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spi: bcm2835: Use phys addresses for slave DMA config
Contrary to what struct snd_dmaengine_dai_dma_data suggests, the configuration of addresses of DMA slave interfaces should be done in CPU physical addresses. Signed-off-by: Phil Elwell <[email protected]>
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drivers/spi/spi-bcm2835.c

Lines changed: 7 additions & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -119,6 +119,7 @@ MODULE_PARM_DESC(polling_limit_us,
119119
*/
120120
struct bcm2835_spi {
121121
void __iomem *regs;
122+
phys_addr_t phys_addr;
122123
struct clk *clk;
123124
struct gpio_desc *cs_gpio;
124125
unsigned long clk_hz;
@@ -891,19 +892,8 @@ static int bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev,
891892
struct bcm2835_spi *bs)
892893
{
893894
struct dma_slave_config slave_config;
894-
const __be32 *addr;
895-
dma_addr_t dma_reg_base;
896895
int ret;
897896

898-
/* base address in dma-space */
899-
addr = of_get_address(ctlr->dev.of_node, 0, NULL, NULL);
900-
if (!addr) {
901-
dev_err(dev, "could not get DMA-register address - not using dma mode\n");
902-
/* Fall back to interrupt mode */
903-
return 0;
904-
}
905-
dma_reg_base = be32_to_cpup(addr);
906-
907897
/* get tx/rx dma */
908898
ctlr->dma_tx = dma_request_chan(dev, "tx");
909899
if (IS_ERR(ctlr->dma_tx)) {
@@ -925,7 +915,7 @@ static int bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev,
925915
* or, in case of an RX-only transfer, cyclically copies from the zero
926916
* page to the FIFO using a preallocated, reusable descriptor.
927917
*/
928-
slave_config.dst_addr = (u32)(dma_reg_base + BCM2835_SPI_FIFO);
918+
slave_config.dst_addr = bs->phys_addr + BCM2835_SPI_FIFO;
929919
slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
930920

931921
ret = dmaengine_slave_config(ctlr->dma_tx, &slave_config);
@@ -964,9 +954,9 @@ static int bcm2835_dma_init(struct spi_controller *ctlr, struct device *dev,
964954
* RX FIFO or, in case of a TX-only transfer, cyclically writes a
965955
* precalculated value to the CS register to clear the RX FIFO.
966956
*/
967-
slave_config.src_addr = (u32)(dma_reg_base + BCM2835_SPI_FIFO);
957+
slave_config.src_addr = bs->phys_addr + BCM2835_SPI_FIFO;
968958
slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
969-
slave_config.dst_addr = (u32)(dma_reg_base + BCM2835_SPI_CS);
959+
slave_config.dst_addr = bs->phys_addr + BCM2835_SPI_CS;
970960
slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
971961

972962
ret = dmaengine_slave_config(ctlr->dma_rx, &slave_config);
@@ -1346,6 +1336,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
13461336
{
13471337
struct spi_controller *ctlr;
13481338
struct bcm2835_spi *bs;
1339+
struct resource *iomem;
13491340
int err;
13501341

13511342
ctlr = devm_spi_alloc_host(&pdev->dev, sizeof(*bs));
@@ -1369,10 +1360,11 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
13691360
bs = spi_controller_get_devdata(ctlr);
13701361
bs->ctlr = ctlr;
13711362

1372-
bs->regs = devm_platform_ioremap_resource(pdev, 0);
1363+
bs->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &iomem);
13731364
if (IS_ERR(bs->regs))
13741365
return PTR_ERR(bs->regs);
13751366

1367+
bs->phys_addr = iomem->start;
13761368
bs->clk = devm_clk_get_enabled(&pdev->dev, NULL);
13771369
if (IS_ERR(bs->clk))
13781370
return dev_err_probe(&pdev->dev, PTR_ERR(bs->clk),

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