1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/st/iwdg/stm32_iwdg.c b/drivers/st/iwdg/stm32_iwdg.c
new file mode 100644
index 00000000..ea6fbb2b
--- /dev/null
+++ b/drivers/st/iwdg/stm32_iwdg.c
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2017-2019, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+
+#include <libfdt.h>
+
+#include <platform_def.h>
+
+#include <arch_helpers.h>
+#include <common/debug.h>
+#include <drivers/arm/gicv2.h>
+#include <drivers/delay_timer.h>
+#include <drivers/st/stm32_iwdg.h>
+#include <drivers/st/stm32mp_clkfunc.h>
+#include <lib/mmio.h>
+#include <lib/utils.h>
+#include <plat/common/platform.h>
+
+/* IWDG registers offsets */
+#define IWDG_KR_OFFSET		0x00U
+
+/* Registers values */
+#define IWDG_KR_RELOAD_KEY	0xAAAA
+
+struct stm32_iwdg_instance {
+	uintptr_t base;
+	unsigned long clock;
+	uint8_t flags;
+	int num_irq;
+};
+
+static struct stm32_iwdg_instance stm32_iwdg[IWDG_MAX_INSTANCE];
+
+static int stm32_iwdg_get_dt_node(struct dt_node_info *info, int offset)
+{
+	int node;
+
+	node = dt_get_node(info, offset, DT_IWDG_COMPAT);
+	if (node < 0) {
+		if (offset == -1) {
+			VERBOSE("%s: No IDWG found\n", __func__);
+		}
+		return -FDT_ERR_NOTFOUND;
+	}
+
+	return node;
+}
+
+void stm32_iwdg_refresh(void)
+{
+	uint8_t i;
+
+	for (i = 0U; i < IWDG_MAX_INSTANCE; i++) {
+		struct stm32_iwdg_instance *iwdg = &stm32_iwdg[i];
+
+		/* 0x00000000 is not a valid address for IWDG peripherals */
+		if (iwdg->base != 0U) {
+			stm32mp_clk_enable(iwdg->clock);
+
+			mmio_write_32(iwdg->base + IWDG_KR_OFFSET,
+				      IWDG_KR_RELOAD_KEY);
+
+			stm32mp_clk_disable(iwdg->clock);
+		}
+	}
+}
+
+int stm32_iwdg_init(void)
+{
+	int node = -1;
+	struct dt_node_info dt_info;
+	void *fdt;
+	uint32_t __unused count = 0;
+
+	if (fdt_get_address(&fdt) == 0) {
+		panic();
+	}
+
+	for (node = stm32_iwdg_get_dt_node(&dt_info, node);
+	     node != -FDT_ERR_NOTFOUND;
+	     node = stm32_iwdg_get_dt_node(&dt_info, node)) {
+		struct stm32_iwdg_instance *iwdg;
+		uint32_t hw_init;
+		uint32_t idx;
+
+		count++;
+
+		idx = stm32_iwdg_get_instance(dt_info.base);
+		iwdg = &stm32_iwdg[idx];
+		iwdg->base = dt_info.base;
+		iwdg->clock = (unsigned long)dt_info.clock;
+
+		/* DT can specify low power cases */
+		if (fdt_getprop(fdt, node, "stm32,enable-on-stop", NULL) ==
+		    NULL) {
+			iwdg->flags |= IWDG_DISABLE_ON_STOP;
+		}
+
+		if (fdt_getprop(fdt, node, "stm32,enable-on-standby", NULL) ==
+		    NULL) {
+			iwdg->flags |= IWDG_DISABLE_ON_STANDBY;
+		}
+
+		/* Explicit list of supported bit flags */
+		hw_init = stm32_iwdg_get_otp_config(idx);
+
+		if ((hw_init & IWDG_HW_ENABLED) != 0) {
+			if (dt_info.status == DT_DISABLED) {
+				ERROR("OTP enabled but iwdg%u DT-disabled\n",
+				      idx + 1U);
+				panic();
+			}
+			iwdg->flags |= IWDG_HW_ENABLED;
+		}
+
+		if (dt_info.status == DT_DISABLED) {
+			zeromem((void *)iwdg,
+				sizeof(struct stm32_iwdg_instance));
+			continue;
+		}
+
+		if ((hw_init & IWDG_DISABLE_ON_STOP) != 0) {
+			iwdg->flags |= IWDG_DISABLE_ON_STOP;
+		}
+
+		if ((hw_init & IWDG_DISABLE_ON_STANDBY) != 0) {
+			iwdg->flags |= IWDG_DISABLE_ON_STANDBY;
+		}
+
+		VERBOSE("IWDG%u found, %ssecure\n", idx + 1U,
+			((dt_info.status & DT_NON_SECURE) != 0) ?
+			"non-" : "");
+
+#if defined(IMAGE_BL2)
+		if (stm32_iwdg_shadow_update(idx, iwdg->flags) != BSEC_OK) {
+			return -1;
+		}
+#endif
+	}
+
+	VERBOSE("%u IWDG instance%s found\n", count, (count > 1U) ? "s" : "");
+
+	return 0;
+}