diff options
Diffstat (limited to 'arch/arc/include')
| -rw-r--r-- | arch/arc/include/asm/cache.h | 2 | ||||
| -rw-r--r-- | arch/arc/include/asm/entry-compact.h | 4 | ||||
| -rw-r--r-- | arch/arc/include/asm/jump_label.h | 72 | ||||
| -rw-r--r-- | arch/arc/include/asm/mmu.h | 6 | ||||
| -rw-r--r-- | arch/arc/include/asm/mmu_context.h | 2 | ||||
| -rw-r--r-- | arch/arc/include/asm/pgtable.h | 2 |
6 files changed, 84 insertions, 4 deletions
diff --git a/arch/arc/include/asm/cache.h b/arch/arc/include/asm/cache.h index 918804c7c1a4..d8ece4292388 100644 --- a/arch/arc/include/asm/cache.h +++ b/arch/arc/include/asm/cache.h @@ -25,6 +25,8 @@ #ifndef __ASSEMBLY__ +#include <linux/build_bug.h> + /* Uncached access macros */ #define arc_read_uncached_32(ptr) \ ({ \ diff --git a/arch/arc/include/asm/entry-compact.h b/arch/arc/include/asm/entry-compact.h index 66a292335ee6..c3aa775878dc 100644 --- a/arch/arc/include/asm/entry-compact.h +++ b/arch/arc/include/asm/entry-compact.h @@ -130,7 +130,7 @@ * to be saved again on kernel mode stack, as part of pt_regs. *-------------------------------------------------------------*/ .macro PROLOG_FREEUP_REG reg, mem -#ifdef CONFIG_SMP +#ifndef ARC_USE_SCRATCH_REG sr \reg, [ARC_REG_SCRATCH_DATA0] #else st \reg, [\mem] @@ -138,7 +138,7 @@ .endm .macro PROLOG_RESTORE_REG reg, mem -#ifdef CONFIG_SMP +#ifndef ARC_USE_SCRATCH_REG lr \reg, [ARC_REG_SCRATCH_DATA0] #else ld \reg, [\mem] diff --git a/arch/arc/include/asm/jump_label.h b/arch/arc/include/asm/jump_label.h new file mode 100644 index 000000000000..9d9618079739 --- /dev/null +++ b/arch/arc/include/asm/jump_label.h @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_ARC_JUMP_LABEL_H +#define _ASM_ARC_JUMP_LABEL_H + +#ifndef __ASSEMBLY__ + +#include <linux/stringify.h> +#include <linux/types.h> + +#define JUMP_LABEL_NOP_SIZE 4 + +/* + * NOTE about '.balign 4': + * + * To make atomic update of patched instruction available we need to guarantee + * that this instruction doesn't cross L1 cache line boundary. + * + * As of today we simply align instruction which can be patched by 4 byte using + * ".balign 4" directive. In that case patched instruction is aligned with one + * 16-bit NOP_S if this is required. + * However 'align by 4' directive is much stricter than it actually required. + * It's enough that our 32-bit instruction don't cross L1 cache line boundary / + * L1 I$ fetch block boundary which can be achieved by using + * ".bundle_align_mode" assembler directive. That will save us from adding + * useless NOP_S padding in most of the cases. + * + * TODO: switch to ".bundle_align_mode" directive using whin it will be + * supported by ARC toolchain. + */ + +static __always_inline bool arch_static_branch(struct static_key *key, + bool branch) +{ + asm_volatile_goto(".balign "__stringify(JUMP_LABEL_NOP_SIZE)" \n" + "1: \n" + "nop \n" + ".pushsection __jump_table, \"aw\" \n" + ".word 1b, %l[l_yes], %c0 \n" + ".popsection \n" + : : "i" (&((char *)key)[branch]) : : l_yes); + + return false; +l_yes: + return true; +} + +static __always_inline bool arch_static_branch_jump(struct static_key *key, + bool branch) +{ + asm_volatile_goto(".balign "__stringify(JUMP_LABEL_NOP_SIZE)" \n" + "1: \n" + "b %l[l_yes] \n" + ".pushsection __jump_table, \"aw\" \n" + ".word 1b, %l[l_yes], %c0 \n" + ".popsection \n" + : : "i" (&((char *)key)[branch]) : : l_yes); + + return false; +l_yes: + return true; +} + +typedef u32 jump_label_t; + +struct jump_entry { + jump_label_t code; + jump_label_t target; + jump_label_t key; +}; + +#endif /* __ASSEMBLY__ */ +#endif diff --git a/arch/arc/include/asm/mmu.h b/arch/arc/include/asm/mmu.h index 98cadf1a09ac..26b731d32a2b 100644 --- a/arch/arc/include/asm/mmu.h +++ b/arch/arc/include/asm/mmu.h @@ -40,6 +40,10 @@ #define ARC_REG_SCRATCH_DATA0 0x46c #endif +#if defined(CONFIG_ISA_ARCV2) || !defined(CONFIG_SMP) +#define ARC_USE_SCRATCH_REG +#endif + /* Bits in MMU PID register */ #define __TLB_ENABLE (1 << 31) #define __PROG_ENABLE (1 << 30) @@ -63,6 +67,8 @@ #if (CONFIG_ARC_MMU_VER >= 2) #define TLBWriteNI 0x5 /* write JTLB without inv uTLBs */ #define TLBIVUTLB 0x6 /* explicitly inv uTLBs */ +#else +#define TLBWriteNI TLBWrite /* Not present in hardware, fallback */ #endif #if (CONFIG_ARC_MMU_VER >= 4) diff --git a/arch/arc/include/asm/mmu_context.h b/arch/arc/include/asm/mmu_context.h index 035470816be5..3a5e6a5b9ed6 100644 --- a/arch/arc/include/asm/mmu_context.h +++ b/arch/arc/include/asm/mmu_context.h @@ -144,7 +144,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, */ cpumask_set_cpu(cpu, mm_cpumask(next)); -#ifndef CONFIG_SMP +#ifdef ARC_USE_SCRATCH_REG /* PGD cached in MMU reg to avoid 3 mem lookups: task->mm->pgd */ write_aux_reg(ARC_REG_SCRATCH_DATA0, next->pgd); #endif diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h index b917b596f7fb..9019ed9f9c94 100644 --- a/arch/arc/include/asm/pgtable.h +++ b/arch/arc/include/asm/pgtable.h @@ -350,7 +350,7 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, * Thus use this macro only when you are certain that "current" is current * e.g. when dealing with signal frame setup code etc */ -#ifndef CONFIG_SMP +#ifdef ARC_USE_SCRATCH_REG #define pgd_offset_fast(mm, addr) \ ({ \ pgd_t *pgd_base = (pgd_t *) read_aux_reg(ARC_REG_SCRATCH_DATA0); \ |