diff options
author | Catalin Marinas <catalin.marinas@arm.com> | 2020-07-31 18:09:50 +0100 |
---|---|---|
committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-07-31 18:09:50 +0100 |
commit | 18aa3bd58b1428d1927fe11f85ad444423d4fc59 (patch) | |
tree | 40171776fd498d9ae9378c9559fcada83c92ee17 /arch/arm64/include/asm/tlbflush.h | |
parent | 4557062da7ebfa9236af83fcb4323a1838ae533e (diff) | |
parent | d1d3aa98b1d4826a19adfefb69b96142a0cac633 (diff) | |
download | linux-18aa3bd58b1428d1927fe11f85ad444423d4fc59.tar.bz2 |
Merge branch 'for-next/tlbi' into for-next/core
* for-next/tlbi:
: Support for TTL (translation table level) hint in the TLB operations
arm64: tlb: Use the TLBI RANGE feature in arm64
arm64: enable tlbi range instructions
arm64: tlb: Detect the ARMv8.4 TLBI RANGE feature
arm64: tlb: don't set the ttl value in flush_tlb_page_nosync
arm64: Shift the __tlbi_level() indentation left
arm64: tlb: Set the TTL field in flush_*_tlb_range
arm64: tlb: Set the TTL field in flush_tlb_range
tlb: mmu_gather: add tlb_flush_*_range APIs
arm64: Add tlbi_user_level TLB invalidation helper
arm64: Add level-hinted TLB invalidation helper
arm64: Document SW reserved PTE/PMD bits in Stage-2 descriptors
arm64: Detect the ARMv8.4 TTL feature
Diffstat (limited to 'arch/arm64/include/asm/tlbflush.h')
-rw-r--r-- | arch/arm64/include/asm/tlbflush.h | 177 |
1 files changed, 162 insertions, 15 deletions
diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index bc3949064725..d493174415db 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -10,6 +10,7 @@ #ifndef __ASSEMBLY__ +#include <linux/bitfield.h> #include <linux/mm_types.h> #include <linux/sched.h> #include <asm/cputype.h> @@ -60,6 +61,102 @@ }) /* + * Get translation granule of the system, which is decided by + * PAGE_SIZE. Used by TTL. + * - 4KB : 1 + * - 16KB : 2 + * - 64KB : 3 + */ +#define TLBI_TTL_TG_4K 1 +#define TLBI_TTL_TG_16K 2 +#define TLBI_TTL_TG_64K 3 + +static inline unsigned long get_trans_granule(void) +{ + switch (PAGE_SIZE) { + case SZ_4K: + return TLBI_TTL_TG_4K; + case SZ_16K: + return TLBI_TTL_TG_16K; + case SZ_64K: + return TLBI_TTL_TG_64K; + default: + return 0; + } +} + +/* + * Level-based TLBI operations. + * + * When ARMv8.4-TTL exists, TLBI operations take an additional hint for + * the level at which the invalidation must take place. If the level is + * wrong, no invalidation may take place. In the case where the level + * cannot be easily determined, a 0 value for the level parameter will + * perform a non-hinted invalidation. + * + * For Stage-2 invalidation, use the level values provided to that effect + * in asm/stage2_pgtable.h. + */ +#define TLBI_TTL_MASK GENMASK_ULL(47, 44) + +#define __tlbi_level(op, addr, level) do { \ + u64 arg = addr; \ + \ + if (cpus_have_const_cap(ARM64_HAS_ARMv8_4_TTL) && \ + level) { \ + u64 ttl = level & 3; \ + ttl |= get_trans_granule() << 2; \ + arg &= ~TLBI_TTL_MASK; \ + arg |= FIELD_PREP(TLBI_TTL_MASK, ttl); \ + } \ + \ + __tlbi(op, arg); \ +} while(0) + +#define __tlbi_user_level(op, arg, level) do { \ + if (arm64_kernel_unmapped_at_el0()) \ + __tlbi_level(op, (arg | USER_ASID_FLAG), level); \ +} while (0) + +/* + * This macro creates a properly formatted VA operand for the TLB RANGE. + * The value bit assignments are: + * + * +----------+------+-------+-------+-------+----------------------+ + * | ASID | TG | SCALE | NUM | TTL | BADDR | + * +-----------------+-------+-------+-------+----------------------+ + * |63 48|47 46|45 44|43 39|38 37|36 0| + * + * The address range is determined by below formula: + * [BADDR, BADDR + (NUM + 1) * 2^(5*SCALE + 1) * PAGESIZE) + * + */ +#define __TLBI_VADDR_RANGE(addr, asid, scale, num, ttl) \ + ({ \ + unsigned long __ta = (addr) >> PAGE_SHIFT; \ + __ta &= GENMASK_ULL(36, 0); \ + __ta |= (unsigned long)(ttl) << 37; \ + __ta |= (unsigned long)(num) << 39; \ + __ta |= (unsigned long)(scale) << 44; \ + __ta |= get_trans_granule() << 46; \ + __ta |= (unsigned long)(asid) << 48; \ + __ta; \ + }) + +/* These macros are used by the TLBI RANGE feature. */ +#define __TLBI_RANGE_PAGES(num, scale) \ + ((unsigned long)((num) + 1) << (5 * (scale) + 1)) +#define MAX_TLBI_RANGE_PAGES __TLBI_RANGE_PAGES(31, 3) + +/* + * Generate 'num' values from -1 to 30 with -1 rejected by the + * __flush_tlb_range() loop below. + */ +#define TLBI_RANGE_MASK GENMASK_ULL(4, 0) +#define __TLBI_RANGE_NUM(pages, scale) \ + ((((pages) >> (5 * (scale) + 1)) & TLBI_RANGE_MASK) - 1) + +/* * TLB Invalidation * ================ * @@ -179,34 +276,83 @@ static inline void flush_tlb_page(struct vm_area_struct *vma, static inline void __flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, - unsigned long stride, bool last_level) + unsigned long stride, bool last_level, + int tlb_level) { + int num = 0; + int scale = 0; unsigned long asid = ASID(vma->vm_mm); unsigned long addr; + unsigned long pages; start = round_down(start, stride); end = round_up(end, stride); + pages = (end - start) >> PAGE_SHIFT; - if ((end - start) >= (MAX_TLBI_OPS * stride)) { + /* + * When not uses TLB range ops, we can handle up to + * (MAX_TLBI_OPS - 1) pages; + * When uses TLB range ops, we can handle up to + * (MAX_TLBI_RANGE_PAGES - 1) pages. + */ + if ((!system_supports_tlb_range() && + (end - start) >= (MAX_TLBI_OPS * stride)) || + pages >= MAX_TLBI_RANGE_PAGES) { flush_tlb_mm(vma->vm_mm); return; } - /* Convert the stride into units of 4k */ - stride >>= 12; + dsb(ishst); - start = __TLBI_VADDR(start, asid); - end = __TLBI_VADDR(end, asid); + /* + * When the CPU does not support TLB range operations, flush the TLB + * entries one by one at the granularity of 'stride'. If the the TLB + * range ops are supported, then: + * + * 1. If 'pages' is odd, flush the first page through non-range + * operations; + * + * 2. For remaining pages: the minimum range granularity is decided + * by 'scale', so multiple range TLBI operations may be required. + * Start from scale = 0, flush the corresponding number of pages + * ((num+1)*2^(5*scale+1) starting from 'addr'), then increase it + * until no pages left. + * + * Note that certain ranges can be represented by either num = 31 and + * scale or num = 0 and scale + 1. The loop below favours the latter + * since num is limited to 30 by the __TLBI_RANGE_NUM() macro. + */ + while (pages > 0) { + if (!system_supports_tlb_range() || + pages % 2 == 1) { + addr = __TLBI_VADDR(start, asid); + if (last_level) { + __tlbi_level(vale1is, addr, tlb_level); + __tlbi_user_level(vale1is, addr, tlb_level); + } else { + __tlbi_level(vae1is, addr, tlb_level); + __tlbi_user_level(vae1is, addr, tlb_level); + } + start += stride; + pages -= stride >> PAGE_SHIFT; + continue; + } - dsb(ishst); - for (addr = start; addr < end; addr += stride) { - if (last_level) { - __tlbi(vale1is, addr); - __tlbi_user(vale1is, addr); - } else { - __tlbi(vae1is, addr); - __tlbi_user(vae1is, addr); + num = __TLBI_RANGE_NUM(pages, scale); + if (num >= 0) { + addr = __TLBI_VADDR_RANGE(start, asid, scale, + num, tlb_level); + if (last_level) { + __tlbi(rvale1is, addr); + __tlbi_user(rvale1is, addr); + } else { + __tlbi(rvae1is, addr); + __tlbi_user(rvae1is, addr); + } + start += __TLBI_RANGE_PAGES(num, scale) << PAGE_SHIFT; + pages -= __TLBI_RANGE_PAGES(num, scale); } + scale++; } dsb(ish); } @@ -217,8 +363,9 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, /* * We cannot use leaf-only invalidation here, since we may be invalidating * table entries as part of collapsing hugepages or moving page tables. + * Set the tlb_level to 0 because we can not get enough information here. */ - __flush_tlb_range(vma, start, end, PAGE_SIZE, false); + __flush_tlb_range(vma, start, end, PAGE_SIZE, false, 0); } static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end) |