From f3b2b7af08efd9872c973f47410b39de63490230 Mon Sep 17 00:00:00 2001
From: hpa <hpa>
Date: Mon, 18 Nov 2002 19:31:19 +0000
Subject: [PATCH] Fix MEMDISK initalization bugs

---
 NEWS             |  4 ++++
 memdisk/msetup.c | 24 ++++++++++++++----------
 memdisk/setup.c  | 22 ++++++++++++++++++----
 3 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/NEWS b/NEWS
index acaa087..42bd36f 100644
--- a/NEWS
+++ b/NEWS
@@ -3,6 +3,10 @@ apply to that specific program only; other changes apply to all of
 them.
 
 Changes in 2.01:
+	* MEMDISK: Fix memory sizing bug when the ramdisk crosses the
+	  16 MB boundary.
+	* MEMDISK: Add a "pause" option to stop immediately before
+	  booting, to read off the messages.
 	* MEMDISK: Support disk images with DOSEMU headers.
 	* Update the mkdiskimage script to handle newer mtools
 	  versions, and be able to generate disk images with DOSEMU
diff --git a/memdisk/msetup.c b/memdisk/msetup.c
index f9ed071..3c0b1c7 100644
--- a/memdisk/msetup.c
+++ b/memdisk/msetup.c
@@ -131,31 +131,35 @@ void get_mem(void)
   }
 }
 
+#define PW(x) (1ULL << (x))
+
 void parse_mem(void)
 {
   struct e820range *ep;
 
+  dos_mem = low_mem = high_mem = 0;
+
   /* Derive "dos mem", "high mem", and "low mem" from the range array */
   for ( ep = ranges ; ep->type != -1 ; ep++ ) {
     if ( ep->type == 1 ) {
       /* Only look at memory ranges */
       if ( ep->start == 0 ) {
-	if ( ep[1].start > 0x100000 )
-	  dos_mem = 0x100000;
+	if ( ep[1].start > PW(20) )
+	  dos_mem = PW(20);
 	else
 	  dos_mem = ep[1].start;
       }
-      if ( ep->start <= 0x00100000 && ep[1].start > 0x00100000 ) {
-	if ( ep[1].start > 0x01000000 )
-	  low_mem =  0x01000000 - 0x00100000;
+      if ( ep->start <= PW(20) && ep[1].start > PW(20) ) {
+	if ( ep[1].start > PW(24) )
+	  low_mem = PW(24) - PW(20);
 	else
-	  low_mem = ep[1].start - 0x00100000;
+	  low_mem = ep[1].start - PW(20);
       }
-      if ( ep->start <= 0x01000000 && ep[1].start > 0x01000000 ) {
-	if ( ep[1].start > 0x100000000 )
-	  high_mem = 0x100000000 - 0x01000000;
+      if ( ep->start <= PW(24) && ep[1].start > PW(24) ) {
+	if ( ep[1].start > PW(32) )
+	  high_mem = PW(32) - PW(24);
 	else
-	  high_mem = ep[1].start - 0x01000000;
+	  high_mem = ep[1].start - PW(24);
       }
     }
   }
diff --git a/memdisk/setup.c b/memdisk/setup.c
index b96b431..249d847 100644
--- a/memdisk/setup.c
+++ b/memdisk/setup.c
@@ -572,6 +572,13 @@ uint32_t setup(void)
   insertrange(driveraddr, dos_mem-driveraddr, 2);
   parse_mem();
 
+  printf("dos_mem  = %#10x (%u K)\n"
+	 "low_mem  = %#10x (%u K)\n"
+	 "high_mem = %#10x (%u K)\n",
+	 dos_mem, dos_mem >> 10,
+	 low_mem, low_mem >> 10,
+	 high_mem, high_mem >> 10);
+
   pptr->mem1mb     = low_mem  >> 10;
   pptr->mem16mb    = high_mem >> 16;
   if ( low_mem == (15 << 20) ) {
@@ -582,9 +589,8 @@ uint32_t setup(void)
     pptr->memint1588 = low_mem >> 10;
   }
 
-  printf("mem1mb  = %5u (0x%04x)\n", pptr->mem1mb, pptr->mem1mb);
-  printf("mem16mb = %5u (0x%04x)\n", pptr->mem16mb, pptr->mem16mb);
-  printf("mem1588 = %5u (0x%04x)\n", pptr->memint1588, pptr->memint1588);
+  printf("1588: 0x%04x  15E801: 0x%04x 0x%04x\n",
+	 pptr->memint1588, pptr->mem1mb, pptr->mem16mb);
 
   driverseg = driveraddr >> 4;
   driverptr = driverseg  << 16;
@@ -622,7 +628,7 @@ uint32_t setup(void)
 		 : "esi", "ebx", "ebp");
 
     if ( cf ) {
-      printf("INT 13 08: Failure\n");
+      printf("INT 13 08: Failure, assuming this is the only drive\n");
       pptr->drivecnt = 1;
     } else {
       printf("INT 13 08: Success, count = %u, BPT = %04x:%04x\n",
@@ -705,6 +711,14 @@ uint32_t setup(void)
     die();
   }
   
+  if ( getcmditem("pause") != CMD_NOTFOUND ) {
+    puts("Press any key to boot... ");
+    asm volatile("pushal ; "
+		 "xorw %ax,%ax ; "
+		 "int $0x16 ; "
+		 "popal");
+  }
+
   puts("Booting...\n");
 
   /* On return the assembly code will jump to the boot vector */
-- 
2.7.4