[MMC] sdhci: more DMA capabilities tests
Properly test for controller interface to see if it's DMA capable. As many
controllers are misconfigured in this regard, also add debug parameters to
force DMA support either way.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 06dec74..315ab49 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -28,6 +28,9 @@
#define DBG(f, x...) \
pr_debug(DRIVER_NAME " [%s()]: " f, __func__,## x)
+static unsigned int debug_nodma = 0;
+static unsigned int debug_forcedma = 0;
+
static const struct pci_device_id pci_ids[] __devinitdata = {
/* handle any SD host controller */
{PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)},
@@ -1105,6 +1108,16 @@
return -ENODEV;
}
+ if ((pdev->class & 0x0000FF) == PCI_SDHCI_IFVENDOR) {
+ printk(KERN_ERR DRIVER_NAME ": Vendor specific interface. Aborting.\n");
+ return -ENODEV;
+ }
+
+ if ((pdev->class & 0x0000FF) > PCI_SDHCI_IFVENDOR) {
+ printk(KERN_ERR DRIVER_NAME ": Unknown interface. Aborting.\n");
+ return -ENODEV;
+ }
+
mmc = mmc_alloc_host(sizeof(struct sdhci_host), &pdev->dev);
if (!mmc)
return -ENOMEM;
@@ -1146,7 +1159,16 @@
caps = readl(host->ioaddr + SDHCI_CAPABILITIES);
- if ((caps & SDHCI_CAN_DO_DMA) && ((pdev->class & 0x0000FF) == 0x01))
+ if (debug_nodma)
+ DBG("DMA forced off\n");
+ else if (debug_forcedma) {
+ DBG("DMA forced on\n");
+ host->flags |= SDHCI_USE_DMA;
+ } else if ((pdev->class & 0x0000FF) != PCI_SDHCI_IFDMA)
+ DBG("Controller doesn't have DMA interface\n");
+ else if (!(caps & SDHCI_CAN_DO_DMA))
+ DBG("Controller doesn't have DMA capability\n");
+ else
host->flags |= SDHCI_USE_DMA;
if (host->flags & SDHCI_USE_DMA) {
@@ -1429,7 +1451,13 @@
module_init(sdhci_drv_init);
module_exit(sdhci_drv_exit);
+module_param(debug_nodma, uint, 0444);
+module_param(debug_forcedma, uint, 0444);
+
MODULE_AUTHOR("Pierre Ossman <drzeus@drzeus.cx>");
MODULE_DESCRIPTION("Secure Digital Host Controller Interface driver");
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");
+
+MODULE_PARM_DESC(debug_nodma, "Forcefully disable DMA transfers. (default 0)");
+MODULE_PARM_DESC(debug_forcedma, "Forcefully enable DMA transfers. (default 0)");
diff --git a/drivers/mmc/sdhci.h b/drivers/mmc/sdhci.h
index 758cf1c..8111fa3 100644
--- a/drivers/mmc/sdhci.h
+++ b/drivers/mmc/sdhci.h
@@ -12,6 +12,10 @@
* PCI registers
*/
+#define PCI_SDHCI_IFPIO 0x00
+#define PCI_SDHCI_IFDMA 0x01
+#define PCI_SDHCI_IFVENDOR 0x02
+
#define PCI_SLOT_INFO 0x40 /* 8 bits */
#define PCI_SLOT_INFO_SLOTS(x) ((x >> 4) & 7)
#define PCI_SLOT_INFO_FIRST_BAR_MASK 0x07