diff options
author | Martin Roth <gaumless@gmail.com> | 2014-05-21 14:21:22 -0600 |
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committer | Martin Roth <gaumless@gmail.com> | 2014-07-30 19:00:44 +0200 |
commit | 829c41da6cd9d8e9c9244c8c9ea2b181ea5ab930 (patch) | |
tree | e4923fcc360b33e7f441031df55db731119fa508 /src/southbridge/intel/fsp_rangeley/smbus.h | |
parent | 2963ae7fd49c7086ca9c4231f00a94e2f8a33080 (diff) |
southbridge/intel: Add fsp_rangeley support
This adds the southbridge initialization pieces for Intel's Atom C2000
processor (formerly Rangeley). It is intended to be used with the Intel
Atom C2000 FSP and does not contain all of the pieces that would
otherwise be required for initialization.
Change-Id: I416e85bd6e9c9dcf79f97785074135902fdd18b7
Signed-off-by: Martin Roth <gaumless@gmail.com>
Reviewed-on: http://review.coreboot.org/6370
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Diffstat (limited to 'src/southbridge/intel/fsp_rangeley/smbus.h')
-rw-r--r-- | src/southbridge/intel/fsp_rangeley/smbus.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/src/southbridge/intel/fsp_rangeley/smbus.h b/src/southbridge/intel/fsp_rangeley/smbus.h new file mode 100644 index 0000000000..34d2a8c6be --- /dev/null +++ b/src/southbridge/intel/fsp_rangeley/smbus.h @@ -0,0 +1,99 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2005 Yinghai Lu <yinghailu@gmail.com> + * Copyright (C) 2009 coresystems GmbH + * + * 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/smbus_def.h> +#include "soc.h" + +static void smbus_delay(void) +{ + inb(0x80); +} + +static int smbus_wait_until_ready(u16 smbus_base) +{ + unsigned loops = SMBUS_TIMEOUT; + unsigned char byte; + do { + smbus_delay(); + if (--loops == 0) + break; + byte = inb(smbus_base + SMBHSTSTAT); + } while (byte & 1); + return loops ? 0 : -1; +} + +static int smbus_wait_until_done(u16 smbus_base) +{ + unsigned loops = SMBUS_TIMEOUT; + unsigned char byte; + do { + smbus_delay(); + if (--loops == 0) + break; + byte = inb(smbus_base + SMBHSTSTAT); + } while ((byte & 1) || (byte & ~((1 << 6) | (1 << 0))) == 0); + return loops ? 0 : -1; +} + +static int do_smbus_read_byte(unsigned smbus_base, unsigned device, unsigned address) +{ + unsigned char global_status_register; + unsigned char byte; + + 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) | 1, 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(0, 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 */ + byte = inb(smbus_base + SMBHSTDAT0); + if (global_status_register != (1 << 1)) { + return SMBUS_ERROR; + } + return byte; +} |