MIPS: lib: csum_partial: Merge EXC and load/store macros

Each load/store macro always adds an entry to the __ex_table
using the EXC macro. There are cases where a load instruction may
never fail such as when we are sure the load happens in the kernel
address space. Therefore, we merge these the EXC and LOADX/STOREX
macros into a single one. We also expand the argument list in the EXC
macro to make the macro more flexible. The extra 'type' argument is not
used by this commit, but it will be used when EVA support is added to
memcpy.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

diff --git a/arch/mips/lib/csum_partial.S b/arch/mips/lib/csum_partial.S
index 5d73d0d..bff5167 100644 (file)
--- a/arch/mips/lib/csum_partial.S
+++ b/arch/mips/lib/csum_partial.S
@@ -328,20 +328,39 @@ LEAF(csum_partial)
  * These handlers do not need to overwrite any data.
  */
 
-#define EXC(inst_reg,addr,handler)             \
-9:     inst_reg, addr;                         \
+/* Instruction type */
+#define LD_INSN 1
+#define ST_INSN 2
+
+/*
+ * Wrapper to add an entry in the exception table
+ * in case the insn causes a memory exception.
+ * Arguments:
+ * insn    : Load/store instruction
+ * type    : Instruction type
+ * reg     : Register
+ * addr    : Address
+ * handler : Exception handler
+ */
+#define EXC(insn, type, reg, addr, handler)    \
+9:     insn reg, addr;                         \
        .section __ex_table,"a";                \
        PTR     9b, handler;                    \
        .previous
 
+#undef LOAD
+
 #ifdef USE_DOUBLE
 
-#define LOAD   ld
-#define LOADL  ldl
-#define LOADR  ldr
-#define STOREL sdl
-#define STORER sdr
-#define STORE  sd
+#define LOADK  ld /* No exception */
+#define LOAD(reg, addr, handler)       EXC(ld, LD_INSN, reg, addr, handler)
+#define LOADBU(reg, addr, handler)     EXC(lbu, LD_INSN, reg, addr, handler)
+#define LOADL(reg, addr, handler)      EXC(ldl, LD_INSN, reg, addr, handler)
+#define LOADR(reg, addr, handler)      EXC(ldr, LD_INSN, reg, addr, handler)
+#define STOREB(reg, addr, handler)     EXC(sb, ST_INSN, reg, addr, handler)
+#define STOREL(reg, addr, handler)     EXC(sdl, ST_INSN, reg, addr, handler)
+#define STORER(reg, addr, handler)     EXC(sdr, ST_INSN, reg, addr, handler)
+#define STORE(reg, addr, handler)      EXC(sd, ST_INSN, reg, addr, handler)
 #define ADD    daddu
 #define SUB    dsubu
 #define SRL    dsrl
@@ -353,12 +372,15 @@ LEAF(csum_partial)
 
 #else
 
-#define LOAD   lw
-#define LOADL  lwl
-#define LOADR  lwr
-#define STOREL swl
-#define STORER swr
-#define STORE  sw
+#define LOADK  lw /* No exception */
+#define LOAD(reg, addr, handler)       EXC(lw, LD_INSN, reg, addr, handler)
+#define LOADBU(reg, addr, handler)     EXC(lbu, LD_INSN, reg, addr, handler)
+#define LOADL(reg, addr, handler)      EXC(lwl, LD_INSN, reg, addr, handler)
+#define LOADR(reg, addr, handler)      EXC(lwr, LD_INSN, reg, addr, handler)
+#define STOREB(reg, addr, handler)     EXC(sb, ST_INSN, reg, addr, handler)
+#define STOREL(reg, addr, handler)     EXC(swl, ST_INSN, reg, addr, handler)
+#define STORER(reg, addr, handler)     EXC(swr, ST_INSN, reg, addr, handler)
+#define STORE(reg, addr, handler)      EXC(sw, ST_INSN, reg, addr, handler)
 #define ADD    addu
 #define SUB    subu
 #define SRL    srl
@@ -439,31 +461,31 @@ FEXPORT(csum_partial_copy_nocheck)
        SUB     len, 8*NBYTES           # subtract here for bgez loop
        .align  4
 1:
-EXC(   LOAD    t0, UNIT(0)(src),       .Ll_exc)
-EXC(   LOAD    t1, UNIT(1)(src),       .Ll_exc_copy)
-EXC(   LOAD    t2, UNIT(2)(src),       .Ll_exc_copy)
-EXC(   LOAD    t3, UNIT(3)(src),       .Ll_exc_copy)
-EXC(   LOAD    t4, UNIT(4)(src),       .Ll_exc_copy)
-EXC(   LOAD    t5, UNIT(5)(src),       .Ll_exc_copy)
-EXC(   LOAD    t6, UNIT(6)(src),       .Ll_exc_copy)
-EXC(   LOAD    t7, UNIT(7)(src),       .Ll_exc_copy)
+       LOAD(t0, UNIT(0)(src), .Ll_exc)
+       LOAD(t1, UNIT(1)(src), .Ll_exc_copy)
+       LOAD(t2, UNIT(2)(src), .Ll_exc_copy)
+       LOAD(t3, UNIT(3)(src), .Ll_exc_copy)
+       LOAD(t4, UNIT(4)(src), .Ll_exc_copy)
+       LOAD(t5, UNIT(5)(src), .Ll_exc_copy)
+       LOAD(t6, UNIT(6)(src), .Ll_exc_copy)
+       LOAD(t7, UNIT(7)(src), .Ll_exc_copy)
        SUB     len, len, 8*NBYTES
        ADD     src, src, 8*NBYTES
-EXC(   STORE   t0, UNIT(0)(dst),       .Ls_exc)
+       STORE(t0, UNIT(0)(dst), .Ls_exc)
        ADDC(sum, t0)
-EXC(   STORE   t1, UNIT(1)(dst),       .Ls_exc)
+       STORE(t1, UNIT(1)(dst), .Ls_exc)
        ADDC(sum, t1)
-EXC(   STORE   t2, UNIT(2)(dst),       .Ls_exc)
+       STORE(t2, UNIT(2)(dst), .Ls_exc)
        ADDC(sum, t2)
-EXC(   STORE   t3, UNIT(3)(dst),       .Ls_exc)
+       STORE(t3, UNIT(3)(dst), .Ls_exc)
        ADDC(sum, t3)
-EXC(   STORE   t4, UNIT(4)(dst),       .Ls_exc)
+       STORE(t4, UNIT(4)(dst), .Ls_exc)
        ADDC(sum, t4)
-EXC(   STORE   t5, UNIT(5)(dst),       .Ls_exc)
+       STORE(t5, UNIT(5)(dst), .Ls_exc)
        ADDC(sum, t5)
-EXC(   STORE   t6, UNIT(6)(dst),       .Ls_exc)
+       STORE(t6, UNIT(6)(dst), .Ls_exc)
        ADDC(sum, t6)
-EXC(   STORE   t7, UNIT(7)(dst),       .Ls_exc)
+       STORE(t7, UNIT(7)(dst), .Ls_exc)
        ADDC(sum, t7)
        .set    reorder                         /* DADDI_WAR */
        ADD     dst, dst, 8*NBYTES
@@ -483,19 +505,19 @@ EXC(      STORE   t7, UNIT(7)(dst),       .Ls_exc)
        /*
         * len >= 4*NBYTES
         */
-EXC(   LOAD    t0, UNIT(0)(src),       .Ll_exc)
-EXC(   LOAD    t1, UNIT(1)(src),       .Ll_exc_copy)
-EXC(   LOAD    t2, UNIT(2)(src),       .Ll_exc_copy)
-EXC(   LOAD    t3, UNIT(3)(src),       .Ll_exc_copy)
+       LOAD(t0, UNIT(0)(src), .Ll_exc)
+       LOAD(t1, UNIT(1)(src), .Ll_exc_copy)
+       LOAD(t2, UNIT(2)(src), .Ll_exc_copy)
+       LOAD(t3, UNIT(3)(src), .Ll_exc_copy)
        SUB     len, len, 4*NBYTES
        ADD     src, src, 4*NBYTES
-EXC(   STORE   t0, UNIT(0)(dst),       .Ls_exc)
+       STORE(t0, UNIT(0)(dst), .Ls_exc)
        ADDC(sum, t0)
-EXC(   STORE   t1, UNIT(1)(dst),       .Ls_exc)
+       STORE(t1, UNIT(1)(dst), .Ls_exc)
        ADDC(sum, t1)
-EXC(   STORE   t2, UNIT(2)(dst),       .Ls_exc)
+       STORE(t2, UNIT(2)(dst), .Ls_exc)
        ADDC(sum, t2)
-EXC(   STORE   t3, UNIT(3)(dst),       .Ls_exc)
+       STORE(t3, UNIT(3)(dst), .Ls_exc)
        ADDC(sum, t3)
        .set    reorder                         /* DADDI_WAR */
        ADD     dst, dst, 4*NBYTES
@@ -508,10 +530,10 @@ EXC(      STORE   t3, UNIT(3)(dst),       .Ls_exc)
        beq     rem, len, .Lcopy_bytes
         nop
 1:
-EXC(   LOAD    t0, 0(src),             .Ll_exc)
+       LOAD(t0, 0(src), .Ll_exc)
        ADD     src, src, NBYTES
        SUB     len, len, NBYTES
-EXC(   STORE   t0, 0(dst),             .Ls_exc)
+       STORE(t0, 0(dst), .Ls_exc)
        ADDC(sum, t0)
        .set    reorder                         /* DADDI_WAR */
        ADD     dst, dst, NBYTES
@@ -534,10 +556,10 @@ EXC(      STORE   t0, 0(dst),             .Ls_exc)
         ADD    t1, dst, len    # t1 is just past last byte of dst
        li      bits, 8*NBYTES
        SLL     rem, len, 3     # rem = number of bits to keep
-EXC(   LOAD    t0, 0(src),             .Ll_exc)
+       LOAD(t0, 0(src), .Ll_exc)
        SUB     bits, bits, rem # bits = number of bits to discard
        SHIFT_DISCARD t0, t0, bits
-EXC(   STREST  t0, -1(t1),             .Ls_exc)
+       STREST(t0, -1(t1), .Ls_exc)
        SHIFT_DISCARD_REVERT t0, t0, bits
        .set reorder
        ADDC(sum, t0)
@@ -554,12 +576,12 @@ EXC(      STREST  t0, -1(t1),             .Ls_exc)
         * Set match = (src and dst have same alignment)
         */
 #define match rem
-EXC(   LDFIRST t3, FIRST(0)(src),      .Ll_exc)
+       LDFIRST(t3, FIRST(0)(src), .Ll_exc)
        ADD     t2, zero, NBYTES
-EXC(   LDREST  t3, REST(0)(src),       .Ll_exc_copy)
+       LDREST(t3, REST(0)(src), .Ll_exc_copy)
        SUB     t2, t2, t1      # t2 = number of bytes copied
        xor     match, t0, t1
-EXC(   STFIRST t3, FIRST(0)(dst),      .Ls_exc)
+       STFIRST(t3, FIRST(0)(dst), .Ls_exc)
        SLL     t4, t1, 3               # t4 = number of bits to discard
        SHIFT_DISCARD t3, t3, t4
        /* no SHIFT_DISCARD_REVERT to handle odd buffer properly */
@@ -581,26 +603,26 @@ EXC(      STFIRST t3, FIRST(0)(dst),      .Ls_exc)
  * 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).
  */
-EXC(   LDFIRST t0, FIRST(0)(src),      .Ll_exc)
-EXC(   LDFIRST t1, FIRST(1)(src),      .Ll_exc_copy)
+       LDFIRST(t0, FIRST(0)(src), .Ll_exc)
+       LDFIRST(t1, FIRST(1)(src), .Ll_exc_copy)
        SUB     len, len, 4*NBYTES
-EXC(   LDREST  t0, REST(0)(src),       .Ll_exc_copy)
-EXC(   LDREST  t1, REST(1)(src),       .Ll_exc_copy)
-EXC(   LDFIRST t2, FIRST(2)(src),      .Ll_exc_copy)
-EXC(   LDFIRST t3, FIRST(3)(src),      .Ll_exc_copy)
-EXC(   LDREST  t2, REST(2)(src),       .Ll_exc_copy)
-EXC(   LDREST  t3, REST(3)(src),       .Ll_exc_copy)
+       LDREST(t0, REST(0)(src), .Ll_exc_copy)
+       LDREST(t1, REST(1)(src), .Ll_exc_copy)
+       LDFIRST(t2, FIRST(2)(src), .Ll_exc_copy)
+       LDFIRST(t3, FIRST(3)(src), .Ll_exc_copy)
+       LDREST(t2, REST(2)(src), .Ll_exc_copy)
+       LDREST(t3, REST(3)(src), .Ll_exc_copy)
        ADD     src, src, 4*NBYTES
 #ifdef CONFIG_CPU_SB1
        nop                             # improves slotting
 #endif
-EXC(   STORE   t0, UNIT(0)(dst),       .Ls_exc)
+       STORE(t0, UNIT(0)(dst), .Ls_exc)
        ADDC(sum, t0)
-EXC(   STORE   t1, UNIT(1)(dst),       .Ls_exc)
+       STORE(t1, UNIT(1)(dst), .Ls_exc)
        ADDC(sum, t1)
-EXC(   STORE   t2, UNIT(2)(dst),       .Ls_exc)
+       STORE(t2, UNIT(2)(dst), .Ls_exc)
        ADDC(sum, t2)
-EXC(   STORE   t3, UNIT(3)(dst),       .Ls_exc)
+       STORE(t3, UNIT(3)(dst), .Ls_exc)
        ADDC(sum, t3)
        .set    reorder                         /* DADDI_WAR */
        ADD     dst, dst, 4*NBYTES
@@ -613,11 +635,11 @@ EXC(      STORE   t3, UNIT(3)(dst),       .Ls_exc)
        beq     rem, len, .Lcopy_bytes
         nop
 1:
-EXC(   LDFIRST t0, FIRST(0)(src),      .Ll_exc)
-EXC(   LDREST  t0, REST(0)(src),       .Ll_exc_copy)
+       LDFIRST(t0, FIRST(0)(src), .Ll_exc)
+       LDREST(t0, REST(0)(src), .Ll_exc_copy)
        ADD     src, src, NBYTES
        SUB     len, len, NBYTES
-EXC(   STORE   t0, 0(dst),             .Ls_exc)
+       STORE(t0, 0(dst), .Ls_exc)
        ADDC(sum, t0)
        .set    reorder                         /* DADDI_WAR */
        ADD     dst, dst, NBYTES
@@ -640,9 +662,9 @@ EXC(        STORE   t0, 0(dst),             .Ls_exc)
        li      t3, SHIFT_START # shift
 /* use .Ll_exc_copy here to return correct sum on fault */
 #define COPY_BYTE(N)                   \
-EXC(   lbu     t0, N(src), .Ll_exc_copy);      \
+       LOADBU(t0, N(src), .Ll_exc_copy);       \
        SUB     len, len, 1;            \
-EXC(   sb      t0, N(dst), .Ls_exc);   \
+       STOREB(t0, N(dst), .Ls_exc);    \
        SLLV    t0, t0, t3;             \
        addu    t3, SHIFT_INC;          \
        beqz    len, .Lcopy_bytes_done; \
@@ -656,9 +678,9 @@ EXC(        sb      t0, N(dst), .Ls_exc);   \
        COPY_BYTE(4)
        COPY_BYTE(5)
 #endif
-EXC(   lbu     t0, NBYTES-2(src), .Ll_exc_copy)
+       LOADBU(t0, NBYTES-2(src), .Ll_exc_copy)
        SUB     len, len, 1
-EXC(   sb      t0, NBYTES-2(dst), .Ls_exc)
+       STOREB(t0, NBYTES-2(dst), .Ls_exc)
        SLLV    t0, t0, t3
        or      t2, t0
 .Lcopy_bytes_done:
@@ -703,11 +725,11 @@ EXC(      sb      t0, NBYTES-2(dst), .Ls_exc)
         *
         * Assumes src < THREAD_BUADDR($28)
         */
-       LOAD    t0, TI_TASK($28)
+       LOADK   t0, TI_TASK($28)
         li     t2, SHIFT_START
-       LOAD    t0, THREAD_BUADDR(t0)
+       LOADK   t0, THREAD_BUADDR(t0)
 1:
-EXC(   lbu     t1, 0(src),     .Ll_exc)
+       LOADBU(t1, 0(src), .Ll_exc)
        ADD     src, src, 1
        sb      t1, 0(dst)      # can't fault -- we're copy_from_user
        SLLV    t1, t1, t2
@@ -718,9 +740,9 @@ EXC(        lbu     t1, 0(src),     .Ll_exc)
        bne     src, t0, 1b
        .set    noreorder
 .Ll_exc:
-       LOAD    t0, TI_TASK($28)
+       LOADK   t0, TI_TASK($28)
         nop
-       LOAD    t0, THREAD_BUADDR(t0)   # t0 is just past last good address
+       LOADK   t0, THREAD_BUADDR(t0)   # t0 is just past last good address
         nop
        SUB     len, AT, t0             # len number of uncopied bytes
        /*