diff options
Diffstat (limited to 'src/southbridge/amd/sb600/smbus.c')
-rw-r--r-- | src/southbridge/amd/sb600/smbus.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/src/southbridge/amd/sb600/smbus.c b/src/southbridge/amd/sb600/smbus.c new file mode 100644 index 0000000000..cdd1930b5f --- /dev/null +++ b/src/southbridge/amd/sb600/smbus.c @@ -0,0 +1,214 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2008 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 "smbus.h" + +static inline void smbus_delay(void) +{ + outb(0x80, 0x80); +} + +static int smbus_wait_until_ready(u32 smbus_io_base) +{ + u32 loops; + loops = SMBUS_TIMEOUT; + do { + u8 val; + val = inb(smbus_io_base + SMBHSTSTAT); + val &= 0x1f; + if (val == 0) { /* ready now */ + return 0; + } + outb(val, smbus_io_base + SMBHSTSTAT); + } while (--loops); + return -2; /* time out */ +} + +static int smbus_wait_until_done(u32 smbus_io_base) +{ + u32 loops; + loops = SMBUS_TIMEOUT; + do { + u8 val; + + val = inb(smbus_io_base + SMBHSTSTAT); + val &= 0x1f; /* mask off reserved bits */ + if (val & 0x1c) { + return -5; /* error */ + } + if (val == 0x02) { + outb(val, smbus_io_base + SMBHSTSTAT); /* clear status */ + return 0; + } + } while (--loops); + return -3; /* timeout */ +} + +int do_smbus_recv_byte(u32 smbus_io_base, u32 device) +{ + u8 byte; + + if (smbus_wait_until_ready(smbus_io_base) < 0) { + return -2; /* not ready */ + } + + /* set the device I'm talking too */ + outb(((device & 0x7f) << 1) | 1, smbus_io_base + SMBHSTADDR); + + byte = inb(smbus_io_base + SMBHSTCTRL); + byte &= 0xe3; /* Clear [4:2] */ + byte |= (1 << 2) | (1 << 6); /* Byte data read/write command, start the command */ + outb(byte, smbus_io_base + SMBHSTCTRL); + + /* poll for transaction completion */ + if (smbus_wait_until_done(smbus_io_base) < 0) { + return -3; /* timeout or error */ + } + + /* read results of transaction */ + byte = inb(smbus_io_base + SMBHSTCMD); + + return byte; +} + +int do_smbus_send_byte(u32 smbus_io_base, u32 device, u8 val) +{ + u8 byte; + + if (smbus_wait_until_ready(smbus_io_base) < 0) { + return -2; /* not ready */ + } + + /* set the command... */ + outb(val, smbus_io_base + SMBHSTCMD); + + /* set the device I'm talking too */ + outb(((device & 0x7f) << 1) | 0, smbus_io_base + SMBHSTADDR); + + byte = inb(smbus_io_base + SMBHSTCTRL); + byte &= 0xe3; /* Clear [4:2] */ + byte |= (1 << 2) | (1 << 6); /* Byte data read/write command, start the command */ + outb(byte, smbus_io_base + SMBHSTCTRL); + + /* poll for transaction completion */ + if (smbus_wait_until_done(smbus_io_base) < 0) { + return -3; /* timeout or error */ + } + + return 0; +} + +int do_smbus_read_byte(u32 smbus_io_base, u32 device, u32 address) +{ + u8 byte; + + if (smbus_wait_until_ready(smbus_io_base) < 0) { + return -2; /* not ready */ + } + + /* set the command/address... */ + outb(address & 0xff, smbus_io_base + SMBHSTCMD); + + /* set the device I'm talking too */ + outb(((device & 0x7f) << 1) | 1, smbus_io_base + SMBHSTADDR); + + byte = inb(smbus_io_base + SMBHSTCTRL); + byte &= 0xe3; /* Clear [4:2] */ + byte |= (1 << 3) | (1 << 6); /* Byte data read/write command, start the command */ + outb(byte, smbus_io_base + SMBHSTCTRL); + + /* poll for transaction completion */ + if (smbus_wait_until_done(smbus_io_base) < 0) { + return -3; /* timeout or error */ + } + + /* read results of transaction */ + byte = inb(smbus_io_base + SMBHSTDAT0); + + return byte; +} + +int do_smbus_write_byte(u32 smbus_io_base, u32 device, u32 address, u8 val) +{ + u8 byte; + + if (smbus_wait_until_ready(smbus_io_base) < 0) { + return -2; /* not ready */ + } + + /* set the command/address... */ + outb(address & 0xff, smbus_io_base + SMBHSTCMD); + + /* set the device I'm talking too */ + outb(((device & 0x7f) << 1) | 0, smbus_io_base + SMBHSTADDR); + + /* output value */ + outb(val, smbus_io_base + SMBHSTDAT0); + + byte = inb(smbus_io_base + SMBHSTCTRL); + byte &= 0xe3; /* Clear [4:2] */ + byte |= (1 << 3) | (1 << 6); /* Byte data read/write command, start the command */ + outb(byte, smbus_io_base + SMBHSTCTRL); + + /* poll for transaction completion */ + if (smbus_wait_until_done(smbus_io_base) < 0) { + return -3; /* timeout or error */ + } + + return 0; +} + +static void alink_ab_indx(u32 reg_space, u32 reg_addr, u32 mask, u32 val) +{ + u32 tmp; + + outl((reg_space & 0x3) << 30 | reg_addr, AB_INDX); + tmp = inl(AB_DATA); + + tmp &= ~mask; + tmp |= val; + + /* printk(BIOS_DEBUG, "about write %x, index=%x", tmp, (reg_space&0x3)<<30 | reg_addr); */ + outl((reg_space & 0x3) << 30 | reg_addr, AB_INDX); /* probably we dont have to do it again. */ + outl(tmp, AB_DATA); +} + +/* space = 0: AX_INDXC, AX_DATAC +* space = 1: AX_INDXP, AX_DATAP + */ +static void alink_ax_indx(u32 space /*c or p? */ , u32 axindc, + u32 mask, u32 val) +{ + u32 tmp; + + /* read axindc to tmp */ + outl(space << 30 | space << 3 | 0x30, AB_INDX); + outl(axindc, AB_DATA); + outl(space << 30 | space << 3 | 0x34, AB_INDX); + tmp = inl(AB_DATA); + + tmp &= ~mask; + tmp |= val; + + /* write tmp */ + outl(space << 30 | space << 3 | 0x30, AB_INDX); + outl(axindc, AB_DATA); + outl(space << 30 | space << 3 | 0x34, AB_INDX); + outl(tmp, AB_DATA); +} |