// SPDX-License-Identifier: GPL-2.0
/*
* this file included by nicstar.c
*/
/*
* nicstarmac.c
* Read this ForeRunner's MAC address from eprom/eeprom
*/
#include <linux/kernel.h>
typedef void __iomem *virt_addr_t;
#define CYCLE_DELAY 5
/*
This was the original definition
#define osp_MicroDelay(microsec) \
do { int _i = 4*microsec; while (--_i > 0) { __SLOW_DOWN_IO; }} while (0)
*/
#define osp_MicroDelay(microsec) {unsigned long useconds = (microsec); \
udelay((useconds));}
/*
* The following tables represent the timing diagrams found in
* the Data Sheet for the Xicor X25020 EEProm. The #defines below
* represent the bits in the NICStAR's General Purpose register
* that must be toggled for the corresponding actions on the EEProm
* to occur.
*/
/* Write Data To EEProm from SI line on rising edge of CLK */
/* Read Data From EEProm on falling edge of CLK */
#define CS_HIGH 0x0002 /* Chip select high */
#define CS_LOW 0x0000 /* Chip select low (active low) */
#define CLK_HIGH 0x0004 /* Clock high */
#define CLK_LOW 0x0000 /* Clock low */
#define SI_HIGH 0x0001 /* Serial input data high */
#define SI_LOW 0x0000 /* Serial input data low */
/* Read Status Register = 0000 0101b */
#if 0
static u_int32_t rdsrtab[] = {
CS_HIGH | CLK_HIGH,
CS_LOW | CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW | SI_HIGH,
CLK_HIGH | SI_HIGH, /* 1 */
CLK_LOW | SI_LOW,
CLK_HIGH, /* 0 */
CLK_LOW | SI_HIGH,
CLK_HIGH | SI_HIGH /* 1 */
};
#endif /* 0 */
/* Read from EEPROM = 0000 0011b */
static u_int32_t readtab[] = {
/*
CS_HIGH | CLK_HIGH,
*/
CS_LOW | CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW,
CLK_HIGH, /* 0 */
CLK_LOW | SI_HIGH,
CLK_HIGH | SI_HIGH, /* 1 */
CLK_LOW | SI_HIGH,
CLK_HIGH | SI_HIGH /* 1 */
};
/* Clock to read from/write to the eeprom */
static u_int32_t clocktab[] = {
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW,
CLK_HIGH,
CLK_LOW
};
#define NICSTAR_REG_WRITE(bs, reg, val) \
while ( readl(bs + STAT) & 0x0200 ) ; \
writel((val),(base)+(reg))
#define NICSTAR_REG_READ(bs, reg) \
readl((base)+(reg))
#define NICSTAR_REG_GENERAL_PURPOSE GP
/*
* This routine will clock the Read_Status_reg function into the X2520
* eeprom, then pull the result from bit 16 of the NicSTaR's General Purpose
* register.
*/
#if 0
u_int32_t nicstar_read_eprom_status(virt_addr_t base)
{
u_int32_t val;
u_int32_t rbyte;
int32_t i, j;
/* Send read instruction */
val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
for (i = 0; i < ARRAY_SIZE(rdsrtab); i++) {
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | rdsrtab[i]));
osp_MicroDelay(CYCLE_DELAY);
}
/* Done sending instruction - now pull data off of bit 16, MSB first */
/* Data clocked out of eeprom on falling edge of clock */
rbyte = 0;
for (i = 7, j = 0; i >= 0; i--) {
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++]));
rbyte |= (((NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE)
& 0x00010000) >> 16) << i);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++]));
osp_MicroDelay(CYCLE_DELAY);
}
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE, 2);
osp_MicroDelay(CYCLE_DELAY);
return rbyte;
}
#endif /* 0 */
/*
* This routine will clock the Read_data function into the X2520
* eeprom, followed by the address to read from, through the NicSTaR's General
* Purpose register.
*/
static u_int8_t read_eprom_byte(virt_addr_t base, u_int8_t offset)
{
u_int32_t val = 0;
int i, j = 0;
u_int8_t tempread = 0;
val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
/* Send READ instruction */
for (i = 0; i < ARRAY_SIZE(readtab); i++) {
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | readtab[i]));
osp_MicroDelay(CYCLE_DELAY);
}
/* Next, we need to send the byte address to read from */
for (i = 7; i >= 0; i--) {
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++] | ((offset >> i) & 1)));
osp_MicroDelay(CYCLE_DELAY);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++] | ((offset >> i) & 1)));
osp_MicroDelay(CYCLE_DELAY);
}
j = 0;
/* Now, we can read data from the eeprom by clocking it in */
for (i = 7; i >= 0; i--) {
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++]));
osp_MicroDelay(CYCLE_DELAY);
tempread |=
(((NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE)
& 0x00010000) >> 16) << i);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | clocktab[j++]));
osp_MicroDelay(CYCLE_DELAY);
}
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE, 2);
osp_MicroDelay(CYCLE_DELAY);
return tempread;
}
static void nicstar_init_eprom(virt_addr_t base)
{
u_int32_t val;
/*
* turn chip select off
*/
val = NICSTAR_REG_READ(base, NICSTAR_REG_GENERAL_PURPOSE) & 0xFFFFFFF0;
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | CS_HIGH | CLK_HIGH));
osp_MicroDelay(CYCLE_DELAY);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | CS_HIGH | CLK_LOW));
osp_MicroDelay(CYCLE_DELAY);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | CS_HIGH | CLK_HIGH));
osp_MicroDelay(CYCLE_DELAY);
NICSTAR_REG_WRITE(base, NICSTAR_REG_GENERAL_PURPOSE,
(val | CS_HIGH | CLK_LOW));
osp_MicroDelay(CYCLE_DELAY);
}
/*
* This routine will be the interface to the ReadPromByte function
* above.
*/
static void
nicstar_read_eprom(virt_addr_t base,
u_int8_t prom_offset, u_int8_t * buffer, u_int32_t nbytes)
{
u_int i;
for (i = 0; i < nbytes; i++) {
buffer[i] = read_eprom_byte(base, prom_offset);
++prom_offset;
osp_MicroDelay(CYCLE_DELAY);
}
}
