arch/armv8-r64: userspace PMU access

Enable ARCH_HAVE_PERF_EVENTS_USER_ACCESS capability for Cortex-R82 to
allow userspace applications to directly access hardware performance
counters. Move up_perf_gettime() outside kernel-only block so it can
be called from userspace for efficient profiling.

Signed-off-by: hujun5 <hujun5@xiaomi.com>

arch/arm64/Kconfig

@@ -340,6 +340,7 @@ config ARCH_CORTEX_R82
 	select ARCH_HAVE_CLUSTER_PMU
 	select ARCH_HAVE_TESTSET
 	select ARM64_HAVE_NEON
+	select ARCH_HAVE_PERF_EVENTS_USER_ACCESS if !ARCH_CLUSTER_PMU
 
 config ARCH_CPU_UNKNOWN
 	bool

arch/arm64/src/common/CMakeLists.txt

@@ -142,6 +142,11 @@ endif()
 
 target_sources(arch PRIVATE ${SRCS})
 
+if(NOT CONFIG_BUILD_FLAT AND CONFIG_ARCH_HAVE_PERF_EVENTS_USER_ACCESS)
+  target_sources(arch_interface PRIVATE arm64_perf.c)
+  target_include_directories(arch_interface PRIVATE ${NUTTX_CHIP_ABS_DIR})
+endif()
+
 nuttx_add_aux_library(STARTUP_OBJS crt0.c)
 
 target_compile_options(

arch/arm64/src/common/Make.defs

@@ -141,3 +141,7 @@ endif
 ifeq ($(CONFIG_ARM64_SEMIHOSTING_HOSTFS),y)
   CMN_CSRCS += arm64_hostfs.c
 endif
+
+ifeq ($(CONFIG_ARCH_HAVE_PERF_EVENTS_USER_ACCESS),y)
+  CMN_UCSRCS += arm64_perf.c
+endif

arch/arm64/src/common/arm64_perf.c

@@ -30,6 +30,7 @@
 
 #ifdef CONFIG_ARCH_HAVE_PERF_EVENTS
 
+#  if defined(CONFIG_BUILD_FLAT) || defined(__KERNEL__)
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -64,15 +65,6 @@ unsigned long up_perf_getfreq(void)
   return g_cpu_freq;
 }
 
-clock_t up_perf_gettime(void)
-{
-#ifdef CONFIG_ARCH_CLUSTER_PMU
-  return pmu_get_cluccntr();
-#else
-  return pmu_get_ccntr();
-#endif
-}
-
 void up_perf_convert(clock_t elapsed, struct timespec *ts)
 {
   clock_t left;
@@ -81,4 +73,15 @@ void up_perf_convert(clock_t elapsed, struct timespec *ts)
   left        = elapsed - ts->tv_sec * g_cpu_freq;
   ts->tv_nsec = NSEC_PER_SEC * left / g_cpu_freq;
 }
+#  endif /* CONFIG_BUILD_FLAT || __KERNEL__ */
+
+clock_t up_perf_gettime(void)
+{
+#  ifdef CONFIG_ARCH_CLUSTER_PMU
+  return pmu_get_cluccntr();
+#  else
+  return pmu_get_ccntr();
+#  endif
+}
+
 #endif