arm64: move from arm_generic to arm_arch_timer
The arch_timer driver supports a superset of the functionality of the
arm_generic driver, and is not tied to a particular arch.
This patch moves arm64 to use the arch_timer driver, gaining additional
functionality in doing so, and removes the (now unused) arm_generic
driver. Timer-related hooks specific to arm64 are moved into
arch/arm64/kernel/time.c.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index f8f362a..2b6cef6 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -3,6 +3,7 @@
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
select ARM_AMBA
+ select ARM_ARCH_TIMER
select CLONE_BACKWARDS
select COMMON_CLK
select GENERIC_CLOCKEVENTS
diff --git a/arch/arm64/include/asm/arch_timer.h b/arch/arm64/include/asm/arch_timer.h
new file mode 100644
index 0000000..91e2a6a
--- /dev/null
+++ b/arch/arm64/include/asm/arch_timer.h
@@ -0,0 +1,133 @@
+/*
+ * arch/arm64/include/asm/arch_timer.h
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_ARCH_TIMER_H
+#define __ASM_ARCH_TIMER_H
+
+#include <asm/barrier.h>
+
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <clocksource/arm_arch_timer.h>
+
+static inline void arch_timer_reg_write(int access, int reg, u32 val)
+{
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("msr cntp_ctl_el0, %0" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("msr cntv_ctl_el0, %0" : : "r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("msr cntv_tval_el0, %0" : : "r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else {
+ BUILD_BUG();
+ }
+
+ isb();
+}
+
+static inline u32 arch_timer_reg_read(int access, int reg)
+{
+ u32 val;
+
+ if (access == ARCH_TIMER_PHYS_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else if (access == ARCH_TIMER_VIRT_ACCESS) {
+ switch (reg) {
+ case ARCH_TIMER_REG_CTRL:
+ asm volatile("mrs %0, cntv_ctl_el0" : "=r" (val));
+ break;
+ case ARCH_TIMER_REG_TVAL:
+ asm volatile("mrs %0, cntv_tval_el0" : "=r" (val));
+ break;
+ default:
+ BUILD_BUG();
+ }
+ } else {
+ BUILD_BUG();
+ }
+
+ return val;
+}
+
+static inline u32 arch_timer_get_cntfrq(void)
+{
+ u32 val;
+ asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
+ return val;
+}
+
+static inline void __cpuinit arch_counter_set_user_access(void)
+{
+ u32 cntkctl;
+
+ /* Disable user access to the timers and the physical counter. */
+ asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
+ cntkctl &= ~((3 << 8) | (1 << 0));
+
+ /* Enable user access to the virtual counter and frequency. */
+ cntkctl |= (1 << 1);
+ asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
+}
+
+static inline u64 arch_counter_get_cntpct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
+
+ return cval;
+}
+
+static inline u64 arch_counter_get_cntvct(void)
+{
+ u64 cval;
+
+ isb();
+ asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
+
+ return cval;
+}
+
+#endif
diff --git a/arch/arm64/include/asm/arm_generic.h b/arch/arm64/include/asm/arm_generic.h
deleted file mode 100644
index 6ece2f1..0000000
--- a/arch/arm64/include/asm/arm_generic.h
+++ /dev/null
@@ -1,102 +0,0 @@
-/*
- * arch/arm64/include/asm/arm_generic.h
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Marc Zyngier <marc.zyngier@arm.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
-#ifndef __ASM_ARM_GENERIC_H
-#define __ASM_ARM_GENERIC_H
-
-#include <linux/clocksource.h>
-
-#define ARCH_TIMER_CTRL_ENABLE (1 << 0)
-#define ARCH_TIMER_CTRL_IMASK (1 << 1)
-#define ARCH_TIMER_CTRL_ISTATUS (1 << 2)
-
-#define ARCH_TIMER_REG_CTRL 0
-#define ARCH_TIMER_REG_FREQ 1
-#define ARCH_TIMER_REG_TVAL 2
-
-static inline void arch_timer_reg_write(int reg, u32 val)
-{
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("msr cntp_ctl_el0, %0" : : "r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("msr cntp_tval_el0, %0" : : "r" (val));
- break;
- default:
- BUILD_BUG();
- }
-
- isb();
-}
-
-static inline u32 arch_timer_reg_read(int reg)
-{
- u32 val;
-
- switch (reg) {
- case ARCH_TIMER_REG_CTRL:
- asm volatile("mrs %0, cntp_ctl_el0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_FREQ:
- asm volatile("mrs %0, cntfrq_el0" : "=r" (val));
- break;
- case ARCH_TIMER_REG_TVAL:
- asm volatile("mrs %0, cntp_tval_el0" : "=r" (val));
- break;
- default:
- BUILD_BUG();
- }
-
- return val;
-}
-
-static inline void __cpuinit arch_counter_enable_user_access(void)
-{
- u32 cntkctl;
-
- /* Disable user access to the timers and the physical counter. */
- asm volatile("mrs %0, cntkctl_el1" : "=r" (cntkctl));
- cntkctl &= ~((3 << 8) | (1 << 0));
-
- /* Enable user access to the virtual counter and frequency. */
- cntkctl |= (1 << 1);
- asm volatile("msr cntkctl_el1, %0" : : "r" (cntkctl));
-}
-
-static inline cycle_t arch_counter_get_cntpct(void)
-{
- cycle_t cval;
-
- isb();
- asm volatile("mrs %0, cntpct_el0" : "=r" (cval));
-
- return cval;
-}
-
-static inline cycle_t arch_counter_get_cntvct(void)
-{
- cycle_t cval;
-
- isb();
- asm volatile("mrs %0, cntvct_el0" : "=r" (cval));
-
- return cval;
-}
-
-#endif
diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index 3b4b725..b0ef18d1 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -31,8 +31,9 @@
#include <linux/syscore_ops.h>
#include <linux/timer.h>
#include <linux/irq.h>
+#include <linux/delay.h>
-#include <clocksource/arm_generic.h>
+#include <clocksource/arm_arch_timer.h>
#include <asm/thread_info.h>
#include <asm/stacktrace.h>
@@ -59,7 +60,31 @@
EXPORT_SYMBOL(profile_pc);
#endif
+static u64 sched_clock_mult __read_mostly;
+
+unsigned long long notrace sched_clock(void)
+{
+ return arch_timer_read_counter() * sched_clock_mult;
+}
+
+int read_current_timer(unsigned long *timer_value)
+{
+ *timer_value = arch_timer_read_counter();
+ return 0;
+}
+
void __init time_init(void)
{
- arm_generic_timer_init();
+ u32 arch_timer_rate;
+
+ if (arch_timer_init())
+ panic("Unable to initialise architected timer.\n");
+
+ arch_timer_rate = arch_timer_get_rate();
+
+ /* Cache the sched_clock multiplier to save a divide in the hot path. */
+ sched_clock_mult = NSEC_PER_SEC / arch_timer_rate;
+
+ /* Calibrate the delay loop directly */
+ lpj_fine = arch_timer_rate / HZ;
}
