No luck with the patch. Error occurred right on boot:
ata1.00: exception Emask 0x0 SAct 0x1 SErr 0x0 action 0x6 frozen
ata1.00: cmd 61/08:00:cb:d5:42/00:00:25:00:00/40 tag 0 ncq 4096 out
res 40/00:00:00:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
ata1.00: status: { DRDY }
ata1: hard resetting link
ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata1.00: max_sectors limited to 256 for NCQ
ata1.00: max_sectors limited to 256 for NCQ
ata1.00: configured for UDMA/133
ata1: EH complete
----- Original Message -----
From: "Mark Lord" <liml@xxxxxx>
To: "IDE/ATA development list" <linux-ide@xxxxxxxxxxxxxxx>; "Brian
Rademacher" <rad@xxxxxxxxxxxx>; "Eamonn Hamilton" <EAMONN.HAMILTON@xxxxxxxx>
Sent: Tuesday, January 13, 2009 2:17 PM
Subject: sata_mv: trial fix for lost NCQ interrupts
This patch is for trial/critique use only at the moment.
Once I hear back from a few people who actually use it,
I'll post an updated fix for upstream/backstream inclusion.
I spent this afternoon nitpicking and bitpicking through the interrupt
code
in sata_mv.c, and I believe I found a race on the hc_irq_cause register.
The
code was "helpfully" attempting to use read-modify-write to clear
individual
port bits there, but this is impossible to do in a race-free fashion.
So.. the obvious fix is to just write the bits being cleared, without
touching
anything else. This will also be faster, too, since no read is required
or
desired. I really don't see a downside, as long as it actually works for
everyone.
It does work for me here.
--- linux-2.6.28/drivers/ata/sata_mv.c 2009-01-13 15:57:11.000000000 -0500
+++ linux/drivers/ata/sata_mv.c 2009-01-13 16:03:04.000000000 -0500
@@ -884,18 +884,14 @@
int hardport = mv_hardport_from_port(ap->port_no);
void __iomem *hc_mmio = mv_hc_base_from_port(
mv_host_base(ap->host), hardport);
- u32 hc_irq_cause, ipending;
+ u32 hc_irq_cause;
/* clear EDMA event indicators, if any */
writelfl(0, port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);
- /* clear EDMA interrupt indicator, if any */
- hc_irq_cause = readl(hc_mmio + HC_IRQ_CAUSE_OFS);
- ipending = (DEV_IRQ | DMA_IRQ) << hardport;
- if (hc_irq_cause & ipending) {
- writelfl(hc_irq_cause & ~ipending,
- hc_mmio + HC_IRQ_CAUSE_OFS);
- }
+ /* clear EDMA interrupt indicators */
+ hc_irq_cause = (DEV_IRQ | DMA_IRQ) << hardport;
+ writelfl(~hc_irq_cause, hc_mmio + HC_IRQ_CAUSE_OFS);
mv_edma_cfg(ap, want_ncq);
@@ -2821,10 +2817,9 @@
/* clear EDMA errors on this port */
writel(0, port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);
- /* clear pending irq events */
- hc_irq_cause = readl(hc_mmio + HC_IRQ_CAUSE_OFS);
- hc_irq_cause &= ~((DEV_IRQ | DMA_IRQ) << hardport);
- writelfl(hc_irq_cause, hc_mmio + HC_IRQ_CAUSE_OFS);
+ /* clear EDMA interrupt indicators */
+ hc_irq_cause = (DEV_IRQ | DMA_IRQ) << hardport;
+ writelfl(~hc_irq_cause, hc_mmio + HC_IRQ_CAUSE_OFS);
mv_enable_port_irqs(ap, ERR_IRQ);
}
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