blob: 60274005ba4ae216f1be320a042c4d19c365674e [file] [log] [blame]
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2012, 2017 Advanced Micro Devices, 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.
*/
#include <amdblocks/agesawrapper.h>
#include <device/pci_def.h>
#include <device/device.h>
#include <soc/southbridge.h>
#include <soc/smbus.h>
#include <amdblocks/dimm_spd.h>
/*
* readspd - Read one or more SPD bytes from a DIMM.
* Start with offset zero and read sequentially.
* Optimization relies on autoincrement to avoid
* sending offset for every byte.
* Reads 128 bytes in 7-8 ms at 400 KHz.
*/
static int readspd(uint16_t iobase, uint8_t SmbusSlaveAddress,
char *buffer, size_t count)
{
uint8_t dev_addr;
size_t index;
int error;
char *pbuf = buffer;
printk(BIOS_SPEW, "-------------READING SPD-----------\n");
printk(BIOS_SPEW, "iobase: 0x%08X, SmbusSlave: 0x%08X, count: %d\n",
iobase, SmbusSlaveAddress, (int)count);
/*
* Convert received device address to the format accepted by
* do_smbus_read_byte and do_smbus_recv_byte.
*/
dev_addr = (SmbusSlaveAddress >> 1);
/* Read the first SPD byte */
error = do_smbus_read_byte(iobase, dev_addr, 0);
if (error < 0) {
printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n");
return error;
} else {
*pbuf = (char) error;
pbuf++;
}
/* Read the remaining SPD bytes using do_smbus_recv_byte for speed */
for (index = 1 ; index < count ; index++) {
error = do_smbus_recv_byte(iobase, dev_addr);
if (error < 0) {
printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n");
return error;
} else {
*pbuf = (char) error;
pbuf++;
}
}
printk(BIOS_SPEW, "\n");
printk(BIOS_SPEW, "-------------FINISHED READING SPD-----------\n");
return 0;
}
static void write_pm_reg(int reg, int data)
{
outb(reg, PM_INDEX);
outb(data, PM_DATA);
}
static void setup_fch(uint16_t ioBase)
{
write_pm_reg(SMB_ASF_IO_BASE, ioBase >> 8);
outb(SMB_SPEED_400KHZ, ioBase + SMBTIMING);
/* Clear all SMBUS status bits */
outb(SMBHST_STAT_CLEAR, ioBase + SMBHSTSTAT);
outb(SMBSLV_STAT_CLEAR, ioBase + SMBSLVSTAT);
}
int sb_read_spd(uint8_t spdAddress, char *buf, size_t len)
{
uint16_t ioBase = SMB_BASE_ADDR;
setup_fch(ioBase);
return readspd(ioBase, spdAddress, buf, len);
}