MIPS: dsp: Add assembler support for DSP ASEs.

Newer toolchains support the DSP and DSP Rev2 instructions. This patch
performs a check for that support and adds compiler and assembler
flags for only the files that need use those instructions.

Signed-off-by: Steven J. Hill <sjhill@mips.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/4752/
Signed-off-by: John Crispin <blogic@openwrt.org>

diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 3e36745670b29629be437fb864fe70f395551d70..578132219ff6ef3ad95b3dc21b4ee126f971aef8 100644 (file)
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -1155,36 +1155,26 @@ do {                                                                    \
         : "=r" (__res));                                        \
         __res;})
 
+#ifdef HAVE_AS_DSP
 #define rddsp(mask)                                                    \
 ({                                                                     \
-       unsigned int __res;                                             \
+       unsigned int __dspctl;                                          \
                                                                        \
        __asm__ __volatile__(                                           \
-       "       .set    push                            \n"             \
-       "       .set    noat                            \n"             \
-       "       # rddsp $1, %x1                         \n"             \
-       "       .word   0x7c000cb8 | (%x1 << 16)        \n"             \
-       "       move    %0, $1                          \n"             \
-       "       .set    pop                             \n"             \
-       : "=r" (__res)                                                  \
+       "       rddsp   %0, %x1                                 \n"     \
+       : "=r" (__dspctl)                                               \
        : "i" (mask));                                                  \
-       __res;                                                          \
+       __dspctl;                                                       \
 })
 
 #define wrdsp(val, mask)                                               \
 do {                                                                   \
        __asm__ __volatile__(                                           \
-       "       .set    push                                    \n"     \
-       "       .set    noat                                    \n"     \
-       "       move    $1, %0                                  \n"     \
-       "       # wrdsp $1, %x1                                 \n"     \
-       "       .word   0x7c2004f8 | (%x1 << 11)                \n"     \
-       "       .set    pop                                     \n"     \
-        :                                                              \
+       "       wrdsp   %0, %x1                                 \n"     \
+       :                                                               \
        : "r" (val), "i" (mask));                                       \
 } while (0)
 
-#if 0  /* Need DSP ASE capable assembler ... */
 #define mflo0() ({ long mflo0; __asm__("mflo %0, $ac0" : "=r" (mflo0)); mflo0;})
 #define mflo1() ({ long mflo1; __asm__("mflo %0, $ac1" : "=r" (mflo1)); mflo1;})
 #define mflo2() ({ long mflo2; __asm__("mflo %0, $ac2" : "=r" (mflo2)); mflo2;})
@@ -1207,6 +1197,35 @@ do {                                                                     \
 
 #else
 
+#define rddsp(mask)                                                    \
+({                                                                     \
+       unsigned int __res;                                             \
+                                                                       \
+       __asm__ __volatile__(                                           \
+       "       .set    push                            \n"             \
+       "       .set    noat                            \n"             \
+       "       # rddsp $1, %x1                         \n"             \
+       "       .word   0x7c000cb8 | (%x1 << 16)        \n"             \
+       "       move    %0, $1                          \n"             \
+       "       .set    pop                             \n"             \
+       : "=r" (__res)                                                  \
+       : "i" (mask));                                                  \
+       __res;                                                          \
+})
+
+#define wrdsp(val, mask)                                               \
+do {                                                                   \
+       __asm__ __volatile__(                                           \
+       "       .set    push                                    \n"     \
+       "       .set    noat                                    \n"     \
+       "       move    $1, %0                                  \n"     \
+       "       # wrdsp $1, %x1                                 \n"     \
+       "       .word   0x7c2004f8 | (%x1 << 11)                \n"     \
+       "       .set    pop                                     \n"     \
+        :                                                              \
+       : "r" (val), "i" (mask));                                       \
+} while (0)
+
 #define mfhi0()                                                                \
 ({                                                                     \
        unsigned long __treg;                                           \

diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 007c33d737154a20c04a8cc2fa109504d77dc151..6c17e1f3d0eccf2e3df55740867a0c9c1cbbe10b 100644 (file)
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -98,4 +98,35 @@ obj-$(CONFIG_HW_PERF_EVENTS) += perf_event_mipsxx.o
 
 obj-$(CONFIG_JUMP_LABEL)       += jump_label.o
 
+#
+# DSP ASE supported for MIPS32 or MIPS64 Release 2 cores only. It is safe
+# to enable DSP assembler support here even if the MIPS Release 2 CPU we
+# are targetting does not support DSP because all code-paths making use of
+# it properly check that the running CPU *actually does* support these
+# instructions.
+#
+ifeq ($(CONFIG_CPU_MIPSR2), y)
+CFLAGS_DSP                     = -DHAVE_AS_DSP
+
+#
+# Check if assembler supports DSP ASE
+#
+ifeq ($(call cc-option-yn,-mdsp), y)
+CFLAGS_DSP                     += -mdsp
+endif
+
+#
+# Check if assembler supports DSP ASE Rev2
+#
+ifeq ($(call cc-option-yn,-mdspr2), y)
+CFLAGS_DSP                     += -mdspr2
+endif
+
+CFLAGS_signal.o                        = $(CFLAGS_DSP)
+CFLAGS_signal32.o              = $(CFLAGS_DSP)
+CFLAGS_process.o               = $(CFLAGS_DSP)
+CFLAGS_branch.o                        = $(CFLAGS_DSP)
+CFLAGS_ptrace.o                        = $(CFLAGS_DSP)
+endif
+
 CPPFLAGS_vmlinux.lds           := $(KBUILD_CFLAGS)