blob: 6f6801da9dc1e26336e2bd8d59ab0f5085e349c5 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
*
* Modifications for ppc64:
* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
*/
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/threads.h>
#include <linux/init.h>
#include <linux/export.h>
#include <linux/jump_label.h>
#include <linux/of.h>
#include <asm/cputable.h>
#include <asm/mce.h>
#include <asm/mmu.h>
#include <asm/setup.h>
#include <asm/cpu_setup.h>
static struct cpu_spec the_cpu_spec __ro_after_init;
struct cpu_spec *cur_cpu_spec __ro_after_init = NULL;
EXPORT_SYMBOL(cur_cpu_spec);
/* The platform string corresponding to the real PVR */
const char *powerpc_base_platform;
#include "cpu_specs.h"
void __init set_cur_cpu_spec(struct cpu_spec *s)
{
struct cpu_spec *t = &the_cpu_spec;
t = PTRRELOC(t);
/*
* use memcpy() instead of *t = *s so that GCC replaces it
* by __memcpy() when KASAN is active
*/
memcpy(t, s, sizeof(*t));
*PTRRELOC(&cur_cpu_spec) = &the_cpu_spec;
}
static struct cpu_spec * __init setup_cpu_spec(unsigned long offset,
struct cpu_spec *s)
{
struct cpu_spec *t = &the_cpu_spec;
struct cpu_spec old;
t = PTRRELOC(t);
old = *t;
/*
* Copy everything, then do fixups. Use memcpy() instead of *t = *s
* so that GCC replaces it by __memcpy() when KASAN is active
*/
memcpy(t, s, sizeof(*t));
/*
* If we are overriding a previous value derived from the real
* PVR with a new value obtained using a logical PVR value,
* don't modify the performance monitor fields.
*/
if (old.num_pmcs && !s->num_pmcs) {
t->num_pmcs = old.num_pmcs;
t->pmc_type = old.pmc_type;
/*
* Let's ensure that the
* fix for the PMAO bug is enabled on compatibility mode.
*/
t->cpu_features |= old.cpu_features & CPU_FTR_PMAO_BUG;
}
/* Set kuap ON at startup, will be disabled later if cmdline has 'nosmap' */
if (IS_ENABLED(CONFIG_PPC_KUAP) && IS_ENABLED(CONFIG_PPC32))
t->mmu_features |= MMU_FTR_KUAP;
*PTRRELOC(&cur_cpu_spec) = &the_cpu_spec;
/*
* Set the base platform string once; assumes
* we're called with real pvr first.
*/
if (*PTRRELOC(&powerpc_base_platform) == NULL)
*PTRRELOC(&powerpc_base_platform) = t->platform;
#if defined(CONFIG_PPC64) || defined(CONFIG_BOOKE)
/* ppc64 and booke expect identify_cpu to also call setup_cpu for
* that processor. I will consolidate that at a later time, for now,
* just use #ifdef. We also don't need to PTRRELOC the function
* pointer on ppc64 and booke as we are running at 0 in real mode
* on ppc64 and reloc_offset is always 0 on booke.
*/
if (t->cpu_setup) {
t->cpu_setup(offset, t);
}
#endif /* CONFIG_PPC64 || CONFIG_BOOKE */
return t;
}
struct cpu_spec * __init identify_cpu(unsigned long offset, unsigned int pvr)
{
struct cpu_spec *s = cpu_specs;
int i;
BUILD_BUG_ON(!ARRAY_SIZE(cpu_specs));
s = PTRRELOC(s);
for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) {
if ((pvr & s->pvr_mask) == s->pvr_value)
return setup_cpu_spec(offset, s);
}
BUG();
return NULL;
}
/*
* Used by cpufeatures to get the name for CPUs with a PVR table.
* If they don't hae a PVR table, cpufeatures gets the name from
* cpu device-tree node.
*/
void __init identify_cpu_name(unsigned int pvr)
{
struct cpu_spec *s = cpu_specs;
struct cpu_spec *t = &the_cpu_spec;
int i;
s = PTRRELOC(s);
t = PTRRELOC(t);
for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) {
if ((pvr & s->pvr_mask) == s->pvr_value) {
t->cpu_name = s->cpu_name;
return;
}
}
}
#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS
struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS] = {
[0 ... NUM_CPU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT
};
EXPORT_SYMBOL_GPL(cpu_feature_keys);
void __init cpu_feature_keys_init(void)
{
int i;
for (i = 0; i < NUM_CPU_FTR_KEYS; i++) {
unsigned long f = 1ul << i;
if (!(cur_cpu_spec->cpu_features & f))
static_branch_disable(&cpu_feature_keys[i]);
}
}
struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS] = {
[0 ... NUM_MMU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT
};
EXPORT_SYMBOL(mmu_feature_keys);
void __init mmu_feature_keys_init(void)
{
int i;
for (i = 0; i < NUM_MMU_FTR_KEYS; i++) {
unsigned long f = 1ul << i;
if (!(cur_cpu_spec->mmu_features & f))
static_branch_disable(&mmu_feature_keys[i]);
}
}
#endif