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authorVladimir Serbinenko <phcoder@gmail.com>2014-08-01 02:49:27 +0200
committerVladimir Serbinenko <phcoder@gmail.com>2014-08-01 17:36:54 +0200
commitcaf1df0278ef743274b7811e0b4bfb58c122ce4e (patch)
tree6a4ce3cba90b16dfe4aa60f210303959a8800aea /src/southbridge/intel/i82801ix/smbus.h
parent2c3f94454dd29532569fd80f954e6289e7ee2fda (diff)
i82801ix: Provide ramstage smbus functions.
Change-Id: Idc62e382a4002274abe6c23d76fe0874c62846c5 Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com> Reviewed-on: http://review.coreboot.org/6433 Tested-by: build bot (Jenkins) Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
Diffstat (limited to 'src/southbridge/intel/i82801ix/smbus.h')
-rw-r--r--src/southbridge/intel/i82801ix/smbus.h45
1 files changed, 45 insertions, 0 deletions
diff --git a/src/southbridge/intel/i82801ix/smbus.h b/src/southbridge/intel/i82801ix/smbus.h
index f215fb4f4d..af95c54ab8 100644
--- a/src/southbridge/intel/i82801ix/smbus.h
+++ b/src/southbridge/intel/i82801ix/smbus.h
@@ -97,3 +97,48 @@ static int do_smbus_read_byte(unsigned smbus_base, unsigned device, unsigned add
}
return byte;
}
+
+#ifndef __PRE_RAM__
+static int do_smbus_write_byte(unsigned smbus_base, unsigned device, unsigned address, unsigned data)
+{
+ unsigned char global_status_register;
+
+ 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) & ~0x01, 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(data, 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 */
+ if (global_status_register != (1 << 1))
+ return SMBUS_ERROR;
+
+ return 0;
+}
+#endif