sf: Enable FDT-based configuration and memory mapping

Enable device tree control of SPI flash, and use this to implement
memory-mapped SPI flash, which is supported on Intel chips.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index b82011d0fd2833301cc4b5df12ce0b1e4edd49e7..111185af17586900b7ff447ead1e0ea9d131ecc4 100644 (file)
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -8,6 +8,7 @@
  */
 
 #include <common.h>
+#include <fdtdec.h>
 #include <malloc.h>
 #include <spi.h>
 #include <spi_flash.h>
@@ -15,6 +16,8 @@
 
 #include "spi_flash_internal.h"
 
+DECLARE_GLOBAL_DATA_PTR;
+
 static void spi_flash_addr(u32 addr, u8 *cmd)
 {
        /* cmd[0] is actual command */
@@ -146,6 +149,10 @@ int spi_flash_cmd_read_fast(struct spi_flash *flash, u32 offset,
 {
        u8 cmd[5];
 
+       /* Handle memory-mapped SPI */
+       if (flash->memory_map)
+               memcpy(data, flash->memory_map + offset, len);
+
        cmd[0] = CMD_READ_ARRAY_FAST;
        spi_flash_addr(offset, cmd);
        cmd[4] = 0x00;
@@ -275,6 +282,34 @@ int spi_flash_cmd_write_status(struct spi_flash *flash, u8 sr)
        return 0;
 }
 
+#ifdef CONFIG_OF_CONTROL
+int spi_flash_decode_fdt(const void *blob, struct spi_flash *flash)
+{
+       fdt_addr_t addr;
+       fdt_size_t size;
+       int node;
+
+       /* If there is no node, do nothing */
+       node = fdtdec_next_compatible(blob, 0, COMPAT_GENERIC_SPI_FLASH);
+       if (node < 0)
+               return 0;
+
+       addr = fdtdec_get_addr_size(blob, node, "memory-map", &size);
+       if (addr == FDT_ADDR_T_NONE) {
+               debug("%s: Cannot decode address\n", __func__);
+               return 0;
+       }
+
+       if (flash->size != size) {
+               debug("%s: Memory map must cover entire device\n", __func__);
+               return -1;
+       }
+       flash->memory_map = (void *)addr;
+
+       return 0;
+}
+#endif /* CONFIG_OF_CONTROL */
+
 /*
  * The following table holds all device probe functions
  *
@@ -391,9 +426,18 @@ struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
                goto err_manufacturer_probe;
        }
 
+#ifdef CONFIG_OF_CONTROL
+       if (spi_flash_decode_fdt(gd->fdt_blob, flash)) {
+               debug("SF: FDT decode error\n");
+               goto err_manufacturer_probe;
+       }
+#endif
        printf("SF: Detected %s with page size ", flash->name);
        print_size(flash->sector_size, ", total ");
-       print_size(flash->size, "\n");
+       print_size(flash->size, "");
+       if (flash->memory_map)
+               printf(", mapped at %p", flash->memory_map);
+       puts("\n");
 
        spi_release_bus(spi);
 

diff --git a/include/fdtdec.h b/include/fdtdec.h
index 5ca84a0c72ff7e87945567aba4debe510118c481..3b363be036acbf6999a7cda4be3cbbbfde2149c7 100644 (file)
--- a/include/fdtdec.h
+++ b/include/fdtdec.h
@@ -86,6 +86,7 @@ enum fdt_compat_id {
        COMPAT_SAMSUNG_EXYNOS_EHCI,     /* Exynos EHCI controller */
        COMPAT_SAMSUNG_EXYNOS_USB_PHY,  /* Exynos phy controller for usb2.0 */
        COMPAT_MAXIM_MAX77686_PMIC,     /* MAX77686 PMIC */
+       COMPAT_GENERIC_SPI_FLASH,       /* Generic SPI Flash chip */
 
        COMPAT_COUNT,
 };

diff --git a/include/spi_flash.h b/include/spi_flash.h
index 030d49cb71c1b66f95d18a65391ece2055396b39..3b6a44edcef6a1e8707ecd20572f191c9f05da46 100644 (file)
--- a/include/spi_flash.h
+++ b/include/spi_flash.h
@@ -39,6 +39,7 @@ struct spi_flash {
        /* Erase (sector) size */
        u32             sector_size;
 
+       void *memory_map;       /* Address of read-only SPI flash access */
        int             (*read)(struct spi_flash *flash, u32 offset,
                                size_t len, void *buf);
        int             (*write)(struct spi_flash *flash, u32 offset,

diff --git a/lib/fdtdec.c b/lib/fdtdec.c
index cffba94bf618671efefd0d86d5e3e27564c999bb..c95c2c28fa8ad114300f0707ec4a36ddd67c9b48 100644 (file)
--- a/lib/fdtdec.c
+++ b/lib/fdtdec.c
@@ -59,6 +59,7 @@ static const char * const compat_names[COMPAT_COUNT] = {
        COMPAT(SAMSUNG_EXYNOS_EHCI, "samsung,exynos-ehci"),
        COMPAT(SAMSUNG_EXYNOS_USB_PHY, "samsung,exynos-usb-phy"),
        COMPAT(MAXIM_MAX77686_PMIC, "maxim,max77686_pmic"),
+       COMPAT(GENERIC_SPI_FLASH, "spi-flash"),
 };
 
 const char *fdtdec_get_compatible(enum fdt_compat_id id)