Commit 603ded16 authored by Andres Salomon's avatar Andres Salomon Committed by Linus Torvalds

olpc: sdhci: add quirk for the Marvell CaFe's interrupt timeout

The CaFe chip has a hardware bug that ends up with us getting a timeout
value that's too small, causing the following sorts of problems:

[   60.525138] mmcblk0: error -110 transferring data
[   60.531477] end_request: I/O error, dev mmcblk0, sector 1484353
[   60.533371] Buffer I/O error on device mmcblk0p2, logical block 181632
[   60.533371] lost page write due to I/O error on mmcblk0p2

Presumably this is an off-by-one error in the hardware.  Incrementing
the timeout count value that we stuff into the TIMEOUT_CONTROL register
gets us a value that works.  This bug was originally discovered by
Pierre Ossman, I believe.

[thanks to Robert Millan for proving that this was still a problem]
Signed-off-by: default avatarAndres Salomon <dilinger@debian.org>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent e08c1694
......@@ -57,6 +57,8 @@ static unsigned int debug_quirks = 0;
#define SDHCI_QUIRK_RESET_AFTER_REQUEST (1<<8)
/* Controller needs voltage and power writes to happen separately */
#define SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER (1<<9)
/* Controller has an off-by-one issue with timeout value */
#define SDHCI_QUIRK_INCR_TIMEOUT_CONTROL (1<<10)
static const struct pci_device_id pci_ids[] __devinitdata = {
{
......@@ -134,7 +136,8 @@ static const struct pci_device_id pci_ids[] __devinitdata = {
.device = PCI_DEVICE_ID_MARVELL_CAFE_SD,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
.driver_data = SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER,
.driver_data = SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER |
SDHCI_QUIRK_INCR_TIMEOUT_CONTROL,
},
{
......@@ -479,6 +482,13 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
break;
}
/*
* Compensate for an off-by-one error in the CaFe hardware; otherwise,
* a too-small count gives us interrupt timeouts.
*/
if ((host->chip->quirks & SDHCI_QUIRK_INCR_TIMEOUT_CONTROL))
count++;
if (count >= 0xF) {
printk(KERN_WARNING "%s: Too large timeout requested!\n",
mmc_hostname(host->mmc));
......
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