lib: utils: Add simple FDT timer framework

We add simple timer framework which will select and use timer driver
based on details in FDT passed by previous booting stage.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>

lib/utils/timer/fdt_timer_clint.c

@@ -0,0 +1,46 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <sbi_utils/fdt/fdt_helper.h>
+#include <sbi_utils/timer/fdt_timer.h>
+#include <sbi_utils/sys/clint.h>
+
+static int timer_clint_cold_init(void *fdt, int nodeoff,
+				  const struct fdt_match *match)
+{
+	int rc;
+	u32 max_hartid;
+	unsigned long addr;
+
+	rc = fdt_parse_max_hart_id(fdt, &max_hartid);
+	if (rc)
+		return rc;
+
+	rc = fdt_get_node_addr_size(fdt, nodeoff, &addr, NULL);
+	if (rc)
+		return rc;
+
+	/* TODO: We should figure-out CLINT has_64bit_mmio from DT node */
+	return clint_cold_timer_init(addr, max_hartid + 1, TRUE);
+}
+
+static const struct fdt_match timer_clint_match[] = {
+	{ .compatible = "riscv,clint0" },
+	{ },
+};
+
+struct fdt_timer fdt_timer_clint = {
+	.match_table = timer_clint_match,
+	.cold_init = timer_clint_cold_init,
+	.warm_init = clint_warm_timer_init,
+	.exit = NULL,
+	.value = clint_timer_value,
+	.event_stop = clint_timer_event_stop,
+	.event_start = clint_timer_event_start,
+};