sb/intel/*: Use common SMBus functions

All Intel southbridges implement the same SMBus functions.
This patch replaces all these similar and mostly identical
implementations with a common file.

This also makes i2c block read available to all those southbridges.
If the northbridge has to read a lot of SPD bytes sequentially, using
this function can reduce the time being spent to read SPD five-fold.

Change-Id: I93bb186e04e8c32dff04fc1abe4b5ecbc4c9c962
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/19258
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

5 files changed, 4 insertions, 110 deletions

diff --git a/src/southbridge/intel/i82801ax/Kconfig b/src/southbridge/intel/i82801ax/Kconfig
index 740c69dd00..cade3f5f82 100644
--- a/src/southbridge/intel/i82801ax/Kconfig
+++ b/src/southbridge/intel/i82801ax/Kconfig
@@ -18,3 +18,5 @@ config SOUTHBRIDGE_INTEL_I82801AX
 	select IOAPIC
 	select HAVE_HARD_RESET
 	select USE_WATCHDOG_ON_BOOT
+	select SOUTHBRIDGE_INTEL_COMMON
+	select SOUTHBRIDGE_INTEL_COMMON_SMBUS
diff --git a/src/southbridge/intel/i82801ax/early_smbus.c b/src/southbridge/intel/i82801ax/early_smbus.c
index 2a224bffd6..836721b6a8 100644
--- a/src/southbridge/intel/i82801ax/early_smbus.c
+++ b/src/southbridge/intel/i82801ax/early_smbus.c
@@ -20,8 +20,8 @@
 #include <console/console.h>
 #include <device/pci_ids.h>
 #include <device/pci_def.h>
+#include <southbridge/intel/common/smbus.h>
 #include "i82801ax.h"
-#include "smbus.h"
 
 void enable_smbus(void)
 {
diff --git a/src/southbridge/intel/i82801ax/i82801ax.h b/src/southbridge/intel/i82801ax/i82801ax.h
index c6e505d25b..879c25a835 100644
--- a/src/southbridge/intel/i82801ax/i82801ax.h
+++ b/src/southbridge/intel/i82801ax/i82801ax.h
@@ -90,15 +90,4 @@ int smbus_read_byte(u8 device, u8 address);
 #define SMB_SMI_EN		(1 << 1)
 #define HST_EN			(1 << 0)
 
-/* SMBus I/O registers. */
-#define SMBHSTSTAT		0x0
-#define SMBHSTCTL		0x2
-#define SMBHSTCMD		0x3
-#define SMBXMITADD		0x4
-#define SMBHSTDAT0		0x5
-#define SMBHSTDAT1		0x6
-#define SMBBLKDAT		0x7
-
-#define SMBUS_TIMEOUT		(10 * 1000 * 100)
-
 #endif
diff --git a/src/southbridge/intel/i82801ax/smbus.c b/src/southbridge/intel/i82801ax/smbus.c
index 54fa34f5a2..1e71a984a8 100644
--- a/src/southbridge/intel/i82801ax/smbus.c
+++ b/src/southbridge/intel/i82801ax/smbus.c
@@ -19,8 +19,8 @@
 #include <device/pci.h>
 #include <device/pci_ids.h>
 #include <arch/io.h>
+#include <southbridge/intel/common/smbus.h>
 #include "i82801ax.h"
-#include "smbus.h"
 
 static int lsmbus_read_byte(device_t dev, u8 address)
 {
diff --git a/src/southbridge/intel/i82801ax/smbus.h b/src/southbridge/intel/i82801ax/smbus.h
deleted file mode 100644
index 0ca7d8e282..0000000000
--- a/src/southbridge/intel/i82801ax/smbus.h
+++ /dev/null
@@ -1,97 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2005 Yinghai Lu <yinghailu@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.
- */
-
-#include <device/smbus_def.h>
-#include "i82801ax.h"
-
-int do_smbus_read_byte(u16 smbus_io_base, u8 device, u8 address);
-
-static void smbus_delay(void)
-{
-	inb(0x80);
-}
-
-static int smbus_wait_until_ready(u16 smbus_io_base)
-{
-	unsigned loops = SMBUS_TIMEOUT;
-	unsigned char byte;
-	do {
-		smbus_delay();
-		if (--loops == 0)
-			break;
-		byte = inb(smbus_io_base + SMBHSTSTAT);
-	} while (byte & 1);
-	return loops ? 0 : -1;
-}
-
-static int smbus_wait_until_done(u16 smbus_io_base)
-{
-	unsigned loops = SMBUS_TIMEOUT;
-	unsigned char byte;
-	do {
-		smbus_delay();
-		if (--loops == 0)
-			break;
-		byte = inb(smbus_io_base + SMBHSTSTAT);
-	} while ((byte & 1) || (byte & ~((1 << 6) | (1 << 0))) == 0);
-	return loops ? 0 : -1;
-}
-
-int do_smbus_read_byte(u16 smbus_io_base, u8 device, u8 address)
-{
-	unsigned char global_status_register;
-	unsigned char byte;
-
-	if (smbus_wait_until_ready(smbus_io_base) < 0) {
-		return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
-	}
-	/* Setup transaction */
-	/* Disable interrupts */
-	outb(inb(smbus_io_base + SMBHSTCTL) & (~1), smbus_io_base + SMBHSTCTL);
-	/* Set the device I'm talking too */
-	outb(((device & 0x7f) << 1) | 1, smbus_io_base + SMBXMITADD);
-	/* Set the command/address... */
-	outb(address & 0xff, smbus_io_base + SMBHSTCMD);
-	/* Set up for a byte data read */
-	outb((inb(smbus_io_base + SMBHSTCTL) & 0xe3) | (0x2 << 2),
-	     (smbus_io_base + SMBHSTCTL));
-	/* Clear any lingering errors, so the transaction will run */
-	outb(inb(smbus_io_base + SMBHSTSTAT), smbus_io_base + SMBHSTSTAT);
-
-	/* Clear the data byte... */
-	outb(0, smbus_io_base + SMBHSTDAT0);
-
-	/* Start the command */
-	outb((inb(smbus_io_base + SMBHSTCTL) | 0x40),
-	     smbus_io_base + SMBHSTCTL);
-
-	/* Poll for transaction completion */
-	if (smbus_wait_until_done(smbus_io_base) < 0) {
-		return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
-	}
-
-	global_status_register = inb(smbus_io_base + SMBHSTSTAT);
-
-	/* Ignore the "In Use" status... */
-	global_status_register &= ~(3 << 5);
-
-	/* Read results of transaction */
-	byte = inb(smbus_io_base + SMBHSTDAT0);
-	if (global_status_register != (1 << 1)) {
-		return SMBUS_ERROR;
-	}
-	return byte;
-}