aboutsummaryrefslogtreecommitdiff
path: root/src/southbridge/intel/lynxpoint/smbus.h
diff options
context:
space:
mode:
authorAaron Durbin <adurbin@chromium.org>2012-10-30 09:03:43 -0500
committerRonald G. Minnich <rminnich@gmail.com>2013-03-14 01:44:40 +0100
commit76c3700f02f79b49fec30d6ef18d336f122cbf50 (patch)
treecb1c750ef3946e2ae462e1847ec89946579274b2 /src/southbridge/intel/lynxpoint/smbus.h
parentcc86e63e835ab0bceb62215460a13266a791cdd3 (diff)
haswell: Add initial support for Haswell platforms
The Haswell parts use a PCH code named Lynx Point (Series 8). Therefore, the southbridge support is included as well. The basis for this code is the Sandybridge code. Management Engine, IRQ routing, and ACPI still requires more attention, but this is a good starting point. This code partially gets up through the romstage just before training memory on a Haswell reference board. Change-Id: If572d6c21ca051b486b82a924ca0ffe05c4d0ad4 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/2616 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Diffstat (limited to 'src/southbridge/intel/lynxpoint/smbus.h')
-rw-r--r--src/southbridge/intel/lynxpoint/smbus.h100
1 files changed, 100 insertions, 0 deletions
diff --git a/src/southbridge/intel/lynxpoint/smbus.h b/src/southbridge/intel/lynxpoint/smbus.h
new file mode 100644
index 0000000000..81e594942d
--- /dev/null
+++ b/src/southbridge/intel/lynxpoint/smbus.h
@@ -0,0 +1,100 @@
+/*
+ * 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 "pch.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;
+}
+