Linus,
please pull the latest timers/core branch from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
timers-core-2020-10-12
up to: 1b80043ed218: clocksource/drivers/armada-370-xp: Use semicolons rather
than commas to separate statements
Updates for timekeeping, timers and related drivers:
Core:
- Early boot support for the NMI safe timekeeper by utilizing
local_clock() up to the point where timekeeping is initialized. This
allows printk() to store multiple timestamps in the ringbuffer which is
useful for coordinating dmesg information across a fleet of machines.
- Provide a multi-timestamp accessor for printk()
- Make timer init more robust by checking for invalid timer flags.
- Comma vs. semicolon fixes
Drivers:
- Support for new platforms in existing drivers (SP804 and Renesas CMT)
- Comma vs. semicolon fixes
Thanks,
tglx
------------------>
Julia Lawall (2):
clocksource/drivers/mps2-timer: Use semicolons rather than commas to
separate statements
clocksource/drivers/armada-370-xp: Use semicolons rather than commas to
separate statements
Kefeng Wang (1):
clocksource/drivers/sp804: Cleanup clk_get_sys()
Lad Prabhakar (2):
dt-bindings: timer: renesas,cmt: Document r8a7742 CMT support
dt-bindings: timer: renesas,cmt: Document r8a774e1 CMT support
Qianli Zhao (1):
timers: Mask invalid flags in do_init_timer()
Thomas Gleixner (2):
timekeeping: Utilize local_clock() for NMI safe timekeeper during early
boot
timekeeping: Provide multi-timestamp accessor to NMI safe timekeeper
Xu Wang (1):
alarmtimer: Convert comma to semicolon
Zhen Lei (7):
clocksource/drivers/sp804: Remove unused sp804_timer_disable() and
timer-sp804.h
clocksource/drivers/sp804: Delete the leading "__" of some functions
clocksource/drivers/sp804: Remove a mismatched comment
clocksource/drivers/sp804: Prepare for support non-standard register
offset
clocksource/drivers/sp804: Support non-standard register offset
clocksource/drivers/sp804: Add support for Hisilicon sp804 timer
clocksource/drivers/sp804: Enable Hisilicon sp804 timer 64bit mode
.../devicetree/bindings/timer/renesas,cmt.yaml | 4 +
drivers/clocksource/mps2-timer.c | 6 +-
drivers/clocksource/timer-armada-370-xp.c | 8 +-
drivers/clocksource/timer-sp.h | 32 ++++
drivers/clocksource/timer-sp804.c | 210 ++++++++++++++-------
include/clocksource/timer-sp804.h | 29 ---
include/linux/timekeeping.h | 15 ++
include/linux/timer.h | 1 +
kernel/time/alarmtimer.c | 2 +-
kernel/time/timekeeping.c | 109 +++++++++--
kernel/time/timer.c | 2 +
11 files changed, 299 insertions(+), 119 deletions(-)
delete mode 100644 include/clocksource/timer-sp804.h
diff --git a/Documentation/devicetree/bindings/timer/renesas,cmt.yaml
b/Documentation/devicetree/bindings/timer/renesas,cmt.yaml
index 7e4dc5623da8..428db3a21bb9 100644
--- a/Documentation/devicetree/bindings/timer/renesas,cmt.yaml
+++ b/Documentation/devicetree/bindings/timer/renesas,cmt.yaml
@@ -39,6 +39,7 @@ properties:
- items:
- enum:
- renesas,r8a73a4-cmt0 # 32-bit CMT0 on R-Mobile APE6
+ - renesas,r8a7742-cmt0 # 32-bit CMT0 on RZ/G1H
- renesas,r8a7743-cmt0 # 32-bit CMT0 on RZ/G1M
- renesas,r8a7744-cmt0 # 32-bit CMT0 on RZ/G1N
- renesas,r8a7745-cmt0 # 32-bit CMT0 on RZ/G1E
@@ -53,6 +54,7 @@ properties:
- items:
- enum:
- renesas,r8a73a4-cmt1 # 48-bit CMT1 on R-Mobile APE6
+ - renesas,r8a7742-cmt1 # 48-bit CMT1 on RZ/G1H
- renesas,r8a7743-cmt1 # 48-bit CMT1 on RZ/G1M
- renesas,r8a7744-cmt1 # 48-bit CMT1 on RZ/G1N
- renesas,r8a7745-cmt1 # 48-bit CMT1 on RZ/G1E
@@ -69,6 +71,7 @@ properties:
- renesas,r8a774a1-cmt0 # 32-bit CMT0 on RZ/G2M
- renesas,r8a774b1-cmt0 # 32-bit CMT0 on RZ/G2N
- renesas,r8a774c0-cmt0 # 32-bit CMT0 on RZ/G2E
+ - renesas,r8a774e1-cmt0 # 32-bit CMT0 on RZ/G2H
- renesas,r8a7795-cmt0 # 32-bit CMT0 on R-Car H3
- renesas,r8a7796-cmt0 # 32-bit CMT0 on R-Car M3-W
- renesas,r8a77965-cmt0 # 32-bit CMT0 on R-Car M3-N
@@ -83,6 +86,7 @@ properties:
- renesas,r8a774a1-cmt1 # 48-bit CMT on RZ/G2M
- renesas,r8a774b1-cmt1 # 48-bit CMT on RZ/G2N
- renesas,r8a774c0-cmt1 # 48-bit CMT on RZ/G2E
+ - renesas,r8a774e1-cmt1 # 48-bit CMT on RZ/G2H
- renesas,r8a7795-cmt1 # 48-bit CMT on R-Car H3
- renesas,r8a7796-cmt1 # 48-bit CMT on R-Car M3-W
- renesas,r8a77965-cmt1 # 48-bit CMT on R-Car M3-N
diff --git a/drivers/clocksource/mps2-timer.c b/drivers/clocksource/mps2-timer.c
index 2e64d984c83a..efe8cad8f2a5 100644
--- a/drivers/clocksource/mps2-timer.c
+++ b/drivers/clocksource/mps2-timer.c
@@ -149,9 +149,9 @@ static int __init mps2_clockevent_init(struct device_node
*np)
ce->clkevt.rating = 200;
ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
ce->clkevt.cpumask = cpu_possible_mask;
- ce->clkevt.set_state_shutdown = mps2_timer_shutdown,
- ce->clkevt.set_state_periodic = mps2_timer_set_periodic,
- ce->clkevt.set_state_oneshot = mps2_timer_shutdown,
+ ce->clkevt.set_state_shutdown = mps2_timer_shutdown;
+ ce->clkevt.set_state_periodic = mps2_timer_set_periodic;
+ ce->clkevt.set_state_oneshot = mps2_timer_shutdown;
ce->clkevt.set_next_event = mps2_timer_set_next_event;
/* Ensure timer is disabled */
diff --git a/drivers/clocksource/timer-armada-370-xp.c
b/drivers/clocksource/timer-armada-370-xp.c
index edf1a46269f1..e3acc3c631b7 100644
--- a/drivers/clocksource/timer-armada-370-xp.c
+++ b/drivers/clocksource/timer-armada-370-xp.c
@@ -181,12 +181,12 @@ static int armada_370_xp_timer_starting_cpu(unsigned int
cpu)
clr = TIMER0_25MHZ;
local_timer_ctrl_clrset(clr, set);
- evt->name = "armada_370_xp_per_cpu_tick",
+ evt->name = "armada_370_xp_per_cpu_tick";
evt->features = CLOCK_EVT_FEAT_ONESHOT |
CLOCK_EVT_FEAT_PERIODIC;
- evt->shift = 32,
- evt->rating = 300,
- evt->set_next_event = armada_370_xp_clkevt_next_event,
+ evt->shift = 32;
+ evt->rating = 300;
+ evt->set_next_event = armada_370_xp_clkevt_next_event;
evt->set_state_shutdown = armada_370_xp_clkevt_shutdown;
evt->set_state_periodic = armada_370_xp_clkevt_set_periodic;
evt->set_state_oneshot = armada_370_xp_clkevt_shutdown;
diff --git a/drivers/clocksource/timer-sp.h b/drivers/clocksource/timer-sp.h
index b2037eb94a41..811f840be0e5 100644
--- a/drivers/clocksource/timer-sp.h
+++ b/drivers/clocksource/timer-sp.h
@@ -10,6 +10,7 @@
*
* Every SP804 contains two identical timers.
*/
+#define NR_TIMERS 2
#define TIMER_1_BASE 0x00
#define TIMER_2_BASE 0x20
@@ -29,3 +30,34 @@
#define TIMER_RIS 0x10 /* CVR ro */
#define TIMER_MIS 0x14 /* CVR ro */
#define TIMER_BGLOAD 0x18 /* CVR rw */
+
+struct sp804_timer {
+ int load;
+ int load_h;
+ int value;
+ int value_h;
+ int ctrl;
+ int intclr;
+ int ris;
+ int mis;
+ int bgload;
+ int bgload_h;
+ int timer_base[NR_TIMERS];
+ int width;
+};
+
+struct sp804_clkevt {
+ void __iomem *base;
+ void __iomem *load;
+ void __iomem *load_h;
+ void __iomem *value;
+ void __iomem *value_h;
+ void __iomem *ctrl;
+ void __iomem *intclr;
+ void __iomem *ris;
+ void __iomem *mis;
+ void __iomem *bgload;
+ void __iomem *bgload_h;
+ unsigned long reload;
+ int width;
+};
diff --git a/drivers/clocksource/timer-sp804.c
b/drivers/clocksource/timer-sp804.c
index 5cd0abf9b396..6e8ad4a4ea3c 100644
--- a/drivers/clocksource/timer-sp804.c
+++ b/drivers/clocksource/timer-sp804.c
@@ -18,15 +18,57 @@
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
-#include <clocksource/timer-sp804.h>
-
#include "timer-sp.h"
-static long __init sp804_get_clock_rate(struct clk *clk)
+/* Hisilicon 64-bit timer(a variant of ARM SP804) */
+#define HISI_TIMER_1_BASE 0x00
+#define HISI_TIMER_2_BASE 0x40
+#define HISI_TIMER_LOAD 0x00
+#define HISI_TIMER_LOAD_H 0x04
+#define HISI_TIMER_VALUE 0x08
+#define HISI_TIMER_VALUE_H 0x0c
+#define HISI_TIMER_CTRL 0x10
+#define HISI_TIMER_INTCLR 0x14
+#define HISI_TIMER_RIS 0x18
+#define HISI_TIMER_MIS 0x1c
+#define HISI_TIMER_BGLOAD 0x20
+#define HISI_TIMER_BGLOAD_H 0x24
+
+
+struct sp804_timer __initdata arm_sp804_timer = {
+ .load = TIMER_LOAD,
+ .value = TIMER_VALUE,
+ .ctrl = TIMER_CTRL,
+ .intclr = TIMER_INTCLR,
+ .timer_base = {TIMER_1_BASE, TIMER_2_BASE},
+ .width = 32,
+};
+
+struct sp804_timer __initdata hisi_sp804_timer = {
+ .load = HISI_TIMER_LOAD,
+ .load_h = HISI_TIMER_LOAD_H,
+ .value = HISI_TIMER_VALUE,
+ .value_h = HISI_TIMER_VALUE_H,
+ .ctrl = HISI_TIMER_CTRL,
+ .intclr = HISI_TIMER_INTCLR,
+ .timer_base = {HISI_TIMER_1_BASE, HISI_TIMER_2_BASE},
+ .width = 64,
+};
+
+static struct sp804_clkevt sp804_clkevt[NR_TIMERS];
+
+static long __init sp804_get_clock_rate(struct clk *clk, const char *name)
{
long rate;
int err;
+ if (!clk)
+ clk = clk_get_sys("sp804", name);
+ if (IS_ERR(clk)) {
+ pr_err("sp804: %s clock not found: %ld\n", name, PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+
err = clk_prepare(clk);
if (err) {
pr_err("sp804: clock failed to prepare: %d\n", err);
@@ -53,50 +95,57 @@ static long __init sp804_get_clock_rate(struct clk *clk)
return rate;
}
-static void __iomem *sched_clock_base;
-
-static u64 notrace sp804_read(void)
+static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base)
{
- return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
+ int i;
+
+ for (i = 0; i < NR_TIMERS; i++) {
+ if (sp804_clkevt[i].base == base)
+ return &sp804_clkevt[i];
+ }
+
+ /* It's impossible to reach here */
+ WARN_ON(1);
+
+ return NULL;
}
-void __init sp804_timer_disable(void __iomem *base)
+static struct sp804_clkevt *sched_clkevt;
+
+static u64 notrace sp804_read(void)
{
- writel(0, base + TIMER_CTRL);
+ return ~readl_relaxed(sched_clkevt->value);
}
-int __init __sp804_clocksource_and_sched_clock_init(void __iomem *base,
- const char *name,
- struct clk *clk,
- int use_sched_clock)
+int __init sp804_clocksource_and_sched_clock_init(void __iomem *base,
+ const char *name,
+ struct clk *clk,
+ int use_sched_clock)
{
long rate;
+ struct sp804_clkevt *clkevt;
- if (!clk) {
- clk = clk_get_sys("sp804", name);
- if (IS_ERR(clk)) {
- pr_err("sp804: clock not found: %d\n",
- (int)PTR_ERR(clk));
- return PTR_ERR(clk);
- }
- }
-
- rate = sp804_get_clock_rate(clk);
+ rate = sp804_get_clock_rate(clk, name);
if (rate < 0)
return -EINVAL;
- /* setup timer 0 as free-running clocksource */
- writel(0, base + TIMER_CTRL);
- writel(0xffffffff, base + TIMER_LOAD);
- writel(0xffffffff, base + TIMER_VALUE);
+ clkevt = sp804_clkevt_get(base);
+
+ writel(0, clkevt->ctrl);
+ writel(0xffffffff, clkevt->load);
+ writel(0xffffffff, clkevt->value);
+ if (clkevt->width == 64) {
+ writel(0xffffffff, clkevt->load_h);
+ writel(0xffffffff, clkevt->value_h);
+ }
writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
- base + TIMER_CTRL);
+ clkevt->ctrl);
- clocksource_mmio_init(base + TIMER_VALUE, name,
+ clocksource_mmio_init(clkevt->value, name,
rate, 200, 32, clocksource_mmio_readl_down);
if (use_sched_clock) {
- sched_clock_base = base;
+ sched_clkevt = clkevt;
sched_clock_register(sp804_read, 32, rate);
}
@@ -104,8 +153,7 @@ int __init __sp804_clocksource_and_sched_clock_init(void
__iomem *base,
}
-static void __iomem *clkevt_base;
-static unsigned long clkevt_reload;
+static struct sp804_clkevt *common_clkevt;
/*
* IRQ handler for the timer
@@ -115,7 +163,7 @@ static irqreturn_t sp804_timer_interrupt(int irq, void
*dev_id)
struct clock_event_device *evt = dev_id;
/* clear the interrupt */
- writel(1, clkevt_base + TIMER_INTCLR);
+ writel(1, common_clkevt->intclr);
evt->event_handler(evt);
@@ -124,7 +172,7 @@ static irqreturn_t sp804_timer_interrupt(int irq, void
*dev_id)
static inline void timer_shutdown(struct clock_event_device *evt)
{
- writel(0, clkevt_base + TIMER_CTRL);
+ writel(0, common_clkevt->ctrl);
}
static int sp804_shutdown(struct clock_event_device *evt)
@@ -139,8 +187,8 @@ static int sp804_set_periodic(struct clock_event_device
*evt)
TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
timer_shutdown(evt);
- writel(clkevt_reload, clkevt_base + TIMER_LOAD);
- writel(ctrl, clkevt_base + TIMER_CTRL);
+ writel(common_clkevt->reload, common_clkevt->load);
+ writel(ctrl, common_clkevt->ctrl);
return 0;
}
@@ -150,8 +198,8 @@ static int sp804_set_next_event(unsigned long next,
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
- writel(next, clkevt_base + TIMER_LOAD);
- writel(ctrl, clkevt_base + TIMER_CTRL);
+ writel(next, common_clkevt->load);
+ writel(ctrl, common_clkevt->ctrl);
return 0;
}
@@ -168,30 +216,23 @@ static struct clock_event_device sp804_clockevent = {
.rating = 300,
};
-int __init __sp804_clockevents_init(void __iomem *base, unsigned int irq,
struct clk *clk, const char *name)
+int __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
+ struct clk *clk, const char *name)
{
struct clock_event_device *evt = &sp804_clockevent;
long rate;
- if (!clk)
- clk = clk_get_sys("sp804", name);
- if (IS_ERR(clk)) {
- pr_err("sp804: %s clock not found: %d\n", name,
- (int)PTR_ERR(clk));
- return PTR_ERR(clk);
- }
-
- rate = sp804_get_clock_rate(clk);
+ rate = sp804_get_clock_rate(clk, name);
if (rate < 0)
return -EINVAL;
- clkevt_base = base;
- clkevt_reload = DIV_ROUND_CLOSEST(rate, HZ);
+ common_clkevt = sp804_clkevt_get(base);
+ common_clkevt->reload = DIV_ROUND_CLOSEST(rate, HZ);
evt->name = name;
evt->irq = irq;
evt->cpumask = cpu_possible_mask;
- writel(0, base + TIMER_CTRL);
+ writel(0, common_clkevt->ctrl);
if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
"timer", &sp804_clockevent))
@@ -201,10 +242,33 @@ int __init __sp804_clockevents_init(void __iomem *base,
unsigned int irq, struct
return 0;
}
-static int __init sp804_of_init(struct device_node *np)
+static void __init sp804_clkevt_init(struct sp804_timer *timer, void __iomem
*base)
+{
+ int i;
+
+ for (i = 0; i < NR_TIMERS; i++) {
+ void __iomem *timer_base;
+ struct sp804_clkevt *clkevt;
+
+ timer_base = base + timer->timer_base[i];
+ clkevt = &sp804_clkevt[i];
+ clkevt->base = timer_base;
+ clkevt->load = timer_base + timer->load;
+ clkevt->load_h = timer_base + timer->load_h;
+ clkevt->value = timer_base + timer->value;
+ clkevt->value_h = timer_base + timer->value_h;
+ clkevt->ctrl = timer_base + timer->ctrl;
+ clkevt->intclr = timer_base + timer->intclr;
+ clkevt->width = timer->width;
+ }
+}
+
+static int __init sp804_of_init(struct device_node *np, struct sp804_timer
*timer)
{
static bool initialized = false;
void __iomem *base;
+ void __iomem *timer1_base;
+ void __iomem *timer2_base;
int irq, ret = -EINVAL;
u32 irq_num = 0;
struct clk *clk1, *clk2;
@@ -214,9 +278,12 @@ static int __init sp804_of_init(struct device_node *np)
if (!base)
return -ENXIO;
+ timer1_base = base + timer->timer_base[0];
+ timer2_base = base + timer->timer_base[1];
+
/* Ensure timers are disabled */
- writel(0, base + TIMER_CTRL);
- writel(0, base + TIMER_2_BASE + TIMER_CTRL);
+ writel(0, timer1_base + timer->ctrl);
+ writel(0, timer2_base + timer->ctrl);
if (initialized || !of_device_is_available(np)) {
ret = -EINVAL;
@@ -242,24 +309,27 @@ static int __init sp804_of_init(struct device_node *np)
if (irq <= 0)
goto err;
+ sp804_clkevt_init(timer, base);
+
of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
if (irq_num == 2) {
- ret = __sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2,
name);
+ ret = sp804_clockevents_init(timer2_base, irq, clk2, name);
if (ret)
goto err;
- ret = __sp804_clocksource_and_sched_clock_init(base, name,
clk1, 1);
+ ret = sp804_clocksource_and_sched_clock_init(timer1_base,
+ name, clk1, 1);
if (ret)
goto err;
} else {
- ret = __sp804_clockevents_init(base, irq, clk1 , name);
+ ret = sp804_clockevents_init(timer1_base, irq, clk1, name);
if (ret)
goto err;
- ret =__sp804_clocksource_and_sched_clock_init(base +
TIMER_2_BASE,
- name, clk2, 1);
+ ret = sp804_clocksource_and_sched_clock_init(timer2_base,
+ name, clk2, 1);
if (ret)
goto err;
}
@@ -270,7 +340,18 @@ static int __init sp804_of_init(struct device_node *np)
iounmap(base);
return ret;
}
-TIMER_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
+
+static int __init arm_sp804_of_init(struct device_node *np)
+{
+ return sp804_of_init(np, &arm_sp804_timer);
+}
+TIMER_OF_DECLARE(sp804, "arm,sp804", arm_sp804_of_init);
+
+static int __init hisi_sp804_of_init(struct device_node *np)
+{
+ return sp804_of_init(np, &hisi_sp804_timer);
+}
+TIMER_OF_DECLARE(hisi_sp804, "hisilicon,sp804", hisi_sp804_of_init);
static int __init integrator_cp_of_init(struct device_node *np)
{
@@ -293,13 +374,16 @@ static int __init integrator_cp_of_init(struct
device_node *np)
}
/* Ensure timer is disabled */
- writel(0, base + TIMER_CTRL);
+ writel(0, base + arm_sp804_timer.ctrl);
if (init_count == 2 || !of_device_is_available(np))
goto err;
+ sp804_clkevt_init(&arm_sp804_timer, base);
+
if (!init_count) {
- ret = __sp804_clocksource_and_sched_clock_init(base, name, clk,
0);
+ ret = sp804_clocksource_and_sched_clock_init(base,
+ name, clk, 0);
if (ret)
goto err;
} else {
@@ -307,7 +391,7 @@ static int __init integrator_cp_of_init(struct device_node
*np)
if (irq <= 0)
goto err;
- ret = __sp804_clockevents_init(base, irq, clk, name);
+ ret = sp804_clockevents_init(base, irq, clk, name);
if (ret)
goto err;
}
diff --git a/include/clocksource/timer-sp804.h
b/include/clocksource/timer-sp804.h
deleted file mode 100644
index a5b41f31a1c2..000000000000
--- a/include/clocksource/timer-sp804.h
+++ /dev/null
@@ -1,29 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __CLKSOURCE_TIMER_SP804_H
-#define __CLKSOURCE_TIMER_SP804_H
-
-struct clk;
-
-int __sp804_clocksource_and_sched_clock_init(void __iomem *,
- const char *, struct clk *, int);
-int __sp804_clockevents_init(void __iomem *, unsigned int,
- struct clk *, const char *);
-void sp804_timer_disable(void __iomem *);
-
-static inline void sp804_clocksource_init(void __iomem *base, const char *name)
-{
- __sp804_clocksource_and_sched_clock_init(base, name, NULL, 0);
-}
-
-static inline void sp804_clocksource_and_sched_clock_init(void __iomem *base,
- const char *name)
-{
- __sp804_clocksource_and_sched_clock_init(base, name, NULL, 1);
-}
-
-static inline void sp804_clockevents_init(void __iomem *base, unsigned int
irq, const char *name)
-{
- __sp804_clockevents_init(base, irq, NULL, name);
-
-}
-#endif
diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h
index d5471d6fa778..7f7e4a3f4394 100644
--- a/include/linux/timekeeping.h
+++ b/include/linux/timekeeping.h
@@ -222,6 +222,18 @@ extern bool timekeeping_rtc_skipresume(void);
extern void timekeeping_inject_sleeptime64(const struct timespec64 *delta);
+/*
+ * struct ktime_timestanps - Simultaneous mono/boot/real timestamps
+ * @mono: Monotonic timestamp
+ * @boot: Boottime timestamp
+ * @real: Realtime timestamp
+ */
+struct ktime_timestamps {
+ u64 mono;
+ u64 boot;
+ u64 real;
+};
+
/**
* struct system_time_snapshot - simultaneous raw/real time capture with
* counter value
@@ -280,6 +292,9 @@ extern int get_device_system_crosststamp(
*/
extern void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot);
+/* NMI safe mono/boot/realtime timestamps */
+extern void ktime_get_fast_timestamps(struct ktime_timestamps *snap);
+
/*
* Persistent clock related interfaces
*/
diff --git a/include/linux/timer.h b/include/linux/timer.h
index 07910ae5ddd9..d10bc7e73b41 100644
--- a/include/linux/timer.h
+++ b/include/linux/timer.h
@@ -67,6 +67,7 @@ struct timer_list {
#define TIMER_DEFERRABLE 0x00080000
#define TIMER_PINNED 0x00100000
#define TIMER_IRQSAFE 0x00200000
+#define TIMER_INIT_FLAGS (TIMER_DEFERRABLE | TIMER_PINNED |
TIMER_IRQSAFE)
#define TIMER_ARRAYSHIFT 22
#define TIMER_ARRAYMASK 0xFFC00000
diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index ca223a89530a..f4ace1bf8382 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -908,7 +908,7 @@ static int __init alarmtimer_init(void)
/* Initialize alarm bases */
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
- alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64,
+ alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64;
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
alarm_bases[ALARM_BOOTTIME].get_timespec = get_boottime_timespec;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 4c47f388a83f..ba7657685e22 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -54,6 +54,9 @@ static struct {
static struct timekeeper shadow_timekeeper;
+/* flag for if timekeeping is suspended */
+int __read_mostly timekeeping_suspended;
+
/**
* struct tk_fast - NMI safe timekeeper
* @seq: Sequence counter for protecting updates. The lowest bit
@@ -73,28 +76,42 @@ static u64 cycles_at_suspend;
static u64 dummy_clock_read(struct clocksource *cs)
{
- return cycles_at_suspend;
+ if (timekeeping_suspended)
+ return cycles_at_suspend;
+ return local_clock();
}
static struct clocksource dummy_clock = {
.read = dummy_clock_read,
};
+/*
+ * Boot time initialization which allows local_clock() to be utilized
+ * during early boot when clocksources are not available. local_clock()
+ * returns nanoseconds already so no conversion is required, hence mult=1
+ * and shift=0. When the first proper clocksource is installed then
+ * the fast time keepers are updated with the correct values.
+ */
+#define FAST_TK_INIT \
+ { \
+ .clock = &dummy_clock, \
+ .mask = CLOCKSOURCE_MASK(64), \
+ .mult = 1, \
+ .shift = 0, \
+ }
+
static struct tk_fast tk_fast_mono ____cacheline_aligned = {
.seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_mono.seq, &timekeeper_lock),
- .base[0] = { .clock = &dummy_clock, },
- .base[1] = { .clock = &dummy_clock, },
+ .base[0] = FAST_TK_INIT,
+ .base[1] = FAST_TK_INIT,
};
static struct tk_fast tk_fast_raw ____cacheline_aligned = {
.seq = SEQCNT_RAW_SPINLOCK_ZERO(tk_fast_raw.seq, &timekeeper_lock),
- .base[0] = { .clock = &dummy_clock, },
- .base[1] = { .clock = &dummy_clock, },
+ .base[0] = FAST_TK_INIT,
+ .base[1] = FAST_TK_INIT,
};
-/* flag for if timekeeping is suspended */
-int __read_mostly timekeeping_suspended;
-
static inline void tk_normalize_xtime(struct timekeeper *tk)
{
while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC <<
tk->tkr_mono.shift)) {
@@ -513,29 +530,29 @@ u64 notrace ktime_get_boot_fast_ns(void)
}
EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns);
-
/*
* See comment for __ktime_get_fast_ns() vs. timestamp ordering
*/
-static __always_inline u64 __ktime_get_real_fast_ns(struct tk_fast *tkf)
+static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64
*mono)
{
struct tk_read_base *tkr;
+ u64 basem, baser, delta;
unsigned int seq;
- u64 now;
do {
seq = raw_read_seqcount_latch(&tkf->seq);
tkr = tkf->base + (seq & 0x01);
- now = ktime_to_ns(tkr->base_real);
+ basem = ktime_to_ns(tkr->base);
+ baser = ktime_to_ns(tkr->base_real);
- now += timekeeping_delta_to_ns(tkr,
- clocksource_delta(
- tk_clock_read(tkr),
- tkr->cycle_last,
- tkr->mask));
+ delta = timekeeping_delta_to_ns(tkr,
+ clocksource_delta(tk_clock_read(tkr),
+ tkr->cycle_last, tkr->mask));
} while (read_seqcount_retry(&tkf->seq, seq));
- return now;
+ if (mono)
+ *mono = basem + delta;
+ return baser + delta;
}
/**
@@ -543,10 +560,64 @@ static __always_inline u64
__ktime_get_real_fast_ns(struct tk_fast *tkf)
*/
u64 ktime_get_real_fast_ns(void)
{
- return __ktime_get_real_fast_ns(&tk_fast_mono);
+ return __ktime_get_real_fast(&tk_fast_mono, NULL);
}
EXPORT_SYMBOL_GPL(ktime_get_real_fast_ns);
+/**
+ * ktime_get_fast_timestamps: - NMI safe timestamps
+ * @snapshot: Pointer to timestamp storage
+ *
+ * Stores clock monotonic, boottime and realtime timestamps.
+ *
+ * Boot time is a racy access on 32bit systems if the sleep time injection
+ * happens late during resume and not in timekeeping_resume(). That could
+ * be avoided by expanding struct tk_read_base with boot offset for 32bit
+ * and adding more overhead to the update. As this is a hard to observe
+ * once per resume event which can be filtered with reasonable effort using
+ * the accurate mono/real timestamps, it's probably not worth the trouble.
+ *
+ * Aside of that it might be possible on 32 and 64 bit to observe the
+ * following when the sleep time injection happens late:
+ *
+ * CPU 0 CPU 1
+ * timekeeping_resume()
+ * ktime_get_fast_timestamps()
+ * mono, real = __ktime_get_real_fast()
+ * inject_sleep_time()
+ * update boot offset
+ * boot = mono + bootoffset;
+ *
+ * That means that boot time already has the sleep time adjustment, but
+ * real time does not. On the next readout both are in sync again.
+ *
+ * Preventing this for 64bit is not really feasible without destroying the
+ * careful cache layout of the timekeeper because the sequence count and
+ * struct tk_read_base would then need two cache lines instead of one.
+ *
+ * Access to the time keeper clock source is disabled accross the innermost
+ * steps of suspend/resume. The accessors still work, but the timestamps
+ * are frozen until time keeping is resumed which happens very early.
+ *
+ * For regular suspend/resume there is no observable difference vs. sched
+ * clock, but it might affect some of the nasty low level debug printks.
+ *
+ * OTOH, access to sched clock is not guaranteed accross suspend/resume on
+ * all systems either so it depends on the hardware in use.
+ *
+ * If that turns out to be a real problem then this could be mitigated by
+ * using sched clock in a similar way as during early boot. But it's not as
+ * trivial as on early boot because it needs some careful protection
+ * against the clock monotonic timestamp jumping backwards on resume.
+ */
+void ktime_get_fast_timestamps(struct ktime_timestamps *snapshot)
+{
+ struct timekeeper *tk = &tk_core.timekeeper;
+
+ snapshot->real = __ktime_get_real_fast(&tk_fast_mono, &snapshot->mono);
+ snapshot->boot = snapshot->mono + ktime_to_ns(data_race(tk->offs_boot));
+}
+
/**
* halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource.
* @tk: Timekeeper to snapshot.
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index a16764b0116e..25e048d0e660 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -794,6 +794,8 @@ static void do_init_timer(struct timer_list *timer,
{
timer->entry.pprev = NULL;
timer->function = func;
+ if (WARN_ON_ONCE(flags & ~TIMER_INIT_FLAGS))
+ flags &= TIMER_INIT_FLAGS;
timer->flags = flags | raw_smp_processor_id();
lockdep_init_map(&timer->lockdep_map, name, key, 0);
}
