OpenCloudOS-Kernel/arch/arm/include/asm/smp.h

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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/smp.h
*
* Copyright (C) 2004-2005 ARM Ltd.
*/
#ifndef __ASM_ARM_SMP_H
#define __ASM_ARM_SMP_H
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/thread_info.h>
#ifndef CONFIG_SMP
# error "<asm/smp.h> included in non-SMP build"
#endif
#define raw_smp_processor_id() (current_thread_info()->cpu)
struct seq_file;
/*
* generate IPI list text
*/
extern void show_ipi_list(struct seq_file *, int);
/*
* Called from assembly code, this handles an IPI.
*/
asmlinkage void do_IPI(int ipinr, struct pt_regs *regs);
/*
* Called from C code, this handles an IPI.
*/
void handle_IPI(int ipinr, struct pt_regs *regs);
/*
* Setup the set of possible CPUs (via set_cpu_possible)
*/
extern void smp_init_cpus(void);
/*
* Register IPI interrupts with the arch SMP code
*/
extern void set_smp_ipi_range(int ipi_base, int nr_ipi);
/*
* Called from platform specific assembly code, this is the
* secondary CPU entry point.
*/
asmlinkage void secondary_start_kernel(void);
/*
* Initial data for bringing up a secondary CPU.
*/
struct secondary_data {
union {
ARM: 8708/1: NOMMU: Rework MPU to be mostly done in C Currently, there are several issues with how MPU is setup: 1. We won't boot if MPU is missing 2. We won't boot if use XIP 3. Further extension of MPU setup requires asm skills The 1st point can be relaxed, so we can continue with boot CPU even if MPU is missed and fail boot for secondaries only. To address the 2nd point we could create region covering CONFIG_XIP_PHYS_ADDR - _end and that might work for the first stage of MPU enable, but due to MPU's alignment requirement we could cover too much, IOW we need more flexibility in how we're partitioning memory regions... and it'd be hardly possible to archive because of the 3rd point. This patch is trying to address 1st and 3rd issues and paves the path for 2nd and further improvements. The most visible change introduced with this patch is that we start using mpu_rgn_info array (as it was supposed?), so change in MPU setup done by boot CPU is recorded there and feed to secondaries. It allows us to keep minimal region setup for boot CPU and do the rest in C. Since we start programming MPU regions in C evaluation of MPU constrains (number of regions supported and minimal region order) can be done once, which in turn open possibility to free-up "probe" region early. Tested-by: Szemző András <sza@esh.hu> Tested-by: Alexandre TORGUE <alexandre.torgue@st.com> Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-10-16 19:54:05 +08:00
struct mpu_rgn_info *mpu_rgn_info;
u64 pgdir;
};
unsigned long swapper_pg_dir;
void *stack;
};
extern struct secondary_data secondary_data;
extern void secondary_startup(void);
extern void secondary_startup_arm(void);
extern int __cpu_disable(void);
extern void __cpu_die(unsigned int cpu);
extern void arch_send_call_function_single_ipi(int cpu);
extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask);
extern int register_ipi_completion(struct completion *completion, int cpu);
struct smp_operations {
#ifdef CONFIG_SMP
/*
* Setup the set of possible CPUs (via set_cpu_possible)
*/
void (*smp_init_cpus)(void);
/*
* Initialize cpu_possible map, and enable coherency
*/
void (*smp_prepare_cpus)(unsigned int max_cpus);
/*
* Perform platform specific initialisation of the specified CPU.
*/
void (*smp_secondary_init)(unsigned int cpu);
/*
* Boot a secondary CPU, and assign it the specified idle task.
* This also gives us the initial stack to use for this CPU.
*/
int (*smp_boot_secondary)(unsigned int cpu, struct task_struct *idle);
#ifdef CONFIG_HOTPLUG_CPU
int (*cpu_kill)(unsigned int cpu);
void (*cpu_die)(unsigned int cpu);
ARM: 8392/3: smp: Only expose /sys/.../cpuX/online if hotpluggable Writes to /sys/.../cpuX/online fail if we determine the platform doesn't support hotplug for that CPU. Furthermore, if the cpu_die op isn't specified the system hangs when we try to offline a CPU and it comes right back online unexpectedly. Let's figure this stuff out before we make the sysfs nodes so that the online file doesn't even exist if it isn't (at least sometimes) possible to hotplug the CPU. Add a new 'cpu_can_disable' op and repoint all 'cpu_disable' implementations at it because all implementers use the op to indicate if a CPU can be hotplugged or not in a static fashion. With PSCI we may need to add a 'cpu_disable' op so that the secure OS can be migrated off the CPU we're trying to hotplug. In this case, the 'cpu_can_disable' op will indicate that all CPUs are hotpluggable by returning true, but the 'cpu_disable' op will make a PSCI migration call and occasionally fail, denying the hotplug of a CPU. This shouldn't be any worse than x86 where we may indicate that all CPUs are hotpluggable but occasionally we can't offline a CPU due to check_irq_vectors_for_cpu_disable() failing to find a CPU to move vectors to. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Nicolas Pitre <nico@linaro.org> Cc: Dave Martin <Dave.Martin@arm.com> Acked-by: Simon Horman <horms@verge.net.au> [shmobile portion] Tested-by: Simon Horman <horms@verge.net.au> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: <linux-sh@vger.kernel.org> Tested-by: Tyler Baker <tyler.baker@linaro.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-07-29 07:34:48 +08:00
bool (*cpu_can_disable)(unsigned int cpu);
int (*cpu_disable)(unsigned int cpu);
#endif
#endif
};
struct of_cpu_method {
const char *method;
const struct smp_operations *ops;
};
#define CPU_METHOD_OF_DECLARE(name, _method, _ops) \
static const struct of_cpu_method __cpu_method_of_table_##name \
__used __section("__cpu_method_of_table") \
= { .method = _method, .ops = _ops }
/*
* set platform specific SMP operations
*/
extern void smp_set_ops(const struct smp_operations *);
#endif /* ifndef __ASM_ARM_SMP_H */