Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755618Ab1BXTBj (ORCPT ); Thu, 24 Feb 2011 14:01:39 -0500 Received: from www.tglx.de ([62.245.132.106]:42245 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754399Ab1BXTBh (ORCPT ); Thu, 24 Feb 2011 14:01:37 -0500 Date: Thu, 24 Feb 2011 20:01:26 +0100 (CET) From: Thomas Gleixner To: Stephen Boyd cc: David Brown , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 4/4] msm: scm: Get cacheline size from CTR In-Reply-To: <1298573085-23217-5-git-send-email-sboyd@codeaurora.org> Message-ID: References: <1298573085-23217-1-git-send-email-sboyd@codeaurora.org> <1298573085-23217-5-git-send-email-sboyd@codeaurora.org> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1746 Lines: 60 On Thu, 24 Feb 2011, Stephen Boyd wrote: > Instead of hardcoding the cacheline size as 32, get the cacheline > size from the CTR register. > > Signed-off-by: Stephen Boyd > --- > arch/arm/mach-msm/scm.c | 17 ++++++++++++----- > 1 files changed, 12 insertions(+), 5 deletions(-) > > diff --git a/arch/arm/mach-msm/scm.c b/arch/arm/mach-msm/scm.c > index cfa808d..0528c71 100644 > --- a/arch/arm/mach-msm/scm.c > +++ b/arch/arm/mach-msm/scm.c > @@ -26,9 +26,6 @@ > > #include "scm.h" > > -/* Cache line size for msm8x60 */ > -#define CACHELINESIZE 32 > - > #define SCM_ENOMEM -5 > #define SCM_EOPNOTSUPP -4 > #define SCM_EINVAL_ADDR -3 > @@ -207,6 +204,14 @@ static int __scm_call(const struct scm_command *cmd) > return ret; > } > > +static inline u32 dcache_line_size(void) > +{ > + u32 ctr; > + > + asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr)); > + return 4 << ((ctr >> 16) & 0xf); > +} > + > /** > * scm_call() - Send an SCM command > * @svc_id: service identifier > @@ -243,11 +248,13 @@ int scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf, size_t cmd_len, > do { > u32 start = (u32)rsp; > u32 end = (u32)scm_get_response_buffer(rsp) + resp_len; > - start &= ~(CACHELINESIZE - 1); > + u32 cacheline_size = dcache_line_size(); And why do you want to do that on every scm_call() invocation and on every loop of that code? If your dcache_line_size() changes at runtime, then you might have other problems. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/