target/openrisc: Fixes for memory debugging

When debugging in gdb you might want to inspect instructions in mapped
pages or in exception vectors like 0x800 etc.  This was previously not
possible in qemu since the *get_phys_page_debug() routine only looked
into the data tlb.

Change to fall back to look into instruction tlb and plain physical
pages.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Stafford Horne <shorne@gmail.com>

diff --git a/target/openrisc/mmu.c b/target/openrisc/mmu.c
index 56b11d3d68326e0df086612fca41b42f97bfbfa8..ce2a29dd1a63721b629828fb0dce2d9993e607bd 100644 (file)
--- a/target/openrisc/mmu.c
+++ b/target/openrisc/mmu.c
@@ -124,7 +124,7 @@ static int cpu_openrisc_get_phys_addr(OpenRISCCPU *cpu,
 {
     int ret = TLBRET_MATCH;
 
-    if (rw == 2) {    /* ITLB */
+    if (rw == MMU_INST_FETCH) {    /* ITLB */
        *physical = 0;
         ret = cpu->env.tlb->cpu_openrisc_map_address_code(cpu, physical,
                                                           prot, address, rw);
@@ -221,12 +221,28 @@ hwaddr openrisc_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
     OpenRISCCPU *cpu = OPENRISC_CPU(cs);
     hwaddr phys_addr;
     int prot;
+    int miss;
 
-    if (cpu_openrisc_get_phys_addr(cpu, &phys_addr, &prot, addr, 0)) {
-        return -1;
+    /* Check memory for any kind of address, since during debug the
+       gdb can ask for anything, check data tlb for address */
+    miss = cpu_openrisc_get_phys_addr(cpu, &phys_addr, &prot, addr, 0);
+
+    /* Check instruction tlb */
+    if (miss) {
+        miss = cpu_openrisc_get_phys_addr(cpu, &phys_addr, &prot, addr,
+                                          MMU_INST_FETCH);
+    }
+
+    /* Last, fall back to a plain address */
+    if (miss) {
+        miss = cpu_openrisc_get_phys_nommu(cpu, &phys_addr, &prot, addr, 0);
     }
 
-    return phys_addr;
+    if (miss) {
+        return -1;
+    } else {
+        return phys_addr;
+    }
 }
 
 void cpu_openrisc_mmu_init(OpenRISCCPU *cpu)