target: add target->type->has_mmu fn.

improve default target->read/write_phys_memory, produce
more sensible error messages if the mmu interface
functions have not been implemented yet vs. will
not be implemented(e.g. cortex m3).

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/target/target_type.h b/src/target/target_type.h
index dd469db1..23ed40e0 100644
--- a/src/target/target_type.h
+++ b/src/target/target_type.h
@@ -199,8 +199,16 @@ struct target_type_s
 	 */
 	int (*write_phys_memory)(struct target_s *target, uint32_t phys_address, uint32_t size, uint32_t count, uint8_t *buffer);
 
+	/* returns true if the mmu is enabled. Default implementation returns error. */
 	int (*mmu)(struct target_s *target, int *enabled);
 
+	/* returns true if the target has an mmu. This can only be
+	determined after the target has been examined.
+	
+	Default implementation returns success and has_mmu==true.
+	*/
+	int (*has_mmu)(struct target_s *target, bool *has_mmu);
+
 	/* Read coprocessor - arm specific. Default implementation returns error. */
 	int (*mrc)(struct target_s *target, int cpnum, uint32_t op1, uint32_t op2, uint32_t CRn, uint32_t CRm, uint32_t *value);