cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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mcpm_platsmp.c (2204B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * linux/arch/arm/mach-vexpress/mcpm_platsmp.c
      4 *
      5 * Created by:  Nicolas Pitre, November 2012
      6 * Copyright:   (C) 2012-2013  Linaro Limited
      7 *
      8 * Code to handle secondary CPU bringup and hotplug for the cluster power API.
      9 */
     10
     11#include <linux/init.h>
     12#include <linux/smp.h>
     13#include <linux/spinlock.h>
     14
     15#include <asm/mcpm.h>
     16#include <asm/smp.h>
     17#include <asm/smp_plat.h>
     18
     19static void cpu_to_pcpu(unsigned int cpu,
     20			unsigned int *pcpu, unsigned int *pcluster)
     21{
     22	unsigned int mpidr;
     23
     24	mpidr = cpu_logical_map(cpu);
     25	*pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
     26	*pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
     27}
     28
     29static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle)
     30{
     31	unsigned int pcpu, pcluster, ret;
     32	extern void secondary_startup(void);
     33
     34	cpu_to_pcpu(cpu, &pcpu, &pcluster);
     35
     36	pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
     37		 __func__, cpu, pcpu, pcluster);
     38
     39	mcpm_set_entry_vector(pcpu, pcluster, NULL);
     40	ret = mcpm_cpu_power_up(pcpu, pcluster);
     41	if (ret)
     42		return ret;
     43	mcpm_set_entry_vector(pcpu, pcluster, secondary_startup);
     44	arch_send_wakeup_ipi_mask(cpumask_of(cpu));
     45	dsb_sev();
     46	return 0;
     47}
     48
     49static void mcpm_secondary_init(unsigned int cpu)
     50{
     51	mcpm_cpu_powered_up();
     52}
     53
     54#ifdef CONFIG_HOTPLUG_CPU
     55
     56static int mcpm_cpu_kill(unsigned int cpu)
     57{
     58	unsigned int pcpu, pcluster;
     59
     60	cpu_to_pcpu(cpu, &pcpu, &pcluster);
     61
     62	return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster);
     63}
     64
     65static bool mcpm_cpu_can_disable(unsigned int cpu)
     66{
     67	/* We assume all CPUs may be shut down. */
     68	return true;
     69}
     70
     71static void mcpm_cpu_die(unsigned int cpu)
     72{
     73	unsigned int mpidr, pcpu, pcluster;
     74	mpidr = read_cpuid_mpidr();
     75	pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
     76	pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
     77	mcpm_set_entry_vector(pcpu, pcluster, NULL);
     78	mcpm_cpu_power_down();
     79}
     80
     81#endif
     82
     83static const struct smp_operations mcpm_smp_ops __initconst = {
     84	.smp_boot_secondary	= mcpm_boot_secondary,
     85	.smp_secondary_init	= mcpm_secondary_init,
     86#ifdef CONFIG_HOTPLUG_CPU
     87	.cpu_kill		= mcpm_cpu_kill,
     88	.cpu_can_disable	= mcpm_cpu_can_disable,
     89	.cpu_die		= mcpm_cpu_die,
     90#endif
     91};
     92
     93void __init mcpm_smp_set_ops(void)
     94{
     95	smp_set_ops(&mcpm_smp_ops);
     96}