david/ipxe
david
/
ipxe
Archived
1
0
Fork 0
Code

Added write support for three-wire devices (e.g. the RTL8139 EEPROM)

This commit is contained in:
Michael Brown 2006-12-06 19:51:58 +00:00
parent ac401f481d
commit d2bf7abe75
2 changed files with 61 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
src/drivers/nvs/threewire.c
View File

@ -18,6 +18,7 @@
#include <stddef.h>
#include <assert.h>
#include <timer.h>
#include <gpxe/threewire.h>
/** @file
@ -26,7 +27,8 @@
*
*/
/** Read data from three-wire device
/**
* Read data from three-wire device
*
* @v nvs NVS device
* @v address Address from which to read
@ -46,3 +48,41 @@ int threewire_read ( struct nvs_device *nvs, unsigned int address,
return bus->rw ( bus, device, THREEWIRE_READ, address,
NULL, data, len );
}
/**
* Write data to three-wire device
*
* @v nvs NVS device
* @v address Address from which to read
* @v data Data buffer
* @v len Length of data buffer
* @ret rc Return status code
*/
int threewire_write ( struct nvs_device *nvs, unsigned int address,
const void *data, size_t len ) {
struct spi_device *device = nvs_to_spi ( nvs );
struct spi_bus *bus = device->bus;
int rc;
assert ( bus->mode == SPI_MODE_THREEWIRE );
DBG ( "3wire %p writing %d bytes at %04x\n", device, len, address );
/* Enable device for writing */
if ( ( rc = bus->rw ( bus, device, THREEWIRE_EWEN,
THREEWIRE_EWEN_ADDRESS, NULL, NULL, 0 ) ) != 0 )
return rc;
/* Write data */
if ( ( rc = bus->rw ( bus, device, THREEWIRE_WRITE, address,
data, NULL, len ) ) != 0 )
return rc;
/* Our model of an SPI bus doesn't provide a mechanism for
* "assert CS, wait for MISO to become high, so just wait for
* long enough to ensure that the write has completed.
*/
mdelay ( THREEWIRE_WRITE_MDELAY );
return 0;
}

20
src/include/gpxe/threewire.h
View File

@ -11,6 +11,7 @@
*/
#include <gpxe/spi.h>
#include <limits.h>
/**
* @defgroup tcmds Three-wire commands
@ -20,10 +21,28 @@
/** Read data from memory array */
#define THREEWIRE_READ 0x6
/** Write data to memory array */
#define THREEWIRE_WRITE 0x5
/** Write enable */
#define THREEWIRE_EWEN 0x4
/** Address to be used for write enable command */
#define THREEWIRE_EWEN_ADDRESS INT_MAX
/** Time to wait for write cycles to complete
*
* This is sufficient for AT93C46/AT93C56 devices, but may need to be
* increased in future when other devices are added.
*/
#define THREEWIRE_WRITE_MDELAY 10
/** @} */
extern int threewire_read ( struct nvs_device *nvs, unsigned int address,
void *data, size_t len );
extern int threewire_write ( struct nvs_device *nvs, unsigned int address,
const void *data, size_t len );
/**
* @defgroup tdevs Three-wire device types
@ -36,6 +55,7 @@ init_at93cx6 ( struct spi_device *device, unsigned int organisation ) {
device->nvs.block_size = 1;
device->command_len = 3,
device->nvs.read = threewire_read;
device->nvs.write = threewire_write;
}
/**