ link->pmp = 0;
+ return rc;
+}
+
+/**
+ * sata_pmp_detach - detach a SATA PMP device
+ * @dev: SATA PMP device to detach
+ *
+ * Detach SATA PMP device @dev. This function is also
+ * responsible for deconfiguring PMP links.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ */
+static void sata_pmp_detach(struct ata_device *dev)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ struct ata_link *tlink;
+ unsigned long flags;
+
+ ata_dev_info(dev, "Port Multiplier detaching\n");
+
+ WARN_ON(!ata_is_host_link(link) || dev->devno ||
+ link->pmp != SATA_PMP_CTRL_PORT);
+
+ if (ap->ops->pmp_detach)
+ ap->ops->pmp_detach(ap);
+
+ ata_for_each_link(tlink, ap, EDGE)
+ ata_eh_detach_dev(tlink->device);
+
+ spin_lock_irqsave(ap->lock, flags);
+ ap->nr_pmp_links = 0;
+ link->pmp = 0;
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+
+/**
+ * sata_pmp_same_pmp - does new GSCR matches the configured PMP?
+ * @dev: PMP device to compare against
+ * @new_gscr: GSCR block of the new device
+ *
+ * Compare @new_gscr against @dev and determine whether @dev is
+ * the PMP described by @new_gscr.
+ *
+ * LOCKING:
+ * None.
+ *
+ * RETURNS:
+ * 1 if @dev matches @new_gscr, 0 otherwise.
+ */
+static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
+{
+ const u32 *old_gscr = dev->gscr;
+ u16 old_vendor, new_vendor, old_devid, new_devid;
+ int old_nr_ports, new_nr_ports;
+
+ old_vendor = sata_pmp_gscr_vendor(old_gscr);
+ new_vendor = sata_pmp_gscr_vendor(new_gscr);
+ old_devid = sata_pmp_gscr_devid(old_gscr);
+ new_devid = sata_pmp_gscr_devid(new_gscr);
+ old_nr_ports = sata_pmp_gscr_ports(old_gscr);
+ new_nr_ports = sata_pmp_gscr_ports(new_gscr);
+
+ if (old_vendor != new_vendor) {
+ ata_dev_info(dev,
+ "Port Multiplier vendor mismatch '0x%x' != '0x%x'\n",
+ old_vendor, new_vendor);
+ return 0;
+ }
+
+ if (old_devid != new_devid) {
+ ata_dev_info(dev,
+ "Port Multiplier device ID mismatch '0x%x' != '0x%x'\n",
+ old_devid, new_devid);
+ return 0;
+ }
+
+ if (old_nr_ports != new_nr_ports) {
+ ata_dev_info(dev,
+ "Port Multiplier nr_ports mismatch '0x%x' != '0x%x'\n",
+ old_nr_ports, new_nr_ports);
+ return 0;
+ }
+
+ return 1;
+}
+
+/**
+ * sata_pmp_revalidate - revalidate SATA PMP
+ * @dev: PMP device to revalidate
+ * @new_class: new class code
+ *
+ * Re-read GSCR block and make sure @dev is still attached to the
+ * port and properly configured.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno otherwise.
+ */
+static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ u32 *gscr = (void *)ap->sector_buf;
+ int rc;
+
+ DPRINTK("ENTER\n");
+
+ ata_eh_about_to_do(link, NULL, ATA_EH_REVALIDATE);
+
+ if (!ata_dev_enabled(dev)) {
+ rc = -ENODEV;
+ goto fail;
+ }
+
+ /* wrong class? */
+ if (ata_class_enabled(new_class) && new_class != ATA_DEV_PMP) {
+ rc = -ENODEV;
+ goto fail;
+ }
+
+ /* read GSCR */
+ rc = sata_pmp_read_gscr(dev, gscr);
+ if (rc)
+ goto fail;
+
+ /* is the pmp still there? */
+ if (!sata_pmp_same_pmp(dev, gscr)) {
+ rc = -ENODEV;
+ goto fail;
+ }
+
+ memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);
+
+ rc = sata_pmp_configure(dev, 0);
+ if (rc)
+ goto fail;
+
+ ata_eh_done(link, NULL, ATA_EH_REVALIDATE);
+
+ DPRINTK("EXIT, rc=0\n");
+ return 0;
+
+ fail:
+ ata_dev_err(dev, "PMP revalidation failed (errno=%d)\n", rc);
+ DPRINTK("EXIT, rc=%d\n", rc);
+ return rc;
+}
+
+/**
+ * sata_pmp_revalidate_quick - revalidate SATA PMP quickly
+ * @dev: PMP device to revalidate
+ *
+ * Make sure the attached PMP is accessible.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno otherwise.
+ */
+static int sata_pmp_revalidate_quick(struct ata_device *dev)
+{
+ unsigned int err_mask;
+ u32 prod_id;
+
+ err_mask = sata_pmp_read(dev->link, SATA_PMP_GSCR_PROD_ID, &prod_id);
+ if (err_mask) {
+ ata_dev_err(dev,
+ "failed to read PMP product ID (Emask=0x%x)\n",
+ err_mask);
+ return -EIO;
+ }
+
+ if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
+ ata_dev_err(dev, "PMP product ID mismatch\n");
+ /* something weird is going on, request full PMP recovery */
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * sata_pmp_eh_recover_pmp - recover PMP
+ * @ap: ATA port PMP is attached to
+ * @prereset: prereset method (can be NULL)
+ * @softreset: softreset method
+ * @hardreset: hardreset method
+ * @postreset: postreset method (can be NULL)
+ *
+ * Recover PMP attached to @ap. Recovery procedure is somewhat
+ * similar to that of ata_eh_recover() except that reset should
+ * always be performed in hard->soft sequence and recovery
+ * failure results in PMP detachment.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
+ ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
+ ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
+{
+ struct ata_link *link = &ap->link;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev = link->device;
+ int tries = ATA_EH_PMP_TRIES;
+ int detach = 0, rc = 0;
+ int reval_failed = 0;
+
+ DPRINTK("ENTER\n");
+
+ if (dev->flags & ATA_DFLAG_DETACH) {
+ detach = 1;
+ rc = -ENODEV;
+ goto fail;
+ }
+
+ retry:
+ ehc->classes[0] = ATA_DEV_UNKNOWN;
+
+ if (ehc->i.action & ATA_EH_RESET) {
+ struct ata_link *tlink;
+
+ /* reset */
+ rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
+ postreset);
+ if (rc) {
+ ata_link_err(link, "failed to reset PMP, giving up\n");
+ goto fail;
+ }
+
+ /* PMP is reset, SErrors cannot be trusted, scan all */
+ ata_for_each_link(tlink, ap, EDGE) {
+ struct ata_eh_context *ehc = &tlink->eh_context;
+
+ ehc->i.probe_mask |= ATA_ALL_DEVICES;
+ ehc->i.action |= ATA_EH_RESET;
+ }
+ }
+
+ /* If revalidation is requested, revalidate and reconfigure;
+ * otherwise, do quick revalidation.
+ */
+ if (ehc->i.action & ATA_EH_REVALIDATE)
+ rc = sata_pmp_revalidate(dev, ehc->classes[0]);
+ else
+ rc = sata_pmp_revalidate_quick(dev);
+
+ if (rc) {
+ tries--;
+
+ if (rc == -ENODEV) {
+ ehc->i.probe_mask |= ATA_ALL_DEVICES;
+ detach = 1;
+ /* give it just two more chances */
+ tries = min(tries, 2);
+ }
+
+ if (tries) {
+ /* consecutive revalidation failures? speed down */
+ if (reval_failed)
+ sata_down_spd_limit(link, 0);
+ else
+ reval_failed = 1;
+
+ ehc->i.action |= ATA_EH_RESET;
+ goto retry;
+ } else {
+ ata_dev_err(dev,
+ "failed to recover PMP after %d tries, giving up\n",
+ ATA_EH_PMP_TRIES);
+ goto fail;
+ }
+ }
+
+ /* okay, PMP resurrected */
+ ehc->i.flags = 0;
+
+ DPRINTK("EXIT, rc=0\n");
+ return 0;
+
+ fail:
+ sata_pmp_detach(dev);
+ if (detach)
+ ata_eh_detach_dev(dev);
+ else
+ ata_dev_disable(dev);
+
+ DPRINTK("EXIT, rc=%d\n", rc);
+ return rc;
+}
+
+static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
+{
+ struct ata_link *link;
+ unsigned long flags;
+ int rc;
+
+ spin_lock_irqsave(ap->lock, flags);
+
+ ata_for_each_link(link, ap, EDGE) {
+ if (!(link->flags & ATA_LFLAG_DISABLED))
+ continue;
+
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ /* Some PMPs require hardreset sequence to get
+ * SError.N working.
+ */
+ sata_link_hardreset(link, sata_deb_timing_normal,
+ ata_deadline(jiffies, ATA_TMOUT_INTERNAL_QUICK),
+ NULL, NULL);
+
+ /* unconditionally clear SError.N */
+ rc = sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
+ if (rc) {
+ ata_link_err(link,
+ "failed to clear SError.N (errno=%d)\n",
+ rc);
+ return rc;
+ }
+
+ spin_lock_irqsave(ap->lock, flags);
+ }
+
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return 0;
+}
+
+static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
+{
+ struct ata_port *ap = link->ap;
+ unsigned long flags;
+
+ if (link_tries[link->pmp] && --link_tries[link->pmp])
+ return 1;
+
+ /* disable this link */
+ if (!(link->flags & ATA_LFLAG_DISABLED)) {
+ ata_link_warn(link,
+ "failed to recover link after %d tries, disabling\n",
+ ATA_EH_PMP_LINK_TRIES);
+
+ spin_lock_irqsave(ap->lock, flags);
+ link->flags |= ATA_LFLAG_DISABLED;
+ spin_unlock_irqrestore(ap->lock, flags);
+ }
+
+ ata_dev_disable(link->device);
+ link->eh_context.i.action = 0;
+
+ return 0;
+}
+
+/**
+ * sata_pmp_eh_recover - recover PMP-enabled port
+ * @ap: ATA port to recover
+ *
+ * Drive EH recovery operation for PMP enabled port @ap. This
+ * function recovers host and PMP ports with proper retrials and
+ * fallbacks. Actual recovery operations are performed using
+ * ata_eh_recover() and sata_pmp_eh_recover_pmp().
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+static int sata_pmp_eh_recover(struct ata_port *ap)
+{
+ struct ata_port_operations *ops = ap->ops;
+ int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
+ struct ata_link *pmp_link = &ap->link;
+ struct ata_device *pmp_dev = pmp_link->device;
+ struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
+ u32 *gscr = pmp_dev->gscr;
+ struct ata_link *link;
+ struct ata_device *dev;
+ unsigned int err_mask;
+ u32 gscr_error, sntf;
+ int cnt, rc;
+
+ pmp_tries = ATA_EH_PMP_TRIES;
+ ata_for_each_link(link, ap, EDGE)
+ link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
+
+ retry:
+ /* PMP attached? */
+ if (!sata_pmp_attached(ap)) {
+ rc = ata_eh_recover(ap, ops->prereset, ops->softreset,
+ ops->hardreset, ops->postreset, NULL);
+ if (rc) {
+ ata_for_each_dev(dev, &ap->link, ALL)
+ ata_dev_disable(dev);
+ return rc;
+ }
+
+ if (pmp_dev->class != ATA_DEV_PMP)
+ return 0;
+
+ /* new PMP online */
+ ata_for_each_link(link, ap, EDGE)
+ link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
+
+ /* fall through */
+ }
+
+ /* recover pmp */
+ rc = sata_pmp_eh_recover_pmp(ap, ops->prereset, ops->softreset,
+ ops->hardreset, ops->postreset);
+ if (rc)
+ goto pmp_fail;
+
+ /* PHY event notification can disturb reset and other recovery
+ * operations. Turn it off.
+ */
+ if (gscr[SATA_PMP_GSCR_FEAT_EN] & SATA_PMP_FEAT_NOTIFY) {
+ gscr[SATA_PMP_GSCR_FEAT_EN] &= ~SATA_PMP_FEAT_NOTIFY;
+
+ err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
+ gscr[SATA_PMP_GSCR_FEAT_EN]);
+ if (err_mask) {
+ ata_link_warn(pmp_link,
+ "failed to disable NOTIFY (err_mask=0x%x)\n",
+ err_mask);
+ goto pmp_fail;
+ }
+ }
+
+ /* handle disabled links */
+ rc = sata_pmp_eh_handle_disabled_links(ap);
+ if (rc)
+ goto pmp_fail;
+
+ /* recover links */
+ rc = ata_eh_recover(ap, ops->pmp_prereset, ops->pmp_softreset,
+ ops->pmp_hardreset, ops->pmp_postreset, &link);
+ if (rc)
+ goto link_fail;
+
+ /* 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;
+
+ err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
+ gscr[SATA_PMP_GSCR_FEAT_EN]);
+ if (err_mask) {
+ ata_dev_err(pmp_dev,
+ "failed to write PMP_FEAT_EN (Emask=0x%x)\n",
+ err_mask);
+ rc = -EIO;
+ goto pmp_fail;
+ }
+ }
+
+ /* check GSCR_ERROR */
+ err_mask = sata_pmp_read(pmp_link, SATA_PMP_GSCR_ERROR, &gscr_error);
+ if (err_mask) {
+ ata_dev_err(pmp_dev,
+ "failed to read PMP_GSCR_ERROR (Emask=0x%x)\n",
+ err_mask);
+ rc = -EIO;
+ goto pmp_fail;
+ }
+
+ cnt = 0;
+ ata_for_each_link(link, ap, EDGE) {
+ if (!(gscr_error & (1 << link->pmp)))
+ continue;
+
+ if (sata_pmp_handle_link_fail(link, link_tries)) {
+ ata_ehi_hotplugged(&link->eh_context.i);
+ cnt++;
+ } else {
+ ata_link_warn(link,
+ "PHY status changed but maxed out on retries, giving up\n");
+ ata_link_warn(link,
+ "Manually issue scan to resume this link\n");
+ }
+ }
+
+ if (cnt) {
+ ata_port_info(ap,
+ "PMP SError.N set for some ports, repeating recovery\n");
+ goto retry;
+ }
+
+ return 0;
+
+ link_fail:
+ if (sata_pmp_handle_link_fail(link, link_tries)) {
+ pmp_ehc->i.action |= ATA_EH_RESET;
+ goto retry;
+ }
+
+ /* fall through */
+ pmp_fail:
+ /* Control always ends up here after detaching PMP. Shut up
+ * and return if we're unloading.
+ */
+ if (ap->pflags & ATA_PFLAG_UNLOADING)
+ return rc;
+
+ if (!sata_pmp_attached(ap))
+ goto retry;
+
+ if (--pmp_tries) {
+ pmp_ehc->i.action |= ATA_EH_RESET;
+ goto retry;
+ }
+
+ ata_port_err(ap, "failed to recover PMP after %d tries, giving up\n",
+ ATA_EH_PMP_TRIES);
+ sata_pmp_detach(pmp_dev);
+ ata_dev_disable(pmp_dev);
+
+ return rc;
+}
+
+/**
+ * sata_pmp_error_handler - do standard error handling for PMP-enabled host
+ * @ap: host port to handle error for
+ *
+ * Perform standard error handling sequence for PMP-enabled host
+ * @ap.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ */
+void sata_pmp_error_handler(struct ata_port *ap)
+{
+ ata_eh_autopsy(ap);
+ ata_eh_report(ap);
+ sata_pmp_eh_recover(ap);
+ ata_eh_finish(ap);
+}
+
+EXPORT_SYMBOL_GPL(sata_pmp_port_ops);
+EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
+EXPORT_SYMBOL_GPL(sata_pmp_error_handler);