diff options
Diffstat (limited to 'arch/riscv/kernel/cpufeature.c')
| -rw-r--r-- | arch/riscv/kernel/cpufeature.c | 67 |
1 files changed, 58 insertions, 9 deletions
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 59d58ee0f68d..52585e088873 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -8,20 +8,15 @@ #include <linux/bitmap.h> #include <linux/ctype.h> -#include <linux/libfdt.h> #include <linux/log2.h> #include <linux/memory.h> #include <linux/module.h> #include <linux/of.h> #include <asm/alternative.h> #include <asm/cacheflush.h> -#include <asm/errata_list.h> #include <asm/hwcap.h> #include <asm/patch.h> -#include <asm/pgtable.h> #include <asm/processor.h> -#include <asm/smp.h> -#include <asm/switch_to.h> #define NUM_ALPHA_EXTS ('z' - 'a' + 1) @@ -30,6 +25,9 @@ unsigned long elf_hwcap __read_mostly; /* Host ISA bitmap */ static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly; +/* Performance information */ +DEFINE_PER_CPU(long, misaligned_access_speed); + /** * riscv_isa_extension_base() - Get base extension word * @@ -79,6 +77,15 @@ static bool riscv_isa_extension_check(int id) return false; } return true; + case RISCV_ISA_EXT_ZICBOZ: + if (!riscv_cboz_block_size) { + pr_err("Zicboz detected in ISA string, but no cboz-block-size found\n"); + return false; + } else if (!is_power_of_2(riscv_cboz_block_size)) { + pr_err("cboz-block-size present, but is not a power-of-2\n"); + return false; + } + return true; } return true; @@ -224,9 +231,11 @@ void __init riscv_fill_hwcap(void) SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF); SET_ISA_EXT_MAP("sstc", RISCV_ISA_EXT_SSTC); SET_ISA_EXT_MAP("svinval", RISCV_ISA_EXT_SVINVAL); + SET_ISA_EXT_MAP("svnapot", RISCV_ISA_EXT_SVNAPOT); SET_ISA_EXT_MAP("svpbmt", RISCV_ISA_EXT_SVPBMT); SET_ISA_EXT_MAP("zbb", RISCV_ISA_EXT_ZBB); SET_ISA_EXT_MAP("zicbom", RISCV_ISA_EXT_ZICBOM); + SET_ISA_EXT_MAP("zicboz", RISCV_ISA_EXT_ZICBOZ); SET_ISA_EXT_MAP("zihintpause", RISCV_ISA_EXT_ZIHINTPAUSE); } #undef SET_ISA_EXT_MAP @@ -269,12 +278,46 @@ void __init riscv_fill_hwcap(void) } #ifdef CONFIG_RISCV_ALTERNATIVE +/* + * Alternative patch sites consider 48 bits when determining when to patch + * the old instruction sequence with the new. These bits are broken into a + * 16-bit vendor ID and a 32-bit patch ID. A non-zero vendor ID means the + * patch site is for an erratum, identified by the 32-bit patch ID. When + * the vendor ID is zero, the patch site is for a cpufeature. cpufeatures + * further break down patch ID into two 16-bit numbers. The lower 16 bits + * are the cpufeature ID and the upper 16 bits are used for a value specific + * to the cpufeature and patch site. If the upper 16 bits are zero, then it + * implies no specific value is specified. cpufeatures that want to control + * patching on a per-site basis will provide non-zero values and implement + * checks here. The checks return true when patching should be done, and + * false otherwise. + */ +static bool riscv_cpufeature_patch_check(u16 id, u16 value) +{ + if (!value) + return true; + + switch (id) { + case RISCV_ISA_EXT_ZICBOZ: + /* + * Zicboz alternative applications provide the maximum + * supported block size order, or zero when it doesn't + * matter. If the current block size exceeds the maximum, + * then the alternative cannot be applied. + */ + return riscv_cboz_block_size <= (1U << value); + } + + return false; +} + void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin, struct alt_entry *end, unsigned int stage) { struct alt_entry *alt; void *oldptr, *altptr; + u16 id, value; if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) return; @@ -282,13 +325,19 @@ void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin, for (alt = begin; alt < end; alt++) { if (alt->vendor_id != 0) continue; - if (alt->errata_id >= RISCV_ISA_EXT_MAX) { - WARN(1, "This extension id:%d is not in ISA extension list", - alt->errata_id); + + id = PATCH_ID_CPUFEATURE_ID(alt->patch_id); + + if (id >= RISCV_ISA_EXT_MAX) { + WARN(1, "This extension id:%d is not in ISA extension list", id); continue; } - if (!__riscv_isa_extension_available(NULL, alt->errata_id)) + if (!__riscv_isa_extension_available(NULL, id)) + continue; + + value = PATCH_ID_CPUFEATURE_VALUE(alt->patch_id); + if (!riscv_cpufeature_patch_check(id, value)) continue; oldptr = ALT_OLD_PTR(alt); |