sf: Add memory mapped read support

Qspi controller can have a memory mapped port which can be used for
data read. Added support to enable memory mapped port read.

This patch enables the following:
- It enables exchange of memory map address between mtd and qspi
through the introduction of "memory_map" flag.
- Add support to communicate to the driver that memory mapped
 transfer is to be started through introduction of new flags like
"SPI_XFER_MEM_MAP" and "SPI_XFER_MEM_MAP_END".

This will enable the spi controller to do memory mapped configurations
if required.

Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>

diff --git a/drivers/mtd/spi/sf_ops.c b/drivers/mtd/spi/sf_ops.c
index c009af5c208f023805701cf37c192068fc004138..2396e2272fe0abe4aba46ce7f9f15a304c6e4f6f 100644 (file)
--- a/drivers/mtd/spi/sf_ops.c
+++ b/drivers/mtd/spi/sf_ops.c
@@ -269,7 +269,9 @@ int spi_flash_cmd_read_ops(struct spi_flash *flash, u32 offset,
 
        /* Handle memory-mapped SPI */
        if (flash->memory_map) {
+               spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP);
                memcpy(data, flash->memory_map + offset, len);
+               spi_xfer(flash->spi, 0, NULL, NULL, SPI_XFER_MMAP_END);
                return 0;
        }
 

diff --git a/drivers/mtd/spi/sf_probe.c b/drivers/mtd/spi/sf_probe.c
index 15256369e087336b30e2f6274cedf94c01538b0c..6aa7086c41f054a72c10b4827b428d14331d1fa6 100644 (file)
--- a/drivers/mtd/spi/sf_probe.c
+++ b/drivers/mtd/spi/sf_probe.c
@@ -203,6 +203,7 @@ struct spi_flash *spi_flash_validate_params(struct spi_slave *spi, u8 *idcode)
        flash->page_size = (ext_jedec == 0x4d00) ? 512 : 256;
        flash->sector_size = params->sector_size;
        flash->size = flash->sector_size * params->nr_sectors;
+       flash->memory_map = spi->memory_map;
 
        /* Compute erase sector and command */
        if (params->flags & SECT_4K) {

diff --git a/include/spi.h b/include/spi.h
index c44ebe88740ce11f01d44ae2e019c56af2446d6e..c2086fc62e7f25631bbd9a55dc5933e98fbb73c6 100644 (file)
--- a/include/spi.h
+++ b/include/spi.h
@@ -27,6 +27,8 @@
 /* SPI transfer flags */
 #define SPI_XFER_BEGIN 0x01                    /* Assert CS before transfer */
 #define SPI_XFER_END   0x02                    /* Deassert CS after transfer */
+#define SPI_XFER_MMAP  0x08                    /* Memory Mapped start */
+#define SPI_XFER_MMAP_END      0x10            /* Memory Mapped End */
 
 /* Header byte that marks the start of the message */
 #define SPI_PREAMBLE_END_BYTE          0xec
@@ -46,6 +48,7 @@ struct spi_slave {
        unsigned int bus;
        unsigned int cs;
        unsigned int max_write_size;
+       void *memory_map;
 };
 
 /**