diff options
Diffstat (limited to 'drivers/atm/nicstarmac.c')
| -rw-r--r-- | drivers/atm/nicstarmac.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/atm/nicstarmac.c b/drivers/atm/nicstarmac.c new file mode 100644 index 000000000..791f69a07 --- /dev/null +++ b/drivers/atm/nicstarmac.c @@ -0,0 +1,244 @@ +// 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 + +#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); + } +} |