1 files changed, 76 insertions, 0 deletions
diff --git a/board/cr50/ec_efs.c b/board/cr50/ec_efs.c
new file mode 100644
index 0000000000..da5a31f019
--- /dev/null
+++ b/board/cr50/ec_efs.c
@@ -0,0 +1,76 @@
+/* Copyright 2020 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * EC-EFS (Early Firmware Selection)
+ */
+#include "common.h"
+#include "console.h"
+#include "ec_comm.h"
+#include "ec_commands.h"
+#include "hooks.h"
+#include "registers.h"
+#include "system.h"
+#include "vboot.h"
+
+#ifdef CR50_DEV
+#define CPRINTS(format, args...) cprints(CC_TASK, "EC-EFS: " format, ## args)
+#else
+#define CPRINTS(format, args...) do { } while (0)
+#endif
+
+/*
+ * Context of EC-EFS
+ */
+static struct ec_efs_context_ {
+	uint32_t boot_mode:8;	        /* enum ec_efs_boot_mode */
+	uint32_t hash_is_loaded:1;	/* Is EC hash loaded from nvmem */
+	uint32_t reserved:23;
+
+	uint32_t secdata_error_code;
+
+	uint8_t hash[SHA256_DIGEST_SIZE];	/* EC-RW digest */
+} ec_efs_ctx;
+
+/*
+ * Change the boot mode
+ *
+ * @param mode_val New boot mode value to change
+ */
+static void set_boot_mode_(uint8_t mode_val)
+{
+	CPRINTS("boot_mode: 0x%02x -> 0x%02x", ec_efs_ctx.boot_mode, mode_val);
+
+	ec_efs_ctx.boot_mode = mode_val;
+
+	/* Backup some ec_efs context to scratch register */
+	GREG32(PMU, PWRDN_SCRATCH20) &= ~0xff;
+	GREG32(PMU, PWRDN_SCRATCH20) |= mode_val;
+}
+
+/*
+ * Initialize EC-EFS context.
+ */
+static void ec_efs_init_(void)
+{
+	if (!board_has_ec_cr50_comm_support())
+		return;
+
+	/*
+	 * If it is a wakeup from deep sleep, then recover some core EC-EFS
+	 * context values, including the boot_mode value, from a PWRD_SCRATCH
+	 * register. Otherwise, reset boot_mode.
+	 */
+	if (system_get_reset_flags() & EC_RESET_FLAG_HIBERNATE)
+		set_boot_mode_(GREG32(PMU, PWRDN_SCRATCH20) & 0xff);
+	else
+		ec_efs_reset();
+
+	/* TODO(crbug/1020578): Read Hash from Kernel NV Index */
+}
+DECLARE_HOOK(HOOK_INIT, ec_efs_init_, HOOK_PRIO_DEFAULT);
+
+void ec_efs_reset(void)
+{
+	set_boot_mode_(EC_EFS_BOOT_MODE_NORMAL);
+}