zephyr/soc/xtensa/intel_adsp/common/multiprocessing.c

138 lines
3.9 KiB
C

/*
* Copyright (c) 2019 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/device.h>
#include <zephyr/init.h>
#include <zephyr/kernel.h>
#include <zephyr/kernel_structs.h>
#include <zephyr/toolchain.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/sys/sys_io.h>
#include <xtensa/config/core-isa.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(soc_mp, CONFIG_SOC_LOG_LEVEL);
#include <zsr.h>
#include <cavs-idc.h>
#include <soc.h>
#include <zephyr/cache.h>
#include <adsp_shim.h>
#include <adsp_memory.h>
#include <cpu_init.h>
struct cpustart_rec {
uint32_t cpu;
arch_cpustart_t fn;
void *arg;
};
static struct cpustart_rec start_rec;
const uint32_t *z_mp_start_cpu = &start_rec.cpu;
char *z_mp_stack_top;
/* Vestigial silliness: An old mechanism for core startup would embed
* a "manifest" of code to copy to LP-SRAM at startup (vs. the tiny
* trampoline we use here). This was constructed in the linker
* script, and the first word would encode the number of entries. As
* it happens, SOF still emits the code to copy this data, so it needs
* to see this symbol point to a zero.
*/
uint32_t _loader_storage_manifest_start;
/* Simple array of CPUs that are active and available for an IPI. The
* IDC interrupt is ALSO used to bring a CPU out of reset, so we need
* to be absolutely sure we don't try to IPI a CPU that isn't ready to
* start, or else we'll launch it into garbage and crash the DSP.
*/
bool soc_cpus_active[CONFIG_MP_MAX_NUM_CPUS];
#define NOP4 "nop; nop; nop; nop;"
#define NOP32 NOP4 NOP4 NOP4 NOP4 NOP4 NOP4 NOP4 NOP4
#define NOP128 NOP32 NOP32 NOP32 NOP32
/* Tiny assembly stub for calling z_mp_entry() on the auxiliary CPUs.
* Mask interrupts, clear the register window state and set the stack
* pointer. This represents the minimum work required to run C code
* safely.
*
* Note that alignment is absolutely required: the IDC protocol passes
* only the upper 30 bits of the address to the second CPU.
*/
__asm__(".section .text.z_soc_mp_asm_entry, \"x\" \n\t"
".align 4 \n\t"
".global z_soc_mp_asm_entry \n\t"
"z_soc_mp_asm_entry: \n\t"
" movi a0, 0x4002f \n\t" /* WOE | UM | INTLEVEL(max) */
" wsr a0, PS \n\t"
" movi a0, 0 \n\t"
" wsr a0, WINDOWBASE \n\t"
" movi a0, 1 \n\t"
" wsr a0, WINDOWSTART \n\t"
" rsync \n\t"
" movi a1, z_mp_start_cpu \n\t"
" l32i a1, a1, 0 \n\t"
" l32i a1, a1, 0 \n\t"
" rsr a2, PRID \n\t"
" sub a2, a2, a1 \n\t"
" bnez a2, soc_mp_idle \n\t"
" movi a1, z_mp_stack_top \n\t"
" l32i a1, a1, 0 \n\t"
" call4 z_mp_entry \n\t"
"soc_mp_idle: \n\t"
#ifdef CONFIG_XTENSA_WAITI_BUG
NOP128
" isync \n\t"
" extw \n\t"
#endif
" waiti 0 \n\t" /* Power-gating is allowed, we'll exit via reset */
" j soc_mp_idle \n\t");
#undef NOP128
#undef NOP32
#undef NOP4
__imr void z_mp_entry(void)
{
cpu_early_init();
/* Set up the CPU pointer. */
_cpu_t *cpu = &_kernel.cpus[start_rec.cpu];
__asm__ volatile("wsr %0, " ZSR_CPU_STR :: "r"(cpu));
soc_mp_startup(start_rec.cpu);
soc_cpus_active[start_rec.cpu] = true;
start_rec.fn(start_rec.arg);
__ASSERT(false, "arch_start_cpu() handler should never return");
}
bool arch_cpu_active(int cpu_num)
{
return soc_cpus_active[cpu_num];
}
void arch_start_cpu(int cpu_num, k_thread_stack_t *stack, int sz,
arch_cpustart_t fn, void *arg)
{
__ASSERT_NO_MSG(!soc_cpus_active[cpu_num]);
start_rec.cpu = cpu_num;
start_rec.fn = fn;
start_rec.arg = arg;
z_mp_stack_top = Z_KERNEL_STACK_BUFFER(stack) + sz;
soc_start_core(cpu_num);
}
/* Fallback stub for external SOF code */
__imr int cavs_idc_smp_init(const struct device *dev)
{
ARG_UNUSED(dev);
return 0;
}