armv7m: always set xPSR.T=1 when starting an algorithm

[fw/openocd] / src / target / armv7m.c

diff --git a/src/target/armv7m.c b/src/target/armv7m.c
index 7d3bd73674d554e8aa14fd96991418c687a023e6..a1962fefc8cc12b4248ea32a9c9195346a8dffcb 100644 (file)
--- a/src/target/armv7m.c
+++ b/src/target/armv7m.c
@@ -407,6 +407,23 @@ int armv7m_start_algorithm(struct target *target,
                armv7m_set_core_reg(reg, reg_params[i].value);
        }
 
+       {
+               /*
+                * Ensure xPSR.T is set to avoid trying to run things in arm
+                * (non-thumb) mode, which armv7m does not support.
+                *
+                * We do this by setting the entirety of xPSR, which should
+                * remove all the unknowns about xPSR state.
+                *
+                * Because xPSR.T is populated on reset from the vector table,
+                * it might be 0 if the vector table has "bad" data in it.
+                */
+               struct reg *reg = &armv7m->arm.core_cache->reg_list[ARMV7M_xPSR];
+               buf_set_u32(reg->value, 0, 32, 0x01000000);
+               reg->valid = 1;
+               reg->dirty = 1;
+       }
+
        if (armv7m_algorithm_info->core_mode != ARM_MODE_ANY &&
                        armv7m_algorithm_info->core_mode != core_mode) {