[PATCH]: 88335da9c target/cortex_m: add address helpers

[gerrit]

This is an automated email from Gerrit.

"Tomas Vanek <van...@fbl.cz>" just uploaded a new patch set to Gerrit, which 
you can find at https://review.openocd.org/c/openocd/+/6772

-- gerrit

commit 88335da9cc9ec917f5d54a53bfdb6f8b40653402
Author: Tomas Vanek <van...@fbl.cz>
Date:   Fri Dec 10 17:27:54 2021 +0100

    target/cortex_m: add address helpers
    
    cortex_m_is_execute_never() checks for XN areas.
    cortex_m_is_magic() checks for magic address used for exception return or 
lockup.
    
    Change-Id: I1dbcfc06aeb63b0c3bd6df6a94965f60d4fe4466
    Signed-off-by: Tomas Vanek <van...@fbl.cz>

diff --git a/src/target/cortex_m.h b/src/target/cortex_m.h
index c2f836a35..426c473a0 100644
--- a/src/target/cortex_m.h
+++ b/src/target/cortex_m.h
@@ -267,6 +267,36 @@ static inline bool is_cortex_m_with_dap_access(const 
struct cortex_m_common *cor
        return !cortex_m->armv7m.is_hla_target;
 }
 
+/** Check for XN (execute never) address
+ * ARMv7-M Architecture Reference Manual B3.1 The system address map
+ * Armv8-M Architecture Reference Manual B8.1 System address map
+ */
+static inline bool cortex_m_is_execute_never(uint32_t address)
+{
+       /* Peripheral */
+       if ((address & 0xe0000000) == 0x40000000)
+               return true;
+       if (address > 0xa0000000)
+               return true;
+       return false;
+}
+
+/** Check for magic PC/LR values used for exception return or lockup
+ * ARMv7-M Architecture Reference Manual B1.5.8 Exception return behavior
+ * Armv8-M Architecture Reference Manual
+ *  D1.2.95 EXC_RETURN, Exception Return Payload
+ *  B3.33 Lockup
+ */
+static inline bool cortex_m_is_magic(uint32_t address)
+{
+       /* Detect only actually used EXC_RETURN space, not reserved area */
+       if ((address & 0xffffff80) == 0xffffff80)
+               return true;
+       if (address == 0xeffffffe)
+               return true;
+       return false;
+}
+
 int cortex_m_examine(struct target *target);
 int cortex_m_set_breakpoint(struct target *target, struct breakpoint 
*breakpoint);
 int cortex_m_unset_breakpoint(struct target *target, struct breakpoint 
*breakpoint);

--