vboot: add macros, enums, and struct for EC-EFS2

This CL defines new macros, an enum and a data structure for EC-EFS2
implementation.

BUG=b:141143112
BRANCH=cr50
TEST=make buildall -j

Change-Id: I0b5d634f8e040638b4c4ffef5c8519959c509577
Signed-off-by: Namyoon Woo <namyoon@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1956158

1 files changed, 65 insertions, 0 deletions

diff --git a/include/vboot.h b/include/vboot.h
index d757d0a3e7..7760af569f 100644
--- a/include/vboot.h
+++ b/include/vboot.h
@@ -2,11 +2,74 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
+#ifndef __CROS_EC_INCLUDE_VBOOT_H
+#define __CROS_EC_INCLUDE_VBOOT_H
 
 #include "common.h"
 #include "vb21_struct.h"
 #include "rsa.h"
 
+#define CR50_COMM_PREAMBLE              0xec
+#define MIN_LENGTH_PREAMBLE             4
+#define CR50_COMM_MAGIC_CHAR0           'E'
+#define CR50_COMM_MAGIC_CHAR1           'C'
+#define CR50_COMM_MAGIC_WORD            ((CR50_COMM_MAGIC_CHAR1 << 8) | \
+					 CR50_COMM_MAGIC_CHAR0)
+
+/*
+ * EC-Cr50 data stream looks like as follows:
+ *
+ *   [preamble][header][payload]
+ *
+ * preamble: CR50_COMM_PREAMBLE (at least MIN_LENGTH_PREAMBLE times)
+ * header: struct cr50_comm_packet
+ * payload: data[]
+ */
+struct cr50_comm_packet {
+	/* Header */
+	uint16_t magic;	/* CR50_COMM_MAGIC_WORD */
+	uint8_t crc;	/* checksum computed from all bytes after crc */
+	uint16_t cmd;	/* CR50_COMM_CMD_* if it is sent by EC. */
+			/* CR50_COMM_RESPONSE(X) if it is sent by CR50. */
+	uint8_t size;	/* size of 'data[]' member. */
+	uint8_t data[];	/* payload */
+} __packed;
+
+#define CR50_COMM_MAX_DATA_SIZE         32
+#define CR50_COMM_MAX_PACKET_SIZE       (sizeof(struct cr50_comm_packet) + \
+					 CR50_COMM_MAX_DATA_SIZE)
+
+/* EC-CR50 commands (2 bytes) for cr50_comm_packet.cmd */
+#define CR50_COMM_CMD_SET_BOOT_MODE     0x0001
+#define CR50_COMM_CMD_VERIFY_HASH       0x0002
+
+/* EC-CR50 response codes (2 bytes) for cr50_comm_packet.cmd */
+#define CR50_COMM_RESPONSE(X)           ((CR50_COMM_PREAMBLE << 8) | \
+					 ((X) & 0xff))
+#define CR50_COMM_SUCCESS               CR50_COMM_RESPONSE(0x00)
+#define CR50_COMM_ERROR_UNKNOWN         CR50_COMM_RESPONSE(0x01)
+#define CR50_COMM_ERROR_MAGIC           CR50_COMM_RESPONSE(0x02)
+#define CR50_COMM_ERROR_CRC             CR50_COMM_RESPONSE(0x03)
+#define CR50_COMM_ERROR_SIZE            CR50_COMM_RESPONSE(0x04)
+#define CR50_COMM_ERROR_TIMEOUT         CR50_COMM_RESPONSE(0x05)
+#define CR50_COMM_ERROR_HASH_MISMATCH   CR50_COMM_RESPONSE(0x06)
+#define CR50_COMM_ERROR_UNDEFINED_CMD   CR50_COMM_RESPONSE(0x07)
+
+/*
+ * BIT(1) : NO_BOOT flag
+ * BIT(0) : RECOVERY flag
+ */
+enum ec_efs_boot_mode {
+	EC_EFS_BOOT_MODE_NORMAL           = 0x00,
+	EC_EFS_BOOT_MODE_RECOVERY         = 0x01,
+	EC_EFS_BOOT_MODE_NO_BOOT          = 0x02,
+	EC_EFS_BOOT_MODE_NO_BOOT_RECOVERY = 0x03,
+	EC_EFS_BOOT_MODE_RESET            = 0xff,
+
+	/* boot_mode is uint8_t */
+	EC_EFS_BOOT_MODE_LIMIT            = 255,
+};
+
 /**
  * Validate key contents.
  *
@@ -58,3 +121,5 @@ void vboot_main(void);
  * @return 1: need PD communication. 0: PD communication is not needed.
  */
 int vboot_need_pd_comm(void);
+
+#endif  /* __CROS_EC_INCLUDE_VBOOT_H */