diff options
author | Zong Li <zong.li@sifive.com> | 2020-08-31 15:33:50 +0800 |
---|---|---|
committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2020-09-15 18:46:08 -0700 |
commit | 38f5bd23deae24c8fa67a2c574b6d43df27a8aa8 (patch) | |
tree | 5d0762eb60036e15eef0d2a79497e594ee88923f | |
parent | b5fca7c55f9fbab5ad732c3bce00f31af6ba5cfa (diff) | |
download | linux-38f5bd23deae24c8fa67a2c574b6d43df27a8aa8.tar.bz2 |
riscv: Add cache information in AUX vector
There are no standard CSR registers to provide cache information, the
way for RISC-V is to get this information from DT. Currently, AT_L1I_X,
AT_L1D_X and AT_L2_X are present in glibc header, and sysconf syscall
could use them to get information of cache through AUX vector.
The result of 'getconf -a' as follows:
LEVEL1_ICACHE_SIZE 32768
LEVEL1_ICACHE_ASSOC 8
LEVEL1_ICACHE_LINESIZE 64
LEVEL1_DCACHE_SIZE 32768
LEVEL1_DCACHE_ASSOC 8
LEVEL1_DCACHE_LINESIZE 64
LEVEL2_CACHE_SIZE 2097152
LEVEL2_CACHE_ASSOC 32
LEVEL2_CACHE_LINESIZE 64
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
-rw-r--r-- | arch/riscv/include/asm/cacheinfo.h | 5 | ||||
-rw-r--r-- | arch/riscv/include/asm/elf.h | 13 | ||||
-rw-r--r-- | arch/riscv/include/uapi/asm/auxvec.h | 23 | ||||
-rw-r--r-- | arch/riscv/kernel/cacheinfo.c | 32 |
4 files changed, 71 insertions, 2 deletions
diff --git a/arch/riscv/include/asm/cacheinfo.h b/arch/riscv/include/asm/cacheinfo.h index 5d9662e9aba8..d1a365215ec0 100644 --- a/arch/riscv/include/asm/cacheinfo.h +++ b/arch/riscv/include/asm/cacheinfo.h @@ -1,4 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 SiFive + */ #ifndef _ASM_RISCV_CACHEINFO_H #define _ASM_RISCV_CACHEINFO_H @@ -11,5 +14,7 @@ struct riscv_cacheinfo_ops { }; void riscv_set_cacheinfo_ops(struct riscv_cacheinfo_ops *ops); +uintptr_t get_cache_size(u32 level, enum cache_type type); +uintptr_t get_cache_geometry(u32 level, enum cache_type type); #endif /* _ASM_RISCV_CACHEINFO_H */ diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index d83a4efd052b..5c725e1df58b 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -11,6 +11,7 @@ #include <uapi/asm/elf.h> #include <asm/auxvec.h> #include <asm/byteorder.h> +#include <asm/cacheinfo.h> /* * These are used to set parameters in the core dumps. @@ -61,6 +62,18 @@ extern unsigned long elf_hwcap; do { \ NEW_AUX_ENT(AT_SYSINFO_EHDR, \ (elf_addr_t)current->mm->context.vdso); \ + NEW_AUX_ENT(AT_L1I_CACHESIZE, \ + get_cache_size(1, CACHE_TYPE_INST)); \ + NEW_AUX_ENT(AT_L1I_CACHEGEOMETRY, \ + get_cache_geometry(1, CACHE_TYPE_INST)); \ + NEW_AUX_ENT(AT_L1D_CACHESIZE, \ + get_cache_size(1, CACHE_TYPE_DATA)); \ + NEW_AUX_ENT(AT_L1D_CACHEGEOMETRY, \ + get_cache_geometry(1, CACHE_TYPE_DATA)); \ + NEW_AUX_ENT(AT_L2_CACHESIZE, \ + get_cache_size(2, CACHE_TYPE_UNIFIED)); \ + NEW_AUX_ENT(AT_L2_CACHEGEOMETRY, \ + get_cache_geometry(2, CACHE_TYPE_UNIFIED)); \ } while (0) #define ARCH_HAS_SETUP_ADDITIONAL_PAGES struct linux_binprm; diff --git a/arch/riscv/include/uapi/asm/auxvec.h b/arch/riscv/include/uapi/asm/auxvec.h index 22e0ae888406..32c73ba1d531 100644 --- a/arch/riscv/include/uapi/asm/auxvec.h +++ b/arch/riscv/include/uapi/asm/auxvec.h @@ -10,7 +10,28 @@ /* vDSO location */ #define AT_SYSINFO_EHDR 33 +/* + * The set of entries below represent more extensive information + * about the caches, in the form of two entry per cache type, + * one entry containing the cache size in bytes, and the other + * containing the cache line size in bytes in the bottom 16 bits + * and the cache associativity in the next 16 bits. + * + * The associativity is such that if N is the 16-bit value, the + * cache is N way set associative. A value if 0xffff means fully + * associative, a value of 1 means directly mapped. + * + * For all these fields, a value of 0 means that the information + * is not known. + */ +#define AT_L1I_CACHESIZE 40 +#define AT_L1I_CACHEGEOMETRY 41 +#define AT_L1D_CACHESIZE 42 +#define AT_L1D_CACHEGEOMETRY 43 +#define AT_L2_CACHESIZE 44 +#define AT_L2_CACHEGEOMETRY 45 + /* entries in ARCH_DLINFO */ -#define AT_VECTOR_SIZE_ARCH 1 +#define AT_VECTOR_SIZE_ARCH 7 #endif /* _UAPI_ASM_RISCV_AUXVEC_H */ diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c index 291d7d8f748b..de59dd457b41 100644 --- a/arch/riscv/kernel/cacheinfo.c +++ b/arch/riscv/kernel/cacheinfo.c @@ -3,7 +3,6 @@ * Copyright (C) 2017 SiFive */ -#include <linux/cacheinfo.h> #include <linux/cpu.h> #include <linux/of.h> #include <linux/of_device.h> @@ -25,6 +24,37 @@ cache_get_priv_group(struct cacheinfo *this_leaf) return NULL; } +static struct cacheinfo *get_cacheinfo(u32 level, enum cache_type type) +{ + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(smp_processor_id()); + struct cacheinfo *this_leaf; + int index; + + for (index = 0; index < this_cpu_ci->num_leaves; index++) { + this_leaf = this_cpu_ci->info_list + index; + if (this_leaf->level == level && this_leaf->type == type) + return this_leaf; + } + + return NULL; +} + +uintptr_t get_cache_size(u32 level, enum cache_type type) +{ + struct cacheinfo *this_leaf = get_cacheinfo(level, type); + + return this_leaf ? this_leaf->size : 0; +} + +uintptr_t get_cache_geometry(u32 level, enum cache_type type) +{ + struct cacheinfo *this_leaf = get_cacheinfo(level, type); + + return this_leaf ? (this_leaf->ways_of_associativity << 16 | + this_leaf->coherency_line_size) : + 0; +} + static void ci_leaf_init(struct cacheinfo *this_leaf, enum cache_type type, unsigned int level, unsigned int size, unsigned int sets, unsigned int line_size) |