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path: root/drivers/spi/spi-atmel.c
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Diffstat (limited to 'drivers/spi/spi-atmel.c')
-rw-r--r--drivers/spi/spi-atmel.c115
1 files changed, 85 insertions, 30 deletions
diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index f95da364c283..4a11fc0d4136 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -291,6 +291,10 @@ struct atmel_spi {
struct spi_transfer *current_transfer;
int current_remaining_bytes;
int done_status;
+ dma_addr_t dma_addr_rx_bbuf;
+ dma_addr_t dma_addr_tx_bbuf;
+ void *addr_rx_bbuf;
+ void *addr_tx_bbuf;
struct completion xfer_completion;
@@ -436,6 +440,11 @@ static void atmel_spi_unlock(struct atmel_spi *as) __releases(&as->lock)
spin_unlock_irqrestore(&as->lock, as->flags);
}
+static inline bool atmel_spi_is_vmalloc_xfer(struct spi_transfer *xfer)
+{
+ return is_vmalloc_addr(xfer->tx_buf) || is_vmalloc_addr(xfer->rx_buf);
+}
+
static inline bool atmel_spi_use_dma(struct atmel_spi *as,
struct spi_transfer *xfer)
{
@@ -448,7 +457,12 @@ static bool atmel_spi_can_dma(struct spi_master *master,
{
struct atmel_spi *as = spi_master_get_devdata(master);
- return atmel_spi_use_dma(as, xfer);
+ if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5))
+ return atmel_spi_use_dma(as, xfer) &&
+ !atmel_spi_is_vmalloc_xfer(xfer);
+ else
+ return atmel_spi_use_dma(as, xfer);
+
}
static int atmel_spi_dma_slave_config(struct atmel_spi *as,
@@ -594,6 +608,11 @@ static void dma_callback(void *data)
struct spi_master *master = data;
struct atmel_spi *as = spi_master_get_devdata(master);
+ if (is_vmalloc_addr(as->current_transfer->rx_buf) &&
+ IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) {
+ memcpy(as->current_transfer->rx_buf, as->addr_rx_bbuf,
+ as->current_transfer->len);
+ }
complete(&as->xfer_completion);
}
@@ -744,17 +763,41 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
goto err_exit;
/* Send both scatterlists */
- rxdesc = dmaengine_prep_slave_sg(rxchan,
- xfer->rx_sg.sgl, xfer->rx_sg.nents,
- DMA_FROM_DEVICE,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (atmel_spi_is_vmalloc_xfer(xfer) &&
+ IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) {
+ rxdesc = dmaengine_prep_slave_single(rxchan,
+ as->dma_addr_rx_bbuf,
+ xfer->len,
+ DMA_FROM_DEVICE,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ rxdesc = dmaengine_prep_slave_sg(rxchan,
+ xfer->rx_sg.sgl,
+ xfer->rx_sg.nents,
+ DMA_FROM_DEVICE,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ }
if (!rxdesc)
goto err_dma;
- txdesc = dmaengine_prep_slave_sg(txchan,
- xfer->tx_sg.sgl, xfer->tx_sg.nents,
- DMA_TO_DEVICE,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (atmel_spi_is_vmalloc_xfer(xfer) &&
+ IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) {
+ memcpy(as->addr_tx_bbuf, xfer->tx_buf, xfer->len);
+ txdesc = dmaengine_prep_slave_single(txchan,
+ as->dma_addr_tx_bbuf,
+ xfer->len, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ } else {
+ txdesc = dmaengine_prep_slave_sg(txchan,
+ xfer->tx_sg.sgl,
+ xfer->tx_sg.nents,
+ DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT |
+ DMA_CTRL_ACK);
+ }
if (!txdesc)
goto err_dma;
@@ -1426,27 +1469,7 @@ static void atmel_get_caps(struct atmel_spi *as)
as->caps.is_spi2 = version > 0x121;
as->caps.has_wdrbt = version >= 0x210;
-#ifdef CONFIG_SOC_SAM_V4_V5
- /*
- * Atmel SoCs based on ARM9 (SAM9x) cores should not use spi_map_buf()
- * since this later function tries to map buffers with dma_map_sg()
- * even if they have not been allocated inside DMA-safe areas.
- * On SoCs based on Cortex A5 (SAMA5Dx), it works anyway because for
- * those ARM cores, the data cache follows the PIPT model.
- * Also the L2 cache controller of SAMA5D2 uses the PIPT model too.
- * In case of PIPT caches, there cannot be cache aliases.
- * However on ARM9 cores, the data cache follows the VIVT model, hence
- * the cache aliases issue can occur when buffers are allocated from
- * DMA-unsafe areas, by vmalloc() for instance, where cache coherency is
- * not taken into account or at least not handled completely (cache
- * lines of aliases are not invalidated).
- * This is not a theorical issue: it was reproduced when trying to mount
- * a UBI file-system on a at91sam9g35ek board.
- */
- as->caps.has_dma_support = false;
-#else
as->caps.has_dma_support = version >= 0x212;
-#endif
as->caps.has_pdc_support = version < 0x212;
}
@@ -1592,6 +1615,30 @@ static int atmel_spi_probe(struct platform_device *pdev)
as->use_pdc = true;
}
+ if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) {
+ as->addr_rx_bbuf = dma_alloc_coherent(&pdev->dev,
+ SPI_MAX_DMA_XFER,
+ &as->dma_addr_rx_bbuf,
+ GFP_KERNEL | GFP_DMA);
+ if (!as->addr_rx_bbuf) {
+ as->use_dma = false;
+ } else {
+ as->addr_tx_bbuf = dma_alloc_coherent(&pdev->dev,
+ SPI_MAX_DMA_XFER,
+ &as->dma_addr_tx_bbuf,
+ GFP_KERNEL | GFP_DMA);
+ if (!as->addr_tx_bbuf) {
+ as->use_dma = false;
+ dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER,
+ as->addr_rx_bbuf,
+ as->dma_addr_rx_bbuf);
+ }
+ }
+ if (!as->use_dma)
+ dev_info(master->dev.parent,
+ " can not allocate dma coherent memory\n");
+ }
+
if (as->caps.has_dma_support && !as->use_dma)
dev_info(&pdev->dev, "Atmel SPI Controller using PIO only\n");
@@ -1661,12 +1708,20 @@ static int atmel_spi_remove(struct platform_device *pdev)
pm_runtime_get_sync(&pdev->dev);
/* reset the hardware and block queue progress */
- spin_lock_irq(&as->lock);
if (as->use_dma) {
atmel_spi_stop_dma(master);
atmel_spi_release_dma(master);
+ if (IS_ENABLED(CONFIG_SOC_SAM_V4_V5)) {
+ dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER,
+ as->addr_tx_bbuf,
+ as->dma_addr_tx_bbuf);
+ dma_free_coherent(&pdev->dev, SPI_MAX_DMA_XFER,
+ as->addr_rx_bbuf,
+ as->dma_addr_rx_bbuf);
+ }
}
+ spin_lock_irq(&as->lock);
spi_writel(as, CR, SPI_BIT(SWRST));
spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
spi_readl(as, SR);

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