diff options
Diffstat (limited to 'arch/arm/mach-clps711x/mp1000-seprom.c')
| -rw-r--r-- | arch/arm/mach-clps711x/mp1000-seprom.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/arch/arm/mach-clps711x/mp1000-seprom.c b/arch/arm/mach-clps711x/mp1000-seprom.c new file mode 100644 index 00000000000..b22d0bebb85 --- /dev/null +++ b/arch/arm/mach-clps711x/mp1000-seprom.c @@ -0,0 +1,195 @@ +/*` + * mp1000-seprom.c + * + * This file contains the Serial EEPROM code for the MP1000 board + * + * Copyright (C) 2005 Comdial Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <asm/hardware.h> +#include <asm/hardware/clps7111.h> +#include <asm/arch/mp1000-seprom.h> + +/* If SepromInit() can initialize and checksum the seprom successfully, */ +/* then it will point seprom_data_ptr at the shadow copy. */ + +static eeprom_struct seprom_data; /* shadow copy of seprom content */ + +eeprom_struct *seprom_data_ptr = 0; /* 0 => not initialized */ + +/* + * Port D Bit 5 is Chip Select for EEPROM + * Port E Bit 0 is Input, Data out from EEPROM + * Port E Bit 1 is Output, Data in to EEPROM + * Port E Bit 2 is Output, CLK to EEPROM + */ + +static char *port_d_ptr = (char *)(CLPS7111_VIRT_BASE + PDDR); +static char *port_e_ptr = (char *)(CLPS7111_VIRT_BASE + PEDR); + +#define NO_OF_SHORTS 64 // Device is 64 x 16 bits +#define ENABLE_RW 0 +#define DISABLE_RW 1 + +static inline void toggle_seprom_clock(void) +{ + *port_e_ptr |= HwPortESepromCLK; + *port_e_ptr &= ~(HwPortESepromCLK); +} + +static inline void select_eeprom(void) +{ + *port_d_ptr |= HwPortDEECS; + *port_e_ptr &= ~(HwPortESepromCLK); +} + +static inline void deselect_eeprom(void) +{ + *port_d_ptr &= ~(HwPortDEECS); + *port_e_ptr &= ~(HwPortESepromDIn); +} + +/* + * GetSepromDataPtr - returns pointer to shadow (RAM) copy of seprom + * and returns 0 if seprom is not initialized or + * has a checksum error. + */ + +eeprom_struct* get_seprom_ptr(void) +{ + return seprom_data_ptr; +} + +unsigned char* get_eeprom_mac_address(void) +{ + return seprom_data_ptr->variant.eprom_struct.mac_Address; +} + +/* + * ReadSProm, Physically reads data from the Serial PROM + */ +static void read_sprom(short address, int length, eeprom_struct *buffer) +{ + short data = COMMAND_READ | (address & 0x3F); + short bit; + int i; + + select_eeprom(); + + // Clock in 9 bits of the command + for (i = 0, bit = 0x100; i < 9; i++, bit >>= 1) { + if (data & bit) + *port_e_ptr |= HwPortESepromDIn; + else + *port_e_ptr &= ~(HwPortESepromDIn); + + toggle_seprom_clock(); + } + + // + // Now read one or more shorts of data from the Seprom + // + while (length-- > 0) { + data = 0; + + // Read 16 bits at a time + for (i = 0; i < 16; i++) { + data <<= 1; + toggle_seprom_clock(); + data |= *port_e_ptr & HwPortESepromDOut; + + } + + buffer->variant.eprom_short_data[address++] = data; + } + + deselect_eeprom(); + + return; +} + + + +/* + * ReadSerialPROM + * + * Input: Pointer to array of 64 x 16 Bits + * + * Output: if no problem reading data is filled in + */ +static void read_serial_prom(eeprom_struct *data) +{ + read_sprom(0, 64, data); +} + + +// +// Compute Serial EEPROM checksum +// +// Input: Pointer to struct with Eprom data +// +// Output: The computed Eprom checksum +// +static short compute_seprom_checksum(eeprom_struct *data) +{ + short checksum = 0; + int i; + + for (i = 0; i < 126; i++) { + checksum += (short)data->variant.eprom_byte_data[i]; + } + + return((short)(0x5555 - (checksum & 0xFFFF))); +} + +// +// Make sure the data port bits for the SEPROM are correctly initialised +// + +void __init seprom_init(void) +{ + short checksum; + + // Init Port D + *(char *)(CLPS7111_VIRT_BASE + PDDDR) = 0x0; + *(char *)(CLPS7111_VIRT_BASE + PDDR) = 0x15; + + // Init Port E + *(int *)(CLPS7111_VIRT_BASE + PEDDR) = 0x06; + *(int *)(CLPS7111_VIRT_BASE + PEDR) = 0x04; + + // + // Make sure that EEPROM struct size never exceeds 128 bytes + // + if (sizeof(eeprom_struct) > 128) { + panic("Serial PROM struct size > 128, aborting read\n"); + } + + read_serial_prom(&seprom_data); + + checksum = compute_seprom_checksum(&seprom_data); + + if (checksum != seprom_data.variant.eprom_short_data[63]) { + panic("Serial EEPROM checksum failed\n"); + } + + seprom_data_ptr = &seprom_data; +} + |