* [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
@ 2014-11-07 0:21 Anatol Pomozov
2014-11-07 0:25 ` Anatol Pomozov
0 siblings, 1 reply; 6+ messages in thread
From: Anatol Pomozov @ 2014-11-07 0:21 UTC (permalink / raw)
To: marc.zyngier, mark.rutland
Cc: lorenzo.pieralisi, linux-kernel, Anatol Pomozov
This allows to port code that needs register_persistent_clock() to arm64
Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
---
arch/arm64/include/asm/time.h | 17 +++++++++++++++++
arch/arm64/kernel/time.c | 37 +++++++++++++++++++++++++++++++++++++
2 files changed, 54 insertions(+)
create mode 100644 arch/arm64/include/asm/time.h
diff --git a/arch/arm64/include/asm/time.h b/arch/arm64/include/asm/time.h
new file mode 100644
index 0000000..28015b8
--- /dev/null
+++ b/arch/arm64/include/asm/time.h
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2004 MontaVista Software, Inc.
+ * Copyright (C) 2014 The Chromium OS Authors.
+ *
+ * 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.
+ */
+#ifndef __ASM_TIME_H
+#define __ASM_TIME_H
+
+struct timespec;
+typedef void (*clock_access_fn)(struct timespec *);
+extern int register_persistent_clock(clock_access_fn read_boot,
+ clock_access_fn read_persistent);
+
+#endif
diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
index 1a7125c..71a907e 100644
--- a/arch/arm64/kernel/time.c
+++ b/arch/arm64/kernel/time.c
@@ -40,6 +40,7 @@
#include <asm/thread_info.h>
#include <asm/stacktrace.h>
+#include <asm/time.h>
#ifdef CONFIG_SMP
unsigned long profile_pc(struct pt_regs *regs)
@@ -79,3 +80,39 @@ void __init time_init(void)
/* Calibrate the delay loop directly */
lpj_fine = arch_timer_rate / HZ;
}
+
+static void dummy_clock_access(struct timespec *ts)
+{
+ ts->tv_sec = 0;
+ ts->tv_nsec = 0;
+}
+
+static clock_access_fn __read_persistent_clock = dummy_clock_access;
+static clock_access_fn __read_boot_clock = dummy_clock_access;
+
+void read_persistent_clock(struct timespec *ts)
+{
+ __read_persistent_clock(ts);
+}
+
+void read_boot_clock(struct timespec *ts)
+{
+ __read_boot_clock(ts);
+}
+
+int __init register_persistent_clock(clock_access_fn read_boot,
+ clock_access_fn read_persistent)
+{
+ /* Only allow the clockaccess functions to be registered once */
+ if (__read_persistent_clock == dummy_clock_access &&
+ __read_boot_clock == dummy_clock_access) {
+ if (read_boot)
+ __read_boot_clock = read_boot;
+ if (read_persistent)
+ __read_persistent_clock = read_persistent;
+
+ return 0;
+ }
+
+ return -EINVAL;
+}
--
2.1.0.rc2.206.gedb03e5
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
2014-11-07 0:21 [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree Anatol Pomozov
@ 2014-11-07 0:25 ` Anatol Pomozov
2014-11-07 4:16 ` Stephen Warren
0 siblings, 1 reply; 6+ messages in thread
From: Anatol Pomozov @ 2014-11-07 0:25 UTC (permalink / raw)
To: Marc Zyngier, mark.rutland, Stephen Warren
Cc: Lorenzo Pieralisi, LKML, Anatol Pomozov
+Stephen
This patch is for tegra20_timer that uses register_persistent_clock().
I did not find any way to share the same arch code for arm/arm64.
Actually this register_persistent_clock() does not look arm specific
at all. Would it be better to move it somewhere outside of arch/?
On Thu, Nov 6, 2014 at 4:21 PM, Anatol Pomozov <anatol.pomozov@gmail.com> wrote:
> This allows to port code that needs register_persistent_clock() to arm64
>
> Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
> ---
> arch/arm64/include/asm/time.h | 17 +++++++++++++++++
> arch/arm64/kernel/time.c | 37 +++++++++++++++++++++++++++++++++++++
> 2 files changed, 54 insertions(+)
> create mode 100644 arch/arm64/include/asm/time.h
>
> diff --git a/arch/arm64/include/asm/time.h b/arch/arm64/include/asm/time.h
> new file mode 100644
> index 0000000..28015b8
> --- /dev/null
> +++ b/arch/arm64/include/asm/time.h
> @@ -0,0 +1,17 @@
> +/*
> + * Copyright (C) 2004 MontaVista Software, Inc.
> + * Copyright (C) 2014 The Chromium OS Authors.
> + *
> + * 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.
> + */
> +#ifndef __ASM_TIME_H
> +#define __ASM_TIME_H
> +
> +struct timespec;
> +typedef void (*clock_access_fn)(struct timespec *);
> +extern int register_persistent_clock(clock_access_fn read_boot,
> + clock_access_fn read_persistent);
> +
> +#endif
> diff --git a/arch/arm64/kernel/time.c b/arch/arm64/kernel/time.c
> index 1a7125c..71a907e 100644
> --- a/arch/arm64/kernel/time.c
> +++ b/arch/arm64/kernel/time.c
> @@ -40,6 +40,7 @@
>
> #include <asm/thread_info.h>
> #include <asm/stacktrace.h>
> +#include <asm/time.h>
>
> #ifdef CONFIG_SMP
> unsigned long profile_pc(struct pt_regs *regs)
> @@ -79,3 +80,39 @@ void __init time_init(void)
> /* Calibrate the delay loop directly */
> lpj_fine = arch_timer_rate / HZ;
> }
> +
> +static void dummy_clock_access(struct timespec *ts)
> +{
> + ts->tv_sec = 0;
> + ts->tv_nsec = 0;
> +}
> +
> +static clock_access_fn __read_persistent_clock = dummy_clock_access;
> +static clock_access_fn __read_boot_clock = dummy_clock_access;
> +
> +void read_persistent_clock(struct timespec *ts)
> +{
> + __read_persistent_clock(ts);
> +}
> +
> +void read_boot_clock(struct timespec *ts)
> +{
> + __read_boot_clock(ts);
> +}
> +
> +int __init register_persistent_clock(clock_access_fn read_boot,
> + clock_access_fn read_persistent)
> +{
> + /* Only allow the clockaccess functions to be registered once */
> + if (__read_persistent_clock == dummy_clock_access &&
> + __read_boot_clock == dummy_clock_access) {
> + if (read_boot)
> + __read_boot_clock = read_boot;
> + if (read_persistent)
> + __read_persistent_clock = read_persistent;
> +
> + return 0;
> + }
> +
> + return -EINVAL;
> +}
> --
> 2.1.0.rc2.206.gedb03e5
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
2014-11-07 0:25 ` Anatol Pomozov
@ 2014-11-07 4:16 ` Stephen Warren
2014-11-07 10:40 ` Mark Rutland
0 siblings, 1 reply; 6+ messages in thread
From: Stephen Warren @ 2014-11-07 4:16 UTC (permalink / raw)
To: Anatol Pomozov
Cc: Marc Zyngier, mark.rutland, Lorenzo Pieralisi, LKML,
linux-tegra@vger.kernel.org
On 11/06/2014 05:25 PM, Anatol Pomozov wrote:
> +Stephen
>
> This patch is for tegra20_timer that uses register_persistent_clock().
> I did not find any way to share the same arch code for arm/arm64.
>
> Actually this register_persistent_clock() does not look arm specific
> at all. Would it be better to move it somewhere outside of arch/?
No CC to linux-tegra@ or the other Tegra maintainers?
Yes, I think it'd be best not to have arch-specific APIs, or cut/paste
the same code into multiple places.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
2014-11-07 4:16 ` Stephen Warren
@ 2014-11-07 10:40 ` Mark Rutland
2014-11-07 16:24 ` Anatol Pomozov
0 siblings, 1 reply; 6+ messages in thread
From: Mark Rutland @ 2014-11-07 10:40 UTC (permalink / raw)
To: Stephen Warren
Cc: Anatol Pomozov, Marc Zyngier, Lorenzo Pieralisi, LKML,
linux-tegra@vger.kernel.org
On Fri, Nov 07, 2014 at 04:16:03AM +0000, Stephen Warren wrote:
> On 11/06/2014 05:25 PM, Anatol Pomozov wrote:
> > +Stephen
> >
> > This patch is for tegra20_timer that uses register_persistent_clock().
> > I did not find any way to share the same arch code for arm/arm64.
> >
> > Actually this register_persistent_clock() does not look arm specific
> > at all. Would it be better to move it somewhere outside of arch/?
>
> No CC to linux-tegra@ or the other Tegra maintainers?
>
> Yes, I think it'd be best not to have arch-specific APIs, or cut/paste
> the same code into multiple places.
Agreed. This looks in no way architecture specific, and having this in
common code would be preferable to copying.
Mark.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
2014-11-07 10:40 ` Mark Rutland
@ 2014-11-07 16:24 ` Anatol Pomozov
2014-11-07 16:38 ` Mark Rutland
0 siblings, 1 reply; 6+ messages in thread
From: Anatol Pomozov @ 2014-11-07 16:24 UTC (permalink / raw)
To: Mark Rutland
Cc: Stephen Warren, Marc Zyngier, Lorenzo Pieralisi, LKML,
linux-tegra@vger.kernel.org
Hi
On Fri, Nov 7, 2014 at 2:40 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> On Fri, Nov 07, 2014 at 04:16:03AM +0000, Stephen Warren wrote:
>> On 11/06/2014 05:25 PM, Anatol Pomozov wrote:
>> > +Stephen
>> >
>> > This patch is for tegra20_timer that uses register_persistent_clock().
>> > I did not find any way to share the same arch code for arm/arm64.
>> >
>> > Actually this register_persistent_clock() does not look arm specific
>> > at all. Would it be better to move it somewhere outside of arch/?
>>
>> No CC to linux-tegra@ or the other Tegra maintainers?
>>
>> Yes, I think it'd be best not to have arch-specific APIs, or cut/paste
>> the same code into multiple places.
>
> Agreed. This looks in no way architecture specific, and having this in
> common code would be preferable to copying.
Where the code common for arm and arm64 should go?
drivers/???/arm_timekeeping.c ?
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree
2014-11-07 16:24 ` Anatol Pomozov
@ 2014-11-07 16:38 ` Mark Rutland
0 siblings, 0 replies; 6+ messages in thread
From: Mark Rutland @ 2014-11-07 16:38 UTC (permalink / raw)
To: Anatol Pomozov
Cc: Stephen Warren, Marc Zyngier, Lorenzo Pieralisi, LKML,
linux-tegra@vger.kernel.org
On Fri, Nov 07, 2014 at 04:24:19PM +0000, Anatol Pomozov wrote:
> Hi
>
> On Fri, Nov 7, 2014 at 2:40 AM, Mark Rutland <mark.rutland@arm.com> wrote:
> > On Fri, Nov 07, 2014 at 04:16:03AM +0000, Stephen Warren wrote:
> >> On 11/06/2014 05:25 PM, Anatol Pomozov wrote:
> >> > +Stephen
> >> >
> >> > This patch is for tegra20_timer that uses register_persistent_clock().
> >> > I did not find any way to share the same arch code for arm/arm64.
> >> >
> >> > Actually this register_persistent_clock() does not look arm specific
> >> > at all. Would it be better to move it somewhere outside of arch/?
> >>
> >> No CC to linux-tegra@ or the other Tegra maintainers?
> >>
> >> Yes, I think it'd be best not to have arch-specific APIs, or cut/paste
> >> the same code into multiple places.
> >
> > Agreed. This looks in no way architecture specific, and having this in
> > common code would be preferable to copying.
>
> Where the code common for arm and arm64 should go?
> drivers/???/arm_timekeeping.c ?
I'd argue that this is in no way specific to ARM, and the current weak
functions live in kernel/time/timekeeping.c, so this should too.
Thanks,
Mark.
^ permalink raw reply [flat|nested] 6+ messages in thread
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2014-11-07 0:21 [PATCH] arm64: kernel: Copy register_persistent_clock() to arm64 source subtree Anatol Pomozov
2014-11-07 0:25 ` Anatol Pomozov
2014-11-07 4:16 ` Stephen Warren
2014-11-07 10:40 ` Mark Rutland
2014-11-07 16:24 ` Anatol Pomozov
2014-11-07 16:38 ` Mark Rutland
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