ARC: [SMP] Disallow RTSC

RTSC is strictly incore and must not be allowed in SMP configs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index fb4177e482604dec239129f89433ad99f29989e3..5ede5460c80692502730d69510a57975b386fe8d 100644 (file)
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -136,9 +136,6 @@ if SMP
 config ARC_HAS_COH_CACHES
        def_bool n
 
-config ARC_HAS_COH_RTSC
-       def_bool n
-
 config ARC_HAS_REENTRANT_IRQ_LV2
        def_bool n
 
@@ -332,8 +329,7 @@ config ARC_HAS_RTSC
        bool "Insn: RTSC (64-bit r/o cycle counter)"
        default y
        depends on ARC_CPU_REL_4_10
-       # if SMP, enable RTSC only if counter is coherent across cores
-       depends on !SMP || ARC_HAS_COH_RTSC
+       depends on !SMP
 
 endmenu   # "ARC CPU Configuration"
 

diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index 0a9b6b289c4f84369777a6aba460b3212cd6e9a5..e5f3a837fb35f2b4a37dc162f5b2054a1008ae15 100644 (file)
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -63,9 +63,10 @@
 
 int arc_counter_setup(void)
 {
-       /* RTSC insn taps into cpu clk, needs no setup */
-
-       /* For SMP, only allowed if cross-core-sync, hence usable as cs */
+       /*
+        * For SMP this needs to be 0. However Kconfig glue doesn't
+        * enable this option for SMP configs
+        */
        return 1;
 }