From 930bff882296c02ca81db108672ef4ca06c37db5 Mon Sep 17 00:00:00 2001 From: Thomas Bogendoerfer Date: Sun, 25 Nov 2007 11:47:56 +0100 Subject: [PATCH] [MIPS] IP28: added cache barrier to assembly routines IP28 needs special treatment to avoid speculative accesses. gcc takes care for .c code, but for assembly code we need to do it manually. This is taken from Peter Fuersts IP28 patches. Signed-off-by: Thomas Bogendoerfer Signed-off-by: Ralf Baechle --- arch/mips/lib/memcpy.S | 10 ++++++++++ arch/mips/lib/memset.S | 5 +++++ arch/mips/lib/strncpy_user.S | 1 + include/asm-mips/asm.h | 8 ++++++++ 4 files changed, 24 insertions(+) diff --git a/arch/mips/lib/memcpy.S b/arch/mips/lib/memcpy.S index aded7b1590..01e450b1eb 100644 --- a/arch/mips/lib/memcpy.S +++ b/arch/mips/lib/memcpy.S @@ -199,6 +199,7 @@ FEXPORT(__copy_user) */ #define rem t8 + R10KCBARRIER(0(ra)) /* * The "issue break"s below are very approximate. * Issue delays for dcache fills will perturb the schedule, as will @@ -231,6 +232,7 @@ both_aligned: PREF( 1, 3*32(dst) ) .align 4 1: + R10KCBARRIER(0(ra)) EXC( LOAD t0, UNIT(0)(src), l_exc) EXC( LOAD t1, UNIT(1)(src), l_exc_copy) EXC( LOAD t2, UNIT(2)(src), l_exc_copy) @@ -272,6 +274,7 @@ EXC( LOAD t2, UNIT(2)(src), l_exc_copy) EXC( LOAD t3, UNIT(3)(src), l_exc_copy) SUB len, len, 4*NBYTES ADD src, src, 4*NBYTES + R10KCBARRIER(0(ra)) EXC( STORE t0, UNIT(0)(dst), s_exc_p4u) EXC( STORE t1, UNIT(1)(dst), s_exc_p3u) EXC( STORE t2, UNIT(2)(dst), s_exc_p2u) @@ -287,6 +290,7 @@ less_than_4units: beq rem, len, copy_bytes nop 1: + R10KCBARRIER(0(ra)) EXC( LOAD t0, 0(src), l_exc) ADD src, src, NBYTES SUB len, len, NBYTES @@ -334,6 +338,7 @@ EXC( LDFIRST t3, FIRST(0)(src), l_exc) EXC( LDREST t3, REST(0)(src), l_exc_copy) SUB t2, t2, t1 # t2 = number of bytes copied xor match, t0, t1 + R10KCBARRIER(0(ra)) EXC( STFIRST t3, FIRST(0)(dst), s_exc) beq len, t2, done SUB len, len, t2 @@ -354,6 +359,7 @@ src_unaligned_dst_aligned: * It's OK to load FIRST(N+1) before REST(N) because the two addresses * are to the same unit (unless src is aligned, but it's not). */ + R10KCBARRIER(0(ra)) EXC( LDFIRST t0, FIRST(0)(src), l_exc) EXC( LDFIRST t1, FIRST(1)(src), l_exc_copy) SUB len, len, 4*NBYTES @@ -384,6 +390,7 @@ cleanup_src_unaligned: beq rem, len, copy_bytes nop 1: + R10KCBARRIER(0(ra)) EXC( LDFIRST t0, FIRST(0)(src), l_exc) EXC( LDREST t0, REST(0)(src), l_exc_copy) ADD src, src, NBYTES @@ -399,6 +406,7 @@ copy_bytes_checklen: nop copy_bytes: /* 0 < len < NBYTES */ + R10KCBARRIER(0(ra)) #define COPY_BYTE(N) \ EXC( lb t0, N(src), l_exc); \ SUB len, len, 1; \ @@ -528,6 +536,7 @@ LEAF(__rmemcpy) /* a0=dst a1=src a2=len */ ADD a1, a2 # src = src + len r_end_bytes: + R10KCBARRIER(0(ra)) lb t0, -1(a1) SUB a2, a2, 0x1 sb t0, -1(a0) @@ -542,6 +551,7 @@ r_out: move a2, zero r_end_bytes_up: + R10KCBARRIER(0(ra)) lb t0, (a1) SUB a2, a2, 0x1 sb t0, (a0) diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S index 3bf3842234..c018a47216 100644 --- a/arch/mips/lib/memset.S +++ b/arch/mips/lib/memset.S @@ -86,6 +86,7 @@ FEXPORT(__bzero) .set at #endif + R10KCBARRIER(0(ra)) #ifdef __MIPSEB__ EX(LONG_S_L, a1, (a0), first_fixup) /* make word/dword aligned */ #endif @@ -103,11 +104,13 @@ FEXPORT(__bzero) PTR_ADDU t1, a0 /* end address */ .set reorder 1: PTR_ADDIU a0, 64 + R10KCBARRIER(0(ra)) f_fill64 a0, -64, a1, fwd_fixup bne t1, a0, 1b .set noreorder memset_partial: + R10KCBARRIER(0(ra)) PTR_LA t1, 2f /* where to start */ #if LONGSIZE == 4 PTR_SUBU t1, t0 @@ -129,6 +132,7 @@ memset_partial: beqz a2, 1f PTR_ADDU a0, a2 /* What's left */ + R10KCBARRIER(0(ra)) #ifdef __MIPSEB__ EX(LONG_S_R, a1, -1(a0), last_fixup) #endif @@ -143,6 +147,7 @@ small_memset: PTR_ADDU t1, a0, a2 1: PTR_ADDIU a0, 1 /* fill bytewise */ + R10KCBARRIER(0(ra)) bne t1, a0, 1b sb a1, -1(a0) diff --git a/arch/mips/lib/strncpy_user.S b/arch/mips/lib/strncpy_user.S index 5c8fb9d6b7..8a63f72b81 100644 --- a/arch/mips/lib/strncpy_user.S +++ b/arch/mips/lib/strncpy_user.S @@ -38,6 +38,7 @@ FEXPORT(__strncpy_from_user_nocheck_asm) .set noreorder 1: EX(lbu, t0, (v1), fault) PTR_ADDIU v1, 1 + R10KCBARRIER(0(ra)) beqz t0, 2f sb t0, (a0) PTR_ADDIU v0, 1 diff --git a/include/asm-mips/asm.h b/include/asm-mips/asm.h index 12e17581b8..608cfcfbb3 100644 --- a/include/asm-mips/asm.h +++ b/include/asm-mips/asm.h @@ -398,4 +398,12 @@ symbol = value #define SSNOP sll zero, zero, 1 +#ifdef CONFIG_SGI_IP28 +/* Inhibit speculative stores to volatile (e.g.DMA) or invalid addresses. */ +#include +#define R10KCBARRIER(addr) cache Cache_Barrier, addr; +#else +#define R10KCBARRIER(addr) +#endif + #endif /* __ASM_ASM_H */ -- 2.39.5