u-boot/arch/riscv/lib/smp.c
Sean Anderson 40686c394e riscv: Clean up IPI initialization code
The previous IPI code initialized the device whenever the first call was
made to a riscv_*_ipi function. This made it difficult to determine when
the IPI device was initialized. This patch introduces a new function
riscv_init_ipi. It is called once during arch_cpu_init_dm. In SPL, it is
called in spl_invoke_opensbi. Before this point, no riscv_*_ipi functions
should be called.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2020-07-01 15:01:22 +08:00

111 lines
2.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2019 Fraunhofer AISEC,
* Lukas Auer <lukas.auer@aisec.fraunhofer.de>
*/
#include <common.h>
#include <cpu_func.h>
#include <dm.h>
#include <asm/barrier.h>
#include <asm/smp.h>
DECLARE_GLOBAL_DATA_PTR;
static int send_ipi_many(struct ipi_data *ipi, int wait)
{
ofnode node, cpus;
u32 reg;
int ret, pending;
cpus = ofnode_path("/cpus");
if (!ofnode_valid(cpus)) {
pr_err("Can't find cpus node!\n");
return -EINVAL;
}
ofnode_for_each_subnode(node, cpus) {
/* skip if hart is marked as not available in the device tree */
if (!ofnode_is_available(node))
continue;
/* read hart ID of CPU */
ret = ofnode_read_u32(node, "reg", &reg);
if (ret)
continue;
/* skip if it is the hart we are running on */
if (reg == gd->arch.boot_hart)
continue;
if (reg >= CONFIG_NR_CPUS) {
pr_err("Hart ID %d is out of range, increase CONFIG_NR_CPUS\n",
reg);
continue;
}
#ifndef CONFIG_XIP
/* skip if hart is not available */
if (!(gd->arch.available_harts & (1 << reg)))
continue;
#endif
gd->arch.ipi[reg].addr = ipi->addr;
gd->arch.ipi[reg].arg0 = ipi->arg0;
gd->arch.ipi[reg].arg1 = ipi->arg1;
ret = riscv_send_ipi(reg);
if (ret) {
pr_err("Cannot send IPI to hart %d\n", reg);
return ret;
}
if (wait) {
pending = 1;
while (pending) {
ret = riscv_get_ipi(reg, &pending);
if (ret)
return ret;
}
}
}
return 0;
}
void handle_ipi(ulong hart)
{
int ret;
void (*smp_function)(ulong hart, ulong arg0, ulong arg1);
if (hart >= CONFIG_NR_CPUS)
return;
__smp_mb();
smp_function = (void (*)(ulong, ulong, ulong))gd->arch.ipi[hart].addr;
invalidate_icache_all();
/*
* Clear the IPI to acknowledge the request before jumping to the
* requested function.
*/
ret = riscv_clear_ipi(hart);
if (ret) {
pr_err("Cannot clear IPI of hart %ld (error %d)\n", hart, ret);
return;
}
smp_function(hart, gd->arch.ipi[hart].arg0, gd->arch.ipi[hart].arg1);
}
int smp_call_function(ulong addr, ulong arg0, ulong arg1, int wait)
{
struct ipi_data ipi = {
.addr = addr,
.arg0 = arg0,
.arg1 = arg1,
};
return send_ipi_many(&ipi, wait);
}