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-rw-r--r--src/ec/google/chromeec/Kconfig20
-rw-r--r--src/ec/google/chromeec/Makefile.inc3
-rw-r--r--src/ec/google/chromeec/ec.c9
-rw-r--r--src/ec/google/chromeec/ec.h1
-rw-r--r--src/ec/google/chromeec/ec_i2c.c159
5 files changed, 190 insertions, 2 deletions
diff --git a/src/ec/google/chromeec/Kconfig b/src/ec/google/chromeec/Kconfig
index ce96da7b99..c3f04997de 100644
--- a/src/ec/google/chromeec/Kconfig
+++ b/src/ec/google/chromeec/Kconfig
@@ -10,9 +10,25 @@ config EC_GOOGLE_API_ROOT
help
Path to the ec API file (ec/ec_commands.h).
+config EC_GOOGLE_CHROMEEC_I2C
+ depends on EC_GOOGLE_CHROMEEC && !EC_GOOGLE_CHROMEEC_LPC
+ bool
+ default y
+ help
+ Google's Chrome EC via I2C bus.
+
+config EC_GOOGLE_CHROMEEC_I2C_BUS
+ depends on EC_GOOGLE_CHROMEEC_I2C
+ hex "I2C bus for Google's Chrome EC"
+
+config EC_GOOGLE_CHROMEEC_I2C_CHIP
+ depends on EC_GOOGLE_CHROMEEC_I2C
+ hex
+ default 0x1e
+
config EC_GOOGLE_CHROMEEC_LPC
- depends on EC_GOOGLE_CHROMEEC
+ depends on EC_GOOGLE_CHROMEEC && ARCH_X86 # Needs Plug-and-play.
bool
- default y if ARCH_X86
+ default y
help
Google Chrome EC via LPC bus.
diff --git a/src/ec/google/chromeec/Makefile.inc b/src/ec/google/chromeec/Makefile.inc
index 5fb258f1a9..5bc9268067 100644
--- a/src/ec/google/chromeec/Makefile.inc
+++ b/src/ec/google/chromeec/Makefile.inc
@@ -1,8 +1,11 @@
ramstage-y += ec.c
+ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
ramstage-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
smm-y += ec.c
+smm-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
smm-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
romstage-y += ec.c
+romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_I2C) += ec_i2c.c
romstage-$(CONFIG_EC_GOOGLE_CHROMEEC_LPC) += ec_lpc.c
CFLAGS += -I $(call strip_quotes,$(CONFIG_EC_GOOGLE_API_ROOT))
diff --git a/src/ec/google/chromeec/ec.c b/src/ec/google/chromeec/ec.c
index d8305292c1..e068bed6dc 100644
--- a/src/ec/google/chromeec/ec.c
+++ b/src/ec/google/chromeec/ec.c
@@ -34,6 +34,15 @@
#include "ec_commands.h"
#include <vendorcode/google/chromeos/chromeos.h>
+uint8_t google_chromeec_calc_checksum(const uint8_t *data, int size)
+{
+ int csum;
+
+ for (csum = 0; size > 0; data++, size--)
+ csum += *data;
+ return (uint8_t)(csum & 0xff);
+}
+
int google_chromeec_kbbacklight(int percent)
{
struct chromeec_command cec_cmd;
diff --git a/src/ec/google/chromeec/ec.h b/src/ec/google/chromeec/ec.h
index c78560f973..a4c196056f 100644
--- a/src/ec/google/chromeec/ec.h
+++ b/src/ec/google/chromeec/ec.h
@@ -32,6 +32,7 @@ int google_ec_running_ro(void);
u16 google_chromeec_get_board_version(void);
#endif
+uint8_t google_chromeec_calc_checksum(const uint8_t *data, int size);
u32 google_chromeec_get_events_b(void);
int google_chromeec_kbbacklight(int percent);
void google_chromeec_post(u8 postcode);
diff --git a/src/ec/google/chromeec/ec_i2c.c b/src/ec/google/chromeec/ec_i2c.c
new file mode 100644
index 0000000000..a13dde6a7b
--- /dev/null
+++ b/src/ec/google/chromeec/ec_i2c.c
@@ -0,0 +1,159 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 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.
+ *
+ * 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 <arch/io.h>
+#include <console/console.h>
+#include <delay.h>
+#include <device/i2c.h>
+#include <stdint.h>
+#include <string.h>
+#include "ec.h"
+#include "ec_commands.h"
+
+/* Command (host->device) format for I2C:
+ * uint8_t version, cmd, len, data[len], checksum;
+ *
+ * Response (device->host) format for I2C:
+ * uint8_t response, len, data[len], checksum;
+ *
+ * Note the location of checksum is different from LPC protocol.
+ *
+ * The length is 8 bit so maximum data size is 0xff.
+ * Any I2C command should fit in 0xff + 4 bytes, and max response length
+ * is 0xff + 3 bytes.
+ */
+#define MAX_I2C_DATA_SIZE (0xff)
+
+typedef struct {
+ uint8_t version;
+ uint8_t command;
+ uint8_t length;
+ uint8_t data[MAX_I2C_DATA_SIZE + 1];
+} EcCommandI2c;
+
+typedef struct {
+ uint8_t response;
+ uint8_t length;
+ uint8_t data[MAX_I2C_DATA_SIZE + 1];
+} EcResponseI2c;
+
+static inline void i2c_dump(int bus, int chip, const uint8_t *data, size_t size)
+{
+#ifdef TRACE_CHROMEEC
+ printk(BIOS_INFO, "i2c: bus=%d, chip=%#x, size=%d, data: ", bus, chip,
+ size);
+ while (size-- > 0) {
+ printk(BIOS_INFO, "%02X ", *data++);
+ }
+ printk(BIOS_INFO, "\n");
+#endif
+}
+
+static int ec_verify_checksum(const EcResponseI2c *resp)
+{
+ size_t size = sizeof(*resp) - sizeof(resp->data) + resp->length;
+ uint8_t calculated = google_chromeec_calc_checksum(
+ (const uint8_t *)resp, size);
+ uint8_t received = resp->data[resp->length];
+ if (calculated != received) {
+ printk(BIOS_ERR, "%s: Unmatch (rx: %#02x, calc: %#02x)\n",
+ __func__, received, calculated);
+ return 0;
+ }
+ return 1;
+}
+
+static void ec_fill_checksum(EcCommandI2c *cmd)
+{
+ size_t size = sizeof(*cmd) - sizeof(cmd->data) + cmd->length;
+ cmd->data[cmd->length] = google_chromeec_calc_checksum(
+ (const uint8_t *)cmd, size);
+}
+
+int google_chromeec_command(struct chromeec_command *cec_command)
+{
+ EcCommandI2c cmd;
+ EcResponseI2c resp;
+ int bus = CONFIG_EC_GOOGLE_CHROMEEC_I2C_BUS;
+ int chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP;
+ size_t size_i2c_cmd = (sizeof(cmd) - sizeof(cmd.data) +
+ cec_command->cmd_size_in + 1),
+ size_i2c_resp = (sizeof(resp) - sizeof(resp.data) +
+ cec_command->cmd_size_out + 1);
+
+ if (cec_command->cmd_size_in > MAX_I2C_DATA_SIZE ||
+ cec_command->cmd_size_out > MAX_I2C_DATA_SIZE) {
+ printk(BIOS_ERR, "%s: Command data size too large (%d,%d)\n",
+ __func__, cec_command->cmd_size_in,
+ cec_command->cmd_size_out);
+ cec_command->cmd_code = EC_RES_INVALID_PARAM;
+ return 1;
+ }
+
+ /* Construct command. */
+ cmd.version = EC_CMD_VERSION0 + cec_command->cmd_version;
+ cmd.command = cec_command->cmd_code;
+ cmd.length = cec_command->cmd_size_in;
+ memcpy(cmd.data, cec_command->cmd_data_in, cmd.length);
+ ec_fill_checksum(&cmd);
+
+ /* Start I2C communication */
+ i2c_dump(bus, chip, (const uint8_t *)&cmd, size_i2c_cmd);
+ if (i2c_write(bus, chip, 0, 0, (uint8_t *)&cmd, size_i2c_cmd) != 0) {
+ printk(BIOS_ERR, "%s: Cannot complete write to i2c-%d:%#x\n",
+ __func__, bus, chip);
+ cec_command->cmd_code = EC_RES_ERROR;
+ return 1;
+ }
+ if (i2c_read(bus, chip, 0, 0, (uint8_t *)&resp, size_i2c_resp) != 0) {
+ printk(BIOS_ERR, "%s: Cannot complete read from i2c-%d:%#x\n",
+ __func__, bus, chip);
+ cec_command->cmd_code = EC_RES_ERROR;
+ return 1;
+ }
+
+ /* Verify and return response */
+ cec_command->cmd_code = resp.response;
+ if (resp.response != EC_RES_SUCCESS) {
+ printk(BIOS_DEBUG, "%s: Received bad result code %d\n",
+ __func__, (int)resp.response);
+ return 1;
+ }
+ if (resp.length > cec_command->cmd_size_out) {
+ printk(BIOS_ERR, "%s: Received len %#02x too large\n",
+ __func__, (int)resp.length);
+ cec_command->cmd_code = EC_RES_INVALID_RESPONSE;
+ return 1;
+ }
+ if (!ec_verify_checksum(&resp)) {
+ cec_command->cmd_code = EC_RES_INVALID_CHECKSUM;
+ return 1;
+ }
+ cec_command->cmd_size_out = resp.length;
+ memcpy(cec_command->cmd_data_out, resp.data, resp.length);
+ return 0;
+}
+
+#ifndef __PRE_RAM__
+u8 google_chromeec_get_event(void)
+{
+ printk(BIOS_ERR, "%s: Not supported.\n", __func__);
+ return 0;
+}
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-28 06:56:15 +0000