/*
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* SGI NMI support routines
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* Copyright (c) 2009-2013 Silicon Graphics, Inc. All Rights Reserved.
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* Copyright (c) Mike Travis
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*/
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#include <linux/cpu.h>
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#include <linux/delay.h>
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#include <linux/kdb.h>
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#include <linux/kexec.h>
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#include <linux/kgdb.h>
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#include <linux/moduleparam.h>
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#include <linux/nmi.h>
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#include <linux/sched.h>
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#include <linux/sched/debug.h>
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#include <linux/slab.h>
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#include <linux/clocksource.h>
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#include <asm/apic.h>
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#include <asm/current.h>
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#include <asm/kdebug.h>
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#include <asm/local64.h>
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#include <asm/nmi.h>
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#include <asm/traps.h>
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#include <asm/uv/uv.h>
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#include <asm/uv/uv_hub.h>
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#include <asm/uv/uv_mmrs.h>
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/*
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* UV handler for NMI
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*
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* Handle system-wide NMI events generated by the global 'power nmi' command.
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*
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* Basic operation is to field the NMI interrupt on each CPU and wait
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* until all CPU's have arrived into the nmi handler. If some CPU's do not
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* make it into the handler, try and force them in with the IPI(NMI) signal.
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*
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* We also have to lessen UV Hub MMR accesses as much as possible as this
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* disrupts the UV Hub's primary mission of directing NumaLink traffic and
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* can cause system problems to occur.
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*
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* To do this we register our primary NMI notifier on the NMI_UNKNOWN
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* chain. This reduces the number of false NMI calls when the perf
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* tools are running which generate an enormous number of NMIs per
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* second (~4M/s for 1024 CPU threads). Our secondary NMI handler is
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* very short as it only checks that if it has been "pinged" with the
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* IPI(NMI) signal as mentioned above, and does not read the UV Hub's MMR.
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*
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*/
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static struct uv_hub_nmi_s **uv_hub_nmi_list;
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DEFINE_PER_CPU(struct uv_cpu_nmi_s, uv_cpu_nmi);
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/* UV hubless values */
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#define NMI_CONTROL_PORT 0x70
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#define NMI_DUMMY_PORT 0x71
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#define PAD_OWN_GPP_D_0 0x2c
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#define GPI_NMI_STS_GPP_D_0 0x164
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#define GPI_NMI_ENA_GPP_D_0 0x174
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#define STS_GPP_D_0_MASK 0x1
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#define PAD_CFG_DW0_GPP_D_0 0x4c0
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#define GPIROUTNMI (1ul << 17)
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#define PCH_PCR_GPIO_1_BASE 0xfdae0000ul
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#define PCH_PCR_GPIO_ADDRESS(offset) (int *)((u64)(pch_base) | (u64)(offset))
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static u64 *pch_base;
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static unsigned long nmi_mmr;
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static unsigned long nmi_mmr_clear;
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static unsigned long nmi_mmr_pending;
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static atomic_t uv_in_nmi;
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static atomic_t uv_nmi_cpu = ATOMIC_INIT(-1);
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static atomic_t uv_nmi_cpus_in_nmi = ATOMIC_INIT(-1);
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static atomic_t uv_nmi_slave_continue;
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static cpumask_var_t uv_nmi_cpu_mask;
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/* Values for uv_nmi_slave_continue */
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#define SLAVE_CLEAR 0
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#define SLAVE_CONTINUE 1
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#define SLAVE_EXIT 2
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/*
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* Default is all stack dumps go to the console and buffer.
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* Lower level to send to log buffer only.
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*/
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static int uv_nmi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
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module_param_named(dump_loglevel, uv_nmi_loglevel, int, 0644);
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/*
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* The following values show statistics on how perf events are affecting
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* this system.
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*/
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static int param_get_local64(char *buffer, const struct kernel_param *kp)
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{
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return sprintf(buffer, "%lu\n", local64_read((local64_t *)kp->arg));
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}
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static int param_set_local64(const char *val, const struct kernel_param *kp)
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{
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/* Clear on any write */
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local64_set((local64_t *)kp->arg, 0);
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return 0;
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}
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static const struct kernel_param_ops param_ops_local64 = {
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.get = param_get_local64,
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.set = param_set_local64,
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};
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#define param_check_local64(name, p) __param_check(name, p, local64_t)
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static local64_t uv_nmi_count;
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module_param_named(nmi_count, uv_nmi_count, local64, 0644);
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static local64_t uv_nmi_misses;
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module_param_named(nmi_misses, uv_nmi_misses, local64, 0644);
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static local64_t uv_nmi_ping_count;
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module_param_named(ping_count, uv_nmi_ping_count, local64, 0644);
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static local64_t uv_nmi_ping_misses;
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module_param_named(ping_misses, uv_nmi_ping_misses, local64, 0644);
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/*
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* Following values allow tuning for large systems under heavy loading
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*/
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static int uv_nmi_initial_delay = 100;
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module_param_named(initial_delay, uv_nmi_initial_delay, int, 0644);
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static int uv_nmi_slave_delay = 100;
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module_param_named(slave_delay, uv_nmi_slave_delay, int, 0644);
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static int uv_nmi_loop_delay = 100;
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module_param_named(loop_delay, uv_nmi_loop_delay, int, 0644);
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static int uv_nmi_trigger_delay = 10000;
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module_param_named(trigger_delay, uv_nmi_trigger_delay, int, 0644);
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static int uv_nmi_wait_count = 100;
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module_param_named(wait_count, uv_nmi_wait_count, int, 0644);
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static int uv_nmi_retry_count = 500;
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module_param_named(retry_count, uv_nmi_retry_count, int, 0644);
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static bool uv_pch_intr_enable = true;
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static bool uv_pch_intr_now_enabled;
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module_param_named(pch_intr_enable, uv_pch_intr_enable, bool, 0644);
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static bool uv_pch_init_enable = true;
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module_param_named(pch_init_enable, uv_pch_init_enable, bool, 0644);
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static int uv_nmi_debug;
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module_param_named(debug, uv_nmi_debug, int, 0644);
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#define nmi_debug(fmt, ...) \
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do { \
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if (uv_nmi_debug) \
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pr_info(fmt, ##__VA_ARGS__); \
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} while (0)
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/* Valid NMI Actions */
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#define ACTION_LEN 16
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static struct nmi_action {
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char *action;
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char *desc;
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} valid_acts[] = {
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{ "kdump", "do kernel crash dump" },
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{ "dump", "dump process stack for each cpu" },
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{ "ips", "dump Inst Ptr info for each cpu" },
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{ "kdb", "enter KDB (needs kgdboc= assignment)" },
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{ "kgdb", "enter KGDB (needs gdb target remote)" },
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{ "health", "check if CPUs respond to NMI" },
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};
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typedef char action_t[ACTION_LEN];
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static action_t uv_nmi_action = { "dump" };
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static int param_get_action(char *buffer, const struct kernel_param *kp)
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{
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return sprintf(buffer, "%s\n", uv_nmi_action);
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}
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static int param_set_action(const char *val, const struct kernel_param *kp)
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{
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int i;
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int n = ARRAY_SIZE(valid_acts);
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char arg[ACTION_LEN], *p;
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/* (remove possible '\n') */
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strncpy(arg, val, ACTION_LEN - 1);
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arg[ACTION_LEN - 1] = '\0';
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p = strchr(arg, '\n');
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if (p)
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*p = '\0';
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for (i = 0; i < n; i++)
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if (!strcmp(arg, valid_acts[i].action))
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break;
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if (i < n) {
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strcpy(uv_nmi_action, arg);
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pr_info("UV: New NMI action:%s\n", uv_nmi_action);
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return 0;
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}
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pr_err("UV: Invalid NMI action:%s, valid actions are:\n", arg);
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for (i = 0; i < n; i++)
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pr_err("UV: %-8s - %s\n",
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valid_acts[i].action, valid_acts[i].desc);
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return -EINVAL;
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}
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static const struct kernel_param_ops param_ops_action = {
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.get = param_get_action,
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.set = param_set_action,
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};
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#define param_check_action(name, p) __param_check(name, p, action_t)
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module_param_named(action, uv_nmi_action, action, 0644);
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static inline bool uv_nmi_action_is(const char *action)
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{
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return (strncmp(uv_nmi_action, action, strlen(action)) == 0);
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}
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/* Setup which NMI support is present in system */
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static void uv_nmi_setup_mmrs(void)
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{
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if (uv_read_local_mmr(UVH_NMI_MMRX_SUPPORTED)) {
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uv_write_local_mmr(UVH_NMI_MMRX_REQ,
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1UL << UVH_NMI_MMRX_REQ_SHIFT);
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nmi_mmr = UVH_NMI_MMRX;
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nmi_mmr_clear = UVH_NMI_MMRX_CLEAR;
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nmi_mmr_pending = 1UL << UVH_NMI_MMRX_SHIFT;
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pr_info("UV: SMI NMI support: %s\n", UVH_NMI_MMRX_TYPE);
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} else {
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nmi_mmr = UVH_NMI_MMR;
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nmi_mmr_clear = UVH_NMI_MMR_CLEAR;
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nmi_mmr_pending = 1UL << UVH_NMI_MMR_SHIFT;
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pr_info("UV: SMI NMI support: %s\n", UVH_NMI_MMR_TYPE);
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}
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}
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/* Read NMI MMR and check if NMI flag was set by BMC. */
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static inline int uv_nmi_test_mmr(struct uv_hub_nmi_s *hub_nmi)
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{
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hub_nmi->nmi_value = uv_read_local_mmr(nmi_mmr);
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atomic_inc(&hub_nmi->read_mmr_count);
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return !!(hub_nmi->nmi_value & nmi_mmr_pending);
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}
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static inline void uv_local_mmr_clear_nmi(void)
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{
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uv_write_local_mmr(nmi_mmr_clear, nmi_mmr_pending);
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}
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/*
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* UV hubless NMI handler functions
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*/
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static inline void uv_reassert_nmi(void)
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{
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/* (from arch/x86/include/asm/mach_traps.h) */
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outb(0x8f, NMI_CONTROL_PORT);
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inb(NMI_DUMMY_PORT); /* dummy read */
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outb(0x0f, NMI_CONTROL_PORT);
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inb(NMI_DUMMY_PORT); /* dummy read */
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}
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static void uv_init_hubless_pch_io(int offset, int mask, int data)
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{
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int *addr = PCH_PCR_GPIO_ADDRESS(offset);
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int readd = readl(addr);
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if (mask) { /* OR in new data */
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int writed = (readd & ~mask) | data;
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nmi_debug("UV:PCH: %p = %x & %x | %x (%x)\n",
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addr, readd, ~mask, data, writed);
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writel(writed, addr);
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} else if (readd & data) { /* clear status bit */
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nmi_debug("UV:PCH: %p = %x\n", addr, data);
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writel(data, addr);
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}
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(void)readl(addr); /* flush write data */
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}
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static void uv_nmi_setup_hubless_intr(void)
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{
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uv_pch_intr_now_enabled = uv_pch_intr_enable;
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uv_init_hubless_pch_io(
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PAD_CFG_DW0_GPP_D_0, GPIROUTNMI,
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uv_pch_intr_now_enabled ? GPIROUTNMI : 0);
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nmi_debug("UV:NMI: GPP_D_0 interrupt %s\n",
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uv_pch_intr_now_enabled ? "enabled" : "disabled");
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}
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static struct init_nmi {
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unsigned int offset;
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unsigned int mask;
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unsigned int data;
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} init_nmi[] = {
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{ /* HOSTSW_OWN_GPP_D_0 */
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.offset = 0x84,
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.mask = 0x1,
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.data = 0x0, /* ACPI Mode */
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},
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/* Clear status: */
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{ /* GPI_INT_STS_GPP_D_0 */
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.offset = 0x104,
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.mask = 0x0,
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.data = 0x1, /* Clear Status */
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},
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{ /* GPI_GPE_STS_GPP_D_0 */
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.offset = 0x124,
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.mask = 0x0,
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.data = 0x1, /* Clear Status */
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},
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{ /* GPI_SMI_STS_GPP_D_0 */
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.offset = 0x144,
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.mask = 0x0,
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.data = 0x1, /* Clear Status */
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},
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{ /* GPI_NMI_STS_GPP_D_0 */
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.offset = 0x164,
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.mask = 0x0,
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.data = 0x1, /* Clear Status */
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},
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/* Disable interrupts: */
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{ /* GPI_INT_EN_GPP_D_0 */
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.offset = 0x114,
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.mask = 0x1,
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.data = 0x0, /* Disable interrupt generation */
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},
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{ /* GPI_GPE_EN_GPP_D_0 */
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.offset = 0x134,
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.mask = 0x1,
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.data = 0x0, /* Disable interrupt generation */
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},
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{ /* GPI_SMI_EN_GPP_D_0 */
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.offset = 0x154,
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.mask = 0x1,
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.data = 0x0, /* Disable interrupt generation */
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},
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{ /* GPI_NMI_EN_GPP_D_0 */
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.offset = 0x174,
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.mask = 0x1,
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.data = 0x0, /* Disable interrupt generation */
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},
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/* Setup GPP_D_0 Pad Config: */
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{ /* PAD_CFG_DW0_GPP_D_0 */
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.offset = 0x4c0,
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.mask = 0xffffffff,
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.data = 0x82020100,
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/*
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* 31:30 Pad Reset Config (PADRSTCFG): = 2h # PLTRST# (default)
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*
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* 29 RX Pad State Select (RXPADSTSEL): = 0 # Raw RX pad state directly
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* from RX buffer (default)
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*
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* 28 RX Raw Override to '1' (RXRAW1): = 0 # No Override
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*
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* 26:25 RX Level/Edge Configuration (RXEVCFG):
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* = 0h # Level
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* = 1h # Edge
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*
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* 23 RX Invert (RXINV): = 0 # No Inversion (signal active high)
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*
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* 20 GPIO Input Route IOxAPIC (GPIROUTIOXAPIC):
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* = 0 # Routing does not cause peripheral IRQ...
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* # (we want an NMI not an IRQ)
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*
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* 19 GPIO Input Route SCI (GPIROUTSCI): = 0 # Routing does not cause SCI.
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* 18 GPIO Input Route SMI (GPIROUTSMI): = 0 # Routing does not cause SMI.
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* 17 GPIO Input Route NMI (GPIROUTNMI): = 1 # Routing can cause NMI.
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*
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* 11:10 Pad Mode (PMODE1/0): = 0h = GPIO control the Pad.
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* 9 GPIO RX Disable (GPIORXDIS):
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* = 0 # Enable the input buffer (active low enable)
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*
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* 8 GPIO TX Disable (GPIOTXDIS):
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* = 1 # Disable the output buffer; i.e. Hi-Z
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*
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* 1 GPIO RX State (GPIORXSTATE): This is the current internal RX pad state..
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* 0 GPIO TX State (GPIOTXSTATE):
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* = 0 # (Leave at default)
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*/
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},
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/* Pad Config DW1 */
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{ /* PAD_CFG_DW1_GPP_D_0 */
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.offset = 0x4c4,
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.mask = 0x3c00,
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.data = 0, /* Termination = none (default) */
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},
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};
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static void uv_init_hubless_pch_d0(void)
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{
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int i, read;
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read = *PCH_PCR_GPIO_ADDRESS(PAD_OWN_GPP_D_0);
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if (read != 0) {
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pr_info("UV: Hubless NMI already configured\n");
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return;
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}
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nmi_debug("UV: Initializing UV Hubless NMI on PCH\n");
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for (i = 0; i < ARRAY_SIZE(init_nmi); i++) {
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uv_init_hubless_pch_io(init_nmi[i].offset,
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init_nmi[i].mask,
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init_nmi[i].data);
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}
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}
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static int uv_nmi_test_hubless(struct uv_hub_nmi_s *hub_nmi)
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{
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int *pstat = PCH_PCR_GPIO_ADDRESS(GPI_NMI_STS_GPP_D_0);
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int status = *pstat;
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hub_nmi->nmi_value = status;
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atomic_inc(&hub_nmi->read_mmr_count);
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if (!(status & STS_GPP_D_0_MASK)) /* Not a UV external NMI */
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return 0;
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*pstat = STS_GPP_D_0_MASK; /* Is a UV NMI: clear GPP_D_0 status */
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(void)*pstat; /* Flush write */
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return 1;
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}
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static int uv_test_nmi(struct uv_hub_nmi_s *hub_nmi)
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{
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if (hub_nmi->hub_present)
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return uv_nmi_test_mmr(hub_nmi);
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if (hub_nmi->pch_owner) /* Only PCH owner can check status */
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return uv_nmi_test_hubless(hub_nmi);
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return -1;
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}
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/*
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* If first CPU in on this hub, set hub_nmi "in_nmi" and "owner" values and
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* return true. If first CPU in on the system, set global "in_nmi" flag.
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*/
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static int uv_set_in_nmi(int cpu, struct uv_hub_nmi_s *hub_nmi)
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{
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int first = atomic_add_unless(&hub_nmi->in_nmi, 1, 1);
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if (first) {
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atomic_set(&hub_nmi->cpu_owner, cpu);
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if (atomic_add_unless(&uv_in_nmi, 1, 1))
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atomic_set(&uv_nmi_cpu, cpu);
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atomic_inc(&hub_nmi->nmi_count);
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}
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return first;
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}
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/* Check if this is a system NMI event */
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static int uv_check_nmi(struct uv_hub_nmi_s *hub_nmi)
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{
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int cpu = smp_processor_id();
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int nmi = 0;
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int nmi_detected = 0;
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local64_inc(&uv_nmi_count);
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this_cpu_inc(uv_cpu_nmi.queries);
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do {
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nmi = atomic_read(&hub_nmi->in_nmi);
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if (nmi)
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break;
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if (raw_spin_trylock(&hub_nmi->nmi_lock)) {
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nmi_detected = uv_test_nmi(hub_nmi);
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/* Check flag for UV external NMI */
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if (nmi_detected > 0) {
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uv_set_in_nmi(cpu, hub_nmi);
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nmi = 1;
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break;
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}
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/* A non-PCH node in a hubless system waits for NMI */
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else if (nmi_detected < 0)
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goto slave_wait;
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/* MMR/PCH NMI flag is clear */
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raw_spin_unlock(&hub_nmi->nmi_lock);
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} else {
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/* Wait a moment for the HUB NMI locker to set flag */
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slave_wait: cpu_relax();
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udelay(uv_nmi_slave_delay);
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/* Re-check hub in_nmi flag */
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nmi = atomic_read(&hub_nmi->in_nmi);
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if (nmi)
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break;
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}
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/*
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* Check if this BMC missed setting the MMR NMI flag (or)
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* UV hubless system where only PCH owner can check flag
|
*/
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if (!nmi) {
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nmi = atomic_read(&uv_in_nmi);
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if (nmi)
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uv_set_in_nmi(cpu, hub_nmi);
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}
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/* If we're holding the hub lock, release it now */
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if (nmi_detected < 0)
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raw_spin_unlock(&hub_nmi->nmi_lock);
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} while (0);
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if (!nmi)
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local64_inc(&uv_nmi_misses);
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return nmi;
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}
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/* Need to reset the NMI MMR register, but only once per hub. */
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static inline void uv_clear_nmi(int cpu)
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{
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struct uv_hub_nmi_s *hub_nmi = uv_hub_nmi;
|
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if (cpu == atomic_read(&hub_nmi->cpu_owner)) {
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atomic_set(&hub_nmi->cpu_owner, -1);
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atomic_set(&hub_nmi->in_nmi, 0);
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if (hub_nmi->hub_present)
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uv_local_mmr_clear_nmi();
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else
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uv_reassert_nmi();
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raw_spin_unlock(&hub_nmi->nmi_lock);
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}
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}
|
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/* Ping non-responding CPU's attemping to force them into the NMI handler */
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static void uv_nmi_nr_cpus_ping(void)
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{
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int cpu;
|
|
for_each_cpu(cpu, uv_nmi_cpu_mask)
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uv_cpu_nmi_per(cpu).pinging = 1;
|
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apic->send_IPI_mask(uv_nmi_cpu_mask, APIC_DM_NMI);
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}
|
|
/* Clean up flags for CPU's that ignored both NMI and ping */
|
static void uv_nmi_cleanup_mask(void)
|
{
|
int cpu;
|
|
for_each_cpu(cpu, uv_nmi_cpu_mask) {
|
uv_cpu_nmi_per(cpu).pinging = 0;
|
uv_cpu_nmi_per(cpu).state = UV_NMI_STATE_OUT;
|
cpumask_clear_cpu(cpu, uv_nmi_cpu_mask);
|
}
|
}
|
|
/* Loop waiting as CPU's enter NMI handler */
|
static int uv_nmi_wait_cpus(int first)
|
{
|
int i, j, k, n = num_online_cpus();
|
int last_k = 0, waiting = 0;
|
int cpu = smp_processor_id();
|
|
if (first) {
|
cpumask_copy(uv_nmi_cpu_mask, cpu_online_mask);
|
k = 0;
|
} else {
|
k = n - cpumask_weight(uv_nmi_cpu_mask);
|
}
|
|
/* PCH NMI causes only one CPU to respond */
|
if (first && uv_pch_intr_now_enabled) {
|
cpumask_clear_cpu(cpu, uv_nmi_cpu_mask);
|
return n - k - 1;
|
}
|
|
udelay(uv_nmi_initial_delay);
|
for (i = 0; i < uv_nmi_retry_count; i++) {
|
int loop_delay = uv_nmi_loop_delay;
|
|
for_each_cpu(j, uv_nmi_cpu_mask) {
|
if (uv_cpu_nmi_per(j).state) {
|
cpumask_clear_cpu(j, uv_nmi_cpu_mask);
|
if (++k >= n)
|
break;
|
}
|
}
|
if (k >= n) { /* all in? */
|
k = n;
|
break;
|
}
|
if (last_k != k) { /* abort if no new CPU's coming in */
|
last_k = k;
|
waiting = 0;
|
} else if (++waiting > uv_nmi_wait_count)
|
break;
|
|
/* Extend delay if waiting only for CPU 0: */
|
if (waiting && (n - k) == 1 &&
|
cpumask_test_cpu(0, uv_nmi_cpu_mask))
|
loop_delay *= 100;
|
|
udelay(loop_delay);
|
}
|
atomic_set(&uv_nmi_cpus_in_nmi, k);
|
return n - k;
|
}
|
|
/* Wait until all slave CPU's have entered UV NMI handler */
|
static void uv_nmi_wait(int master)
|
{
|
/* Indicate this CPU is in: */
|
this_cpu_write(uv_cpu_nmi.state, UV_NMI_STATE_IN);
|
|
/* If not the first CPU in (the master), then we are a slave CPU */
|
if (!master)
|
return;
|
|
do {
|
/* Wait for all other CPU's to gather here */
|
if (!uv_nmi_wait_cpus(1))
|
break;
|
|
/* If not all made it in, send IPI NMI to them */
|
pr_alert("UV: Sending NMI IPI to %d CPUs: %*pbl\n",
|
cpumask_weight(uv_nmi_cpu_mask),
|
cpumask_pr_args(uv_nmi_cpu_mask));
|
|
uv_nmi_nr_cpus_ping();
|
|
/* If all CPU's are in, then done */
|
if (!uv_nmi_wait_cpus(0))
|
break;
|
|
pr_alert("UV: %d CPUs not in NMI loop: %*pbl\n",
|
cpumask_weight(uv_nmi_cpu_mask),
|
cpumask_pr_args(uv_nmi_cpu_mask));
|
} while (0);
|
|
pr_alert("UV: %d of %d CPUs in NMI\n",
|
atomic_read(&uv_nmi_cpus_in_nmi), num_online_cpus());
|
}
|
|
/* Dump Instruction Pointer header */
|
static void uv_nmi_dump_cpu_ip_hdr(void)
|
{
|
pr_info("\nUV: %4s %6s %-32s %s (Note: PID 0 not listed)\n",
|
"CPU", "PID", "COMMAND", "IP");
|
}
|
|
/* Dump Instruction Pointer info */
|
static void uv_nmi_dump_cpu_ip(int cpu, struct pt_regs *regs)
|
{
|
pr_info("UV: %4d %6d %-32.32s %pS",
|
cpu, current->pid, current->comm, (void *)regs->ip);
|
}
|
|
/*
|
* Dump this CPU's state. If action was set to "kdump" and the crash_kexec
|
* failed, then we provide "dump" as an alternate action. Action "dump" now
|
* also includes the show "ips" (instruction pointers) action whereas the
|
* action "ips" only displays instruction pointers for the non-idle CPU's.
|
* This is an abbreviated form of the "ps" command.
|
*/
|
static void uv_nmi_dump_state_cpu(int cpu, struct pt_regs *regs)
|
{
|
const char *dots = " ................................. ";
|
|
if (cpu == 0)
|
uv_nmi_dump_cpu_ip_hdr();
|
|
if (current->pid != 0 || !uv_nmi_action_is("ips"))
|
uv_nmi_dump_cpu_ip(cpu, regs);
|
|
if (uv_nmi_action_is("dump")) {
|
pr_info("UV:%sNMI process trace for CPU %d\n", dots, cpu);
|
show_regs(regs);
|
}
|
|
this_cpu_write(uv_cpu_nmi.state, UV_NMI_STATE_DUMP_DONE);
|
}
|
|
/* Trigger a slave CPU to dump it's state */
|
static void uv_nmi_trigger_dump(int cpu)
|
{
|
int retry = uv_nmi_trigger_delay;
|
|
if (uv_cpu_nmi_per(cpu).state != UV_NMI_STATE_IN)
|
return;
|
|
uv_cpu_nmi_per(cpu).state = UV_NMI_STATE_DUMP;
|
do {
|
cpu_relax();
|
udelay(10);
|
if (uv_cpu_nmi_per(cpu).state
|
!= UV_NMI_STATE_DUMP)
|
return;
|
} while (--retry > 0);
|
|
pr_crit("UV: CPU %d stuck in process dump function\n", cpu);
|
uv_cpu_nmi_per(cpu).state = UV_NMI_STATE_DUMP_DONE;
|
}
|
|
/* Wait until all CPU's ready to exit */
|
static void uv_nmi_sync_exit(int master)
|
{
|
atomic_dec(&uv_nmi_cpus_in_nmi);
|
if (master) {
|
while (atomic_read(&uv_nmi_cpus_in_nmi) > 0)
|
cpu_relax();
|
atomic_set(&uv_nmi_slave_continue, SLAVE_CLEAR);
|
} else {
|
while (atomic_read(&uv_nmi_slave_continue))
|
cpu_relax();
|
}
|
}
|
|
/* Current "health" check is to check which CPU's are responsive */
|
static void uv_nmi_action_health(int cpu, struct pt_regs *regs, int master)
|
{
|
if (master) {
|
int in = atomic_read(&uv_nmi_cpus_in_nmi);
|
int out = num_online_cpus() - in;
|
|
pr_alert("UV: NMI CPU health check (non-responding:%d)\n", out);
|
atomic_set(&uv_nmi_slave_continue, SLAVE_EXIT);
|
} else {
|
while (!atomic_read(&uv_nmi_slave_continue))
|
cpu_relax();
|
}
|
uv_nmi_sync_exit(master);
|
}
|
|
/* Walk through CPU list and dump state of each */
|
static void uv_nmi_dump_state(int cpu, struct pt_regs *regs, int master)
|
{
|
if (master) {
|
int tcpu;
|
int ignored = 0;
|
int saved_console_loglevel = console_loglevel;
|
|
pr_alert("UV: tracing %s for %d CPUs from CPU %d\n",
|
uv_nmi_action_is("ips") ? "IPs" : "processes",
|
atomic_read(&uv_nmi_cpus_in_nmi), cpu);
|
|
console_loglevel = uv_nmi_loglevel;
|
atomic_set(&uv_nmi_slave_continue, SLAVE_EXIT);
|
for_each_online_cpu(tcpu) {
|
if (cpumask_test_cpu(tcpu, uv_nmi_cpu_mask))
|
ignored++;
|
else if (tcpu == cpu)
|
uv_nmi_dump_state_cpu(tcpu, regs);
|
else
|
uv_nmi_trigger_dump(tcpu);
|
}
|
if (ignored)
|
pr_alert("UV: %d CPUs ignored NMI\n", ignored);
|
|
console_loglevel = saved_console_loglevel;
|
pr_alert("UV: process trace complete\n");
|
} else {
|
while (!atomic_read(&uv_nmi_slave_continue))
|
cpu_relax();
|
while (this_cpu_read(uv_cpu_nmi.state) != UV_NMI_STATE_DUMP)
|
cpu_relax();
|
uv_nmi_dump_state_cpu(cpu, regs);
|
}
|
uv_nmi_sync_exit(master);
|
}
|
|
static void uv_nmi_touch_watchdogs(void)
|
{
|
touch_softlockup_watchdog_sync();
|
clocksource_touch_watchdog();
|
rcu_cpu_stall_reset();
|
touch_nmi_watchdog();
|
}
|
|
static atomic_t uv_nmi_kexec_failed;
|
|
#if defined(CONFIG_KEXEC_CORE)
|
static void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
|
{
|
/* Call crash to dump system state */
|
if (master) {
|
pr_emerg("UV: NMI executing crash_kexec on CPU%d\n", cpu);
|
crash_kexec(regs);
|
|
pr_emerg("UV: crash_kexec unexpectedly returned, ");
|
atomic_set(&uv_nmi_kexec_failed, 1);
|
if (!kexec_crash_image) {
|
pr_cont("crash kernel not loaded\n");
|
return;
|
}
|
pr_cont("kexec busy, stalling cpus while waiting\n");
|
}
|
|
/* If crash exec fails the slaves should return, otherwise stall */
|
while (atomic_read(&uv_nmi_kexec_failed) == 0)
|
mdelay(10);
|
}
|
|
#else /* !CONFIG_KEXEC_CORE */
|
static inline void uv_nmi_kdump(int cpu, int master, struct pt_regs *regs)
|
{
|
if (master)
|
pr_err("UV: NMI kdump: KEXEC not supported in this kernel\n");
|
atomic_set(&uv_nmi_kexec_failed, 1);
|
}
|
#endif /* !CONFIG_KEXEC_CORE */
|
|
#ifdef CONFIG_KGDB
|
#ifdef CONFIG_KGDB_KDB
|
static inline int uv_nmi_kdb_reason(void)
|
{
|
return KDB_REASON_SYSTEM_NMI;
|
}
|
#else /* !CONFIG_KGDB_KDB */
|
static inline int uv_nmi_kdb_reason(void)
|
{
|
/* Ensure user is expecting to attach gdb remote */
|
if (uv_nmi_action_is("kgdb"))
|
return 0;
|
|
pr_err("UV: NMI error: KDB is not enabled in this kernel\n");
|
return -1;
|
}
|
#endif /* CONFIG_KGDB_KDB */
|
|
/*
|
* Call KGDB/KDB from NMI handler
|
*
|
* Note that if both KGDB and KDB are configured, then the action of 'kgdb' or
|
* 'kdb' has no affect on which is used. See the KGDB documention for further
|
* information.
|
*/
|
static void uv_call_kgdb_kdb(int cpu, struct pt_regs *regs, int master)
|
{
|
if (master) {
|
int reason = uv_nmi_kdb_reason();
|
int ret;
|
|
if (reason < 0)
|
return;
|
|
/* Call KGDB NMI handler as MASTER */
|
ret = kgdb_nmicallin(cpu, X86_TRAP_NMI, regs, reason,
|
&uv_nmi_slave_continue);
|
if (ret) {
|
pr_alert("KGDB returned error, is kgdboc set?\n");
|
atomic_set(&uv_nmi_slave_continue, SLAVE_EXIT);
|
}
|
} else {
|
/* Wait for KGDB signal that it's ready for slaves to enter */
|
int sig;
|
|
do {
|
cpu_relax();
|
sig = atomic_read(&uv_nmi_slave_continue);
|
} while (!sig);
|
|
/* Call KGDB as slave */
|
if (sig == SLAVE_CONTINUE)
|
kgdb_nmicallback(cpu, regs);
|
}
|
uv_nmi_sync_exit(master);
|
}
|
|
#else /* !CONFIG_KGDB */
|
static inline void uv_call_kgdb_kdb(int cpu, struct pt_regs *regs, int master)
|
{
|
pr_err("UV: NMI error: KGDB is not enabled in this kernel\n");
|
}
|
#endif /* !CONFIG_KGDB */
|
|
/*
|
* UV NMI handler
|
*/
|
static int uv_handle_nmi(unsigned int reason, struct pt_regs *regs)
|
{
|
struct uv_hub_nmi_s *hub_nmi = uv_hub_nmi;
|
int cpu = smp_processor_id();
|
int master = 0;
|
unsigned long flags;
|
|
local_irq_save(flags);
|
|
/* If not a UV System NMI, ignore */
|
if (!this_cpu_read(uv_cpu_nmi.pinging) && !uv_check_nmi(hub_nmi)) {
|
local_irq_restore(flags);
|
return NMI_DONE;
|
}
|
|
/* Indicate we are the first CPU into the NMI handler */
|
master = (atomic_read(&uv_nmi_cpu) == cpu);
|
|
/* If NMI action is "kdump", then attempt to do it */
|
if (uv_nmi_action_is("kdump")) {
|
uv_nmi_kdump(cpu, master, regs);
|
|
/* Unexpected return, revert action to "dump" */
|
if (master)
|
strncpy(uv_nmi_action, "dump", strlen(uv_nmi_action));
|
}
|
|
/* Pause as all CPU's enter the NMI handler */
|
uv_nmi_wait(master);
|
|
/* Process actions other than "kdump": */
|
if (uv_nmi_action_is("health")) {
|
uv_nmi_action_health(cpu, regs, master);
|
} else if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) {
|
uv_nmi_dump_state(cpu, regs, master);
|
} else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb")) {
|
uv_call_kgdb_kdb(cpu, regs, master);
|
} else {
|
if (master)
|
pr_alert("UV: unknown NMI action: %s\n", uv_nmi_action);
|
uv_nmi_sync_exit(master);
|
}
|
|
/* Clear per_cpu "in_nmi" flag */
|
this_cpu_write(uv_cpu_nmi.state, UV_NMI_STATE_OUT);
|
|
/* Clear MMR NMI flag on each hub */
|
uv_clear_nmi(cpu);
|
|
/* Clear global flags */
|
if (master) {
|
if (cpumask_weight(uv_nmi_cpu_mask))
|
uv_nmi_cleanup_mask();
|
atomic_set(&uv_nmi_cpus_in_nmi, -1);
|
atomic_set(&uv_nmi_cpu, -1);
|
atomic_set(&uv_in_nmi, 0);
|
atomic_set(&uv_nmi_kexec_failed, 0);
|
atomic_set(&uv_nmi_slave_continue, SLAVE_CLEAR);
|
}
|
|
uv_nmi_touch_watchdogs();
|
local_irq_restore(flags);
|
|
return NMI_HANDLED;
|
}
|
|
/*
|
* NMI handler for pulling in CPU's when perf events are grabbing our NMI
|
*/
|
static int uv_handle_nmi_ping(unsigned int reason, struct pt_regs *regs)
|
{
|
int ret;
|
|
this_cpu_inc(uv_cpu_nmi.queries);
|
if (!this_cpu_read(uv_cpu_nmi.pinging)) {
|
local64_inc(&uv_nmi_ping_misses);
|
return NMI_DONE;
|
}
|
|
this_cpu_inc(uv_cpu_nmi.pings);
|
local64_inc(&uv_nmi_ping_count);
|
ret = uv_handle_nmi(reason, regs);
|
this_cpu_write(uv_cpu_nmi.pinging, 0);
|
return ret;
|
}
|
|
static void uv_register_nmi_notifier(void)
|
{
|
if (register_nmi_handler(NMI_UNKNOWN, uv_handle_nmi, 0, "uv"))
|
pr_warn("UV: NMI handler failed to register\n");
|
|
if (register_nmi_handler(NMI_LOCAL, uv_handle_nmi_ping, 0, "uvping"))
|
pr_warn("UV: PING NMI handler failed to register\n");
|
}
|
|
void uv_nmi_init(void)
|
{
|
unsigned int value;
|
|
/*
|
* Unmask NMI on all CPU's
|
*/
|
value = apic_read(APIC_LVT1) | APIC_DM_NMI;
|
value &= ~APIC_LVT_MASKED;
|
apic_write(APIC_LVT1, value);
|
}
|
|
/* Setup HUB NMI info */
|
static void __init uv_nmi_setup_common(bool hubbed)
|
{
|
int size = sizeof(void *) * (1 << NODES_SHIFT);
|
int cpu;
|
|
uv_hub_nmi_list = kzalloc(size, GFP_KERNEL);
|
nmi_debug("UV: NMI hub list @ 0x%p (%d)\n", uv_hub_nmi_list, size);
|
BUG_ON(!uv_hub_nmi_list);
|
size = sizeof(struct uv_hub_nmi_s);
|
for_each_present_cpu(cpu) {
|
int nid = cpu_to_node(cpu);
|
if (uv_hub_nmi_list[nid] == NULL) {
|
uv_hub_nmi_list[nid] = kzalloc_node(size,
|
GFP_KERNEL, nid);
|
BUG_ON(!uv_hub_nmi_list[nid]);
|
raw_spin_lock_init(&(uv_hub_nmi_list[nid]->nmi_lock));
|
atomic_set(&uv_hub_nmi_list[nid]->cpu_owner, -1);
|
uv_hub_nmi_list[nid]->hub_present = hubbed;
|
uv_hub_nmi_list[nid]->pch_owner = (nid == 0);
|
}
|
uv_hub_nmi_per(cpu) = uv_hub_nmi_list[nid];
|
}
|
BUG_ON(!alloc_cpumask_var(&uv_nmi_cpu_mask, GFP_KERNEL));
|
}
|
|
/* Setup for UV Hub systems */
|
void __init uv_nmi_setup(void)
|
{
|
uv_nmi_setup_mmrs();
|
uv_nmi_setup_common(true);
|
uv_register_nmi_notifier();
|
pr_info("UV: Hub NMI enabled\n");
|
}
|
|
/* Setup for UV Hubless systems */
|
void __init uv_nmi_setup_hubless(void)
|
{
|
uv_nmi_setup_common(false);
|
pch_base = xlate_dev_mem_ptr(PCH_PCR_GPIO_1_BASE);
|
nmi_debug("UV: PCH base:%p from 0x%lx, GPP_D_0\n",
|
pch_base, PCH_PCR_GPIO_1_BASE);
|
if (uv_pch_init_enable)
|
uv_init_hubless_pch_d0();
|
uv_init_hubless_pch_io(GPI_NMI_ENA_GPP_D_0,
|
STS_GPP_D_0_MASK, STS_GPP_D_0_MASK);
|
uv_nmi_setup_hubless_intr();
|
/* Ensure NMI enabled in Processor Interface Reg: */
|
uv_reassert_nmi();
|
uv_register_nmi_notifier();
|
pr_info("UV: Hubless NMI enabled\n");
|
}
|
