boot-83.2.tar.gz

[apple/boot.git] / i386 / libsaio / biosfn.c

diff --git a/i386/libsaio/biosfn.c b/i386/libsaio/biosfn.c
index 41b11d7454c7b643bdb5b9cadb70fe99962457c6..ff0d3a3950b55b6a611fa62c994932379cb30f35 100644 (file)
--- a/i386/libsaio/biosfn.c
+++ b/i386/libsaio/biosfn.c
@@ -81,16 +81,29 @@ unsigned int time18(void)
 
 int memsize(int which)
 {
-    if (which) {
-        get_memsize(&bb);              
-               return (bb.edx.rr << 16) | bb.eax.rr;
+    int size;
+        
+    if ( which )
+    {
+        // Get the total system memory discovered by the
+        // BIOS in kilobytes.
+
+        get_memsize(&bb);
+        size = (bb.edx.rr << 16) | bb.eax.rr;
+
+        // Convert to extended memory size.
+
+        size = ( size > 1024 ) ? size - 1024 : 0;
     }
-    else {
-        /* conventional memory */
+    else
+    {
+        // Get amount of conventional memory available.
+
         bb.intno = 0x12;
         bios(&bb);
-        return bb.eax.rr;
+        size = bb.eax.rr;
     }
+    return size;
 }
 
 void video_mode(int mode)
@@ -298,9 +311,9 @@ APMPresent(void)
        (bb.ebx.r.h == 'P') &&
        (bb.ebx.r.l == 'M')) {
            /* Success */
-           kbp->apm_config.major_vers = bb.eax.r.h;
-           kbp->apm_config.minor_vers = bb.eax.r.l;
-           kbp->apm_config.flags.data = bb.ecx.rr;
+           kbp->apmConfig.major_vers = bb.eax.r.h;
+           kbp->apmConfig.minor_vers = bb.eax.r.l;
+           kbp->apmConfig.flags.data = bb.ecx.rr;
            return 1;
     }
     return 0;
@@ -318,19 +331,19 @@ APMConnect32(void)
     bios(&bb);
     if (bb.flags.cf == 0) {
        /* Success */
-       kbp->apm_config.cs32_base = (bb.eax.rr) << 4;
-       kbp->apm_config.entry_offset = bb.ebx.rx;
-       kbp->apm_config.cs16_base = (bb.ecx.rr) << 4;
-       kbp->apm_config.ds_base = (bb.edx.rr) << 4;
-       if (kbp->apm_config.major_vers >= 1 &&
-           kbp->apm_config.minor_vers >= 1) {
-               kbp->apm_config.cs_length = bb.esi.rr;
-               kbp->apm_config.ds_length = bb.edi.rr;
+       kbp->apmConfig.cs32_base = (bb.eax.rr) << 4;
+       kbp->apmConfig.entry_offset = bb.ebx.rx;
+       kbp->apmConfig.cs16_base = (bb.ecx.rr) << 4;
+       kbp->apmConfig.ds_base = (bb.edx.rr) << 4;
+       if (kbp->apmConfig.major_vers >= 1 &&
+           kbp->apmConfig.minor_vers >= 1) {
+               kbp->apmConfig.cs_length = bb.esi.rr;
+               kbp->apmConfig.ds_length = bb.edi.rr;
        } else {
-               kbp->apm_config.cs_length = 
-                   kbp->apm_config.ds_length = 64 * 1024;
+               kbp->apmConfig.cs_length = 
+                   kbp->apmConfig.ds_length = 64 * 1024;
        }
-       kbp->apm_config.connected = 1;
+       kbp->apmConfig.connected = 1;
        return 1;
     }
     return 0;