spi: fspi: dynamically alloc AHB memory

Apply patch from NXP upstream repo to
dynamically allocate AHB memory as needed.

Signed-off-by: Adam Ford <aford173@gmail.com>
Signed-off-by: Han Xu <han.xu@nxp.com>
Link: https://lore.kernel.org/r/20200126140913.2139260-2-aford173@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-nxp-fspi.c b/drivers/spi/spi-nxp-fspi.c
index 00c7899..23abf5a 100644 (file)
--- a/drivers/spi/spi-nxp-fspi.c
+++ b/drivers/spi/spi-nxp-fspi.c
@@ -307,6 +307,7 @@
 
 #define POLL_TOUT              5000
 #define NXP_FSPI_MAX_CHIPSELECT                4
+#define NXP_FSPI_MIN_IOMAP     SZ_4M
 
 struct nxp_fspi_devtype_data {
        unsigned int rxfifo;
@@ -345,6 +346,8 @@ struct nxp_fspi {
        void __iomem *ahb_addr;
        u32 memmap_phy;
        u32 memmap_phy_size;
+       u32 memmap_start;
+       u32 memmap_len;
        struct clk *clk, *clk_en;
        struct device *dev;
        struct completion c;
@@ -657,12 +660,35 @@ static void nxp_fspi_select_mem(struct nxp_fspi *f, struct spi_device *spi)
        f->selected = spi->chip_select;
 }
 
-static void nxp_fspi_read_ahb(struct nxp_fspi *f, const struct spi_mem_op *op)
+static int nxp_fspi_read_ahb(struct nxp_fspi *f, const struct spi_mem_op *op)
 {
+       u32 start = op->addr.val;
        u32 len = op->data.nbytes;
 
+       /* if necessary, ioremap before AHB read */
+       if ((!f->ahb_addr) || start < f->memmap_start ||
+            start + len > f->memmap_start + f->memmap_len) {
+               if (f->ahb_addr)
+                       iounmap(f->ahb_addr);
+
+               f->memmap_start = start;
+               f->memmap_len = len > NXP_FSPI_MIN_IOMAP ?
+                               len : NXP_FSPI_MIN_IOMAP;
+
+               f->ahb_addr = ioremap_wc(f->memmap_phy + f->memmap_start,
+                                        f->memmap_len);
+
+               if (!f->ahb_addr) {
+                       dev_err(f->dev, "failed to alloc memory\n");
+                       return -ENOMEM;
+               }
+       }
+
        /* Read out the data directly from the AHB buffer. */
-       memcpy_fromio(op->data.buf.in, (f->ahb_addr + op->addr.val), len);
+       memcpy_fromio(op->data.buf.in,
+                     f->ahb_addr + start - f->memmap_start, len);
+
+       return 0;
 }
 
 static void nxp_fspi_fill_txfifo(struct nxp_fspi *f,
@@ -822,7 +848,7 @@ static int nxp_fspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
         */
        if (op->data.nbytes > (f->devtype_data->rxfifo - 4) &&
            op->data.dir == SPI_MEM_DATA_IN) {
-               nxp_fspi_read_ahb(f, op);
+               err = nxp_fspi_read_ahb(f, op);
        } else {
                if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
                        nxp_fspi_fill_txfifo(f, op);
@@ -992,9 +1018,8 @@ static int nxp_fspi_probe(struct platform_device *pdev)
 
        /* find the resources - controller memory mapped space */
        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fspi_mmap");
-       f->ahb_addr = devm_ioremap_resource(dev, res);
-       if (IS_ERR(f->ahb_addr)) {
-               ret = PTR_ERR(f->ahb_addr);
+       if (IS_ERR(res)) {
+               ret = PTR_ERR(res);
                goto err_put_ctrl;
        }
 
@@ -1073,6 +1098,9 @@ static int nxp_fspi_remove(struct platform_device *pdev)
 
        mutex_destroy(&f->lock);
 
+       if (f->ahb_addr)
+               iounmap(f->ahb_addr);
+
        return 0;
 }