[uboot] create uboot from github:

repo: https://github.com/u-boot/u-boot
	commit: d80bb749fab53da72c4a0e09b8c2d2aaa3103c91

Change-Id: Ie6434426e1ec15bc08bb1832798e371f3fd5fb29

u-boot-2021.10/arch/riscv/lib/sifive_clint.c

@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020, Sean Anderson <seanga2@gmail.com>
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * U-Boot syscon driver for SiFive's Core Local Interruptor (CLINT).
+ * The CLINT block holds memory-mapped control and status registers
+ * associated with software and timer interrupts.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/global_data.h>
+#include <asm/io.h>
+#include <asm/smp.h>
+#include <linux/err.h>
+
+/* MSIP registers */
+#define MSIP_REG(base, hart)		((ulong)(base) + (hart) * 4)
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int riscv_init_ipi(void)
+{
+	int ret;
+	struct udevice *dev;
+
+	ret = uclass_get_device_by_driver(UCLASS_TIMER,
+					  DM_DRIVER_GET(sifive_clint), &dev);
+	if (ret)
+		return ret;
+
+	gd->arch.clint = dev_read_addr_ptr(dev);
+	if (!gd->arch.clint)
+		return -EINVAL;
+
+	return 0;
+}
+
+int riscv_send_ipi(int hart)
+{
+	writel(1, (void __iomem *)MSIP_REG(gd->arch.clint, hart));
+
+	return 0;
+}
+
+int riscv_clear_ipi(int hart)
+{
+	writel(0, (void __iomem *)MSIP_REG(gd->arch.clint, hart));
+
+	return 0;
+}
+
+int riscv_get_ipi(int hart, int *pending)
+{
+	*pending = readl((void __iomem *)MSIP_REG(gd->arch.clint, hart));
+
+	return 0;
+}