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Diffstat (limited to '')
| -rw-r--r-- | arch/arc/lib/memset-archs.S | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/arc/lib/memset-archs.S b/arch/arc/lib/memset-archs.S new file mode 100644 index 000000000..d2e09fece --- /dev/null +++ b/arch/arc/lib/memset-archs.S @@ -0,0 +1,143 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/linkage.h> +#include <asm/cache.h> + +/* + * The memset implementation below is optimized to use prefetchw and prealloc + * instruction in case of CPU with 64B L1 data cache line (L1_CACHE_SHIFT == 6) + * If you want to implement optimized memset for other possible L1 data cache + * line lengths (32B and 128B) you should rewrite code carefully checking + * we don't call any prefetchw/prealloc instruction for L1 cache lines which + * don't belongs to memset area. + */ + +#if L1_CACHE_SHIFT == 6 + +.macro PREALLOC_INSTR reg, off + prealloc [\reg, \off] +.endm + +.macro PREFETCHW_INSTR reg, off + prefetchw [\reg, \off] +.endm + +#else + +.macro PREALLOC_INSTR reg, off +.endm + +.macro PREFETCHW_INSTR reg, off +.endm + +#endif + +ENTRY_CFI(memset) + PREFETCHW_INSTR r0, 0 ; Prefetch the first write location + mov.f 0, r2 +;;; if size is zero + jz.d [blink] + mov r3, r0 ; don't clobber ret val + +;;; if length < 8 + brls.d.nt r2, 8, .Lsmallchunk + mov.f lp_count,r2 + + and.f r4, r0, 0x03 + rsub lp_count, r4, 4 + lpnz @.Laligndestination + ;; LOOP BEGIN + stb.ab r1, [r3,1] + sub r2, r2, 1 +.Laligndestination: + +;;; Destination is aligned + and r1, r1, 0xFF + asl r4, r1, 8 + or r4, r4, r1 + asl r5, r4, 16 + or r5, r5, r4 + mov r4, r5 + + sub3 lp_count, r2, 8 + cmp r2, 64 + bmsk.hi r2, r2, 5 + mov.ls lp_count, 0 + add3.hi r2, r2, 8 + +;;; Convert len to Dwords, unfold x8 + lsr.f lp_count, lp_count, 6 + + lpnz @.Lset64bytes + ;; LOOP START + PREALLOC_INSTR r3, 64 ; alloc next line w/o fetching + +#ifdef CONFIG_ARC_HAS_LL64 + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] +#else + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] +#endif +.Lset64bytes: + + lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes + lpnz .Lset32bytes + ;; LOOP START +#ifdef CONFIG_ARC_HAS_LL64 + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] + std.ab r4, [r3, 8] +#else + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] +#endif +.Lset32bytes: + + and.f lp_count, r2, 0x1F ;Last remaining 31 bytes +.Lsmallchunk: + lpnz .Lcopy3bytes + ;; LOOP START + stb.ab r1, [r3, 1] +.Lcopy3bytes: + + j [blink] + +END_CFI(memset) + +ENTRY_CFI(memzero) + ; adjust bzero args to memset args + mov r2, r1 + b.d memset ;tail call so need to tinker with blink + mov r1, 0 +END_CFI(memzero) |