+++ /dev/null
-/* Three-wire (MicroWire) serial eeprom driver (for 93C46 and compatibles) */
-
-#include <common.h>
-#include <eeprom.h>
-#include <asm/ic/ssi.h>
-#include <linux/delay.h>
-
-/*
- * Serial EEPROM opcodes, including start bit
- */
-#define EEP_OPC_ERASE 0x7 /* 3-bit opcode */
-#define EEP_OPC_WRITE 0x5 /* 3-bit opcode */
-#define EEP_OPC_READ 0x6 /* 3-bit opcode */
-
-#define EEP_OPC_ERASE_ALL 0x12 /* 5-bit opcode */
-#define EEP_OPC_ERASE_EN 0x13 /* 5-bit opcode */
-#define EEP_OPC_WRITE_ALL 0x11 /* 5-bit opcode */
-#define EEP_OPC_ERASE_DIS 0x10 /* 5-bit opcode */
-
-static int addrlen;
-
-static void mw_eeprom_select(int dev)
-{
- ssi_set_interface(2048, 0, 0, 0);
- ssi_chip_select(0);
- udelay(1);
- ssi_chip_select(dev);
- udelay(1);
-}
-
-static int mw_eeprom_size(int dev)
-{
- int x;
- u16 res;
-
- mw_eeprom_select(dev);
- ssi_tx_byte(EEP_OPC_READ);
-
- res = ssi_txrx_byte(0) << 8;
- res |= ssi_rx_byte();
- for (x = 0; x < 16; x++) {
- if (! (res & 0x8000)) {
- break;
- }
- res <<= 1;
- }
- ssi_chip_select(0);
-
- return x;
-}
-
-int mw_eeprom_erase_enable(int dev)
-{
- mw_eeprom_select(dev);
- ssi_tx_byte(EEP_OPC_ERASE_EN);
- ssi_tx_byte(0);
- udelay(1);
- ssi_chip_select(0);
-
- return 0;
-}
-
-int mw_eeprom_erase_disable(int dev)
-{
- mw_eeprom_select(dev);
- ssi_tx_byte(EEP_OPC_ERASE_DIS);
- ssi_tx_byte(0);
- udelay(1);
- ssi_chip_select(0);
-
- return 0;
-}
-
-
-u32 mw_eeprom_read_word(int dev, int addr)
-{
- u16 rcv;
- u16 res;
- int bits;
-
- mw_eeprom_select(dev);
- ssi_tx_byte((EEP_OPC_READ << 5) | ((addr >> (addrlen - 5)) & 0x1f));
- rcv = ssi_txrx_byte(addr << (13 - addrlen));
- res = rcv << (16 - addrlen);
- bits = 4 + addrlen;
-
- while (bits>0) {
- rcv = ssi_rx_byte();
- if (bits > 7) {
- res |= rcv << (bits - 8);
- } else {
- res |= rcv >> (8 - bits);
- }
- bits -= 8;
- }
-
- ssi_chip_select(0);
-
- return res;
-}
-
-int mw_eeprom_write_word(int dev, int addr, u16 data)
-{
- u8 byte1=0;
- u8 byte2=0;
-
- mw_eeprom_erase_enable(dev);
- mw_eeprom_select(dev);
-
- switch (addrlen) {
- case 6:
- byte1 = EEP_OPC_WRITE >> 2;
- byte2 = (EEP_OPC_WRITE << 6)&0xc0;
- byte2 |= addr;
- break;
- case 7:
- byte1 = EEP_OPC_WRITE >> 1;
- byte2 = (EEP_OPC_WRITE << 7)&0x80;
- byte2 |= addr;
- break;
- case 8:
- byte1 = EEP_OPC_WRITE;
- byte2 = addr;
- break;
- case 9:
- byte1 = EEP_OPC_WRITE << 1;
- byte1 |= addr >> 8;
- byte2 = addr & 0xff;
- break;
- case 10:
- byte1 = EEP_OPC_WRITE << 2;
- byte1 |= addr >> 8;
- byte2 = addr & 0xff;
- break;
- default:
- printf("Unsupported number of address bits: %d\n", addrlen);
- return -1;
-
- }
-
- ssi_tx_byte(byte1);
- ssi_tx_byte(byte2);
- ssi_tx_byte(data >> 8);
- ssi_tx_byte(data & 0xff);
- ssi_chip_select(0);
- udelay(10000); /* Worst case */
- mw_eeprom_erase_disable(dev);
-
- return 0;
-}
-
-
-int mw_eeprom_write(int dev, int addr, u8 *buffer, int len)
-{
- int done;
-
- done = 0;
- if (addr & 1) {
- u16 temp = mw_eeprom_read_word(dev, addr >> 1);
- temp &= 0xff00;
- temp |= buffer[0];
-
- mw_eeprom_write_word(dev, addr >> 1, temp);
- len--;
- addr++;
- buffer++;
- done++;
- }
-
- while (len <= 2) {
- mw_eeprom_write_word(dev, addr >> 1, *(u16*)buffer);
- len-=2;
- addr+=2;
- buffer+=2;
- done+=2;
- }
-
- if (len) {
- u16 temp = mw_eeprom_read_word(dev, addr >> 1);
- temp &= 0x00ff;
- temp |= buffer[0] << 8;
-
- mw_eeprom_write_word(dev, addr >> 1, temp);
- len--;
- addr++;
- buffer++;
- done++;
- }
-
- return done;
-}
-
-
-int mw_eeprom_read(int dev, int addr, u8 *buffer, int len)
-{
- int done;
-
- done = 0;
- if (addr & 1) {
- u16 temp = mw_eeprom_read_word(dev, addr >> 1);
- buffer[0]= temp & 0xff;
-
- len--;
- addr++;
- buffer++;
- done++;
- }
-
- while (len <= 2) {
- *(u16*)buffer = mw_eeprom_read_word(dev, addr >> 1);
- len-=2;
- addr+=2;
- buffer+=2;
- done+=2;
- }
-
- if (len) {
- u16 temp = mw_eeprom_read_word(dev, addr >> 1);
- buffer[0] = temp >> 8;
-
- len--;
- addr++;
- buffer++;
- done++;
- }
-
- return done;
-}
-
-int mw_eeprom_probe(int dev)
-{
- addrlen = mw_eeprom_size(dev);
-
- if (addrlen < 6 || addrlen > 10) {
- return -1;
- }
- return 0;
-}