From 664faf09a05d74085c0b31e2c621d7647322325b Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 31 May 2006 18:27:50 +0900 Subject: [PATCH] [PATCH] libata-hp-prep: implement followup softreset handling In some cases, hardreset must be followed by SRST. * some controllers can't classify with hardreset * some controllers can't wait for !BSY after hardreset (LLDD should explicitly request followup softreset by returning -EAGAIN) * (later) PM needs SRST w/ PMP==15 to operate after hardreset To handle above cases, this patch implements follow-up softreset. After a hardreset, ata_eh_reset() checks whether any of above conditions are met and do a follow-up softreset if necessary. Signed-off-by: Tejun Heo --- drivers/scsi/libata-eh.c | 58 +++++++++++++++++++++++++++++++++++----- 1 file changed, 52 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c index 0e66f140e53b..8ecb8424d7ba 100644 --- a/drivers/scsi/libata-eh.c +++ b/drivers/scsi/libata-eh.c @@ -1318,16 +1318,28 @@ static void ata_eh_report(struct ata_port *ap) } } -static int ata_eh_reset(struct ata_port *ap, +static int ata_eh_followup_srst_needed(int rc, int classify, + const unsigned int *classes) +{ + if (rc == -EAGAIN) + return 1; + if (rc != 0) + return 0; + if (classify && classes[0] == ATA_DEV_UNKNOWN) + return 1; + return 0; +} + +static int ata_eh_reset(struct ata_port *ap, int classify, ata_prereset_fn_t prereset, ata_reset_fn_t softreset, ata_reset_fn_t hardreset, ata_postreset_fn_t postreset) { struct ata_eh_context *ehc = &ap->eh_context; - unsigned int classes[ATA_MAX_DEVICES]; + unsigned int *classes = ehc->classes; int tries = ATA_EH_RESET_TRIES; unsigned int action; ata_reset_fn_t reset; - int i, rc; + int i, did_followup_srst, rc; /* Determine which reset to use and record in ehc->i.action. * prereset() may examine and modify it. @@ -1381,10 +1393,44 @@ static int ata_eh_reset(struct ata_port *ap, rc = ata_do_reset(ap, reset, classes); + did_followup_srst = 0; + if (reset == hardreset && + ata_eh_followup_srst_needed(rc, classify, classes)) { + /* okay, let's do follow-up softreset */ + did_followup_srst = 1; + reset = softreset; + + if (!reset) { + ata_port_printk(ap, KERN_ERR, + "follow-up softreset required " + "but no softreset avaliable\n"); + return -EINVAL; + } + + ata_eh_about_to_do(ap, ATA_EH_RESET_MASK); + rc = ata_do_reset(ap, reset, classes); + + if (rc == 0 && classify && + classes[0] == ATA_DEV_UNKNOWN) { + ata_port_printk(ap, KERN_ERR, + "classification failed\n"); + return -EINVAL; + } + } + if (rc && --tries) { + const char *type; + + if (reset == softreset) { + if (did_followup_srst) + type = "follow-up soft"; + else + type = "soft"; + } else + type = "hard"; + ata_port_printk(ap, KERN_WARNING, - "%sreset failed, retrying in 5 secs\n", - reset == softreset ? "soft" : "hard"); + "%sreset failed, retrying in 5 secs\n", type); ssleep(5); if (reset == hardreset) @@ -1508,7 +1554,7 @@ static int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset, if (ehc->i.action & ATA_EH_RESET_MASK) { ata_eh_freeze_port(ap); - rc = ata_eh_reset(ap, prereset, softreset, hardreset, + rc = ata_eh_reset(ap, 0, prereset, softreset, hardreset, postreset); if (rc) { ata_port_printk(ap, KERN_ERR, -- 2.20.1