[PATCH]: b157c9bb0e mem_ap: fix GDB connections

[gerrit]

This is an automated email from Gerrit.

"Antonio Borneo <borneo.anto...@gmail.com>" just uploaded a new patch set to 
Gerrit, which you can find at https://review.openocd.org/c/openocd/+/8163

-- gerrit

commit b157c9bb0e2158775f1cc136d5f6494c932dbb57
Author: Antonio Borneo <borneo.anto...@gmail.com>
Date:   Sun Feb 25 12:22:44 2024 +0100

    mem_ap: fix GDB connections
    
    After commit d9b2607ca094 ("gdb_server: support sparse register
    maps"), GDB crashes while requesting the value of 'cpsr' because
    the fake register is tagged as not existing.
    
    Change the logic and set all register as existing, while still
    limiting the list for the initial GDB request at connect.
    
    Change-Id: I1c4e274c06147683db2a59a8920ae5ccd863e15c
    Signed-off-by: Antonio Borneo <borneo.anto...@gmail.com>

diff --git a/src/target/mem_ap.c b/src/target/mem_ap.c
index 5c81e3a75f..61a9475e64 100644
--- a/src/target/mem_ap.c
+++ b/src/target/mem_ap.c
@@ -194,11 +194,11 @@ static const char *mem_ap_get_gdb_arch(const struct 
target *target)
  * reg[24]:     32 bits, fps
  * reg[25]:     32 bits, cpsr
  *
- * Set 'exist' only to reg[0..15], so initial response to GDB is correct
+ * GDB requires only reg[0..15]
  */
 #define NUM_REGS     26
+#define NUM_GDB_REGS 16
 #define MAX_REG_SIZE 96
-#define REG_EXIST(n) ((n) < 16)
 #define REG_SIZE(n)  ((((n) >= 16) && ((n) < 24)) ? 96 : 32)
 
 struct mem_ap_alloc_reg_list {
@@ -218,14 +218,14 @@ static int mem_ap_get_gdb_reg_list(struct target *target, 
struct reg **reg_list[
        }
 
        *reg_list = mem_ap_alloc->reg_list;
-       *reg_list_size = NUM_REGS;
+       *reg_list_size = (reg_class == REG_CLASS_ALL) ? NUM_REGS : NUM_GDB_REGS;
        struct reg *regs = mem_ap_alloc->regs;
 
        for (int i = 0; i < NUM_REGS; i++) {
                regs[i].number = i;
                regs[i].value = mem_ap_alloc->regs_value;
                regs[i].size = REG_SIZE(i);
-               regs[i].exist = REG_EXIST(i);
+               regs[i].exist = true;
                regs[i].type = &mem_ap_reg_arch_type;
                (*reg_list)[i] = &regs[i];
        }

--