cortex_m: add detection of MVE feature for Armv8.1-M cores

For Armv8.1-M based cores, detect if the core implements the optional
M-profile vector extension (MVE), using MVFR1 register.

While at there rework armv7m->fp_feature detection based on MVFR0
and MVFR1 registers.

Change-Id: I92d5b1759aea9f7561d285f46acdec51d6efb7b4
Signed-off-by: Tarek BOCHKATI <tarek.bouchkati@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/6950
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins

diff --git a/src/target/armv7m.h b/src/target/armv7m.h
index 8693404d2711ba6aa73489517585666d1616193d..2878dd1c760bde6fa65ce3c3b2bb95f6e45dfc01 100644 (file)
--- a/src/target/armv7m.h
+++ b/src/target/armv7m.h
@@ -211,6 +211,8 @@ enum {
        FPV4_SP,
        FPV5_SP,
        FPV5_DP,
+       FPV5_MVE_I,
+       FPV5_MVE_F,
 };
 
 #define ARMV7M_NUM_CORE_REGS (ARMV7M_CORE_LAST_REG - ARMV7M_CORE_FIRST_REG + 1)

diff --git a/src/target/cortex_m.c b/src/target/cortex_m.c
index d9e8b538f9e83e98c9cd1c7b224745c41d9c59c2..6a29a5fd4c034c94f4a2ce48edcbfe3c958259ee 100644 (file)
--- a/src/target/cortex_m.c
+++ b/src/target/cortex_m.c
@@ -2486,16 +2486,17 @@ static bool cortex_m_has_tz(struct target *target)
        return (dauthstatus & DAUTHSTATUS_SID_MASK) != 0;
 }
 
-#define MVFR0 0xe000ef40
-#define MVFR1 0xe000ef44
 
-#define MVFR0_DEFAULT_M4 0x10110021
-#define MVFR1_DEFAULT_M4 0x11000011
+#define MVFR0          0xE000EF40
+#define MVFR0_SP_MASK  0x000000F0
+#define MVFR0_SP       0x00000020
+#define MVFR0_DP_MASK  0x00000F00
+#define MVFR0_DP       0x00000200
 
-#define MVFR0_DEFAULT_M7_SP 0x10110021
-#define MVFR0_DEFAULT_M7_DP 0x10110221
-#define MVFR1_DEFAULT_M7_SP 0x11000011
-#define MVFR1_DEFAULT_M7_DP 0x12000011
+#define MVFR1          0xE000EF44
+#define MVFR1_MVE_MASK 0x00000F00
+#define MVFR1_MVE_I    0x00000100
+#define MVFR1_MVE_F    0x00000200
 
 static int cortex_m_find_mem_ap(struct adiv5_dap *swjdp,
                struct adiv5_ap **debug_ap)
@@ -2509,7 +2510,7 @@ static int cortex_m_find_mem_ap(struct adiv5_dap *swjdp,
 int cortex_m_examine(struct target *target)
 {
        int retval;
-       uint32_t cpuid, fpcr, mvfr0, mvfr1;
+       uint32_t cpuid, fpcr;
        struct cortex_m_common *cortex_m = target_to_cm(target);
        struct adiv5_dap *swjdp = cortex_m->armv7m.arm.dap;
        struct armv7m_common *armv7m = target_to_armv7m(target);
@@ -2584,25 +2585,37 @@ int cortex_m_examine(struct target *target)
                LOG_TARGET_DEBUG(target, "cpuid: 0x%8.8" PRIx32 "", cpuid);
 
                if (cortex_m->core_info->flags & CORTEX_M_F_HAS_FPV4) {
+                       uint32_t mvfr0;
                        target_read_u32(target, MVFR0, &mvfr0);
-                       target_read_u32(target, MVFR1, &mvfr1);
 
-                       /* test for floating point feature on Cortex-M4 */
-                       if ((mvfr0 == MVFR0_DEFAULT_M4) && (mvfr1 == MVFR1_DEFAULT_M4)) {
-                               LOG_TARGET_DEBUG(target, "%s floating point feature FPv4_SP found", cortex_m->core_info->name);
+                       if ((mvfr0 & MVFR0_SP_MASK) == MVFR0_SP) {
+                               LOG_TARGET_DEBUG(target, "%s floating point feature FPv4_SP found",
+                                               cortex_m->core_info->name);
                                armv7m->fp_feature = FPV4_SP;
                        }
                } else if (cortex_m->core_info->flags & CORTEX_M_F_HAS_FPV5) {
+                       uint32_t mvfr0, mvfr1;
                        target_read_u32(target, MVFR0, &mvfr0);
                        target_read_u32(target, MVFR1, &mvfr1);
 
-                       /* test for floating point features on Cortex-M7 */
-                       if ((mvfr0 == MVFR0_DEFAULT_M7_SP) && (mvfr1 == MVFR1_DEFAULT_M7_SP)) {
-                               LOG_TARGET_DEBUG(target, "%s floating point feature FPv5_SP found", cortex_m->core_info->name);
+                       if ((mvfr0 & MVFR0_DP_MASK) == MVFR0_DP) {
+                               if ((mvfr1 & MVFR1_MVE_MASK) == MVFR1_MVE_F) {
+                                       LOG_TARGET_DEBUG(target, "%s floating point feature FPv5_DP + MVE-F found",
+                                                       cortex_m->core_info->name);
+                                       armv7m->fp_feature = FPV5_MVE_F;
+                               } else {
+                                       LOG_TARGET_DEBUG(target, "%s floating point feature FPv5_DP found",
+                                                       cortex_m->core_info->name);
+                                       armv7m->fp_feature = FPV5_DP;
+                               }
+                       } else if ((mvfr0 & MVFR0_SP_MASK) == MVFR0_SP) {
+                               LOG_TARGET_DEBUG(target, "%s floating point feature FPv5_SP found",
+                                               cortex_m->core_info->name);
                                armv7m->fp_feature = FPV5_SP;
-                       } else if ((mvfr0 == MVFR0_DEFAULT_M7_DP) && (mvfr1 == MVFR1_DEFAULT_M7_DP)) {
-                               LOG_TARGET_DEBUG(target, "%s floating point feature FPv5_DP found", cortex_m->core_info->name);
-                               armv7m->fp_feature = FPV5_DP;
+                       } else if ((mvfr1 & MVFR1_MVE_MASK) == MVFR1_MVE_I) {
+                               LOG_TARGET_DEBUG(target, "%s floating point feature MVE-I found",
+                                               cortex_m->core_info->name);
+                               armv7m->fp_feature = FPV5_MVE_I;
                        }
                }