diff options
Diffstat (limited to 'src/northbridge/via/vx900/early_smbus.c')
-rw-r--r-- | src/northbridge/via/vx900/early_smbus.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/src/northbridge/via/vx900/early_smbus.c b/src/northbridge/via/vx900/early_smbus.c new file mode 100644 index 0000000000..f006ce4ebb --- /dev/null +++ b/src/northbridge/via/vx900/early_smbus.c @@ -0,0 +1,194 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2011 Alexandru Gagniuc <mr.nuke.me@gmail.com> + * + * 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, see <http://www.gnu.org/licenses/>. + */ + +#include <device/pci_ids.h> +#include "early_vx900.h" +#include <device/early_smbus.h> + +#include <arch/io.h> +#include <console/console.h> + +/** + * \brief SMBUS IO ports in relation to the base IO port + */ +#define SMBHSTSTAT(base) (u16)(u32)base + 0x0 +#define SMBSLVSTAT(base) (u16)(u32)base + 0x1 +#define SMBHSTCTL(base) (u16)(u32)base + 0x2 +#define SMBHSTCMD(base) (u16)(u32)base + 0x3 +#define SMBXMITADD(base) (u16)(u32)base + 0x4 +#define SMBHSTDAT0(base) (u16)(u32)base + 0x5 +#define SMBHSTDAT1(base) (u16)(u32)base + 0x6 +#define SMBBLKDAT(base) (u16)(u32)base + 0x7 +#define SMBSLVCTL(base) (u16)(u32)base + 0x8 +#define SMBTRNSADD(base) (u16)(u32)base + 0x9 +#define SMBSLVDATA (base) (u16)(u32)base + 0xa + +static void smbus_delays(int delays) +{ + while (delays--) + smbus_delay(); +} + +/** + * Read a byte from the SMBus. + * + * @param dimm The address location of the DIMM on the SMBus. + * @param offset The offset the data is located at. + */ +u8 smbus_read_byte(u32 smbus_dev, u8 addr, u8 offset) +{ + u8 val; + + /* Initialize SMBUS sequence */ + smbus_reset(smbus_dev); + /* Clear host data port. */ + outb(0x00, SMBHSTDAT0(smbus_dev)); + + smbus_wait_until_ready(smbus_dev); + smbus_delays(50); + + /* Actual addr to reg format. */ + addr = (addr << 1); + addr |= 1; /* read command */ + outb(addr, SMBXMITADD(smbus_dev)); + outb(offset, SMBHSTCMD(smbus_dev)); + /* Start transaction, byte data read. */ + outb(0x48, SMBHSTCTL(smbus_dev)); + smbus_wait_until_ready(smbus_dev); + + val = inb(SMBHSTDAT0(smbus_dev)); + return val; +} + +void enable_smbus(void) +{ + device_t dev; + u8 reg8; + u32 smbus_dev = (u32) SMBUS_IO_BASE; + + /* Locate the Power Management control */ + dev = pci_locate_device(PCI_ID(PCI_VENDOR_ID_VIA, + PCI_DEVICE_ID_VIA_VX900_LPC), 0); + + if (dev == PCI_DEV_INVALID) { + die("Power Management Controller not found\n"); + } + + /* + * To use SMBus to manage devices on the system board, it is a must to + * enable SMBus function by setting + * PMU_RXD2[0] (SMBus Controller Enable) to 1. + * And set PMU_RXD0 and PMU_RXD1 (SMBus I/O Base) to an appropriate + * I/O port address, so that all registers in SMBus I/O port can be + * accessed. + */ + + reg8 = pci_read_config8(dev, 0xd2); + /* Enable SMBus controller */ + reg8 |= 1; + /* Set SMBUS clock from 128k source */ + reg8 |= 1 << 2; + pci_write_config8(dev, 0xd2, reg8); + + reg8 = pci_read_config8(dev, 0x94); + /* SMBUS clock from divider of 14.318 MHz */ + reg8 &= ~(1 << 7); + pci_write_config8(dev, 0x94, reg8); + + /* Set SMBus IO base */ + pci_write_config16(dev, 0xd0, SMBUS_IO_BASE); + + /* + * Initialize the SMBus sequence: + */ + /* Clear SMBus host status register */ + smbus_reset(smbus_dev); + /* Clear SMBus host data 0 register */ + outb(0x00, SMBHSTDAT0(smbus_dev)); + + /* Wait for SMBUS */ + smbus_wait_until_ready(smbus_dev); + +} + +static int spd_get_length(u8 spd_byte0) +{ + spd_byte0 &= 0xf; + + switch (spd_byte0) { + case 0x3: + return 256; + case 0x2: + return 176; + case 0x1: + return 128; + default: + break; + } + return 0; +} + +void spd_read(u8 addr, spd_raw_data spd) +{ + u8 reg; + int i, regs; + u32 smbus_dev = SMBUS_IO_BASE; + + reg = smbus_read_byte(smbus_dev, addr, 2); + if (reg != 0x0b) { + printk(BIOS_DEBUG, "SMBUS device %x not a DDR3 module\n", addr); + spd[2] = 0; + return; + } + + reg = smbus_read_byte(smbus_dev, addr, 0); + if ((regs = spd_get_length(reg)) == 0) { + printk(BIOS_INFO, "No DIMM present at %x\n", addr); + spd[2] = 0; + return; + } + + for (i = 0; i < regs; i++) + spd[i] = smbus_read_byte(smbus_dev, addr, i); +} + +void dump_spd_data(spd_raw_data spd) +{ + int len, i; + u8 reg; + + if ((len = spd_get_length(spd[0])) == 0) { + printk(BIOS_DEBUG, "Invalid SPD\n"); + return; + } + + /* + * I originally saw this way to present SPD data in code from VIA. I + * really liked the idea, so here it goes. + */ + print_debug(" 00 01 02 03 04 05 06 07 07 09 0A 0B 0C 0D 0E 0F\n"); + print_debug("---+------------------------------------------------"); + for (i = 0; i < len; i++) { + reg = spd[i]; + if ((i & 0x0f) == 0) + printk(BIOS_DEBUG, "\n%.2x |", i); + printk(BIOS_DEBUG, " %.2x", reg); + } + print_debug("\n"); +} |