From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH] xen/arm: remove check for generic timer support for arm64 Date: Mon, 02 Jun 2014 12:13:40 +0100 Message-ID: <538C5C64.3080805@linaro.org> References: <1401698241-20722-1-git-send-email-vijay.kilari@gmail.com> <1401707388.11045.6.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1401707388.11045.6.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell , vijay.kilari@gmail.com Cc: Prasun.Kapoor@caviumnetworks.com, vijaya.kumar@caviumnetworks.com, xen-devel@lists.xen.org, stefano.stabellini@citrix.com, stefano.stabellini@eu.citrix.com List-Id: xen-devel@lists.xenproject.org On 06/02/2014 12:09 PM, Ian Campbell wrote: > On Mon, 2014-06-02 at 14:07 +0530, vijay.kilari@gmail.com wrote: >> From: Vijaya Kumar K >> >> arm64 always supports generic timer. So check is not required >> for arm64. For platforms which supports only aarch64 mode this >> check always passes and panics > > Ah, because the relevant feature flag/register is 32-bit only. > > I'd prefer to see this done in the cpufeature header as: > #ifdef CONFIG_ARM_32 > #define cpu_has_gentimer (boot_cpu_feature32(gentimer) == 1) > #else > #define cpu_has_gentimer (1) > #endif > rather than adding #ifdef to the common code. Likewise for any similar > "always on for aarch64" features. AFAIU, the feature flag exists on ARMv8 platform with aarch32 support. So an ifdef may not be the correct solution here. Regards, -- Julien Grall