| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2008 Arastra, Inc. |
| * |
| * 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; version 2 of the License. |
| * |
| * 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. |
| */ |
| |
| /* This code is based on src/southbridge/intel/esb6300/esb6300_smbus.h */ |
| |
| #include <device/smbus_def.h> |
| |
| #define SMBHSTSTAT 0x0 |
| #define SMBHSTCTL 0x2 |
| #define SMBHSTCMD 0x3 |
| #define SMBXMITADD 0x4 |
| #define SMBHSTDAT0 0x5 |
| #define SMBHSTDAT1 0x6 |
| #define SMBBLKDAT 0x7 |
| #define SMBTRNSADD 0x9 |
| #define SMBSLVDATA 0xa |
| #define SMLINK_PIN_CTL 0xe |
| #define SMBUS_PIN_CTL 0xf |
| #define SMBSLVCMD 0x11 |
| |
| #define SMBUS_TIMEOUT (100*1000*10) |
| |
| static void smbus_delay(void) |
| { |
| outb(0x80, 0x80); |
| } |
| |
| static int smbus_wait_until_ready(u32 smbus_io_base) |
| { |
| u32 loops = SMBUS_TIMEOUT; |
| u8 byte; |
| do { |
| smbus_delay(); |
| if (--loops == 0) |
| break; |
| byte = inb(smbus_io_base + SMBHSTSTAT); |
| } while (byte & 1); |
| return loops ? 0 : -1; |
| } |
| |
| static int smbus_wait_until_done(u32 smbus_io_base) |
| { |
| u32 loops = SMBUS_TIMEOUT; |
| u8 byte; |
| do { |
| smbus_delay(); |
| if (--loops == 0) |
| break; |
| byte = inb(smbus_io_base + SMBHSTSTAT); |
| } while ((byte & 1) || (byte & ~((1 << 6)|(1 << 0))) == 0); |
| return loops ? 0 : -1; |
| } |
| |
| static int do_smbus_read_byte(u32 smbus_io_base, u16 device, u8 address) |
| { |
| u8 global_status_register; |
| u8 byte; |
| |
| if (smbus_wait_until_ready(smbus_io_base) < 0) { |
| return SMBUS_WAIT_UNTIL_READY_TIMEOUT; |
| } |
| /* setup transaction */ |
| /* disable interrupts */ |
| outb(inb(smbus_io_base + SMBHSTCTL) & (~1), smbus_io_base + SMBHSTCTL); |
| /* set the device I'm talking too */ |
| outb(((device & 0x7f) << 1) | 1, smbus_io_base + SMBXMITADD); |
| /* set the command/address... */ |
| outb(address & 0xFF, smbus_io_base + SMBHSTCMD); |
| /* set up for a byte data read */ |
| outb((inb(smbus_io_base + SMBHSTCTL) & 0xE3) | (0x2 << 2), smbus_io_base + SMBHSTCTL); |
| /* clear any lingering errors, so the transaction will run */ |
| outb(inb(smbus_io_base + SMBHSTSTAT), smbus_io_base + SMBHSTSTAT); |
| |
| /* clear the data byte...*/ |
| outb(0, smbus_io_base + SMBHSTDAT0); |
| |
| /* start the command */ |
| outb((inb(smbus_io_base + SMBHSTCTL) | 0x40), smbus_io_base + SMBHSTCTL); |
| |
| /* poll for transaction completion */ |
| if (smbus_wait_until_done(smbus_io_base) < 0) { |
| return SMBUS_WAIT_UNTIL_DONE_TIMEOUT; |
| } |
| |
| global_status_register = inb(smbus_io_base + SMBHSTSTAT); |
| |
| /* Ignore the In Use Status... */ |
| global_status_register &= ~(3 << 5); |
| |
| /* read results of transaction */ |
| byte = inb(smbus_io_base + SMBHSTDAT0); |
| if (global_status_register != (1 << 1)) { |
| return SMBUS_ERROR; |
| } |
| return byte; |
| } |
| |
| static int do_smbus_write_byte(unsigned smbus_base, unsigned device, unsigned address, unsigned data) |
| { |
| unsigned char global_status_register; |
| |
| if (smbus_wait_until_ready(smbus_base) < 0) |
| return SMBUS_WAIT_UNTIL_READY_TIMEOUT; |
| |
| /* Setup transaction */ |
| /* Disable interrupts */ |
| outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL); |
| /* Set the device I'm talking too */ |
| outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD); |
| /* Set the command/address... */ |
| outb(address & 0xff, smbus_base + SMBHSTCMD); |
| /* Set up for a byte data read */ |
| outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x2 << 2), |
| (smbus_base + SMBHSTCTL)); |
| /* Clear any lingering errors, so the transaction will run */ |
| outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT); |
| |
| /* Clear the data byte... */ |
| outb(data, smbus_base + SMBHSTDAT0); |
| |
| /* Start the command */ |
| outb((inb(smbus_base + SMBHSTCTL) | 0x40), |
| smbus_base + SMBHSTCTL); |
| |
| /* Poll for transaction completion */ |
| if (smbus_wait_until_done(smbus_base) < 0) |
| return SMBUS_WAIT_UNTIL_DONE_TIMEOUT; |
| |
| global_status_register = inb(smbus_base + SMBHSTSTAT); |
| |
| /* Ignore the "In Use" status... */ |
| global_status_register &= ~(3 << 5); |
| |
| /* Read results of transaction */ |
| if (global_status_register != (1 << 1)) |
| return SMBUS_ERROR; |
| |
| return 0; |
| } |