stm32mp1: add FUSE command support

Add support of fuse command (read/write/program/sense)
on bank 0 to access to BSEC SAFMEM (4096 OTP bits).

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/drivers/misc/stm32mp_fuse.c b/drivers/misc/stm32mp_fuse.c
new file mode 100644
index 0000000..2d66135
--- /dev/null
+++ b/drivers/misc/stm32mp_fuse.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ */
+
+#include <common.h>
+#include <command.h>
+#include <misc.h>
+#include <errno.h>
+#include <dm/device.h>
+#include <dm/uclass.h>
+
+#define STM32MP_OTP_BANK	0
+
+/*
+ * The 'fuse' command API
+ */
+int fuse_read(u32 bank, u32 word, u32 *val)
+{
+	int ret = 0;
+	struct udevice *dev;
+
+	switch (bank) {
+	case STM32MP_OTP_BANK:
+		ret = uclass_get_device_by_driver(UCLASS_MISC,
+						  DM_GET_DRIVER(stm32mp_bsec),
+						  &dev);
+		if (ret)
+			return ret;
+		ret = misc_read(dev, word * 4 + STM32_BSEC_SHADOW_OFFSET,
+				val, 4);
+		break;
+
+	default:
+		printf("stm32mp %s: wrong value for bank %i\n", __func__, bank);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+int fuse_prog(u32 bank, u32 word, u32 val)
+{
+	struct udevice *dev;
+	int ret;
+
+	switch (bank) {
+	case STM32MP_OTP_BANK:
+		ret = uclass_get_device_by_driver(UCLASS_MISC,
+						  DM_GET_DRIVER(stm32mp_bsec),
+						  &dev);
+		if (ret)
+			return ret;
+		ret = misc_write(dev, word * 4 + STM32_BSEC_OTP_OFFSET,
+				 &val, 4);
+		break;
+
+	default:
+		printf("stm32mp %s: wrong value for bank %i\n", __func__, bank);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+int fuse_sense(u32 bank, u32 word, u32 *val)
+{
+	struct udevice *dev;
+	int ret;
+
+	switch (bank) {
+	case STM32MP_OTP_BANK:
+		ret = uclass_get_device_by_driver(UCLASS_MISC,
+						  DM_GET_DRIVER(stm32mp_bsec),
+						  &dev);
+		if (ret)
+			return ret;
+		ret = misc_read(dev, word * 4 + STM32_BSEC_OTP_OFFSET, val, 4);
+		break;
+
+	default:
+		printf("stm32mp %s: wrong value for bank %i\n", __func__, bank);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+int fuse_override(u32 bank, u32 word, u32 val)
+{
+	struct udevice *dev;
+	int ret;
+
+	switch (bank) {
+	case STM32MP_OTP_BANK:
+		ret = uclass_get_device_by_driver(UCLASS_MISC,
+						  DM_GET_DRIVER(stm32mp_bsec),
+						  &dev);
+		if (ret)
+			return ret;
+		ret = misc_write(dev, word * 4 + STM32_BSEC_SHADOW_OFFSET,
+				 &val, 4);
+		break;
+
+	default:
+		printf("stm32mp %s: wrong value for bank %i\n",
+		       __func__, bank);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}