2 files changed, 60 insertions, 6 deletions

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ff59d2e0475b..785bbdcf4a58 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -7,6 +7,10 @@
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or (at
  * your option) any later version.
+ *
+ * Thanks to the following companies for their support:
+ *
+ *     - JMicron (hardware and technical support)
  */
 
 #include <linux/delay.h>
@@ -26,13 +30,29 @@
 
 static unsigned int debug_quirks = 0;
 
+/*
+ * Different quirks to handle when the hardware deviates from a strict
+ * interpretation of the SDHCI specification.
+ */
+
+/* Controller doesn't honor resets unless we touch the clock register */
 #define SDHCI_QUIRK_CLOCK_BEFORE_RESET                  (1<<0)
+/* Controller has bad caps bits, but really supports DMA */
 #define SDHCI_QUIRK_FORCE_DMA                           (1<<1)
 /* Controller doesn't like some resets when there is no card inserted. */
 #define SDHCI_QUIRK_NO_CARD_NO_RESET                    (1<<2)
+/* Controller doesn't like clearing the power reg before a change */
 #define SDHCI_QUIRK_SINGLE_POWER_WRITE                  (1<<3)
+/* Controller has flaky internal state so reset it on each ios change */
 #define SDHCI_QUIRK_RESET_CMD_DATA_ON_IOS               (1<<4)
+/* Controller has an unusable DMA engine */
 #define SDHCI_QUIRK_BROKEN_DMA                          (1<<5)
+/* Controller can only DMA from 32-bit aligned addresses */
+#define SDHCI_QUIRK_32BIT_DMA_ADDR                      (1<<6)
+/* Controller can only DMA chunk sizes that are a multiple of 32 bits */
+#define SDHCI_QUIRK_32BIT_DMA_SIZE                      (1<<7)
+/* Controller needs to be reset after each request to stay stable */
+#define SDHCI_QUIRK_RESET_AFTER_REQUEST                 (1<<8)
 
 static const struct pci_device_id pci_ids[] __devinitdata = {
         {
@@ -97,6 +117,16 @@ static const struct pci_device_id pci_ids[] __devinitdata = {
                                   SDHCI_QUIRK_RESET_CMD_DATA_ON_IOS,
         },
 
+        {
+                .vendor         = PCI_VENDOR_ID_JMICRON,
+                .device         = PCI_DEVICE_ID_JMICRON_JMB38X_SD,
+                .subvendor      = PCI_ANY_ID,
+                .subdevice      = PCI_ANY_ID,
+                .driver_data    = SDHCI_QUIRK_32BIT_DMA_ADDR |
+                                  SDHCI_QUIRK_32BIT_DMA_SIZE |
+                                  SDHCI_QUIRK_RESET_AFTER_REQUEST,
+        },
+
         {       /* Generic SD host controller */
                 PCI_DEVICE_CLASS((PCI_CLASS_SYSTEM_SDHCI << 8), 0xFFFF00)
         },
@@ -419,7 +449,29 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_data *data)
 
         writeb(count, host->ioaddr + SDHCI_TIMEOUT_CONTROL);
 
-        if (host->flags & SDHCI_USE_DMA) {
+        if (host->flags & SDHCI_USE_DMA)
+                host->flags |= SDHCI_REQ_USE_DMA;
+
+        if (unlikely((host->flags & SDHCI_REQ_USE_DMA) &&
+                (host->chip->quirks & SDHCI_QUIRK_32BIT_DMA_SIZE) &&
+                ((data->blksz * data->blocks) & 0x3))) {
+                DBG("Reverting to PIO because of transfer size (%d)\n",
+                        data->blksz * data->blocks);
+                host->flags &= ~SDHCI_REQ_USE_DMA;
+        }
+
+        /*
+         * The assumption here being that alignment is the same after
+         * translation to device address space.
+         */
+        if (unlikely((host->flags & SDHCI_REQ_USE_DMA) &&
+                (host->chip->quirks & SDHCI_QUIRK_32BIT_DMA_ADDR) &&
+                (data->sg->offset & 0x3))) {
+                DBG("Reverting to PIO because of bad alignment\n");
+                host->flags &= ~SDHCI_REQ_USE_DMA;
+        }
+
+        if (host->flags & SDHCI_REQ_USE_DMA) {
                 int count;
 
                 count = pci_map_sg(host->chip->pdev, data->sg, data->sg_len,
@@ -456,7 +508,7 @@ static void sdhci_set_transfer_mode(struct sdhci_host *host,
                 mode |= SDHCI_TRNS_MULTI;
         if (data->flags & MMC_DATA_READ)
                 mode |= SDHCI_TRNS_READ;
-        if (host->flags & SDHCI_USE_DMA)
+        if (host->flags & SDHCI_REQ_USE_DMA)
                 mode |= SDHCI_TRNS_DMA;
 
         writew(mode, host->ioaddr + SDHCI_TRANSFER_MODE);
@@ -472,7 +524,7 @@ static void sdhci_finish_data(struct sdhci_host *host)
         data = host->data;
         host->data = NULL;
 
-        if (host->flags & SDHCI_USE_DMA) {
+        if (host->flags & SDHCI_REQ_USE_DMA) {
                 pci_unmap_sg(host->chip->pdev, data->sg, data->sg_len,
                         (data->flags & MMC_DATA_READ)?PCI_DMA_FROMDEVICE:PCI_DMA_TODEVICE);
         }
@@ -886,7 +938,8 @@ static void sdhci_tasklet_finish(unsigned long param)
          */
         if (mrq->cmd->error ||
                 (mrq->data && (mrq->data->error ||
-                (mrq->data->stop && mrq->data->stop->error)))) {
+                (mrq->data->stop && mrq->data->stop->error))) ||
+                (host->chip->quirks & SDHCI_QUIRK_RESET_AFTER_REQUEST)) {
 
                 /* Some controllers need this kick or reset won't work here */
                 if (host->chip->quirks & SDHCI_QUIRK_CLOCK_BEFORE_RESET) {
@@ -1284,7 +1337,7 @@ static int __devinit sdhci_probe_slot(struct pci_dev *pdev, int slot)
 
         version = readw(host->ioaddr + SDHCI_HOST_VERSION);
         version = (version & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT;
-        if (version != 0) {
+        if (version > 1) {
                 printk(KERN_ERR "%s: Unknown controller version (%d). "
                         "You may experience problems.\n", host->slot_descr,
                         version);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 05195ea900f4..e4d77b038bfa 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -171,7 +171,8 @@ struct sdhci_host {
         spinlock_t              lock;           /* Mutex */
 
         int                     flags;          /* Host attributes */
-#define SDHCI_USE_DMA           (1<<0)
+#define SDHCI_USE_DMA           (1<<0)          /* Host is DMA capable */
+#define SDHCI_REQ_USE_DMA       (1<<1)          /* Use DMA for this req. */
 
         unsigned int            max_clk;        /* Max possible freq (MHz) */
         unsigned int            timeout_clk;    /* Timeout freq (KHz) */