Set the DMA mask in sdhci_add_host() after we determined the
capabilities of the device. 64-bit devices in particular are given the
proper mask that ensures bounce buffers are not used.
Also disable DMA if no proper DMA mask can be set, as the DMA-API
documentation specifies.
Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 46 +++++++++++++++++++++++++++++++++++++++-------
1 file changed, 39 insertions(+), 7 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index fd9139947fa3..00fb45ba6f39 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2857,6 +2857,34 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
EXPORT_SYMBOL_GPL(sdhci_alloc_host);
+static int sdhci_set_dma_mask(struct sdhci_host *host)
+{
+ struct mmc_host *mmc = host->mmc;
+ struct device *dev = mmc_dev(mmc);
+ int ret = -EINVAL;
+
+ if (host->quirks2 & SDHCI_QUIRK2_BROKEN_64_BIT_DMA)
+ host->flags &= ~SDHCI_USE_64_BIT_DMA;
+
+ /* Try 64-bit mask if hardware is capable of it */
+ if (host->flags & SDHCI_USE_64_BIT_DMA) {
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+ if (ret)
+ pr_warn("%s: Failed to set 64-bit DMA mask.\n",
+ mmc_hostname(mmc));
+ }
+
+ /* 32-bit mask as default & fallback */
+ if (ret) {
+ ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+ if (ret)
+ pr_warn("%s: Failed to set 32-bit DMA mask.\n",
+ mmc_hostname(mmc));
+ }
+
+ return ret;
+}
+
int sdhci_add_host(struct sdhci_host *host)
{
struct mmc_host *mmc;
@@ -2932,13 +2960,17 @@ int sdhci_add_host(struct sdhci_host *host)
host->flags |= SDHCI_USE_64_BIT_DMA;
if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
- if (host->ops->enable_dma) {
- if (host->ops->enable_dma(host)) {
- pr_warn("%s: No suitable DMA available - falling back to PIO\n",
- mmc_hostname(mmc));
- host->flags &=
- ~(SDHCI_USE_SDMA | SDHCI_USE_ADMA);
- }
+ ret = sdhci_set_dma_mask(host);
+
+ if (!ret && host->ops->enable_dma)
+ ret = host->ops->enable_dma(host);
+
+ if (ret) {
+ pr_warn("%s: No suitable DMA available - falling back to PIO\n",
+ mmc_hostname(mmc));
+ host->flags &= ~(SDHCI_USE_SDMA | SDHCI_USE_ADMA);
+
+ ret = 0;
}
}
--
2.7.2
--
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