From: Stefano Stabellini <sstabellini@kernel.org>
To: Julien Grall <julien.grall@arm.com>
Cc: andre.przywara@arm.com, sstabellini@kernel.org,
steve.capper@arm.com, wei.chen@arm.com, xen-devel@lists.xen.org
Subject: Re: [PATCH v3 10/16] xen/arm: cpufeature: Provide an helper to check if a capability is supported
Date: Wed, 22 Jun 2016 10:59:31 +0100 (BST) [thread overview]
Message-ID: <alpine.DEB.2.10.1606221055580.2575@sstabellini-ThinkPad-X260> (raw)
In-Reply-To: <1465315583-1278-11-git-send-email-julien.grall@arm.com>
On Tue, 7 Jun 2016, Julien Grall wrote:
> The CPU capabilities will be set depending on the value found in the CPU
> registers. This patch provides a generic to go through a set of capabilities
> and find which one should be enabled.
>
> The parameter "info" is used to display the kind of capability updated (e.g
> workaround, feature...).
>
> Signed-off-by: Julien Grall <julien.grall@arm.com>
>
> ---
> Changes in v3:
> - Patch added. The code was previously part of "Detect
> silicon...".
> ---
> xen/arch/arm/cpufeature.c | 16 ++++++++++++++++
> xen/include/asm-arm/cpufeature.h | 9 +++++++++
> 2 files changed, 25 insertions(+)
>
> diff --git a/xen/arch/arm/cpufeature.c b/xen/arch/arm/cpufeature.c
> index 7a1b56b..088625b 100644
> --- a/xen/arch/arm/cpufeature.c
> +++ b/xen/arch/arm/cpufeature.c
> @@ -24,6 +24,22 @@
>
> DECLARE_BITMAP(cpu_hwcaps, ARM_NCAPS);
>
> +void update_cpu_capabilities(const struct arm_cpu_capabilities *caps,
> + const char *info)
> +{
> + int i;
> +
> + for ( i = 0; caps[i].matches; i++ )
> + {
> + if ( !caps[i].matches(&caps[i]) )
> + continue;
> +
> + if ( !cpus_have_cap(caps[i].capability) && caps[i].desc )
> + printk(XENLOG_INFO "%s: %s\n", info, caps[i].desc);
The patch is OK. I still have the same comment as before: if an info
parameter is passed to this function with a string, then I think the
string should contain some useful information. Not a generic message.
I would just do:
printk(XENLOG_INFO "enable workaround for: %s\n", caps[i].desc);
If one day we need to change the message depending on the caller, then
that day we'll add a parameter to update_cpu_capabilities.
> + cpus_set_cap(caps[i].capability);
> + }
> +}
> +
> /*
> * Local variables:
> * mode: C
> diff --git a/xen/include/asm-arm/cpufeature.h b/xen/include/asm-arm/cpufeature.h
> index 2bebad1..be2414c 100644
> --- a/xen/include/asm-arm/cpufeature.h
> +++ b/xen/include/asm-arm/cpufeature.h
> @@ -62,6 +62,15 @@ static inline void cpus_set_cap(unsigned int num)
> __set_bit(num, cpu_hwcaps);
> }
>
> +struct arm_cpu_capabilities {
> + const char *desc;
> + u16 capability;
> + bool_t (*matches)(const struct arm_cpu_capabilities *);
> +};
> +
> +void update_cpu_capabilities(const struct arm_cpu_capabilities *caps,
> + const char *info);
> +
> #endif /* __ASSEMBLY__ */
>
> #endif
> --
> 1.9.1
>
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2016-06-22 9:59 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-07 16:06 [PATCH v3 00/16] xen/arm: Introduce alternative runtime patching for ARM64 Julien Grall
2016-06-07 16:06 ` [PATCH v3 01/16] xen/arm: Makefile: Sort the entries alphabetically Julien Grall
2016-06-07 16:06 ` [PATCH v3 02/16] xen/arm: Include the header asm-arm/system.h in asm-arm/page.h Julien Grall
2016-06-07 16:06 ` [PATCH v3 03/16] xen/arm: Add macros to handle the MIDR Julien Grall
2016-06-07 16:06 ` [PATCH v3 04/16] xen/arm: Add cpu_hwcap bitmap Julien Grall
2016-06-07 16:06 ` [PATCH v3 05/16] xen/arm64: Add an helper to invalidate all instruction caches Julien Grall
2016-06-07 16:06 ` [PATCH v3 06/16] xen/arm: arm64: Move the define BRK_BUG_FRAME into a separate header Julien Grall
2016-06-07 16:06 ` [PATCH v3 07/16] xen/arm: arm64: Reserve a brk immediate to fault on purpose Julien Grall
2016-06-07 16:06 ` [PATCH v3 08/16] xen/arm: arm64: Add helpers to decode and encode branch instructions Julien Grall
2016-06-07 16:06 ` [PATCH v3 09/16] xen/arm: Introduce alternative runtime patching Julien Grall
2016-06-07 17:24 ` Konrad Rzeszutek Wilk
2016-06-08 9:39 ` Julien Grall
2016-06-08 18:17 ` Konrad Rzeszutek Wilk
2016-06-08 18:22 ` Julien Grall
2016-06-08 18:35 ` Konrad Rzeszutek Wilk
2016-06-09 13:33 ` Julien Grall
2016-06-07 16:06 ` [PATCH v3 10/16] xen/arm: cpufeature: Provide an helper to check if a capability is supported Julien Grall
2016-06-22 9:59 ` Stefano Stabellini [this message]
2016-06-22 10:09 ` Julien Grall
2016-06-22 10:14 ` Stefano Stabellini
2016-06-07 16:06 ` [PATCH v3 11/16] xen/arm: Detect silicon revision and set cap bits accordingly Julien Grall
2016-06-22 10:00 ` Stefano Stabellini
2016-06-07 16:06 ` [PATCH v3 12/16] xen/arm: Document the errata implemented in Xen Julien Grall
2016-06-22 10:03 ` Stefano Stabellini
2016-06-07 16:06 ` [PATCH v3 13/16] xen/arm: arm64: Add Cortex-A53 cache errata workaround Julien Grall
2016-06-22 10:04 ` Stefano Stabellini
2016-06-07 16:06 ` [PATCH v3 14/16] xen/arm: arm64: Add cortex-A57 erratum 832075 workaround Julien Grall
2016-06-22 10:10 ` Stefano Stabellini
2016-06-07 16:06 ` [PATCH v3 15/16] xen/arm: traps: Don't inject a fault if the translation VA -> IPA fails Julien Grall
2016-06-07 16:06 ` [PATCH v3 16/16] xen/arm: arm64: Document Cortex-A57 erratum 834220 Julien Grall
2016-06-14 12:15 ` Julien Grall
2016-06-22 10:08 ` Stefano Stabellini
2016-06-22 10:18 ` Julien Grall
2016-06-22 10:37 ` Stefano Stabellini
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.DEB.2.10.1606221055580.2575@sstabellini-ThinkPad-X260 \
--to=sstabellini@kernel.org \
--cc=andre.przywara@arm.com \
--cc=julien.grall@arm.com \
--cc=steve.capper@arm.com \
--cc=wei.chen@arm.com \
--cc=xen-devel@lists.xen.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).