svn commit: r214648 - head/sys/arm/arm

[Olivier Houchard]

Author: cognet
Date: Mon Nov  1 21:04:23 2010
New Revision: 214648
URL: http://svn.freebsd.org/changeset/base/214648

Log:
  Try to be a little smart at guessing where _start is located in flash, instead
  of relying on a binutils bug.
  
  Reported by:	dim

Modified:
  head/sys/arm/arm/elf_trampoline.c

Modified: head/sys/arm/arm/elf_trampoline.c
==============================================================================
--- head/sys/arm/arm/elf_trampoline.c	Mon Nov  1 20:20:31 2010	(r214647)
+++ head/sys/arm/arm/elf_trampoline.c	Mon Nov  1 21:04:23 2010	(r214648)
@@ -159,7 +159,7 @@ _startC(void)
 #if defined(FLASHADDR) && defined(LOADERRAMADDR)
 	unsigned int pc;
 
-	__asm __volatile("adr %0, _start\n"
+	__asm __volatile("mov %0, pc\n"
 	    : "=r" (pc));
 	if ((FLASHADDR > LOADERRAMADDR && pc >= FLASHADDR) ||
 	    (FLASHADDR < LOADERRAMADDR && pc < LOADERRAMADDR)) {
@@ -173,11 +173,13 @@ _startC(void)
 		 */
 		unsigned int target_addr;
 		unsigned int tmp_sp;
+		uint32_t src_addr = (uint32_t)&_start - PHYSADDR + FLASHADDR
+		    + (pc - FLASHADDR - ((uint32_t)&_startC - PHYSADDR)) & 0xfffff000;
 
 		target_addr = (unsigned int)&_start - PHYSADDR + LOADERRAMADDR;
 		tmp_sp = target_addr + 0x100000 +
 		    (unsigned int)&_end - (unsigned int)&_start;
-		memcpy((char *)target_addr, (char *)pc,
+		memcpy((char *)target_addr, (char *)src_addr,
 		    (unsigned int)&_end - (unsigned int)&_start);
 		/* Temporary set the sp and jump to the new location. */
 		__asm __volatile(