From 7b91369b46559dcc90e8d414e31c0257972e0cbb Mon Sep 17 00:00:00 2001 From: Alexandre Courbot Date: Mon, 7 Mar 2016 11:07:55 +0900 Subject: [PATCH] mmc: sdhci: Set DMA mask when adding host 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 Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci.c | 48 ++++++++++++++++++++++++++++++++++------ 1 file changed, 41 insertions(+), 7 deletions(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 4ae394e9e560..8670f162dec7 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2804,6 +2804,36 @@ 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)); + host->flags &= ~SDHCI_USE_64_BIT_DMA; + } + } + + /* 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; @@ -2879,13 +2909,17 @@ 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; } } -- 2.20.1