[coreboot] [patch]: memcpy/memset inline asm & config_compress disabled when needed

[Bao, Zheng]

My fam10 is quite slow when it decompressing the module from rom to ram.
So I have to make some modification. It is not the final resolution. But
both of these two patches have their own meanings. 

disable_compress_asneeded.patch:
Sometimes we need to disable the COMPRESS_FLAG. The default value
is 1 as it was. If we set CONFIG_COMPRESS is 0 in mainboard Kconfig,
we should disable the CBFS_COMPRESS_FLAG.

   Kconfig:
   ------------------
        config COMPRESS
                hex
                default 0
                depends on BOARD_AMD_MAHOGANY_FAM10

Signed-off-by: Zheng Bao <zheng....@amd.com>


Index: Makefile
===================================================================
--- Makefile    (revision 5133)
+++ Makefile    (working copy)
@@ -231,6 +231,9 @@
 CFLAGS += -fno-common -ffreestanding -fno-builtin -fomit-frame-pointer
 
 CBFS_COMPRESS_FLAG:=l
+ifeq ($(CONFIG_COMPRESS),0)
+CBFS_COMPRESS_FLAG:=
+endif
 CBFS_PAYLOAD_COMPRESS_FLAG:=
 ifeq ($(CONFIG_COMPRESSED_PAYLOAD_LZMA),y)
 CBFS_PAYLOAD_COMPRESS_FLAG:=l 


memcpy_memset_inline_asm.patch:
Rewrite the memset/memcpy as inlined asmembly code. It make the code
run much faster if memcpy runs in ROM.

Signed-off-by: Zheng Bao <zheng....@amd.com>

Index: src/lib/memcpy.c
===================================================================
--- src/lib/memcpy.c    (revision 5133)
+++ src/lib/memcpy.c    (working copy)
@@ -3,10 +3,14 @@
 {
        const char *src = vsrc;
        char *dest = vdest;
-       int i;
 
-       for (i = 0; i < (int)bytes; i++)
-               dest[i] = src[i];
+       __asm__ __volatile__ (                          \
+               "cld \n\t"                              \
+               "rep \n\t"                              \
+               "movsb"                                 \
+               :               /* No output */         \
+               : "S"(src), "D"(dest), "c"(bytes)       \
+               );
 
        return vdest;
 }
Index: src/lib/memset.c
===================================================================
--- src/lib/memset.c    (revision 5133)
+++ src/lib/memset.c    (working copy)
@@ -2,11 +2,15 @@
 
 void *memset(void *s, int c, size_t n)
 {
-       int i;
        char *ss = (char *) s;
 
-       for (i = 0; i < (int)n; i++)
-               ss[i] = c;
+       __asm__ __volatile__ (                  \
+               "cld\n\t"                       \
+               "rep\n\t"                       \
+               "stosb"                         \
+               :                               \
+               : "a"(c), "D"(ss), "c"(n)       \
+               );
 
        return s;
 }

memcpy_memset_inline_asm.patch
Description: memcpy_memset_inline_asm.patch

disable_compress_asneeded.patch
Description: disable_compress_asneeded.patch

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