Set carry flag before calling INT 15,e801 and INT 15,e820.

Ignore carry flag for INT 15,88; the Ralf Brown interrupt list says
that CF is unreliable for this call.

diff --git a/src/arch/i386/firmware/pcbios/memmap.c b/src/arch/i386/firmware/pcbios/memmap.c
index 3e508fb..a1e69e0 100644 (file)
--- a/src/arch/i386/firmware/pcbios/memmap.c
+++ b/src/arch/i386/firmware/pcbios/memmap.c
@@ -76,6 +76,7 @@ static unsigned int extmemsize_e801 ( void ) {
        unsigned int extmem;
 
        REAL_EXEC ( rm_mem_e801,
+                   "stc\n\t"
                    "int $0x15\n\t"
                    "pushfw\n\t"
                    "popw %w0\n\t",
@@ -111,10 +112,8 @@ static unsigned int extmemsize_88 ( void ) {
        uint16_t extmem;
 
        REAL_EXEC ( rm_mem_88,
-                   "int $0x15\n\t"
-                   "jnc 1f\n\t"
-                   "xorw %%ax, %%ax\n\t"
-                   "\n1:\n\t",
+                   /* Ignore CF; it is not reliable for this call */
+                   "int $0x15\n\t",
                    1,
                    OUT_CONSTRAINTS ( "=a" ( extmem ) ),
                    IN_CONSTRAINTS ( "a" ( 0x8800 ) ),
@@ -155,6 +154,7 @@ static int meme820 ( struct memory_region *memmap, unsigned int entries ) {
 
        do {
                REAL_EXEC ( rm_mem_e820,
+                           "stc\n\t"
                            "int $0x15\n\t"
                            "pushfw\n\t"
                            "popw %w0\n\t",