diff mbox series

[v8,85/87] gdbstub: Disable handling of nanoMIPS ISA bit in the MIPS gdbstub

Message ID 1534182832-554-86-git-send-email-aleksandar.markovic@rt-rk.com
State New
Headers show
Series Add nanoMIPS support to QEMU | expand

Commit Message

Aleksandar Markovic Aug. 13, 2018, 5:53 p.m. UTC 
From: James Hogan <james.hogan@mips.com>

nanoMIPS has no ISA bit in the PC, so remove the handling of the low bit
of the PC in the MIPS gdbstub for nanoMIPS. This prevents the PC being
read as e.g. 0xbfc00001, and prevents writing to the PC clearing
MIPS_HFLAG_M16.

Signed-off-by: James Hogan <james.hogan@mips.com>
Signed-off-by: Yongbok Kim <yongbok.kim@mips.com>
Signed-off-by: Aleksandar Markovic <amarkovic@wavecomp.com>
Signed-off-by: Stefan Markovic <smarkovic@wavecomp.com>
---
 target/mips/gdbstub.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/target/mips/gdbstub.c b/target/mips/gdbstub.c
index 18e0e6d..559b69f 100644
--- a/target/mips/gdbstub.c
+++ b/target/mips/gdbstub.c
@@ -60,7 +60,8 @@  int mips_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n)
         return gdb_get_regl(mem_buf, (int32_t)env->CP0_Cause);
     case 37:
         return gdb_get_regl(mem_buf, env->active_tc.PC |
-                                     !!(env->hflags & MIPS_HFLAG_M16));
+                                     (!(env->insn_flags & ISA_NANOMIPS32) &&
+                                      env->hflags & MIPS_HFLAG_M16));
     case 72:
         return gdb_get_regl(mem_buf, 0); /* fp */
     case 89:
@@ -131,10 +132,12 @@  int mips_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n)
         break;
     case 37:
         env->active_tc.PC = tmp & ~(target_ulong)1;
-        if (tmp & 1) {
-            env->hflags |= MIPS_HFLAG_M16;
-        } else {
-            env->hflags &= ~(MIPS_HFLAG_M16);
+        if (!(env->insn_flags & ISA_NANOMIPS32)) {
+            if (tmp & 1) {
+                env->hflags |= MIPS_HFLAG_M16;
+            } else {
+                env->hflags &= ~(MIPS_HFLAG_M16);
+            }
         }
         break;
     case 72: /* fp, ignored */