From d4b2bab4f26345ea1803feb23ea92fbe3f6b77bc Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 2 Feb 2007 16:50:52 +0900 Subject: libata: add deadline support to prereset and reset methods Add @deadline to prereset and reset methods and make them honor it. ata_wait_ready() which directly takes @deadline is implemented to be used as the wait function. This patch is in preparation for EH timing improvements. * ata_wait_ready() never does busy sleep. It's only used from EH and no wait in EH is that urgent. This function also prints 'be patient' message automatically after 5 secs of waiting if more than 3 secs is remaining till deadline. * ata_bus_post_reset() now fails with error code if any of its wait fails. This is important because earlier reset tries will have shorter timeout than the spec requires. If a device fails to respond before the short timeout, reset should be retried with longer timeout rather than silently ignoring the device. There are three behavior differences. 1. Timeout is applied to both devices at once, not separately. This is more consistent with what the spec says. 2. When a device passes devchk but fails to become ready before deadline. Previouly, post_reset would just succeed and let device classification remove the device. New code fails the reset thus causing reset retry. After a few times, EH will give up disabling the port. 3. When slave device passes devchk but fails to become accessible (TF-wise) after reset. Original code disables dev1 after 30s timeout and continues as if the device doesn't exist, while the patched code fails reset. When this happens, new code fails reset on whole port rather than proceeding with only the primary device. If the failing device is suffering transient problems, new code retries reset which is a better behavior. If the failing device is actually broken, the net effect is identical to it, but not to the other device sharing the channel. In the previous code, reset would have succeeded after 30s thus detecting the working one. In the new code, reset fails and whole port gets disabled. IMO, it's a pathological case anyway (broken device sharing bus with working one) and doesn't really matter. * ata_bus_softreset() is changed to return error code from ata_bus_post_reset(). It used to return 0 unconditionally. * Spin up waiting is to be removed and not converted to honor deadline. * To be on the safe side, deadline is set to 40s for the time being. Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/ata/pata_hpt3x2n.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/ata/pata_hpt3x2n.c') diff --git a/drivers/ata/pata_hpt3x2n.c b/drivers/ata/pata_hpt3x2n.c index 6a34521b9e0..ea1037d6786 100644 --- a/drivers/ata/pata_hpt3x2n.c +++ b/drivers/ata/pata_hpt3x2n.c @@ -148,13 +148,14 @@ static int hpt3x2n_cable_detect(struct ata_port *ap) * Reset the hardware and state machine, */ -static int hpt3xn_pre_reset(struct ata_port *ap) +static int hpt3xn_pre_reset(struct ata_port *ap, unsigned long deadline) { struct pci_dev *pdev = to_pci_dev(ap->host->dev); /* Reset the state machine */ pci_write_config_byte(pdev, 0x50 + 4 * ap->port_no, 0x37); udelay(100); - return ata_std_prereset(ap); + + return ata_std_prereset(ap, deadline); } /** -- cgit v1.2.3-18-g5258