diff options
Diffstat (limited to 'drivers/ata/libata-core.c')
| -rw-r--r-- | drivers/ata/libata-core.c | 38 |
1 files changed, 31 insertions, 7 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 22ff51bdbc8a..6728328f3bea 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -3790,21 +3790,45 @@ int sata_link_debounce(struct ata_link *link, const unsigned long *params, int sata_link_resume(struct ata_link *link, const unsigned long *params, unsigned long deadline) { + int tries = ATA_LINK_RESUME_TRIES; u32 scontrol, serror; int rc; if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol))) return rc; - scontrol = (scontrol & 0x0f0) | 0x300; + /* + * Writes to SControl sometimes get ignored under certain + * controllers (ata_piix SIDPR). Make sure DET actually is + * cleared. + */ + do { + scontrol = (scontrol & 0x0f0) | 0x300; + if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol))) + return rc; + /* + * Some PHYs react badly if SStatus is pounded + * immediately after resuming. Delay 200ms before + * debouncing. + */ + msleep(200); - if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol))) - return rc; + /* is SControl restored correctly? */ + if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol))) + return rc; + } while ((scontrol & 0xf0f) != 0x300 && --tries); - /* Some PHYs react badly if SStatus is pounded immediately - * after resuming. Delay 200ms before debouncing. - */ - msleep(200); + if ((scontrol & 0xf0f) != 0x300) { + ata_link_printk(link, KERN_ERR, + "failed to resume link (SControl %X)\n", + scontrol); + return 0; + } + + if (tries < ATA_LINK_RESUME_TRIES) + ata_link_printk(link, KERN_WARNING, + "link resume succeeded after %d retries\n", + ATA_LINK_RESUME_TRIES - tries); if ((rc = sata_link_debounce(link, params, deadline))) return rc; |