linux_dsm_epyc7002/arch/arm/kernel/psci_smp.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2012 ARM Limited
*
* Author: Will Deacon <will.deacon@arm.com>
*/
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/of.h>
#include <linux/delay.h>
#include <linux/psci.h>
#include <uapi/linux/psci.h>
#include <asm/psci.h>
#include <asm/smp_plat.h>
/*
* psci_smp assumes that the following is true about PSCI:
*
* cpu_suspend Suspend the execution on a CPU
* @state we don't currently describe affinity levels, so just pass 0.
* @entry_point the first instruction to be executed on return
* returns 0 success, < 0 on failure
*
* cpu_off Power down a CPU
* @state we don't currently describe affinity levels, so just pass 0.
* no return on successful call
*
* cpu_on Power up a CPU
* @cpuid cpuid of target CPU, as from MPIDR
* @entry_point the first instruction to be executed on return
* returns 0 success, < 0 on failure
*
* migrate Migrate the context to a different CPU
* @cpuid cpuid of target CPU, as from MPIDR
* returns 0 success, < 0 on failure
*
*/
extern void secondary_startup(void);
arm: delete __cpuinit/__CPUINIT usage from all ARM users The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the ARM uses of the __cpuinit macros from C code, and all __CPUINIT from assembly code. It also had two ".previous" section statements that were paired off against __CPUINIT (aka .section ".cpuinit.text") that also get removed here. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-06-18 02:43:14 +07:00
static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
if (psci_ops.cpu_on)
return psci_ops.cpu_on(cpu_logical_map(cpu),
virt_to_idmap(&secondary_startup));
return -ENODEV;
}
#ifdef CONFIG_HOTPLUG_CPU
static int psci_cpu_disable(unsigned int cpu)
{
/* Fail early if we don't have CPU_OFF support */
if (!psci_ops.cpu_off)
return -EOPNOTSUPP;
/* Trusted OS will deny CPU_OFF */
if (psci_tos_resident_on(cpu))
return -EPERM;
return 0;
}
static void psci_cpu_die(unsigned int cpu)
{
u32 state = PSCI_POWER_STATE_TYPE_POWER_DOWN <<
PSCI_0_2_POWER_STATE_TYPE_SHIFT;
if (psci_ops.cpu_off)
psci_ops.cpu_off(state);
/* We should never return */
panic("psci: cpu %d failed to shutdown\n", cpu);
}
static int psci_cpu_kill(unsigned int cpu)
{
int err, i;
if (!psci_ops.affinity_info)
return 1;
/*
* cpu_kill could race with cpu_die and we can
* potentially end up declaring this cpu undead
* while it is dying. So, try again a few times.
*/
for (i = 0; i < 10; i++) {
err = psci_ops.affinity_info(cpu_logical_map(cpu), 0);
if (err == PSCI_0_2_AFFINITY_LEVEL_OFF) {
pr_info("CPU%d killed.\n", cpu);
return 1;
}
msleep(10);
pr_info("Retrying again to check for CPU kill\n");
}
pr_warn("CPU%d may not have shut down cleanly (AFFINITY_INFO reports %d)\n",
cpu, err);
/* Make platform_cpu_kill() fail. */
return 0;
}
#endif
bool __init psci_smp_available(void)
{
/* is cpu_on available at least? */
return (psci_ops.cpu_on != NULL);
}
const struct smp_operations psci_smp_ops __initconst = {
.smp_boot_secondary = psci_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_disable = psci_cpu_disable,
.cpu_die = psci_cpu_die,
.cpu_kill = psci_cpu_kill,
#endif
};