linux/arch/riscv/kernel/clint.c

45 lines
945 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2019 Christoph Hellwig.
*/
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/types.h>
#include <asm/clint.h>
#include <asm/csr.h>
#include <asm/timex.h>
#include <asm/smp.h>
/*
* This is the layout used by the SiFive clint, which is also shared by the qemu
* virt platform, and the Kendryte KD210 at least.
*/
#define CLINT_IPI_OFF 0
#define CLINT_TIME_CMP_OFF 0x4000
#define CLINT_TIME_VAL_OFF 0xbff8
u32 __iomem *clint_ipi_base;
void clint_init_boot_cpu(void)
{
struct device_node *np;
void __iomem *base;
np = of_find_compatible_node(NULL, NULL, "riscv,clint0");
if (!np) {
panic("clint not found");
return;
}
base = of_iomap(np, 0);
if (!base)
panic("could not map CLINT");
clint_ipi_base = base + CLINT_IPI_OFF;
riscv_time_cmp = base + CLINT_TIME_CMP_OFF;
riscv_time_val = base + CLINT_TIME_VAL_OFF;
clint_clear_ipi(boot_cpu_hartid);
}