I have found that the IDE controller on a w83c553f (a sl82c105 function)
can get into a hung state if the interrupt line is wired to INTC and a
timeout occurs. The following patch implements a hard reset for the
controller as documented in a Windbond engineering notice.
This patch needs some testing and there appears to be no maintainer for
the sl83c105 IDE driver :(. The conditions to repeat the problem are
that the controller must be wired for PCI INTC, DMA must be in use, and
a timeout error must occur (try mounting a music CD). My fix checks for
INTC configuration so hopefully this patch will only affect systems that
exhibit the hang. I have tested it on an IBM pSeries model 610 which
has the hardware operating in this mode.
The patch should apply to 2.5.13 - 2.5.16 (at least).
-todd
--- drivers/ide/sl82c105.c 16 Aug 2001 13:50:23 -0000 1.3
+++ drivers/ide/sl82c105.c 17 Dec 2001 19:14:28 -0000
@@ -156,6 +156,29 @@
}
/*
+ * Reset the controller.
+ * If we are using INTC under a w83c553 we need to use a magic test
+ * bit to do this. Return zero if successful (or applicable).
+ *
+ */
+static int sl82c105_hard_reset(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = HWIF(drive);
+ struct pci_dev *dev = hwif->pci_dev;
+ unsigned int reg;
+
+ pci_read_config_dword(dev, 0x40, ®); /* LEGIRQ register */
+ if (reg & (1<<11)) { /* Using INTC? */
+ printk("sl82c105: resetting device\n");
+ pci_read_config_dword(dev, 0x7e, ®);
+ pci_write_config_word(dev, 0x7e, reg | (1<<2));
+ pci_write_config_word(dev, 0x7e, reg & (~(1<<2)));
+ return 0;
+ }
+ return 1;
+}
+
+/*
* Our own dmaproc, only to intercept ide_dma_check
*/
static int sl82c105_dmaproc(ide_dma_action_t func, ide_drive_t *drive)
@@ -171,6 +194,11 @@
case ide_dma_off:
config_for_pio(drive, 4, 0);
break;
+ case ide_dma_lostirq:
+ case ide_dma_timeout:
+ if (sl82c105_hard_reset(drive) == 0)
+ return 0;
+ break;
default:
break;
}
-
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This archive was generated by hypermail 2b29 : Sun Dec 23 2001 - 21:00:15 EST