ec/google/chromeec: Use common MEC interface

Switch to using the common MEC interface instead of the
Chrome EC specific code.

Tested on a Chell chromebook that has a MEC based Chrome EC
to ensure that the EC interface is still functional.

Change-Id: Idf26e62c2843993c2df2ab8ef157b263a71a97c9
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/29112
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/ec/google/chromeec/Kconfig

@@ -56,6 +56,7 @@ config EC_GOOGLE_CHROMEEC_LPC
 config EC_GOOGLE_CHROMEEC_MEC
 	depends on EC_GOOGLE_CHROMEEC_LPC
 	def_bool n
+	select EC_GOOGLE_COMMON_MEC
 	help
 	  Microchip EC variant for LPC register access.
 

src/ec/google/chromeec/Makefile.inc

@@ -7,26 +7,21 @@ smm-$(CONFIG_EC_GOOGLE_CHROMEEC_BOARDID) += ec_boardid.c
 
 bootblock-y += ec.c
 bootblock-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
-bootblock-$(CONFIG_EC_GOOGLE_CHROMEEC_MEC) += ec_mec.c
 ramstage-y += ec.c crosec_proto.c vstore.c
 ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
 ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
-ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_MEC) += ec_mec.c
 ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_SPI) += ec_spi.c
 smm-y += ec.c crosec_proto.c smihandler.c vstore.c
 smm-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
 smm-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
-smm-$(CONFIG_EC_GOOGLE_CHROMEEC_MEC) += ec_mec.c
 smm-$(CONFIG_EC_GOOGLE_CHROMEEC_SPI) += ec_spi.c
 romstage-y += ec.c crosec_proto.c vstore.c
 romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
 romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
-romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_MEC) += ec_mec.c
 romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_SPI) += ec_spi.c
 verstage-y += ec.c crosec_proto.c vstore.c
 verstage-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
 verstage-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
-verstage-$(CONFIG_EC_GOOGLE_CHROMEEC_MEC) += ec_mec.c
 verstage-$(CONFIG_EC_GOOGLE_CHROMEEC_SPI) += ec_spi.c
 
 ramstage-$(CONFIG_VBOOT) += vboot_storage.c

src/ec/google/chromeec/ec.h

@@ -93,9 +93,6 @@ int google_chromeec_cbi_get_dram_part_num(char *buf, size_t bufsize);
 #define MEC_EMI_RANGE_START EC_HOST_CMD_REGION0
 #define MEC_EMI_RANGE_END   (EC_LPC_ADDR_MEMMAP + EC_MEMMAP_SIZE)
 
-void mec_io_bytes(int write, u16 offset, unsigned int length,
-		  u8 *buf, u8 *csum);
-
 enum usb_charge_mode {
 	USB_CHARGE_MODE_DISABLED,
 	USB_CHARGE_MODE_CHARGE_AUTO,

src/ec/google/chromeec/ec_lpc.c

@@ -18,6 +18,7 @@
 #include <console/console.h>
 #include <delay.h>
 #include <device/pnp.h>
+#include <ec/google/common/mec.h>
 #include <stdint.h>
 #include <stdlib.h>
 
@@ -40,7 +41,9 @@ static void read_bytes(u16 port, unsigned int length, u8 *dest, u8 *csum)
 #if IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC_MEC)
 	/* Access desired range though EMI interface */
 	if (port >= MEC_EMI_RANGE_START && port <= MEC_EMI_RANGE_END) {
-		mec_io_bytes(0, port, length, dest, csum);
+		csum += mec_io_bytes(MEC_IO_READ, MEC_EMI_BASE,
+				     port - MEC_EMI_RANGE_START,
+				     dest, length);
 		return;
 	}
 #endif
@@ -75,7 +78,9 @@ static void write_bytes(u16 port, unsigned int length, u8 *msg, u8 *csum)
 #if IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC_MEC)
 	/* Access desired range though EMI interface */
 	if (port >= MEC_EMI_RANGE_START && port <= MEC_EMI_RANGE_END) {
-		mec_io_bytes(1, port, length, msg, csum);
+		csum += mec_io_bytes(MEC_IO_WRITE, MEC_EMI_BASE,
+				     port - MEC_EMI_RANGE_START,
+				     msg, length);
 		return;
 	}
 #endif

src/ec/google/chromeec/ec_mec.c

@@ -1,125 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2015 Google Inc.  All rights reserved.
- *
- * 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.
- */
-
-#include <arch/io.h>
-#include "ec.h"
-#include "ec_commands.h"
-
-enum {
-	/* 8-bit access */
-	ACCESS_TYPE_BYTE = 0x0,
-	/* 16-bit access */
-	ACCESS_TYPE_WORD = 0x1,
-	/* 32-bit access */
-	ACCESS_TYPE_LONG = 0x2,
-	/*
-	 * 32-bit access, read or write of MEC_EMI_EC_DATA_B3 causes the
-	 * EC data register to be incremented.
-	 */
-	ACCESS_TYPE_LONG_AUTO_INCREMENT = 0x3,
-};
-
-/* EMI registers are relative to base */
-#define MEC_EMI_HOST_TO_EC	(MEC_EMI_BASE + 0)
-#define MEC_EMI_EC_TO_HOST	(MEC_EMI_BASE + 1)
-#define MEC_EMI_EC_ADDRESS_B0	(MEC_EMI_BASE + 2)
-#define MEC_EMI_EC_ADDRESS_B1	(MEC_EMI_BASE + 3)
-#define MEC_EMI_EC_DATA_B0	(MEC_EMI_BASE + 4)
-#define MEC_EMI_EC_DATA_B1	(MEC_EMI_BASE + 5)
-#define MEC_EMI_EC_DATA_B2	(MEC_EMI_BASE + 6)
-#define MEC_EMI_EC_DATA_B3	(MEC_EMI_BASE + 7)
-
-/*
- * cros_ec_lpc_mec_emi_write_address
- *
- * Initialize EMI read / write at a given address.
- *
- * @addr:        Starting read / write address
- * @access_mode: Type of access, typically 32-bit auto-increment
- */
-static void mec_emi_write_address(u16 addr, u8 access_mode)
-{
-	/* Address relative to start of EMI range */
-	addr -= MEC_EMI_RANGE_START;
-	outb((addr & 0xfc) | access_mode, MEC_EMI_EC_ADDRESS_B0);
-	outb((addr >> 8) & 0x7f, MEC_EMI_EC_ADDRESS_B1);
-}
-
-/*
- * mec_io_bytes - Read / write bytes to MEC EMI port
- *
- * @write:   1 on write operation, 0 on read
- * @port:    Base read / write address
- * @length:  Number of bytes to read / write
- * @buf:     Destination / source buffer
- * @csum:    Optional parameter, sums data transferred
- *
- */
-void mec_io_bytes(int write, u16 port, unsigned int length, u8 *buf, u8 *csum)
-{
-	int i = 0;
-	int io_addr;
-	u8 access_mode, new_access_mode;
-
-	if (length == 0)
-		return;
-
-	/*
-	 * Long access cannot be used on misaligned data since reading B0 loads
-	 * the data register and writing B3 flushes it.
-	 */
-	if ((port & 0x3) || (length < 4))
-		access_mode = ACCESS_TYPE_BYTE;
-	else
-		access_mode = ACCESS_TYPE_LONG_AUTO_INCREMENT;
-
-	/* Initialize I/O at desired address */
-	mec_emi_write_address(port, access_mode);
-
-	/* Skip bytes in case of misaligned port */
-	io_addr = MEC_EMI_EC_DATA_B0 + (port & 0x3);
-	while (i < length) {
-		while (io_addr <= MEC_EMI_EC_DATA_B3) {
-			if (write)
-				outb(buf[i], io_addr++);
-			else
-				buf[i] = inb(io_addr++);
-			if (csum)
-				*csum += buf[i];
-
-			port++;
-			/* Extra bounds check in case of misaligned length */
-			if (++i == length)
-				return;
-		}
-
-		/*
-		 * Use long auto-increment access except for misaligned write,
-		 * since writing B3 triggers the flush.
-		 */
-		if (length - i < 4 && write)
-			new_access_mode = ACCESS_TYPE_BYTE;
-		else
-			new_access_mode = ACCESS_TYPE_LONG_AUTO_INCREMENT;
-		if (new_access_mode != access_mode ||
-		    access_mode != ACCESS_TYPE_LONG_AUTO_INCREMENT) {
-			access_mode = new_access_mode;
-			mec_emi_write_address(port, access_mode);
-		}
-
-		/* Access [B0, B3] on each loop pass */
-		io_addr = MEC_EMI_EC_DATA_B0;
-	}
-}