MIPS: microMIPS: Disable LL/SC and fix linker bug.

Partially revert commit e0c14a260d66ba35935600d6435940a566fe806b
and turn off LL/SC when building a pure microMIPS kernel. This is
a temporary fix until the cmpxchg assembly macro functions are
re-written to not use the HI/LO registers in address calculations.

Also add .insn in selected user access functions which would
otherwise produce ISA mode jump incompatibilities. This is also a
temporary fix.

Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>

diff --git a/arch/mips/include/asm/mach-sead3/cpu-feature-overrides.h b/arch/mips/include/asm/mach-sead3/cpu-feature-overrides.h
index 193c091..bfbd703 100644 (file)
--- a/arch/mips/include/asm/mach-sead3/cpu-feature-overrides.h
+++ b/arch/mips/include/asm/mach-sead3/cpu-feature-overrides.h
@@ -28,7 +28,11 @@
 /* #define cpu_has_prefetch    ? */
 #define cpu_has_mcheck         1
 /* #define cpu_has_ejtag       ? */
+#ifdef CONFIG_CPU_MICROMIPS
+#define cpu_has_llsc           0
+#else
 #define cpu_has_llsc           1
+#endif
 /* #define cpu_has_vtag_icache ? */
 /* #define cpu_has_dc_aliases  ? */
 /* #define cpu_has_ic_fills_f_dc ? */

diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index bd87e36..1c9edd6 100644 (file)
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -261,6 +261,7 @@ do {                                                                        \
        __asm__ __volatile__(                                           \
        "1:     " insn "        %1, %3                          \n"     \
        "2:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section .fixup,\"ax\"                          \n"     \
        "3:     li      %0, %4                                  \n"     \
        "       j       2b                                      \n"     \
@@ -287,7 +288,9 @@ do {                                                                        \
        __asm__ __volatile__(                                           \
        "1:     lw      %1, (%3)                                \n"     \
        "2:     lw      %D1, 4(%3)                              \n"     \
-       "3:     .section        .fixup,\"ax\"                   \n"     \
+       "3:                                                     \n"     \
+       "       .insn                                           \n"     \
+       "       .section        .fixup,\"ax\"                   \n"     \
        "4:     li      %0, %4                                  \n"     \
        "       move    %1, $0                                  \n"     \
        "       move    %D1, $0                                 \n"     \
@@ -355,6 +358,7 @@ do {                                                                        \
        __asm__ __volatile__(                                           \
        "1:     " insn "        %z2, %3         # __put_user_asm\n"     \
        "2:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section        .fixup,\"ax\"                   \n"     \
        "3:     li      %0, %4                                  \n"     \
        "       j       2b                                      \n"     \
@@ -373,6 +377,7 @@ do {                                                                        \
        "1:     sw      %2, (%3)        # __put_user_asm_ll32   \n"     \
        "2:     sw      %D2, 4(%3)                              \n"     \
        "3:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section        .fixup,\"ax\"                   \n"     \
        "4:     li      %0, %4                                  \n"     \
        "       j       3b                                      \n"     \
@@ -524,6 +529,7 @@ do {                                                                        \
        __asm__ __volatile__(                                           \
        "1:     " insn "        %1, %3                          \n"     \
        "2:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section .fixup,\"ax\"                          \n"     \
        "3:     li      %0, %4                                  \n"     \
        "       j       2b                                      \n"     \
@@ -549,7 +555,9 @@ do {                                                                        \
        "1:     ulw     %1, (%3)                                \n"     \
        "2:     ulw     %D1, 4(%3)                              \n"     \
        "       move    %0, $0                                  \n"     \
-       "3:     .section        .fixup,\"ax\"                   \n"     \
+       "3:                                                     \n"     \
+       "       .insn                                           \n"     \
+       "       .section        .fixup,\"ax\"                   \n"     \
        "4:     li      %0, %4                                  \n"     \
        "       move    %1, $0                                  \n"     \
        "       move    %D1, $0                                 \n"     \
@@ -616,6 +624,7 @@ do {                                                                        \
        __asm__ __volatile__(                                           \
        "1:     " insn "        %z2, %3         # __put_user_unaligned_asm\n" \
        "2:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section        .fixup,\"ax\"                   \n"     \
        "3:     li      %0, %4                                  \n"     \
        "       j       2b                                      \n"     \
@@ -634,6 +643,7 @@ do {                                                                        \
        "1:     sw      %2, (%3)        # __put_user_unaligned_asm_ll32 \n" \
        "2:     sw      %D2, 4(%3)                              \n"     \
        "3:                                                     \n"     \
+       "       .insn                                           \n"     \
        "       .section        .fixup,\"ax\"                   \n"     \
        "4:     li      %0, %4                                  \n"     \
        "       j       3b                                      \n"     \