summaryrefslogtreecommitdiffstats
path: root/hw/mips/mips_jazz.c
diff options
context:
space:
mode:
Diffstat (limited to 'hw/mips/mips_jazz.c')
-rw-r--r--hw/mips/mips_jazz.c47
1 files changed, 33 insertions, 14 deletions
diff --git a/hw/mips/mips_jazz.c b/hw/mips/mips_jazz.c
index 388c15c376..c967b97d80 100644
--- a/hw/mips/mips_jazz.c
+++ b/hw/mips/mips_jazz.c
@@ -111,16 +111,26 @@ static const MemoryRegionOps dma_dummy_ops = {
#define MAGNUM_BIOS_SIZE_MAX 0x7e000
#define MAGNUM_BIOS_SIZE (BIOS_SIZE < MAGNUM_BIOS_SIZE_MAX ? BIOS_SIZE : MAGNUM_BIOS_SIZE_MAX)
-static CPUUnassignedAccess real_do_unassigned_access;
-static void mips_jazz_do_unassigned_access(CPUState *cpu, hwaddr addr,
- bool is_write, bool is_exec,
- int opaque, unsigned size)
+static void (*real_do_transaction_failed)(CPUState *cpu, hwaddr physaddr,
+ vaddr addr, unsigned size,
+ MMUAccessType access_type,
+ int mmu_idx, MemTxAttrs attrs,
+ MemTxResult response,
+ uintptr_t retaddr);
+
+static void mips_jazz_do_transaction_failed(CPUState *cs, hwaddr physaddr,
+ vaddr addr, unsigned size,
+ MMUAccessType access_type,
+ int mmu_idx, MemTxAttrs attrs,
+ MemTxResult response,
+ uintptr_t retaddr)
{
- if (!is_exec) {
+ if (access_type != MMU_INST_FETCH) {
/* ignore invalid access (ie do not raise exception) */
return;
}
- (*real_do_unassigned_access)(cpu, addr, is_write, is_exec, opaque, size);
+ (*real_do_transaction_failed)(cs, physaddr, addr, size, access_type,
+ mmu_idx, attrs, response, retaddr);
}
static void mips_jazz_init(MachineState *machine,
@@ -157,16 +167,25 @@ static void mips_jazz_init(MachineState *machine,
env = &cpu->env;
qemu_register_reset(main_cpu_reset, cpu);
- /* Chipset returns 0 in invalid reads and do not raise data exceptions.
+ /*
+ * Chipset returns 0 in invalid reads and do not raise data exceptions.
* However, we can't simply add a global memory region to catch
- * everything, as memory core directly call unassigned_mem_read/write
- * on some invalid accesses, which call do_unassigned_access on the
- * CPU, which raise an exception.
- * Handle that case by hijacking the do_unassigned_access method on
- * the CPU, and do not raise exceptions for data access. */
+ * everything, as this would make all accesses including instruction
+ * accesses be ignored and not raise exceptions.
+ * So instead we hijack the do_transaction_failed method on the CPU, and
+ * do not raise exceptions for data access.
+ *
+ * NOTE: this behaviour of raising exceptions for bad instruction
+ * fetches but not bad data accesses was added in commit 54e755588cf1e9
+ * to restore behaviour broken by c658b94f6e8c206, but it is not clear
+ * whether the real hardware behaves this way. It is possible that
+ * real hardware ignores bad instruction fetches as well -- if so then
+ * we could replace this hijacking of CPU methods with a simple global
+ * memory region that catches all memory accesses, as we do on Malta.
+ */
cc = CPU_GET_CLASS(cpu);
- real_do_unassigned_access = cc->do_unassigned_access;
- cc->do_unassigned_access = mips_jazz_do_unassigned_access;
+ real_do_transaction_failed = cc->do_transaction_failed;
+ cc->do_transaction_failed = mips_jazz_do_transaction_failed;
/* allocate RAM */
memory_region_allocate_system_memory(ram, NULL, "mips_jazz.ram",