ARC: RIP broken 64bit RTSC
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index a35d57a..8e8de4c 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -311,11 +311,6 @@
bool "Insn: SWAPE (endian-swap)"
default y
-config ARC_HAS_RTSC
- bool "Insn: RTSC (64-bit r/o cycle counter)"
- default y
- depends on !SMP
-
endmenu # "ARC CPU Configuration"
config LINUX_LINK_BASE
diff --git a/arch/arc/Makefile b/arch/arc/Makefile
index 50bc5bc..87e0e5b 100644
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -33,7 +33,7 @@
cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock
cflags-$(CONFIG_ARC_HAS_SWAPE) += -mswape
-cflags-$(CONFIG_ARC_HAS_RTSC) += -mrtsc
+
cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables
# By default gcc 4.8 generates dwarf4 which kernel unwinder can't grok
diff --git a/arch/arc/configs/nsim_700_defconfig b/arch/arc/configs/nsim_700_defconfig
index 281baa0..e6aa1ed 100644
--- a/arch/arc/configs/nsim_700_defconfig
+++ b/arch/arc/configs/nsim_700_defconfig
@@ -23,7 +23,6 @@
# CONFIG_IOSCHED_DEADLINE is not set
# CONFIG_IOSCHED_CFQ is not set
CONFIG_ARC_PLAT_FPGA_LEGACY=y
-# CONFIG_ARC_HAS_RTSC is not set
CONFIG_ARC_BUILTIN_DTB_NAME="angel4"
CONFIG_PREEMPT=y
# CONFIG_COMPACTION is not set
diff --git a/arch/arc/configs/nsimosci_defconfig b/arch/arc/configs/nsimosci_defconfig
index 70d0de4..1aad236 100644
--- a/arch/arc/configs/nsimosci_defconfig
+++ b/arch/arc/configs/nsimosci_defconfig
@@ -24,7 +24,6 @@
# CONFIG_IOSCHED_DEADLINE is not set
# CONFIG_IOSCHED_CFQ is not set
CONFIG_ARC_PLAT_FPGA_LEGACY=y
-# CONFIG_ARC_HAS_RTSC is not set
CONFIG_ARC_BUILTIN_DTB_NAME="nsimosci"
# CONFIG_COMPACTION is not set
CONFIG_NET=y
diff --git a/arch/arc/configs/tb10x_defconfig b/arch/arc/configs/tb10x_defconfig
index 2242a06..3b4dc9c 100644
--- a/arch/arc/configs/tb10x_defconfig
+++ b/arch/arc/configs/tb10x_defconfig
@@ -26,7 +26,6 @@
# CONFIG_BLOCK is not set
CONFIG_ARC_PLAT_TB10X=y
CONFIG_ARC_CACHE_LINE_SHIFT=5
-# CONFIG_ARC_HAS_RTSC is not set
CONFIG_ARC_STACK_NONEXEC=y
CONFIG_HZ=250
CONFIG_ARC_BUILTIN_DTB_NAME="abilis_tb100_dvk"
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 1d167c6..5086c75 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -180,10 +180,9 @@
(unsigned int)(arc_get_core_freq() / 1000000),
(unsigned int)(arc_get_core_freq() / 10000) % 100);
- n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s%s%s\nISA Extn\t: ",
+ n += scnprintf(buf + n, len - n, "Timers\t\t: %s%s\nISA Extn\t: ",
IS_AVAIL1(cpu->timers.t0, "Timer0 "),
- IS_AVAIL1(cpu->timers.t1, "Timer1 "),
- IS_AVAIL2(cpu->timers.rtsc, "64-bit RTSC ", CONFIG_ARC_HAS_RTSC));
+ IS_AVAIL1(cpu->timers.t1, "Timer1 "));
n += i = scnprintf(buf + n, len - n, "%s%s",
IS_AVAIL2(atomic, "atomic ", CONFIG_ARC_HAS_LLSC));
@@ -254,9 +253,6 @@
if (!cpu->timers.t1)
panic("Timer1 is not present!\n");
- if (IS_ENABLED(CONFIG_ARC_HAS_RTSC) && !cpu->timers.rtsc)
- panic("RTSC is not present\n");
-
#ifdef CONFIG_ARC_HAS_DCCM
/*
* DCCM can be arbit placed in hardware.
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index dbe74f4..9307f87 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -26,6 +26,7 @@
* while TIMER1 for free running (clocksource)
*
* Newer ARC700 cores have 64bit clk fetching RTSC insn, preferred over TIMER1
+ * which however is currently broken
*/
#include <linux/spinlock.h>
@@ -59,52 +60,6 @@
/********** Clock Source Device *********/
-#ifdef CONFIG_ARC_HAS_RTSC
-
-int arc_counter_setup(void)
-{
- /*
- * For SMP this needs to be 0. However Kconfig glue doesn't
- * enable this option for SMP configs
- */
- return 1;
-}
-
-static cycle_t arc_counter_read(struct clocksource *cs)
-{
- unsigned long flags;
- union {
-#ifdef CONFIG_CPU_BIG_ENDIAN
- struct { u32 high, low; };
-#else
- struct { u32 low, high; };
-#endif
- cycle_t full;
- } stamp;
-
- flags = arch_local_irq_save();
-
- __asm__ __volatile(
- " .extCoreRegister tsch, 58, r, cannot_shortcut \n"
- " rtsc %0, 0 \n"
- " mov %1, 0 \n"
- : "=r" (stamp.low), "=r" (stamp.high));
-
- arch_local_irq_restore(flags);
-
- return stamp.full;
-}
-
-static struct clocksource arc_counter = {
- .name = "ARC RTSC",
- .rating = 300,
- .read = arc_counter_read,
- .mask = CLOCKSOURCE_MASK(32),
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-#else /* !CONFIG_ARC_HAS_RTSC */
-
static bool is_usable_as_clocksource(void)
{
#ifdef CONFIG_SMP
@@ -139,8 +94,6 @@
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-#endif
-
/********** Clock Event Device *********/
/*