forked from Minki/linux
94a9e04aa1
Add a new item to the feature set (ARM64_HAS_SYSREG_GIC_CPUIF) to indicate that we have a system register GIC CPU interface This will help KVM switching to alternative instruction patching. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
64 lines
1.6 KiB
C
64 lines
1.6 KiB
C
/*
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* Contains CPU feature definitions
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*
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* Copyright (C) 2015 ARM Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#define pr_fmt(fmt) "alternatives: " fmt
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#include <linux/types.h>
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#include <asm/cpu.h>
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#include <asm/cpufeature.h>
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static bool
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has_id_aa64pfr0_feature(const struct arm64_cpu_capabilities *entry)
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{
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u64 val;
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val = read_cpuid(id_aa64pfr0_el1);
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return (val & entry->register_mask) == entry->register_value;
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}
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static const struct arm64_cpu_capabilities arm64_features[] = {
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{
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.desc = "GIC system register CPU interface",
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.capability = ARM64_HAS_SYSREG_GIC_CPUIF,
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.matches = has_id_aa64pfr0_feature,
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.register_mask = (0xf << 24),
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.register_value = (1 << 24),
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},
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{},
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};
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void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
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const char *info)
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{
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int i;
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for (i = 0; caps[i].desc; i++) {
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if (!caps[i].matches(&caps[i]))
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continue;
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if (!cpus_have_cap(caps[i].capability))
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pr_info("%s %s\n", info, caps[i].desc);
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cpus_set_cap(caps[i].capability);
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}
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}
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void check_local_cpu_features(void)
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{
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check_cpu_capabilities(arm64_features, "detected feature");
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}
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