stm32mp1: use device tree to determine board_id OTP

This OTP is filled only for STMicroelectronics boards, therefore the BSEC
device tree node for this should be moved to boards DTS files.
The function that displays this information is also reworked to use this
device tree information and macros.
A potential bug is also corrected to avoid non-null terminated string.

Change-Id: Ie4f268a4afff8cc3d63eb7ea31b4f44c8f488267
Signed-off-by: Yann Gautier <yann.gautier@st.com>
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/tf-a/+/133034
Reviewed-by: CITOOLS <smet-aci-reviews@lists.codex.cro.st.com>
Reviewed-by: CIBUILD <smet-aci-builds@lists.codex.cro.st.com>
Reviewed-by: Lionel DEBIEVE <lionel.debieve@st.com>

Author: Yann-lms

fdts/stm32mp157a-dk1.dts

@@ -306,6 +306,14 @@
 };
 
 /* Security specific */
+&bsec {
+	board_id: board_id@ec {
+		reg = <0xec 0x4>;
+		status = "okay";
+		secure-status = "okay";
+	};
+};
+
 &etzpc {
 	st,decprot = <
 		DECPROT(STM32MP1_ETZPC_USART1_ID, DECPROT_NS_RW, DECPROT_UNLOCK)

fdts/stm32mp157c-ed1.dts

@@ -311,6 +311,14 @@
 };
 
 /* Security specific */
+&bsec {
+	board_id: board_id@ec {
+		reg = <0xec 0x4>;
+		status = "okay";
+		secure-status = "okay";
+	};
+};
+
 &etzpc {
 	st,decprot = <
 		DECPROT(STM32MP1_ETZPC_USART1_ID, DECPROT_NS_RW, DECPROT_UNLOCK)

fdts/stm32mp157c-security.dtsi

@@ -41,9 +41,6 @@
 	spare_ns_ea: spare_ns_ea@ea {
 		reg = <0xea 0x2>;
 	};
-	board_id: board_id@ec {
-		reg = <0xec 0x4>;
-	};
 };
 
 &iwdg2 {

plat/st/stm32mp1/stm32mp1_def.h

@@ -374,7 +374,6 @@ enum ddr_type {
 #define UID2_OTP			U(15)
 #define PACKAGE_OTP			U(16)
 #define HW2_OTP				U(18) /* HW watchdog OTP */
-#define BOARD_OTP			U(59)
 
 /* OTP mask */
 /* DATA0 */
@@ -531,6 +530,7 @@ static inline uint32_t tamp_bkpr(uint32_t idx)
 /*******************************************************************************
  * Device Tree defines
  ******************************************************************************/
+#define DT_BSEC_COMPAT			"st,stm32mp15-bsec"
 #define DT_PWR_COMPAT			"st,stm32mp1-pwr"
 #define DT_RCC_CLK_COMPAT		"st,stm32mp1-rcc"
 #define DT_SYSCFG_COMPAT		"st,stm32mp157-syscfg"

plat/st/stm32mp1/stm32mp1_private.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -17,6 +17,23 @@
 #include <stm32mp_dt.h>
 #include <xlat_tables_v2.h>
 
+/* Internal layout of the 32bit OTP word board_id */
+#define BOARD_ID_BOARD_NB_MASK		GENMASK(31, 16)
+#define BOARD_ID_BOARD_NB_SHIFT		16
+#define BOARD_ID_VARIANT_MASK		GENMASK(15, 12)
+#define BOARD_ID_VARIANT_SHIFT		12
+#define BOARD_ID_REVISION_MASK		GENMASK(11, 8)
+#define BOARD_ID_REVISION_SHIFT		8
+#define BOARD_ID_BOM_MASK		GENMASK(3, 0)
+
+#define BOARD_ID2NB(_id)		(((_id) & BOARD_ID_BOARD_NB_MASK) >> \
+					 BOARD_ID_BOARD_NB_SHIFT)
+#define BOARD_ID2VAR(_id)		(((_id) & BOARD_ID_VARIANT_MASK) >> \
+					 BOARD_ID_VARIANT_SHIFT)
+#define BOARD_ID2REV(_id)		(((_id) & BOARD_ID_REVISION_MASK) >> \
+					 BOARD_ID_REVISION_SHIFT)
+#define BOARD_ID2BOM(_id)		((_id) & BOARD_ID_BOM_MASK)
+
 #define MAP_ROM		MAP_REGION_FLAT(STM32MP_ROM_BASE, \
 					STM32MP_ROM_SIZE, \
 					MT_MEMORY | \
@@ -237,23 +254,49 @@ void stm32mp_print_cpuinfo(void)
 
 void stm32mp_print_boardinfo(void)
 {
-	uint32_t board;
-	int res = 0;
+	uint32_t board_id = 0;
+	uint32_t board_otp;
+	int bsec_node, bsec_board_id_node;
+	void *fdt;
+	const fdt32_t *cuint;
+
+	if (fdt_get_address(&fdt) == 0) {
+		panic();
+	}
+
+	bsec_node = fdt_node_offset_by_compatible(fdt, -1, DT_BSEC_COMPAT);
+	if (bsec_node < 0) {
+		return;
+	}
+
+	bsec_board_id_node = fdt_subnode_offset(fdt, bsec_node, "board_id");
+	if (bsec_board_id_node <= 0) {
+		return;
+	}
+
+	cuint = fdt_getprop(fdt, bsec_board_id_node, "reg", NULL);
+	if (cuint == NULL) {
+		ERROR("board_id node without reg property\n");
+		panic();
+	}
+
+	board_otp = fdt32_to_cpu(*cuint) / sizeof(uint32_t);
 
-	if (bsec_shadow_read_otp(&board, BOARD_OTP) != BSEC_OK) {
+	if (bsec_shadow_read_otp(&board_id, board_otp) != BSEC_OK) {
 		ERROR("BSEC: PART_NUMBER_OTP Error\n");
-		res = -1;
+		return;
 	}
 
-	if ((res == 0) && (board != 0U)) {
-		char rev[1];
+	if (board_id != 0U) {
+		char rev[2];
 
-		*rev = ((board >> 8) & 0xF) - 1 + 'A';
+		rev[0] = BOARD_ID2REV(board_id) - 1 + 'A';
+		rev[1] = '\0';
 		NOTICE("Board: MB%04x Var%d Rev.%s-%02d\n",
-		       board >> 16,
-		       (board >> 12) & 0xF,
+		       BOARD_ID2NB(board_id),
+		       BOARD_ID2VAR(board_id),
 		       rev,
-		       board & 0xF);
+		       BOARD_ID2BOM(board_id));
 	}
 }