imx: add status reporting for HAB status

Add functions to report the HAB (High Assurance Boot) status
of e.g. i.MX6 CPUs.

This is taken from

git://git.freescale.com/imx/uboot-imx.git branch imx_v2009.08_3.0.35_4.0.0
cpu/arm_cortexa8/mx6/generic.c
include/asm-arm/arch-mx6/mx6_secure.h

Signed-off-by: Stefano Babic <sbabic@denx.de>
diff --git a/arch/arm/cpu/armv7/mx6/hab.c b/arch/arm/cpu/armv7/mx6/hab.c
new file mode 100644
index 0000000..5187775
--- /dev/null
+++ b/arch/arm/cpu/armv7/mx6/hab.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2010-2013 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hab.h>
+
+/* -------- start of HAB API updates ------------*/
+#define hab_rvt_report_event ((hab_rvt_report_event_t *)HAB_RVT_REPORT_EVENT)
+#define hab_rvt_report_status ((hab_rvt_report_status_t *)HAB_RVT_REPORT_STATUS)
+#define hab_rvt_authenticate_image \
+	((hab_rvt_authenticate_image_t *)HAB_RVT_AUTHENTICATE_IMAGE)
+#define hab_rvt_entry ((hab_rvt_entry_t *)HAB_RVT_ENTRY)
+#define hab_rvt_exit ((hab_rvt_exit_t *)HAB_RVT_EXIT)
+#define hab_rvt_clock_init HAB_RVT_CLOCK_INIT
+
+bool is_hab_enabled(void)
+{
+	struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR;
+	struct fuse_bank *bank = &ocotp->bank[0];
+	struct fuse_bank0_regs *fuse =
+		(struct fuse_bank0_regs *)bank->fuse_regs;
+	uint32_t reg = readl(&fuse->cfg5);
+
+	return (reg & 0x2) == 0x2;
+}
+
+void display_event(uint8_t *event_data, size_t bytes)
+{
+	uint32_t i;
+
+	if (!(event_data && bytes > 0))
+		return;
+
+	for (i = 0; i < bytes; i++) {
+		if (i == 0)
+			printf("\t0x%02x", event_data[i]);
+		else if ((i % 8) == 0)
+			printf("\n\t0x%02x", event_data[i]);
+		else
+			printf(" 0x%02x", event_data[i]);
+	}
+}
+
+int get_hab_status(void)
+{
+	uint32_t index = 0; /* Loop index */
+	uint8_t event_data[128]; /* Event data buffer */
+	size_t bytes = sizeof(event_data); /* Event size in bytes */
+	enum hab_config config = 0;
+	enum hab_state state = 0;
+
+	if (is_hab_enabled())
+		puts("\nSecure boot enabled\n");
+	else
+		puts("\nSecure boot disabled\n");
+
+	/* Check HAB status */
+	if (hab_rvt_report_status(&config, &state) != HAB_SUCCESS) {
+		printf("\nHAB Configuration: 0x%02x, HAB State: 0x%02x\n",
+		       config, state);
+
+		/* Display HAB Error events */
+		while (hab_rvt_report_event(HAB_FAILURE, index, event_data,
+					&bytes) == HAB_SUCCESS) {
+			puts("\n");
+			printf("--------- HAB Event %d -----------------\n",
+			       index + 1);
+			puts("event data:\n");
+			display_event(event_data, bytes);
+			puts("\n");
+			bytes = sizeof(event_data);
+			index++;
+		}
+	}
+	/* Display message if no HAB events are found */
+	else {
+		printf("\nHAB Configuration: 0x%02x, HAB State: 0x%02x\n",
+		       config, state);
+		puts("No HAB Events Found!\n\n");
+	}
+	return 0;
+}
+
+int do_hab_status(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	if ((argc != 1)) {
+		cmd_usage(cmdtp);
+		return 1;
+	}
+
+	get_hab_status();
+
+	return 0;
+}
+
+U_BOOT_CMD(
+		hab_status, CONFIG_SYS_MAXARGS, 1, do_hab_status,
+		"display HAB status",
+		""
+	  );