diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index a9f79b47b4c3..4823ecefb8a1 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -61,6 +61,11 @@ #include "libata.h" +/* debounce timing parameters in msecs { interval, duration, timeout } */ +const unsigned long sata_deb_timing_boot[] = { 5, 100, 2000 }; +const unsigned long sata_deb_timing_eh[] = { 25, 500, 2000 }; +const unsigned long sata_deb_timing_before_fsrst[] = { 100, 2000, 5000 }; + static unsigned int ata_dev_init_params(struct ata_device *dev, u16 heads, u16 sectors); static unsigned int ata_dev_set_xfermode(struct ata_device *dev); @@ -2427,10 +2432,81 @@ err_out: DPRINTK("EXIT\n"); } -static int sata_phy_resume(struct ata_port *ap) +/** + * sata_phy_debounce - debounce SATA phy status + * @ap: ATA port to debounce SATA phy status for + * @params: timing parameters { interval, duratinon, timeout } in msec + * + * Make sure SStatus of @ap reaches stable state, determined by + * holding the same value where DET is not 1 for @duration polled + * every @interval, before @timeout. Timeout constraints the + * beginning of the stable state. Because, after hot unplugging, + * DET gets stuck at 1 on some controllers, this functions waits + * until timeout then returns 0 if DET is stable at 1. + * + * LOCKING: + * Kernel thread context (may sleep) + * + * RETURNS: + * 0 on success, -errno on failure. + */ +int sata_phy_debounce(struct ata_port *ap, const unsigned long *params) { - unsigned long timeout = jiffies + (HZ * 5); - u32 scontrol, sstatus; + unsigned long interval_msec = params[0]; + unsigned long duration = params[1] * HZ / 1000; + unsigned long timeout = jiffies + params[2] * HZ / 1000; + unsigned long last_jiffies; + u32 last, cur; + int rc; + + if ((rc = sata_scr_read(ap, SCR_STATUS, &cur))) + return rc; + cur &= 0xf; + + last = cur; + last_jiffies = jiffies; + + while (1) { + msleep(interval_msec); + if ((rc = sata_scr_read(ap, SCR_STATUS, &cur))) + return rc; + cur &= 0xf; + + /* DET stable? */ + if (cur == last) { + if (cur == 1 && time_before(jiffies, timeout)) + continue; + if (time_after(jiffies, last_jiffies + duration)) + return 0; + continue; + } + + /* unstable, start over */ + last = cur; + last_jiffies = jiffies; + + /* check timeout */ + if (time_after(jiffies, timeout)) + return -EBUSY; + } +} + +/** + * sata_phy_resume - resume SATA phy + * @ap: ATA port to resume SATA phy for + * @params: timing parameters { interval, duratinon, timeout } in msec + * + * Resume SATA phy of @ap and debounce it. + * + * LOCKING: + * Kernel thread context (may sleep) + * + * RETURNS: + * 0 on success, -errno on failure. + */ +int sata_phy_resume(struct ata_port *ap, const unsigned long *params) +{ + u32 scontrol; int rc; if ((rc = sata_scr_read(ap, SCR_CONTROL, &scontrol))) @@ -2441,16 +2517,12 @@ static int sata_phy_resume(struct ata_port *ap) if ((rc = sata_scr_write(ap, SCR_CONTROL, scontrol))) return rc; - /* Wait for phy to become ready, if necessary. */ - do { - msleep(200); - if ((rc = sata_scr_read(ap, SCR_STATUS, &sstatus))) - return rc; - if ((sstatus & 0xf) != 1) - return 0; - } while (time_before(jiffies, timeout)); + /* Some PHYs react badly if SStatus is pounded immediately + * after resuming. Delay 200ms before debouncing. + */ + msleep(200); - return -EBUSY; + return sata_phy_debounce(ap, params); } /** @@ -2468,8 +2540,10 @@ static int sata_phy_resume(struct ata_port *ap) */ void ata_std_probeinit(struct ata_port *ap) { + static const unsigned long deb_timing[] = { 5, 100, 5000 }; + /* resume link */ - sata_phy_resume(ap); + sata_phy_resume(ap, deb_timing); /* wait for device */ if (ata_port_online(ap)) @@ -2585,7 +2659,7 @@ int sata_std_hardreset(struct ata_port *ap, unsigned int *class) msleep(1); /* bring phy back */ - sata_phy_resume(ap); + sata_phy_resume(ap, sata_deb_timing_eh); /* TODO: phy layer with polling, timeouts, etc. */ if (ata_port_offline(ap)) { @@ -5718,6 +5792,9 @@ u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val, * Do not depend on ABI/API stability. */ +EXPORT_SYMBOL_GPL(sata_deb_timing_boot); +EXPORT_SYMBOL_GPL(sata_deb_timing_eh); +EXPORT_SYMBOL_GPL(sata_deb_timing_before_fsrst); EXPORT_SYMBOL_GPL(ata_std_bios_param); EXPORT_SYMBOL_GPL(ata_std_ports); EXPORT_SYMBOL_GPL(ata_device_add); @@ -5757,6 +5834,8 @@ EXPORT_SYMBOL_GPL(ata_bmdma_error_handler); EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd); EXPORT_SYMBOL_GPL(ata_port_probe); EXPORT_SYMBOL_GPL(sata_set_spd); +EXPORT_SYMBOL_GPL(sata_phy_debounce); +EXPORT_SYMBOL_GPL(sata_phy_resume); EXPORT_SYMBOL_GPL(sata_phy_reset); EXPORT_SYMBOL_GPL(__sata_phy_reset); EXPORT_SYMBOL_GPL(ata_bus_reset); diff --git a/include/linux/libata.h b/include/linux/libata.h index c0513c752751..1c167f728fb4 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -607,11 +607,17 @@ struct ata_timing { #define FIT(v,vmin,vmax) max_t(short,min_t(short,v,vmax),vmin) +extern const unsigned long sata_deb_timing_boot[]; +extern const unsigned long sata_deb_timing_eh[]; +extern const unsigned long sata_deb_timing_before_fsrst[]; + extern void ata_port_probe(struct ata_port *); extern void __sata_phy_reset(struct ata_port *ap); extern void sata_phy_reset(struct ata_port *ap); extern void ata_bus_reset(struct ata_port *ap); extern int sata_set_spd(struct ata_port *ap); +extern int sata_phy_debounce(struct ata_port *ap, const unsigned long *param); +extern int sata_phy_resume(struct ata_port *ap, const unsigned long *param); extern int ata_drive_probe_reset(struct ata_port *ap, ata_probeinit_fn_t probeinit, ata_reset_fn_t softreset, ata_reset_fn_t hardreset,