Update relocate() to work with get_memmap().

Change semantics; relocate() now just finds a suitable location; it
doesn't actually perform the relocation itself.  Code in libprefix does
the copy in flat real mode.

src/arch/i386/core/relocate.c

@@ -1,6 +1,6 @@
-#include <virtaddr.h>
+#include <io.h>
 #include <registers.h>
-#include <memsizes.h>
+#include <memmap.h>
 
 /*
  * Originally by Eric Biederman
@@ -35,14 +35,27 @@ extern char _end[];
  * @v ix86		x86 register dump from prefix
  * @ret ix86		x86 registers to return to prefix
  *
- * This copies Etherboot to a suitable location near the top of 32-bit
+ * This finds a suitable location for Etherboot near the top of 32-bit
  * address space, and returns the physical address of the new location
  * to the prefix in %edi.
  */
 void relocate ( struct i386_all_regs *ix86 ) {
-	unsigned long addr, eaddr, size;
+	struct memory_map memmap;
+	unsigned long start, end, size, padded_size;
+	unsigned long new_start, new_end;
 	unsigned i;
 
+	/* Get memory map and current location */
+	get_memmap ( &memmap );
+	start = virt_to_phys ( _text );
+	end = virt_to_phys ( _end );
+	size = ( end - start );
+	padded_size = ( size + max_align - 1 );
+
+	DBG ( "Relocate: currently at [%lx,%lx)\n"
+	      "...need %lx bytes for %d-byte alignment\n",
+	      start, end, padded_size, max_align );
+
 	/* Walk through the memory map and find the highest address
 	 * below 4GB that etherboot will fit into.  Ensure etherboot
 	 * lies entirely within a range with A20=0.  This means that
@@ -50,58 +63,29 @@ void relocate ( struct i386_all_regs *ix86 ) {
 	 * etherboot code is still visible and we have a chance to
 	 * diagnose the problem.
 	 */
-
-	/* First find the size of etherboot, including enough space to
-	 * pad it to the required alignment
-	 */
-	size = _end - _text + max_align - 1;
-
-	/* Current end address of Etherboot.  If the current etherboot
-	 * is beyond MAX_ADDR pretend it is at the lowest possible
-	 * address.
-	 */
-	eaddr = virt_to_phys(_end);
-	if ( eaddr > MAX_ADDR ) {
-		eaddr = 0;
-	}
-
-	DBG ( "Relocate: currently at [%x,%x)\n"
-	      "...need %x bytes for %d-byte alignment\n",
-	      virt_to_phys ( _text ), eaddr, size, max_align );
-
-	for ( i = 0; i < meminfo.map_count; i++ ) {
+	new_end = end;
+	for ( i = 0 ; i < memmap.count ; i++ ) {
+		struct memory_region *region = &memmap.regions[i];
 		unsigned long r_start, r_end;
 
-		DBG ( "Considering [%x%x,%x%x)\n",
-		      ( unsigned long ) ( meminfo.map[i].addr >> 32 ),
-		      ( unsigned long ) meminfo.map[i].addr,
-		      ( unsigned long )
-		       ( ( meminfo.map[i].addr + meminfo.map[i].size ) >> 32 ),
-		      ( unsigned long )
-		       ( meminfo.map[i].addr + meminfo.map[i].size ) );
+		DBG ( "Considering [%llx,%llx)\n", region->start, region->end);
 		
-		/* Check block is usable memory */
-		if (meminfo.map[i].type != E820_RAM) {
-			DBG ( "...not RAM\n" );
-			continue;
-		}
-
 		/* Truncate block to MAX_ADDR.  This will be less than
 		 * 4GB, which means that we can get away with using
 		 * just 32-bit arithmetic after this stage.
 		 */
-		if ( meminfo.map[i].addr > MAX_ADDR ) {
-			DBG ( "...starts after MAX_ADDR=%x\n", MAX_ADDR );
+		if ( region->start > MAX_ADDR ) {
+			DBG ( "...starts after MAX_ADDR=%lx\n", MAX_ADDR );
 			continue;
 		}
-		r_start = meminfo.map[i].addr;
-		if ( meminfo.map[i].addr + meminfo.map[i].size > MAX_ADDR ) {
+		r_start = region->start;
+		if ( region->end > MAX_ADDR ) {
+			DBG ( "...end truncated to MAX_ADDR=%lx\n", MAX_ADDR );
 			r_end = MAX_ADDR;
-			DBG ( "...end truncated to MAX_ADDR=%x\n", MAX_ADDR );
 		} else {
-			r_end = meminfo.map[i].addr + meminfo.map[i].size;
+			r_end = region->end;
 		}
-
+		
 		/* Shrink the range down to use only even megabytes
 		 * (i.e. A20=0).
 		 */
@@ -111,7 +95,7 @@ void relocate ( struct i386_all_regs *ix86 ) {
 			 * the top of the next even megabyte.
 			 */
 			r_end = ( r_end - 1 ) & ~0xfffff;
-			DBG ( "...end truncated to %x "
+			DBG ( "...end truncated to %lx "
 			      "(avoid ending in odd megabyte)\n",
 			      r_end );
 		} else if ( ( r_end - size ) & 0x100000 ) {
@@ -126,13 +110,13 @@ void relocate ( struct i386_all_regs *ix86 ) {
 			 */
 			if ( r_end > 0x100000 ) {
 				r_end = ( r_end - 0x100000 ) & ~0xfffff;
-				DBG ( "...end truncated to %x "
+				DBG ( "...end truncated to %lx "
 				      "(avoid starting in odd megabyte)\n",
 				      r_end );
 			}
 		}
 
-		DBG ( "...usable portion is [%x,%x)\n", r_start, r_end );
+		DBG ( "...usable portion is [%lx,%lx)\n", r_start, r_end );
 
 		/* If we have rounded down r_end below r_ start, skip
 		 * this block.
@@ -143,8 +127,8 @@ void relocate ( struct i386_all_regs *ix86 ) {
 		}
 
 		/* Check that there is enough space to fit in Etherboot */
-		if ( r_end - r_start < size ) {
-			DBG ( "...too small (need %x bytes)\n", size );
+		if ( ( r_end - r_start ) < size ) {
+			DBG ( "...too small (need %lx bytes)\n", size );
 			continue;
 		}
 
@@ -156,30 +140,24 @@ void relocate ( struct i386_all_regs *ix86 ) {
 		 * Etherboot, as well as choosing the highest of all
 		 * viable blocks.
 		 */
-		if ( r_end - size > eaddr ) {
-			eaddr = r_end;
+		if ( ( r_end - size ) > new_end ) {
+			new_end = r_end;
 			DBG ( "...new best block found.\n" );
 		}
 	}
 
-	DBG ( "New location will be in [%x,%x)\n", eaddr - size, eaddr );
-
 	/* Calculate new location of Etherboot, and align it to the
 	 * required alignemnt.
 	 */
-	addr = eaddr - size;
-	addr += ( virt_to_phys ( _text ) - addr ) & ( max_align - 1 );
-	DBG ( "After alignment, new location is [%x,%x)\n",
-	      addr, addr + _end - _text );
+	new_start = new_end - padded_size;
+	new_start += ( start - new_start ) & ( max_align - 1 );
+	new_end = new_start + size;
 
-	if ( addr != virt_to_phys ( _text ) ) {
-		DBG ( "Relocating _text from: [%lx,%lx) to [%lx,%lx)\n",
-		      virt_to_phys ( _text ), virt_to_phys ( _end ),
-		      addr, addr + _end - _text );
-
-		memcpy ( phys_to_virt ( addr ), _text, _end - _text );
-	}
+	DBG ( "Relocating from [%lx,%lx) to [%lx,%lx)\n",
+	      start, end, new_start, new_end );
 	
-	/* Let prefix know where the new copy is */
-	ix86->regs.edi = addr;
+	/* Let prefix know what to copy */
+	ix86->regs.esi = start;
+	ix86->regs.edi = new_start;
+	ix86->regs.ecx = size;
 }