diff options
| -rw-r--r-- | drivers/scsi/libata-core.c | 143 | ||||
| -rw-r--r-- | include/linux/libata.h | 1 |
2 files changed, 140 insertions, 4 deletions
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 3acf56200d87..63488673765f 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -65,6 +65,7 @@ static unsigned int ata_dev_init_params(struct ata_port *ap, struct ata_device *dev, u16 heads, u16 sectors); +static int ata_down_sata_spd_limit(struct ata_port *ap); static int ata_set_mode(struct ata_port *ap, struct ata_device **r_failed_dev); static unsigned int ata_dev_set_xfermode(struct ata_port *ap, struct ata_device *dev); @@ -1596,6 +1597,120 @@ void ata_port_disable(struct ata_port *ap) ap->flags |= ATA_FLAG_PORT_DISABLED; } +/** + * ata_down_sata_spd_limit - adjust SATA spd limit downward + * @ap: Port to adjust SATA spd limit for + * + * Adjust SATA spd limit of @ap downward. Note that this + * function only adjusts the limit. The change must be applied + * using ata_set_sata_spd(). + * + * LOCKING: + * Inherited from caller. + * + * RETURNS: + * 0 on success, negative errno on failure + */ +static int ata_down_sata_spd_limit(struct ata_port *ap) +{ + u32 spd, mask; + int highbit; + + if (ap->cbl != ATA_CBL_SATA || !ap->ops->scr_read) + return -EOPNOTSUPP; + + mask = ap->sata_spd_limit; + if (mask <= 1) + return -EINVAL; + highbit = fls(mask) - 1; + mask &= ~(1 << highbit); + + spd = (scr_read(ap, SCR_STATUS) >> 4) & 0xf; + if (spd <= 1) + return -EINVAL; + spd--; + mask &= (1 << spd) - 1; + if (!mask) + return -EINVAL; + + ap->sata_spd_limit = mask; + + printk(KERN_WARNING "ata%u: limiting SATA link speed to %s\n", + ap->id, sata_spd_string(fls(mask))); + + return 0; +} + +static int __ata_set_sata_spd_needed(struct ata_port *ap, u32 *scontrol) +{ + u32 spd, limit; + + if (ap->sata_spd_limit == UINT_MAX) + limit = 0; + else + limit = fls(ap->sata_spd_limit); + + spd = (*scontrol >> 4) & 0xf; + *scontrol = (*scontrol & ~0xf0) | ((limit & 0xf) << 4); + + return spd != limit; +} + +/** + * ata_set_sata_spd_needed - is SATA spd configuration needed + * @ap: Port in question + * + * Test whether the spd limit in SControl matches + * @ap->sata_spd_limit. This function is used to determine + * whether hardreset is necessary to apply SATA spd + * configuration. + * + * LOCKING: + * Inherited from caller. + * + * RETURNS: + * 1 if SATA spd configuration is needed, 0 otherwise. + */ +static int ata_set_sata_spd_needed(struct ata_port *ap) +{ + u32 scontrol; + + if (ap->cbl != ATA_CBL_SATA || !ap->ops->scr_read) + return 0; + + scontrol = scr_read(ap, SCR_CONTROL); + + return __ata_set_sata_spd_needed(ap, &scontrol); +} + +/** + * ata_set_sata_spd - set SATA spd according to spd limit + * @ap: Port to set SATA spd for + * + * Set SATA spd of @ap according to sata_spd_limit. + * + * LOCKING: + * Inherited from caller. + * + * RETURNS: + * 0 if spd doesn't need to be changed, 1 if spd has been + * changed. -EOPNOTSUPP if SCR registers are inaccessible. + */ +static int ata_set_sata_spd(struct ata_port *ap) +{ + u32 scontrol; + + if (ap->cbl != ATA_CBL_SATA || !ap->ops->scr_read) + return -EOPNOTSUPP; + + scontrol = scr_read(ap, SCR_CONTROL); + if (!__ata_set_sata_spd_needed(ap, &scontrol)) + return 0; + + scr_write(ap, SCR_CONTROL, scontrol); + return 1; +} + /* * This mode timing computation functionality is ported over from * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik @@ -2165,7 +2280,14 @@ static int sata_phy_resume(struct ata_port *ap) void ata_std_probeinit(struct ata_port *ap) { if ((ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read) { + u32 spd; + sata_phy_resume(ap); + + spd = (scr_read(ap, SCR_CONTROL) & 0xf0) >> 4; + if (spd) + ap->sata_spd_limit &= (1 << spd) - 1; + if (sata_dev_present(ap)) ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT); } @@ -2253,18 +2375,30 @@ int sata_std_hardreset(struct ata_port *ap, int verbose, unsigned int *class) DPRINTK("ENTER\n"); - /* Issue phy wake/reset */ + if (ata_set_sata_spd_needed(ap)) { + /* SATA spec says nothing about how to reconfigure + * spd. To be on the safe side, turn off phy during + * reconfiguration. This works for at least ICH7 AHCI + * and Sil3124. + */ + scontrol = scr_read(ap, SCR_CONTROL); + scontrol = (scontrol & 0x0f0) | 0x302; + scr_write_flush(ap, SCR_CONTROL, scontrol); + + ata_set_sata_spd(ap); + } + + /* issue phy wake/reset */ scontrol = scr_read(ap, SCR_CONTROL); scontrol = (scontrol & 0x0f0) | 0x301; scr_write_flush(ap, SCR_CONTROL, scontrol); - /* - * Couldn't find anything in SATA I/II specs, but AHCI-1.1 + /* Couldn't find anything in SATA I/II specs, but AHCI-1.1 * 10.4.2 says at least 1 ms. */ msleep(1); - /* Bring phy back */ + /* bring phy back */ sata_phy_resume(ap); /* TODO: phy layer with polling, timeouts, etc. */ @@ -4454,6 +4588,7 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host, ap->flags |= ent->host_flags; ap->ops = ent->port_ops; ap->cbl = ATA_CBL_NONE; + ap->sata_spd_limit = UINT_MAX; ap->active_tag = ATA_TAG_POISON; ap->last_ctl = 0xFF; diff --git a/include/linux/libata.h b/include/linux/libata.h index 0f8e3720edd9..a5207e66ca52 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -397,6 +397,7 @@ struct ata_port { unsigned int mwdma_mask; unsigned int udma_mask; unsigned int cbl; /* cable type; ATA_CBL_xxx */ + unsigned int sata_spd_limit; /* SATA PHY speed limit */ struct ata_device device[ATA_MAX_DEVICES]; |