[Qemu-devel] [PATCH v2 3/7] target-arm: Add arm_ccnt_enabled function

[Alistair Francis]

Include a helper function to determine if the CCNT counter
is enabled as well as the constants used to mask the pmccfiltr_el0
and c9_pmxevtyper registers.

Signed-off-by: Alistair Francis <address@hidden>
---

 target-arm/helper.c |   40 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 40 insertions(+), 0 deletions(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index ce986ee..141e252 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -547,6 +547,46 @@ static CPAccessResult pmreg_access(CPUARMState *env, const 
ARMCPRegInfo *ri)
 }
 
 #ifndef CONFIG_USER_ONLY
+#define PMCCFILTR_NSH 0x8000000
+#define PMCCFILTR_P 0x80000000
+#define PMCCFILTR_U 0x40000000
+
+#define PMXEVTYPER_P 0x80000000
+#define PMXEVTYPER_U 0x40000000
+
+static bool arm_ccnt_enabled(CPUARMState *env)
+{
+    /* This does not support checking for the secure/non-secure
+     * components of the PMCCFILTR_EL0 register
+     */
+
+    if (!(env->cp15.c9_pmcr & PMCRE)) {
+        return 0;
+    }
+
+    if (arm_current_pl(env) == 2) {
+        if (!(env->cp15.pmccfiltr_el0 & PMCCFILTR_NSH)) {
+            return 0;
+        }
+    } else if (arm_current_pl(env) == 1) {
+        if (env->cp15.pmccfiltr_el0 & PMCCFILTR_P) {
+            return 0;
+        } else if (env->cp15.c9_pmxevtyper & PMXEVTYPER_P) {
+            return 0;
+        }
+    } else if (arm_current_pl(env) == 0) {
+        if (env->cp15.pmccfiltr_el0 & PMCCFILTR_U) {
+            return 0;
+        } else if (env->cp15.c9_pmxevtyper & PMXEVTYPER_U) {
+            return 0;
+        }
+    }
+
+    return 1;
+}
+#endif
+
+#ifndef CONFIG_USER_ONLY
 static void pmcr_write(CPUARMState *env, const ARMCPRegInfo *ri,
                        uint64_t value)
 {
-- 
1.7.1