zephyr/arch/arc/core/arc_smp.c

152 lines
3.2 KiB
C

/*
* Copyright (c) 2019 Synopsys.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief codes required for ARC multicore and Zephyr smp support
*
*/
#include <device.h>
#include <kernel.h>
#include <kernel_structs.h>
#include <ksched.h>
#include <soc.h>
#include <init.h>
#ifndef IRQ_ICI
#define IRQ_ICI 19
#endif
#define ARCV2_ICI_IRQ_PRIORITY 1
volatile struct {
arch_cpustart_t fn;
void *arg;
} arc_cpu_init[CONFIG_MP_NUM_CPUS];
/*
* arc_cpu_wake_flag is used to sync up master core and slave cores
* Slave core will spin for arc_cpu_wake_flag until master core sets
* it to the core id of slave core. Then, slave core clears it to notify
* master core that it's waken
*
*/
volatile uint32_t arc_cpu_wake_flag;
volatile char *arc_cpu_sp;
/*
* _curr_cpu is used to record the struct of _cpu_t of each cpu.
* for efficient usage in assembly
*/
volatile _cpu_t *_curr_cpu[CONFIG_MP_NUM_CPUS];
/* Called from Zephyr initialization */
void arch_start_cpu(int cpu_num, k_thread_stack_t *stack, int sz,
arch_cpustart_t fn, void *arg)
{
_curr_cpu[cpu_num] = &(_kernel.cpus[cpu_num]);
arc_cpu_init[cpu_num].fn = fn;
arc_cpu_init[cpu_num].arg = arg;
/* set the initial sp of target sp through arc_cpu_sp
* arc_cpu_wake_flag will protect arc_cpu_sp that
* only one slave cpu can read it per time
*/
arc_cpu_sp = Z_THREAD_STACK_BUFFER(stack) + sz;
arc_cpu_wake_flag = cpu_num;
/* wait slave cpu to start */
while (arc_cpu_wake_flag != 0) {
;
}
}
/* the C entry of slave cores */
void z_arc_slave_start(int cpu_num)
{
arch_cpustart_t fn;
#ifdef CONFIG_SMP
z_icache_setup();
z_irq_setup();
z_arc_connect_ici_clear();
z_irq_priority_set(IRQ_ICI, ARCV2_ICI_IRQ_PRIORITY, 0);
irq_enable(IRQ_ICI);
#endif
/* call the function set by arch_start_cpu */
fn = arc_cpu_init[cpu_num].fn;
fn(arc_cpu_init[cpu_num].arg);
}
#ifdef CONFIG_SMP
static void sched_ipi_handler(void *unused)
{
ARG_UNUSED(unused);
z_arc_connect_ici_clear();
z_sched_ipi();
}
/* arch implementation of sched_ipi */
void arch_sched_ipi(void)
{
uint32_t i;
/* broadcast sched_ipi request to other cores
* if the target is current core, hardware will ignore it
*/
for (i = 0; i < CONFIG_MP_NUM_CPUS; i++) {
z_arc_connect_ici_generate(i);
}
}
static int arc_smp_init(struct device *dev)
{
ARG_UNUSED(dev);
struct arc_connect_bcr bcr;
/* necessary master core init */
_curr_cpu[0] = &(_kernel.cpus[0]);
bcr.val = z_arc_v2_aux_reg_read(_ARC_V2_CONNECT_BCR);
if (bcr.ipi) {
/* register ici interrupt, just need master core to register once */
z_arc_connect_ici_clear();
IRQ_CONNECT(IRQ_ICI, ARCV2_ICI_IRQ_PRIORITY,
sched_ipi_handler, NULL, 0);
irq_enable(IRQ_ICI);
} else {
__ASSERT(0,
"ARC connect has no inter-core interrupt\n");
return -ENODEV;
}
if (bcr.gfrc) {
/* global free running count init */
z_arc_connect_gfrc_enable();
/* when all cores halt, gfrc halt */
z_arc_connect_gfrc_core_set((1 << CONFIG_MP_NUM_CPUS) - 1);
z_arc_connect_gfrc_clear();
} else {
__ASSERT(0,
"ARC connect has no global free running counter\n");
return -ENODEV;
}
return 0;
}
SYS_INIT(arc_smp_init, PRE_KERNEL_1, CONFIG_KERNEL_INIT_PRIORITY_DEFAULT);
#endif