'fix' buserror assert

emu.c

@@ -185,9 +185,11 @@ static int check_can_access(mem_range_t *m, unsigned int address) {
 static unsigned int read_memory_32(unsigned int address) {
  if (address==0) EMU_LOG_DEBUG("read addr 0\n");
  mem_range_t *m=find_range_by_addr(address);
- //HACK! If this is set, diags get more verbose
-// if (address==0xC00644) return 1; //output 'expected' diag lines
-// if (address==0xC006de) return 1; //output PC of next subtest
+ //HACK! If this is enabled, diags get more verbose
+#if 0
+ if (address==0xC00644) return 1; //output 'expected' diag lines
+ if (address==0xC006de) return 1; //output PC of next subtest
+#endif
  if (!m) {
  EMU_LOG_INFO("Read32 from unmapped addr %08X\n", address);
  dump_cpu_state();
@@ -317,11 +319,9 @@ static int check_mem_access(unsigned int address, int flags) {
  dump_callstack();
  csr_set_access_error(csr, cur_cpu, access);
 
- assert(recursive_error==0);
- recursive_error=1;
+ //note THIS WILL NOT RETURN!
+ //(m68ki_exception_bus_error ends with a longjmp)
  m68k_pulse_bus_error();
- recursive_error=0;
-
  return 0;
  }
  return 1;

mapper.c

@@ -59,6 +59,7 @@ void mapper_set_mapid(mapper_t *m, uint8_t id) {
  m->cur_id=id;
 }
 
+//returns fault indicator, or 0 if allowed
 static int access_allowed_page(mapper_t *m, unsigned int page, int access_flags) {
  assert(page<4096);
  unsigned int ac=(m->desc[page].w1<<16)+m->desc[page].w0;
@@ -82,14 +83,15 @@ int mapper_access_allowed(mapper_t *m, unsigned int a, int access_flags) {
  if (a>=0x800000) {
  //Anything except RAM does not go through the mapper, but is only
  //accessible in system mode.
- return (access_flags&ACCESS_SYSTEM)?ACCESS_ERROR_OK:ACCESS_ERROR_A;
+ int ret=(access_flags&ACCESS_SYSTEM)?ACCESS_ERROR_OK:ACCESS_ERROR_A;
+ if (ret==ACCESS_ERROR_A) {
+ MAPPER_LOG_INFO("mapper_access_allowed: address %x not accessible in user mode\n", a);
+ }
+ return ret;
  }
  //Map virtual page to phyical page.
  int p=a>>12; //4K pages
- if (p>=2048) {
- MAPPER_LOG_INFO("mapper_access_allowed: out of range addr %x\n", a);
- exit(1);
- }
+ assert(p<=2048 && "out of range addr");
  if (access_flags&ACCESS_SYSTEM) p+=2048;
  int r=access_allowed_page(m, p, access_flags);
  if (r) {