ARM: only use one set of dummy FPA registers

All ARM cores need to provide obsolete FPA registers in their
GDB register dumps.  (Even though cores with floating point
support now generally use some version of VFP...)

Clean up that support a bit by sharing the same dummy registers,
and removing the duplicate copies.  Eventually we shouldn't need
to export those dummies.

(This makes the ARMv7-M support include the armv4_5 header, and
cleans up related #includes, but doesn't yet use anything from
there except those dummies.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

1 files changed, 28 insertions, 17 deletions

diff --git a/src/target/armv4_5.c b/src/target/armv4_5.c
index 6f8d14cd..aba44319 100644
--- a/src/target/armv4_5.c
+++ b/src/target/armv4_5.c
@@ -189,30 +189,44 @@ int armv4_5_core_reg_map[7][17] =
 	}
 };
 
-uint8_t armv4_5_gdb_dummy_fp_value[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+static const uint8_t arm_gdb_dummy_fp_value[12];
 
-struct reg armv4_5_gdb_dummy_fp_reg =
+/**
+ * Dummy FPA registers are required to support GDB on ARM.
+ * Register packets require eight obsolete FPA register values.
+ * Modern ARM cores use Vector Floating Point (VFP), if they
+ * have any floating point support.  VFP is not FPA-compatible.
+ */
+struct reg arm_gdb_dummy_fp_reg =
 {
-	.name = "GDB dummy floating-point register",
-	.value = armv4_5_gdb_dummy_fp_value,
-	.dirty = 0,
+	.name = "GDB dummy FPA register",
+	.value = (uint8_t *) arm_gdb_dummy_fp_value,
 	.valid = 1,
 	.size = 96,
-	.arch_info = NULL,
 };
 
-uint8_t armv4_5_gdb_dummy_fps_value[] = {0, 0, 0, 0};
+static const uint8_t arm_gdb_dummy_fps_value[4];
 
-struct reg armv4_5_gdb_dummy_fps_reg =
+/**
+ * Dummy FPA status registers are required to support GDB on ARM.
+ * Register packets require an obsolete FPA status register.
+ */
+struct reg arm_gdb_dummy_fps_reg =
 {
-	.name = "GDB dummy floating-point status register",
-	.value = armv4_5_gdb_dummy_fps_value,
-	.dirty = 0,
+	.name = "GDB dummy FPA status register",
+	.value = (uint8_t *) arm_gdb_dummy_fps_value,
 	.valid = 1,
 	.size = 32,
-	.arch_info = NULL,
 };
 
+static void arm_gdb_dummy_init(void) __attribute__ ((constructor));
+
+static void arm_gdb_dummy_init(void)
+{
+	register_init_dummy(&arm_gdb_dummy_fp_reg);
+	register_init_dummy(&arm_gdb_dummy_fps_reg);
+}
+
 int armv4_5_get_core_reg(struct reg *reg)
 {
 	int retval;
@@ -313,9 +327,6 @@ struct reg_cache* armv4_5_build_reg_cache(struct target *target, struct arm *arm
 	cache->reg_list = reg_list;
 	cache->num_regs = num_regs;
 
-	register_init_dummy(&armv4_5_gdb_dummy_fp_reg);
-	register_init_dummy(&armv4_5_gdb_dummy_fps_reg);
-
 	for (i = 0; i < 37; i++)
 	{
 		arch_info[i] = armv4_5_core_reg_list_arch_info[i];
@@ -550,10 +561,10 @@ int armv4_5_get_gdb_reg_list(struct target *target, struct reg **reg_list[], int
 
 	for (i = 16; i < 24; i++)
 	{
-		(*reg_list)[i] = &armv4_5_gdb_dummy_fp_reg;
+		(*reg_list)[i] = &arm_gdb_dummy_fp_reg;
 	}
 
-	(*reg_list)[24] = &armv4_5_gdb_dummy_fps_reg;
+	(*reg_list)[24] = &arm_gdb_dummy_fps_reg;
 	(*reg_list)[25] = &armv4_5->core_cache->reg_list[ARMV4_5_CPSR];
 
 	return ERROR_OK;