diff options
Diffstat (limited to 'arch/arm64/kernel/setup.c')
| -rw-r--r-- | arch/arm64/kernel/setup.c | 122 |
1 files changed, 117 insertions, 5 deletions
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index bd9bbd0e44ed..c8e9effe52e1 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -108,20 +108,95 @@ void __init early_print(const char *str, ...) printk("%s", buf); } +void __init smp_setup_processor_id(void) +{ + /* + * clear __my_cpu_offset on boot CPU to avoid hang caused by + * using percpu variable early, for example, lockdep will + * access percpu variable inside lock_release + */ + set_my_cpu_offset(0); +} + bool arch_match_cpu_phys_id(int cpu, u64 phys_id) { return phys_id == cpu_logical_map(cpu); } +struct mpidr_hash mpidr_hash; +#ifdef CONFIG_SMP +/** + * smp_build_mpidr_hash - Pre-compute shifts required at each affinity + * level in order to build a linear index from an + * MPIDR value. Resulting algorithm is a collision + * free hash carried out through shifting and ORing + */ +static void __init smp_build_mpidr_hash(void) +{ + u32 i, affinity, fs[4], bits[4], ls; + u64 mask = 0; + /* + * Pre-scan the list of MPIDRS and filter out bits that do + * not contribute to affinity levels, ie they never toggle. + */ + for_each_possible_cpu(i) + mask |= (cpu_logical_map(i) ^ cpu_logical_map(0)); + pr_debug("mask of set bits %#llx\n", mask); + /* + * Find and stash the last and first bit set at all affinity levels to + * check how many bits are required to represent them. + */ + for (i = 0; i < 4; i++) { + affinity = MPIDR_AFFINITY_LEVEL(mask, i); + /* + * Find the MSB bit and LSB bits position + * to determine how many bits are required + * to express the affinity level. + */ + ls = fls(affinity); + fs[i] = affinity ? ffs(affinity) - 1 : 0; + bits[i] = ls - fs[i]; + } + /* + * An index can be created from the MPIDR_EL1 by isolating the + * significant bits at each affinity level and by shifting + * them in order to compress the 32 bits values space to a + * compressed set of values. This is equivalent to hashing + * the MPIDR_EL1 through shifting and ORing. It is a collision free + * hash though not minimal since some levels might contain a number + * of CPUs that is not an exact power of 2 and their bit + * representation might contain holes, eg MPIDR_EL1[7:0] = {0x2, 0x80}. + */ + mpidr_hash.shift_aff[0] = MPIDR_LEVEL_SHIFT(0) + fs[0]; + mpidr_hash.shift_aff[1] = MPIDR_LEVEL_SHIFT(1) + fs[1] - bits[0]; + mpidr_hash.shift_aff[2] = MPIDR_LEVEL_SHIFT(2) + fs[2] - + (bits[1] + bits[0]); + mpidr_hash.shift_aff[3] = MPIDR_LEVEL_SHIFT(3) + + fs[3] - (bits[2] + bits[1] + bits[0]); + mpidr_hash.mask = mask; + mpidr_hash.bits = bits[3] + bits[2] + bits[1] + bits[0]; + pr_debug("MPIDR hash: aff0[%u] aff1[%u] aff2[%u] aff3[%u] mask[%#llx] bits[%u]\n", + mpidr_hash.shift_aff[0], + mpidr_hash.shift_aff[1], + mpidr_hash.shift_aff[2], + mpidr_hash.shift_aff[3], + mpidr_hash.mask, + mpidr_hash.bits); + /* + * 4x is an arbitrary value used to warn on a hash table much bigger + * than expected on most systems. + */ + if (mpidr_hash_size() > 4 * num_possible_cpus()) + pr_warn("Large number of MPIDR hash buckets detected\n"); + __flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash)); +} +#endif + static void __init setup_processor(void) { struct cpu_info *cpu_info; + u64 features, block; - /* - * locate processor in the list of supported processor - * types. The linker builds this table for us from the - * entries in arch/arm/mm/proc.S - */ cpu_info = lookup_processor_type(read_cpuid_id()); if (!cpu_info) { printk("CPU configuration botched (ID %08x), unable to continue.\n", @@ -136,6 +211,37 @@ static void __init setup_processor(void) sprintf(init_utsname()->machine, ELF_PLATFORM); elf_hwcap = 0; + + /* + * ID_AA64ISAR0_EL1 contains 4-bit wide signed feature blocks. + * The blocks we test below represent incremental functionality + * for non-negative values. Negative values are reserved. + */ + features = read_cpuid(ID_AA64ISAR0_EL1); + block = (features >> 4) & 0xf; + if (!(block & 0x8)) { + switch (block) { + default: + case 2: + elf_hwcap |= HWCAP_PMULL; + case 1: + elf_hwcap |= HWCAP_AES; + case 0: + break; + } + } + + block = (features >> 8) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_SHA1; + + block = (features >> 12) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_SHA2; + + block = (features >> 16) & 0xf; + if (block && !(block & 0x8)) + elf_hwcap |= HWCAP_CRC32; } static void __init setup_machine_fdt(phys_addr_t dt_phys) @@ -236,6 +342,7 @@ void __init setup_arch(char **cmdline_p) cpu_read_bootcpu_ops(); #ifdef CONFIG_SMP smp_init_cpus(); + smp_build_mpidr_hash(); #endif #ifdef CONFIG_VT @@ -275,6 +382,11 @@ static const char *hwcap_str[] = { "fp", "asimd", "evtstrm", + "aes", + "pmull", + "sha1", + "sha2", + "crc32", NULL }; |