diff options
Diffstat (limited to 'src/southbridge/amd')
| -rw-r--r-- | src/southbridge/amd/agesa/hudson/Makefile.inc | 2 | ||||
| -rw-r--r-- | src/southbridge/amd/agesa/hudson/smbus_spd.c | 152 |
2 files changed, 153 insertions, 1 deletions
diff --git a/src/southbridge/amd/agesa/hudson/Makefile.inc b/src/southbridge/amd/agesa/hudson/Makefile.inc index 6ed0ff646f..eb02936b29 100644 --- a/src/southbridge/amd/agesa/hudson/Makefile.inc +++ b/src/southbridge/amd/agesa/hudson/Makefile.inc @@ -30,7 +30,7 @@ INCLUDES += -Isrc/southbridge/amd/agesa/hudson -romstage-y += smbus.c +romstage-y += smbus.c smbus_spd.c ramstage-y += hudson.c ramstage-y += usb.c ramstage-y += lpc.c diff --git a/src/southbridge/amd/agesa/hudson/smbus_spd.c b/src/southbridge/amd/agesa/hudson/smbus_spd.c new file mode 100644 index 0000000000..32e00d6ea6 --- /dev/null +++ b/src/southbridge/amd/agesa/hudson/smbus_spd.c @@ -0,0 +1,152 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2012 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. + * + * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <device/pci_def.h> +#include <device/device.h> + +/* warning: Porting.h includes an open #pragma pack(1) */ +#include "Porting.h" +#include "AGESA.h" +#include "amdlib.h" + +#include <northbridge/amd/agesa/dimmSpd.h> + +/*----------------------------------------------------------------------------- + * + * readSmbusByteData - read a single SPD byte from any offset + */ + +static int readSmbusByteData (int iobase, int address, char *buffer, int offset) +{ + unsigned int status; + UINT64 limit; + + address |= 1; // set read bit + + __outbyte (iobase + 0, 0xFF); // clear error status + __outbyte (iobase + 1, 0x1F); // clear error status + __outbyte (iobase + 3, offset); // offset in eeprom + __outbyte (iobase + 4, address); // slave address and read bit + __outbyte (iobase + 2, 0x48); // read byte command + + // time limit to avoid hanging for unexpected error status (should never happen) + limit = __rdtsc () + 2000000000 / 10; + for (;;) + { + status = __inbyte (iobase); + if (__rdtsc () > limit) break; + if ((status & 2) == 0) continue; // SMBusInterrupt not set, keep waiting + if ((status & 1) == 1) continue; // HostBusy set, keep waiting + break; + } + + buffer [0] = __inbyte (iobase + 5); + if (status == 2) status = 0; // check for done with no errors + return status; +} + +/*----------------------------------------------------------------------------- + * + * readSmbusByte - read a single SPD byte from the default offset + * this function is faster function readSmbusByteData + */ + +static int readSmbusByte (int iobase, int address, char *buffer) +{ + unsigned int status; + UINT64 limit; + + __outbyte (iobase + 0, 0xFF); // clear error status + __outbyte (iobase + 2, 0x44); // read command + + // time limit to avoid hanging for unexpected error status + limit = __rdtsc () + 2000000000 / 10; + for (;;) + { + status = __inbyte (iobase); + if (__rdtsc () > limit) break; + if ((status & 2) == 0) continue; // SMBusInterrupt not set, keep waiting + if ((status & 1) == 1) continue; // HostBusy set, keep waiting + break; + } + + buffer [0] = __inbyte (iobase + 5); + if (status == 2) status = 0; // check for done with no errors + return status; +} + +/*--------------------------------------------------------------------------- + * + * 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 (int iobase, int SmbusSlaveAddress, char *buffer, int count) +{ + int index, error; + + printk(BIOS_SPEW, "-------------READING SPD-----------\n"); + printk(BIOS_SPEW, "iobase: 0x%08X, SmbusSlave: 0x%08X, count: %d\n", + iobase, SmbusSlaveAddress, count); + + /* read the first byte using offset zero */ + error = readSmbusByteData (iobase, SmbusSlaveAddress, buffer, 0); + + if (error) { + printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n"); + return error; + } + + /* read the remaining bytes using auto-increment for speed */ + for (index = 1; index < count; index++) + { + error = readSmbusByte (iobase, SmbusSlaveAddress, &buffer [index]); + if (error) { + printk(BIOS_ERR, "-------------SPD READ ERROR-----------\n"); + return error; + } + } + printk(BIOS_SPEW, "\n"); + printk(BIOS_SPEW, "-------------FINISHED READING SPD-----------\n"); + + return 0; +} + +static void writePmReg (int reg, int data) +{ + __outbyte (0xCD6, reg); + __outbyte (0xCD7, data); +} + +static void setupFch (int ioBase) +{ + writePmReg (0x2D, ioBase >> 8); + writePmReg (0x2C, ioBase | 1); + __outbyte (ioBase + 0x0E, 66000000 / 400000 / 4); // set SMBus clock to 400 KHz +} + +int hudson_readSpd(int spdAddress, char *buf, size_t len) +{ + int ioBase = 0xB00; + setupFch (ioBase); + return readspd (ioBase, spdAddress, buf, len); +} |