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>
This commit is contained in:
Poddar, Sourav 2013-10-07 15:53:01 +05:30 committed by Jagannadha Sutradharudu Teki
parent 62d206dc31
commit 004f15b600
3 changed files with 6 additions and 0 deletions

View File

@ -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;
}

View File

@ -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) {

View File

@ -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;
};
/**