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Diffstat (limited to 'arch/powerpc/kernel/cputable.c')
| -rw-r--r-- | arch/powerpc/kernel/cputable.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c new file mode 100644 index 000000000..e97a0fd0a --- /dev/null +++ b/arch/powerpc/kernel/cputable.c @@ -0,0 +1,182 @@ +// 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 __read_mostly; + +struct cpu_spec* cur_cpu_spec __read_mostly = 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 |