mmc: sdhci: Fix ADMA for PAGE_SIZE >= 64KiB

[sfrench/cifs-2.6.git] / drivers / mmc / host / sdhci.c

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 269c865694024c8f2164574349352a299eacf5d2..07c6da1f2f0fe7b38414ab0afa273c3f912ec20e 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -771,7 +771,19 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
                        len -= offset;
                }
 
-               BUG_ON(len > 65536);
+               /*
+                * The block layer forces a minimum segment size of PAGE_SIZE,
+                * so 'len' can be too big here if PAGE_SIZE >= 64KiB. Write
+                * multiple descriptors, noting that the ADMA table is sized
+                * for 4KiB chunks anyway, so it will be big enough.
+                */
+               while (len > host->max_adma) {
+                       int n = 32 * 1024; /* 32KiB*/
+
+                       __sdhci_adma_write_desc(host, &desc, addr, n, ADMA2_TRAN_VALID);
+                       addr += n;
+                       len -= n;
+               }
 
                /* tran, valid */
                if (len)
@@ -3968,6 +3980,7 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
         * descriptor for each segment, plus 1 for a nop end descriptor.
         */
        host->adma_table_cnt = SDHCI_MAX_SEGS * 2 + 1;
+       host->max_adma = 65536;
 
        host->max_timeout_count = 0xE;
 
@@ -4633,10 +4646,12 @@ int sdhci_setup_host(struct sdhci_host *host)
         * be larger than 64 KiB though.
         */
        if (host->flags & SDHCI_USE_ADMA) {
-               if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC)
+               if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) {
+                       host->max_adma = 65532; /* 32-bit alignment */
                        mmc->max_seg_size = 65535;
-               else
+               } else {
                        mmc->max_seg_size = 65536;
+               }
        } else {
                mmc->max_seg_size = mmc->max_req_size;
        }