From 4658f79bec0b51222e769e328c2923f39f3bda77 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 22 Mar 2006 21:07:03 +0900 Subject: [PATCH] [PATCH] ahci: add softreset Now that libata is smart enought to handle both soft and hard resets, add softreset method. Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/scsi/ahci.c | 135 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 134 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c index a1ddbba2cbdf..ffba65656a83 100644 --- a/drivers/scsi/ahci.c +++ b/drivers/scsi/ahci.c @@ -513,6 +513,138 @@ static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, u32 opts) pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16); } +static int ahci_poll_register(void __iomem *reg, u32 mask, u32 val, + unsigned long interval_msec, + unsigned long timeout_msec) +{ + unsigned long timeout; + u32 tmp; + + timeout = jiffies + (timeout_msec * HZ) / 1000; + do { + tmp = readl(reg); + if ((tmp & mask) == val) + return 0; + msleep(interval_msec); + } while (time_before(jiffies, timeout)); + + return -1; +} + +static int ahci_softreset(struct ata_port *ap, int verbose, unsigned int *class) +{ + struct ahci_host_priv *hpriv = ap->host_set->private_data; + struct ahci_port_priv *pp = ap->private_data; + void __iomem *mmio = ap->host_set->mmio_base; + void __iomem *port_mmio = ahci_port_base(mmio, ap->port_no); + const u32 cmd_fis_len = 5; /* five dwords */ + const char *reason = NULL; + struct ata_taskfile tf; + u8 *fis; + int rc; + + DPRINTK("ENTER\n"); + + /* prepare for SRST (AHCI-1.1 10.4.1) */ + rc = ahci_stop_engine(ap); + if (rc) { + reason = "failed to stop engine"; + goto fail_restart; + } + + /* check BUSY/DRQ, perform Command List Override if necessary */ + ahci_tf_read(ap, &tf); + if (tf.command & (ATA_BUSY | ATA_DRQ)) { + u32 tmp; + + if (!(hpriv->cap & HOST_CAP_CLO)) { + rc = -EIO; + reason = "port busy but no CLO"; + goto fail_restart; + } + + tmp = readl(port_mmio + PORT_CMD); + tmp |= PORT_CMD_CLO; + writel(tmp, port_mmio + PORT_CMD); + readl(port_mmio + PORT_CMD); /* flush */ + + if (ahci_poll_register(port_mmio + PORT_CMD, PORT_CMD_CLO, 0x0, + 1, 500)) { + rc = -EIO; + reason = "CLO failed"; + goto fail_restart; + } + } + + /* restart engine */ + ahci_start_engine(ap); + + ata_tf_init(ap, &tf, 0); + fis = pp->cmd_tbl; + + /* issue the first D2H Register FIS */ + ahci_fill_cmd_slot(pp, cmd_fis_len | AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY); + + tf.ctl |= ATA_SRST; + ata_tf_to_fis(&tf, fis, 0); + fis[1] &= ~(1 << 7); /* turn off Command FIS bit */ + + writel(1, port_mmio + PORT_CMD_ISSUE); + readl(port_mmio + PORT_CMD_ISSUE); /* flush */ + + if (ahci_poll_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x0, 1, 500)) { + rc = -EIO; + reason = "1st FIS failed"; + goto fail; + } + + /* spec says at least 5us, but be generous and sleep for 1ms */ + msleep(1); + + /* issue the second D2H Register FIS */ + ahci_fill_cmd_slot(pp, cmd_fis_len); + + tf.ctl &= ~ATA_SRST; + ata_tf_to_fis(&tf, fis, 0); + fis[1] &= ~(1 << 7); /* turn off Command FIS bit */ + + writel(1, port_mmio + PORT_CMD_ISSUE); + readl(port_mmio + PORT_CMD_ISSUE); /* flush */ + + /* spec mandates ">= 2ms" before checking status. + * We wait 150ms, because that was the magic delay used for + * ATAPI devices in Hale Landis's ATADRVR, for the period of time + * between when the ATA command register is written, and then + * status is checked. Because waiting for "a while" before + * checking status is fine, post SRST, we perform this magic + * delay here as well. + */ + msleep(150); + + *class = ATA_DEV_NONE; + if (sata_dev_present(ap)) { + if (ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) { + rc = -EIO; + reason = "device not ready"; + goto fail; + } + *class = ahci_dev_classify(ap); + } + + DPRINTK("EXIT, class=%u\n", *class); + return 0; + + fail_restart: + ahci_start_engine(ap); + fail: + if (verbose) + printk(KERN_ERR "ata%u: softreset failed (%s)\n", + ap->id, reason); + else + DPRINTK("EXIT, rc=%d reason=\"%s\"\n", rc, reason); + return rc; +} + static int ahci_hardreset(struct ata_port *ap, int verbose, unsigned int *class) { int rc; @@ -553,7 +685,8 @@ static void ahci_postreset(struct ata_port *ap, unsigned int *class) static int ahci_probe_reset(struct ata_port *ap, unsigned int *classes) { - return ata_drive_probe_reset(ap, NULL, NULL, ahci_hardreset, + return ata_drive_probe_reset(ap, ata_std_probeinit, + ahci_softreset, ahci_hardreset, ahci_postreset, classes); }