Files
Linux_Drivers/linux_5.10/arch/riscv/kernel/cpu_ops_spinwait.c
wangliang.wang 4f810186ab [linux] porting cvitek asic chips.
1. update cv182x/cv183x configuration file
	2. update cv181x/cv180x configuration file
	3. update clk driver for cvitek
	4. update dma driver for cvitek
	5. update soc driver for cvitek
	6. porting cvitek ion driver from kernel-4.19
	7. compatible with riscv

Change-Id: Icff9fafe0ebe7d6bab824bbadb952e08bdc66c19
2023-03-10 20:33:10 +08:00

46 lines
1.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2020 Western Digital Corporation or its affiliates.
*/
#include <linux/errno.h>
#include <linux/of.h>
#include <linux/string.h>
#include <asm/cpu_ops.h>
#include <asm/sbi.h>
#include <asm/smp.h>
const struct cpu_operations cpu_ops_spinwait;
static int spinwait_cpu_prepare(unsigned int cpuid)
{
if (!cpu_ops_spinwait.cpu_start) {
pr_err("cpu start method not defined for CPU [%d]\n", cpuid);
return -ENODEV;
}
return 0;
}
static int spinwait_cpu_start(unsigned int cpuid, struct task_struct *tidle)
{
/*
* In this protocol, all cpus boot on their own accord. _start
* selects the first cpu to boot the kernel and causes the remainder
* of the cpus to spin in a loop waiting for their stack pointer to be
* setup by that main cpu. Writing to bootdata
* (i.e __cpu_up_stack_pointer) signals to the spinning cpus that they
* can continue the boot process.
*/
cpu_update_secondary_bootdata(cpuid, tidle);
sbi_ecall(0x09000003, 0, cpuid_to_hartid_map(cpuid), 0, 0, 0, 0, 0);
return 0;
}
const struct cpu_operations cpu_ops_spinwait = {
.name = "spinwait",
.cpu_prepare = spinwait_cpu_prepare,
.cpu_start = spinwait_cpu_start,
};