[PATCH] sata_sil24: implement loss of completion interrupt on PCI-X errta fix
SiI3124 might lose completion interrupt if completion interrupt occurs
shortly after SLOT_STAT register is read for the previous completion
interrupt if it is operating in PCI-X mode.
This currently doesn't trigger as libata never queues more than one
command, but it will with NCQ changes. This patch implements the
workaround - turning on WoC and explicitly clearing interrupt.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index 50c2c6b..c535607 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -221,6 +221,7 @@
/* host flags */
SIL24_COMMON_FLAGS = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA,
+ SIL24_FLAG_PCIX_IRQ_WOC = (1 << 24), /* IRQ loss errata on PCI-X */
IRQ_STAT_4PORTS = 0xf,
};
@@ -348,7 +349,8 @@
/* sil_3124 */
{
.sht = &sil24_sht,
- .host_flags = SIL24_COMMON_FLAGS | SIL24_NPORTS2FLAG(4),
+ .host_flags = SIL24_COMMON_FLAGS | SIL24_NPORTS2FLAG(4) |
+ SIL24_FLAG_PCIX_IRQ_WOC,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x3f, /* udma0-5 */
@@ -737,6 +739,10 @@
slot_stat = readl(port + PORT_SLOT_STAT);
if (!(slot_stat & HOST_SSTAT_ATTN)) {
struct sil24_port_priv *pp = ap->private_data;
+
+ if (ap->flags & SIL24_FLAG_PCIX_IRQ_WOC)
+ writel(PORT_IRQ_COMPLETE, port + PORT_IRQ_STAT);
+
/*
* !HOST_SSAT_ATTN guarantees successful completion,
* so reading back tf registers is unnecessary for
@@ -868,6 +874,7 @@
void __iomem *host_base = NULL;
void __iomem *port_base = NULL;
int i, rc;
+ u32 tmp;
if (!printed_version++)
dev_printk(KERN_DEBUG, &pdev->dev, "version " DRV_VERSION "\n");
@@ -941,13 +948,23 @@
/* GPIO off */
writel(0, host_base + HOST_FLASH_CMD);
+ /* Apply workaround for completion IRQ loss on PCI-X errata */
+ if (probe_ent->host_flags & SIL24_FLAG_PCIX_IRQ_WOC) {
+ tmp = readl(host_base + HOST_CTRL);
+ if (tmp & (HOST_CTRL_TRDY | HOST_CTRL_STOP | HOST_CTRL_DEVSEL))
+ dev_printk(KERN_INFO, &pdev->dev,
+ "Applying completion IRQ loss on PCI-X "
+ "errata fix\n");
+ else
+ probe_ent->host_flags &= ~SIL24_FLAG_PCIX_IRQ_WOC;
+ }
+
/* clear global reset & mask interrupts during initialization */
writel(0, host_base + HOST_CTRL);
for (i = 0; i < probe_ent->n_ports; i++) {
void __iomem *port = port_base + i * PORT_REGS_SIZE;
unsigned long portu = (unsigned long)port;
- u32 tmp;
probe_ent->port[i].cmd_addr = portu + PORT_PRB;
probe_ent->port[i].scr_addr = portu + PORT_SCONTROL;
@@ -969,6 +986,12 @@
"failed to clear port RST\n");
}
+ /* Configure IRQ WoC */
+ if (probe_ent->host_flags & SIL24_FLAG_PCIX_IRQ_WOC)
+ writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_STAT);
+ else
+ writel(PORT_CS_IRQ_WOC, port + PORT_CTRL_CLR);
+
/* Zero error counters. */
writel(0x8000, port + PORT_DECODE_ERR_THRESH);
writel(0x8000, port + PORT_CRC_ERR_THRESH);
