target/linux/bcm27xx/patches-6.1/950-0719-spi-bcm2835-Use-phys-addresses-for-slave-DMA-config.patch

   1 From b71cfec520b128ce190e70b1c32df8bfc2492d9a Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.com>
   3 Date: Thu, 11 May 2023 16:27:06 +0100
   4 Subject: [PATCH] spi: bcm2835: Use phys addresses for slave DMA config
   5
   6 Contrary to what struct snd_dmaengine_dai_dma_data suggests, the
   7 configuration of addresses of DMA slave interfaces should be done in
   8 CPU physical addresses.
   9
  10 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
  11 ---
  12  drivers/spi/spi-bcm2835.c | 22 +++++++---------------
  13  1 file changed, 7 insertions(+), 15 deletions(-)
  14
  15 --- a/drivers/spi/spi-bcm2835.c
  16 +++ b/drivers/spi/spi-bcm2835.c
  17 @@ -116,6 +116,7 @@ MODULE_PARM_DESC(polling_limit_us,
  18   */
  19  struct bcm2835_spi {
  20         void __iomem *regs;
  21 +       phys_addr_t phys_addr;
  22         struct clk *clk;
  23         unsigned long clk_hz;
  24         int irq;
  25 @@ -887,19 +888,8 @@ static int bcm2835_dma_init(struct spi_c
  26                             struct bcm2835_spi *bs)
  27  {
  28         struct dma_slave_config slave_config;
  29 -       const __be32 *addr;
  30 -       dma_addr_t dma_reg_base;
  31         int ret;
  32
  33 -       /* base address in dma-space */
  34 -       addr = of_get_address(ctlr->dev.of_node, 0, NULL, NULL);
  35 -       if (!addr) {
  36 -               dev_err(dev, "could not get DMA-register address - not using dma mode\n");
  37 -               /* Fall back to interrupt mode */
  38 -               return 0;
  39 -       }
  40 -       dma_reg_base = be32_to_cpup(addr);
  41 -
  42         /* get tx/rx dma */
  43         ctlr->dma_tx = dma_request_chan(dev, "tx");
  44         if (IS_ERR(ctlr->dma_tx)) {
  45 @@ -921,7 +911,7 @@ static int bcm2835_dma_init(struct spi_c
  46          * or, in case of an RX-only transfer, cyclically copies from the zero
  47          * page to the FIFO using a preallocated, reusable descriptor.
  48          */
  49 -       slave_config.dst_addr = (u32)(dma_reg_base + BCM2835_SPI_FIFO);
  50 +       slave_config.dst_addr = bs->phys_addr + BCM2835_SPI_FIFO;
  51         slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
  52
  53         ret = dmaengine_slave_config(ctlr->dma_tx, &slave_config);
  54 @@ -960,9 +950,9 @@ static int bcm2835_dma_init(struct spi_c
  55          * RX FIFO or, in case of a TX-only transfer, cyclically writes a
  56          * precalculated value to the CS register to clear the RX FIFO.
  57          */
  58 -       slave_config.src_addr = (u32)(dma_reg_base + BCM2835_SPI_FIFO);
  59 +       slave_config.src_addr = bs->phys_addr + BCM2835_SPI_FIFO;
  60         slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
  61 -       slave_config.dst_addr = (u32)(dma_reg_base + BCM2835_SPI_CS);
  62 +       slave_config.dst_addr = bs->phys_addr + BCM2835_SPI_CS;
  63         slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
  64
  65         ret = dmaengine_slave_config(ctlr->dma_rx, &slave_config);
  66 @@ -1335,6 +1325,7 @@ static int bcm2835_spi_probe(struct plat
  67  {
  68         struct spi_controller *ctlr;
  69         struct bcm2835_spi *bs;
  70 +       struct resource *iomem;
  71         int err;
  72
  73         ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*bs));
  74 @@ -1357,10 +1348,11 @@ static int bcm2835_spi_probe(struct plat
  75         bs = spi_controller_get_devdata(ctlr);
  76         bs->ctlr = ctlr;
  77
  78 -       bs->regs = devm_platform_ioremap_resource(pdev, 0);
  79 +       bs->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &iomem);
  80         if (IS_ERR(bs->regs))
  81                 return PTR_ERR(bs->regs);
  82
  83 +       bs->phys_addr = iomem->start;
  84         bs->clk = devm_clk_get(&pdev->dev, NULL);
  85         if (IS_ERR(bs->clk))
  86                 return dev_err_probe(&pdev->dev, PTR_ERR(bs->clk),