[PATCH] arm64: Correct the stated event stream frequency

[PATCH] arm64: Correct the stated event stream frequency

[Catalin Marinas]

It should be 10KHz, matching the ARCH_TIMER_EVT_STREAM_PERIOD_US of
100us.

Fixes: 611a7bc74ed2 ("arm64: docs: describe ELF hwcaps")
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
---
 Documentation/arm64/elf_hwcaps.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst
index 87821662eeb2..ec1a5a63c1d0 100644
--- a/Documentation/arm64/elf_hwcaps.rst
+++ b/Documentation/arm64/elf_hwcaps.rst
@@ -74,7 +74,7 @@ HWCAP_ASIMD
 
 HWCAP_EVTSTRM
     The generic timer is configured to generate events at a frequency of
-    approximately 100KHz.
+    approximately 10KHz.
 
 HWCAP_AES
     Functionality implied by ID_AA64ISAR0_EL1.AES == 0b0001.

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Re: [PATCH] arm64: Correct the stated event stream frequency

[Mark Rutland]

On Wed, May 05, 2021 at 02:28:45PM +0100, Catalin Marinas wrote:
> It should be 10KHz, matching the ARCH_TIMER_EVT_STREAM_PERIOD_US of
> 100us.
> 
> Fixes: 611a7bc74ed2 ("arm64: docs: describe ELF hwcaps")
> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>

It might be worth being more explicit in the commit message, to make it
clear that this is just a documentation bug. e.g.

| In 2013 we introduced a (roughly) 10KHz event stream in commit:
| 
|   037f637767a82907 ("drivers: clocksource: add support for ARM architected timer event stream")
| 
| ... but in 2017 when we documented this in commit:
| 
|   611a7bc74ed2dcba ("arm64: docs: describe ELF hwcaps")
| 
| ... we erroneously stated that the frequency was roughly 100KHz.
| 
| This patch corrects the documentation.

Either way:

Acked-by: Mark Rutland <mark.rutland@arm.com>

Mark.

> ---
>  Documentation/arm64/elf_hwcaps.rst | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst
> index 87821662eeb2..ec1a5a63c1d0 100644
> --- a/Documentation/arm64/elf_hwcaps.rst
> +++ b/Documentation/arm64/elf_hwcaps.rst
> @@ -74,7 +74,7 @@ HWCAP_ASIMD
>  
>  HWCAP_EVTSTRM
>      The generic timer is configured to generate events at a frequency of
> -    approximately 100KHz.
> +    approximately 10KHz.
>  
>  HWCAP_AES
>      Functionality implied by ID_AA64ISAR0_EL1.AES == 0b0001.

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Re: [PATCH] arm64: Correct the stated event stream frequency

[Catalin Marinas]

On Wed, 5 May 2021 14:28:45 +0100, Catalin Marinas wrote:
> It should be 10KHz, matching the ARCH_TIMER_EVT_STREAM_PERIOD_US of
> 100us.

Applied to arm64 (for-next/core), thanks!

[1/1] arm64: Correct the stated event stream frequency
      https://git.kernel.org/arm64/c/5d8505fd039c

-- 
Catalin


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