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From: Arnd Bergmann <arnd@arndb.de>
To: Catalin Marinas <catalin.marinas@arm.com>
Cc: John Stultz <john.stultz@linaro.org>,
	Marc Zyngier <Marc.Zyngier@arm.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Deepak Saxena <dsaxena@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Linus Walleij <linus.ml.walleij@gmail.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Will Deacon <Will.Deacon@arm.com>,
	Mike Turquette <mike.turquette@linaro.org>,
	Marc Zyngier <maz@misterjones.org>
Subject: Re: [PATCH 33/36] AArch64: Generic timers support
Date: Fri, 13 Jul 2012 16:32:31 +0000	[thread overview]
Message-ID: <201207131632.31548.arnd@arndb.de> (raw)
In-Reply-To: <20120713160233.GB5544@arm.com>

On Friday 13 July 2012, Catalin Marinas wrote:
> > Architectures that always have a working clock source would then just
> > not include the timex.h header and #define ACT_HZ HZ in common code.
> 
> Would something like below be enough?
> 
> Also, are there any implications if we boot with clocksource=jiffies?
> 
> --- a/include/linux/jiffies.h
> +++ b/include/linux/jiffies.h
> @@ -55,7 +55,11 @@
>                               + ((((NOM) % (DEN)) << (LSH)) + (DEN) / 2) / (DEN))
>  
>  /* HZ is the requested value. ACTHZ is actual HZ ("<< 8" is for accuracy) */
> +#ifdef CLOCK_TICK_RATE
>  #define ACTHZ (SH_DIV (CLOCK_TICK_RATE, LATCH, 8))
> +#else
> +#define ACTHZ (HZ << 8)
> +#endif
>  
>  /* TICK_NSEC is the time between ticks in nsec assuming real ACTHZ */
>  #define TICK_NSEC (SH_DIV (1000000UL * 1000, ACTHZ, 8))
> 

I think that's a very good step in the right direction, yes.

It does not let us get rid of the asm/timex.h file, but that's actually
a separate problem. It also wouldn't hurt to put the LATCH definition
in the same #ifdef.

Acked-by: Arnd Bergmann <arnd@arndb.de>

	Arnd


  reply	other threads:[~2012-07-13 16:32 UTC|newest]

Thread overview: 182+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-07-06 21:05 [PATCH 00/36] AArch64 Linux kernel port Catalin Marinas
2012-07-06 21:05 ` [PATCH 01/36] atomic64_test: Simplify the #ifdef for atomic64_dec_if_positive() test Catalin Marinas
2012-07-18  4:33   ` Benjamin Herrenschmidt
2012-07-18  9:06     ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 02/36] ipc: Add COMPAT_SHMLBA support Catalin Marinas
2012-07-18  5:53   ` Jon Masters
2012-07-18  9:03     ` Will Deacon
2012-07-06 21:05 ` [PATCH 03/36] ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC Catalin Marinas
2012-07-06 21:05 ` [PATCH 04/36] ipc: compat: use signed size_t types for msgsnd and msgrcv Catalin Marinas
2012-07-06 21:05 ` [PATCH 05/36] fs: Build sys_stat64() and friends if __ARCH_WANT_COMPAT_STAT64 Catalin Marinas
2012-07-06 21:05 ` [PATCH 06/36] fdt: Add generic dt_memblock_reserve() function Catalin Marinas
2012-07-07 21:18   ` Rob Herring
2012-07-08  9:43     ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 07/36] AArch64: Assembly macros and definitions Catalin Marinas
2012-07-07  5:57   ` Greg KH
2012-07-08  9:23     ` Catalin Marinas
2012-07-20 14:22   ` [07/36] " Christopher Covington
2012-07-24 16:40     ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 08/36] AArch64: Kernel booting and initialisation Catalin Marinas
2012-07-06 21:32   ` Stephen Warren
2012-07-08  9:18     ` Catalin Marinas
2012-07-23 17:48       ` Stephen Warren
2012-07-23 17:58         ` Catalin Marinas
2012-07-18  6:57   ` Jon Masters
2012-07-18  9:07     ` Will Deacon
2012-07-20  7:11       ` Jon Masters
2012-07-19 17:31     ` Christopher Covington
2012-07-20  7:10       ` Jon Masters
2012-07-20  8:28         ` Arnd Bergmann
2012-07-20 10:52           ` Catalin Marinas
2012-07-20 12:32             ` Geert Uytterhoeven
2012-07-20 13:16               ` Catalin Marinas
2012-07-20 13:47         ` Christopher Covington
2012-07-20 13:52           ` Catalin Marinas
2012-07-20 13:48       ` Catalin Marinas
2012-07-20 14:53         ` Christopher Covington
2012-07-23 20:52   ` [08/36] " Christopher Covington
2012-07-24 16:24     ` Catalin Marinas
2012-07-24 18:53       ` Arnd Bergmann
2012-07-24 23:20         ` Frank Rowand
2012-07-25  8:34         ` Catalin Marinas
2012-07-24 19:42   ` Christopher Covington
2012-07-25  8:47     ` Catalin Marinas
2012-07-25 13:39       ` Christopher Covington
2012-07-06 21:05 ` [PATCH 09/36] AArch64: Exception handling Catalin Marinas
2012-08-09 17:05   ` [09/36] " Christopher Covington
2012-08-09 17:23     ` Catalin Marinas
2012-08-09 19:19       ` Christopher Covington
2012-07-06 21:05 ` [PATCH 10/36] AArch64: MMU definitions Catalin Marinas
2012-10-02  0:43   ` Jon Masters
2012-10-02 15:39     ` Catalin Marinas
2012-07-06 21:05 ` [PATCH 11/36] AArch64: MMU initialisation Catalin Marinas
2012-07-06 21:05 ` [PATCH 12/36] AArch64: MMU fault handling and page table management Catalin Marinas
2012-07-06 21:05 ` [PATCH 13/36] AArch64: Process management Catalin Marinas
2012-07-06 21:05 ` [PATCH 14/36] AArch64: CPU support Catalin Marinas
2012-07-06 21:05 ` [PATCH 15/36] AArch64: Cache maintenance routines Catalin Marinas
2012-07-06 21:05 ` [PATCH 16/36] AArch64: TLB maintenance functionality Catalin Marinas
2012-07-06 21:05 ` [PATCH 17/36] AArch64: IRQ handling Catalin Marinas
2012-07-06 21:05 ` [PATCH 18/36] AArch64: Atomic operations Catalin Marinas
2012-07-06 21:06 ` [PATCH 19/36] AArch64: Device specific operations Catalin Marinas
2012-07-06 21:06 ` [PATCH 20/36] AArch64: DMA mapping API Catalin Marinas
2012-07-06 21:06 ` [PATCH 21/36] AArch64: SMP support Catalin Marinas
2012-07-06 21:06 ` [PATCH 22/36] AArch64: ELF definitions Catalin Marinas
2012-07-06 21:06 ` [PATCH 23/36] AArch64: System calls handling Catalin Marinas
2012-07-06 21:06 ` [PATCH 24/36] AArch64: VDSO support Catalin Marinas
2012-07-06 21:06 ` [PATCH 25/36] AArch64: Signal handling support Catalin Marinas
2012-07-06 21:06 ` [PATCH 26/36] AArch64: User access library functions Catalin Marinas
2012-07-06 21:06 ` [PATCH 27/36] AArch64: 32-bit (compat) applications support Catalin Marinas
2012-07-06 21:06 ` [PATCH 28/36] AArch64: Floating point and SIMD Catalin Marinas
2012-07-06 21:06 ` [PATCH 29/36] AArch64: Debugging support Catalin Marinas
2012-07-06 21:06 ` [PATCH 30/36] AArch64: Performance counters support Catalin Marinas
2012-07-06 21:06 ` [PATCH 31/36] AArch64: Miscellaneous library functions Catalin Marinas
2012-07-06 21:06 ` [PATCH 32/36] AArch64: Loadable modules Catalin Marinas
2012-07-06 21:06 ` [PATCH 33/36] AArch64: Generic timers support Catalin Marinas
2012-07-12  0:18   ` Linus Walleij
2012-07-12 10:09     ` Marc Zyngier
2012-07-12 10:56       ` Linus Walleij
2012-07-12 16:57         ` John Stultz
2012-07-12 17:31           ` Marc Zyngier
2012-07-12 17:39             ` John Stultz
2012-07-13 12:40               ` Arnd Bergmann
2012-07-13 16:02                 ` Catalin Marinas
2012-07-13 16:32                   ` Arnd Bergmann [this message]
2012-07-13 18:30                   ` John Stultz
2012-07-06 21:06 ` [PATCH 34/36] AArch64: Miscellaneous header files Catalin Marinas
2012-07-06 21:06 ` [PATCH 35/36] AArch64: Build infrastructure Catalin Marinas
2012-07-06 21:06 ` [PATCH 36/36] AArch64: MAINTAINERS update Catalin Marinas
2012-08-10 16:24   ` [36/36] " Christopher Covington
2012-07-06 22:58 ` [PATCH 00/36] AArch64 Linux kernel port Alan Cox
2012-07-07 21:30   ` Arnd Bergmann
2012-07-07 23:14   ` Catalin Marinas
2012-07-07 23:29     ` Alan Cox
2012-07-09 11:35       ` Catalin Marinas
2012-07-09 13:51         ` Alan Cox
2012-07-09 15:32           ` Arnd Bergmann
2012-07-09 15:49             ` Alan Cox
2012-07-09 16:02             ` Catalin Marinas
2012-07-09 16:33               ` Arnd Bergmann
2012-07-07  3:29 ` Matthew Garrett
2012-07-09 12:32   ` Mark Brown
2012-07-09 13:06     ` Matthew Garrett
2012-07-09 13:56       ` Mark Brown
2012-07-09 14:02         ` Matthew Garrett
2012-07-09 15:46           ` Mark Brown
2012-07-07  3:53 ` Olof Johansson
2012-07-07 19:27   ` Arnd Bergmann
2012-07-07 23:45     ` Jan Engelhardt
2012-07-08  5:05       ` Henrique de Moraes Holschuh
2012-07-08 20:28         ` Jan Engelhardt
2012-07-08  7:54     ` Jon Masters
2012-07-08 11:17       ` Dr. David Alan Gilbert
2012-07-08 18:13         ` Jon Masters
2012-07-08 18:31       ` Jon Masters
2012-07-08 22:24         ` Dennis Gilmore
2012-07-09  2:01           ` Jon Masters
2012-07-09  8:57             ` Catalin Marinas
2012-07-09 13:33             ` Geert Uytterhoeven
2012-07-08 20:31       ` Jan Engelhardt
2012-07-08 23:32         ` Jon Masters
2012-07-10  7:10     ` Ingo Molnar
2012-07-10 10:10       ` Catalin Marinas
2012-07-10 15:33         ` Alan Cox
2012-07-10 16:52           ` Arnd Bergmann
2012-07-10 20:35             ` Ingo Molnar
2012-07-10 21:19               ` Arnd Bergmann
2012-07-10 21:48                 ` Catalin Marinas
2012-07-11  8:20                 ` Ingo Molnar
2012-07-11 11:30                 ` Alan Cox
2012-07-10 21:44               ` Catalin Marinas
2012-07-11  8:55                 ` Catalin Marinas
2012-07-11  5:26             ` Rusty Russell
2012-07-11 10:53               ` Catalin Marinas
2012-07-12  2:08                 ` Rusty Russell
2012-07-10 16:57           ` Catalin Marinas
2012-07-10 16:52         ` Dennis Gilmore
2012-07-10 17:14         ` Joe Perches
2012-07-10 18:01           ` Jan Ceuleers
2012-07-10 18:05             ` richard -rw- weinberger
2012-07-10 20:16           ` Alexander Holler
2012-07-14 22:16             ` Jon Masters
2012-07-10 22:08         ` Chris Adams
2012-07-14  9:30         ` Pavel Machek
2012-07-15 12:16           ` Catalin Marinas
2012-07-15 19:43             ` Arnd Bergmann
2012-07-15 21:33               ` Catalin Marinas
2012-07-16 12:16                 ` Pavel Machek
2012-07-17  7:05                   ` Jon Masters
2012-07-17  8:02                     ` Arnd Bergmann
2012-07-17  9:50                       ` Alan Cox
2012-07-18  2:36                         ` Jon Masters
2012-07-17 10:45                   ` Catalin Marinas
2012-07-16  9:26               ` Geert Uytterhoeven
2012-07-17  6:53               ` Christoph Hellwig
2012-07-17  8:07                 ` Arnd Bergmann
2012-07-16  8:24             ` Avi Kivity
2012-07-17  7:09               ` Jon Masters
2012-07-17  8:37               ` Catalin Marinas
2012-07-15 23:21         ` Måns Rullgård
2012-07-15 23:53           ` Linus Torvalds
2012-07-17 22:18             ` Catalin Marinas
2012-07-17 22:35               ` Joe Perches
2012-07-18  2:33                 ` Jon Masters
2012-07-18 15:27                   ` Dennis Gilmore
2012-07-18 17:14                     ` Catalin Marinas
2012-07-18 17:25                       ` Måns Rullgård
2012-07-18 19:35                       ` Jon Masters
2012-07-18 19:55                         ` Linus Torvalds
2012-07-19 14:16     ` Guillem Jover
2012-07-07 23:42   ` Jan Engelhardt
2012-07-08 10:18   ` Catalin Marinas
2012-07-09 12:31     ` Jan Engelhardt
2012-07-07  9:30 ` Mikael Pettersson
2012-07-07 19:21   ` Kirill A. Shutemov
2012-07-10 10:12   ` Catalin Marinas
2012-07-14  9:35     ` Pavel Machek
2012-07-15 11:36       ` Catalin Marinas
2012-07-16 16:19         ` Pavel Machek
2012-07-16 19:45           ` Arnd Bergmann
2012-07-16 19:47           ` Måns Rullgård
2012-07-18  5:35 ` Jon Masters
2012-07-18  9:13   ` Catalin Marinas
2012-07-26 11:59 ` Catalin Marinas
     [not found] <jknWN-4WG-3@gated-at.bofh.it>
     [not found] ` <jkulA-O3-3@gated-at.bofh.it>
     [not found]   ` <jkIRz-2Hu-11@gated-at.bofh.it>

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