Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
/*
 * arch/ia64/kernel/crash.c
 *
 * Architecture specific (ia64) functions for kexec based crash dumps.
 *
 * Created by: Khalid Aziz <khalid.aziz@hp.com>
 * Copyright (C) 2005 Hewlett-Packard Development Company, L.P.
 * Copyright (C) 2005 Intel Corp	Zou Nan hai <nanhai.zou@intel.com>
 *
 */
#include <linux/smp.h>
#include <linux/delay.h>
#include <linux/crash_dump.h>
#include <linux/memblock.h>
#include <linux/kexec.h>
#include <linux/elfcore.h>
#include <linux/sysctl.h>
#include <linux/init.h>
#include <linux/kdebug.h>
 
#include <asm/mca.h>
 
int kdump_status[NR_CPUS];
static atomic_t kdump_cpu_frozen;
atomic_t kdump_in_progress;
static int kdump_freeze_monarch;
static int kdump_on_init = 1;
static int kdump_on_fatal_mca = 1;
 
extern void ia64_dump_cpu_regs(void *);
 
static DEFINE_PER_CPU(struct elf_prstatus, elf_prstatus);
 
void
crash_save_this_cpu(void)
{
<------>void *buf;
<------>unsigned long cfm, sof, sol;
 
<------>int cpu = smp_processor_id();
<------>struct elf_prstatus *prstatus = &per_cpu(elf_prstatus, cpu);
 
<------>elf_greg_t *dst = (elf_greg_t *)&(prstatus->pr_reg);
<------>memset(prstatus, 0, sizeof(*prstatus));
<------>prstatus->pr_pid = current->pid;
 
<------>ia64_dump_cpu_regs(dst);
<------>cfm = dst[43];
<------>sol = (cfm >> 7) & 0x7f;
<------>sof = cfm & 0x7f;
<------>dst[46] = (unsigned long)ia64_rse_skip_regs((unsigned long *)dst[46],
<------><------><------>sof - sol);
 
<------>buf = (u64 *) per_cpu_ptr(crash_notes, cpu);
<------>if (!buf)
<------><------>return;
<------>buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS, prstatus,
<------><------><------>sizeof(*prstatus));
<------>final_note(buf);
}
 
#ifdef CONFIG_SMP
static int
kdump_wait_cpu_freeze(void)
{
<------>int cpu_num = num_online_cpus() - 1;
<------>int timeout = 1000;
<------>while(timeout-- > 0) {
<------><------>if (atomic_read(&kdump_cpu_frozen) == cpu_num)
<------><------><------>return 0;
<------><------>udelay(1000);
<------>}
<------>return 1;
}
#endif
 
void
machine_crash_shutdown(struct pt_regs *pt)
{
<------>/* This function is only called after the system
<------> * has paniced or is otherwise in a critical state.
<------> * The minimum amount of code to allow a kexec'd kernel
<------> * to run successfully needs to happen here.
<------> *
<------> * In practice this means shooting down the other cpus in
<------> * an SMP system.
<------> */
<------>kexec_disable_iosapic();
#ifdef CONFIG_SMP
<------>/*
<------> * If kdump_on_init is set and an INIT is asserted here, kdump will
<------> * be started again via INIT monarch.
<------> */
<------>local_irq_disable();
<------>ia64_set_psr_mc();	/* mask MCA/INIT */
<------>if (atomic_inc_return(&kdump_in_progress) != 1)
<------><------>unw_init_running(kdump_cpu_freeze, NULL);
 
<------>/*
<------> * Now this cpu is ready for kdump.
<------> * Stop all others by IPI or INIT.  They could receive INIT from
<------> * outside and might be INIT monarch, but only thing they have to
<------> * do is falling into kdump_cpu_freeze().
<------> *
<------> * If an INIT is asserted here:
<------> * - All receivers might be slaves, since some of cpus could already
<------> *   be frozen and INIT might be masked on monarch.  In this case,
<------> *   all slaves will be frozen soon since kdump_in_progress will let
<------> *   them into DIE_INIT_SLAVE_LEAVE.
<------> * - One might be a monarch, but INIT rendezvous will fail since
<------> *   at least this cpu already have INIT masked so it never join
<------> *   to the rendezvous.  In this case, all slaves and monarch will
<------> *   be frozen soon with no wait since the INIT rendezvous is skipped
<------> *   by kdump_in_progress.
<------> */
<------>kdump_smp_send_stop();
<------>/* not all cpu response to IPI, send INIT to freeze them */
<------>if (kdump_wait_cpu_freeze()) {
<------><------>kdump_smp_send_init();
<------><------>/* wait again, don't go ahead if possible */
<------><------>kdump_wait_cpu_freeze();
<------>}
#endif
}
 
static void
machine_kdump_on_init(void)
{
<------>crash_save_vmcoreinfo();
<------>local_irq_disable();
<------>kexec_disable_iosapic();
<------>machine_kexec(ia64_kimage);
}
 
void
kdump_cpu_freeze(struct unw_frame_info *info, void *arg)
{
<------>int cpuid;
 
<------>local_irq_disable();
<------>cpuid = smp_processor_id();
<------>crash_save_this_cpu();
<------>current->thread.ksp = (__u64)info->sw - 16;
 
<------>ia64_set_psr_mc();	/* mask MCA/INIT and stop reentrance */
 
<------>atomic_inc(&kdump_cpu_frozen);
<------>kdump_status[cpuid] = 1;
<------>mb();
<------>for (;;)
<------><------>cpu_relax();
}
 
static int
kdump_init_notifier(struct notifier_block *self, unsigned long val, void *data)
{
<------>struct ia64_mca_notify_die *nd;
<------>struct die_args *args = data;
 
<------>if (atomic_read(&kdump_in_progress)) {
<------><------>switch (val) {
<------><------>case DIE_INIT_MONARCH_LEAVE:
<------><------><------>if (!kdump_freeze_monarch)
<------><------><------><------>break;
<------><------><------>fallthrough;
<------><------>case DIE_INIT_SLAVE_LEAVE:
<------><------>case DIE_INIT_MONARCH_ENTER:
<------><------>case DIE_MCA_RENDZVOUS_LEAVE:
<------><------><------>unw_init_running(kdump_cpu_freeze, NULL);
<------><------><------>break;
<------><------>}
<------>}
 
<------>if (!kdump_on_init && !kdump_on_fatal_mca)
<------><------>return NOTIFY_DONE;
 
<------>if (!ia64_kimage) {
<------><------>if (val == DIE_INIT_MONARCH_LEAVE)
<------><------><------>ia64_mca_printk(KERN_NOTICE
<------><------><------><------><------>"%s: kdump not configured\n",
<------><------><------><------><------>__func__);
<------><------>return NOTIFY_DONE;
<------>}
 
<------>if (val != DIE_INIT_MONARCH_LEAVE &&
<------>    val != DIE_INIT_MONARCH_PROCESS &&
<------>    val != DIE_MCA_MONARCH_LEAVE)
<------><------>return NOTIFY_DONE;
 
<------>nd = (struct ia64_mca_notify_die *)args->err;
 
<------>switch (val) {
<------>case DIE_INIT_MONARCH_PROCESS:
<------><------>/* Reason code 1 means machine check rendezvous*/
<------><------>if (kdump_on_init && (nd->sos->rv_rc != 1)) {
<------><------><------>if (atomic_inc_return(&kdump_in_progress) != 1)
<------><------><------><------>kdump_freeze_monarch = 1;
<------><------>}
<------><------>break;
<------>case DIE_INIT_MONARCH_LEAVE:
<------><------>/* Reason code 1 means machine check rendezvous*/
<------><------>if (kdump_on_init && (nd->sos->rv_rc != 1))
<------><------><------>machine_kdump_on_init();
<------><------>break;
<------>case DIE_MCA_MONARCH_LEAVE:
<------><------>/* *(nd->data) indicate if MCA is recoverable */
<------><------>if (kdump_on_fatal_mca && !(*(nd->data))) {
<------><------><------>if (atomic_inc_return(&kdump_in_progress) == 1)
<------><------><------><------>machine_kdump_on_init();
<------><------><------>/* We got fatal MCA while kdump!? No way!! */
<------><------>}
<------><------>break;
<------>}
<------>return NOTIFY_DONE;
}
 
#ifdef CONFIG_SYSCTL
static struct ctl_table kdump_ctl_table[] = {
<------>{
<------><------>.procname = "kdump_on_init",
<------><------>.data = &kdump_on_init,
<------><------>.maxlen = sizeof(int),
<------><------>.mode = 0644,
<------><------>.proc_handler = proc_dointvec,
<------>},
<------>{
<------><------>.procname = "kdump_on_fatal_mca",
<------><------>.data = &kdump_on_fatal_mca,
<------><------>.maxlen = sizeof(int),
<------><------>.mode = 0644,
<------><------>.proc_handler = proc_dointvec,
<------>},
<------>{ }
};
 
static struct ctl_table sys_table[] = {
<------>{
<------>  .procname = "kernel",
<------>  .mode = 0555,
<------>  .child = kdump_ctl_table,
<------>},
<------>{ }
};
#endif
 
static int
machine_crash_setup(void)
{
<------>/* be notified before default_monarch_init_process */
<------>static struct notifier_block kdump_init_notifier_nb = {
<------><------>.notifier_call = kdump_init_notifier,
<------><------>.priority = 1,
<------>};
<------>int ret;
<------>if((ret = register_die_notifier(&kdump_init_notifier_nb)) != 0)
<------><------>return ret;
#ifdef CONFIG_SYSCTL
<------>register_sysctl_table(sys_table);
#endif
<------>return 0;
}
 
__initcall(machine_crash_setup);