From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932436AbcHIQWS (ORCPT ); Tue, 9 Aug 2016 12:22:18 -0400 Received: from foss.arm.com ([217.140.101.70]:43325 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932171AbcHIQWQ (ORCPT ); Tue, 9 Aug 2016 12:22:16 -0400 Message-ID: <57AA032F.6050704@arm.com> Date: Tue, 09 Aug 2016 17:22:07 +0100 From: James Morse User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Icedove/31.6.0 MIME-Version: 1.0 To: Suzuki K Poulose CC: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, will.deacon@arm.com, Geoff Levand Subject: Re: [PATCH 6/8] arm64: Introduce raw_{d,i}cache_line_size References: <1467977839-27543-1-git-send-email-suzuki.poulose@arm.com> <1467977839-27543-8-git-send-email-suzuki.poulose@arm.com> In-Reply-To: <1467977839-27543-8-git-send-email-suzuki.poulose@arm.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Suzuki, Sorry this fell through the cracks... On 08/07/16 12:37, Suzuki K Poulose wrote: > On systems with mismatched i/d cache min line sizes, we need to use > the smallest size possible across all CPUs. This will be done by fetching > the system wide safe value from CPU feature infrastructure. > However the some special users(e.g kexec, hibernate) would need the line > size on the CPU (rather than the system wide), when the system wide > feature may not be accessible. Provide another helper which will fetch > cache line size on the current CPU. > diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h > index d5025c6..a4bb3f5 100644 > --- a/arch/arm64/include/asm/assembler.h > +++ b/arch/arm64/include/asm/assembler.h > @@ -218,9 +218,10 @@ lr .req x30 // link register > .endm > > /* > - * dcache_line_size - get the minimum D-cache line size from the CTR register. > + * raw_dcache_line_size - get the minimum D-cache line size on this CPU > + * from the CTR register. > */ > - .macro dcache_line_size, reg, tmp > + .macro raw_dcache_line_size, reg, tmp > mrs \tmp, ctr_el0 // read CTR > ubfm \tmp, \tmp, #16, #19 // cache line size encoding > mov \reg, #4 // bytes per word > @@ -228,9 +229,17 @@ lr .req x30 // link register > .endm > > /* > - * icache_line_size - get the minimum I-cache line size from the CTR register. > + * dcache_line_size - get the safe D-cache line size across all CPUs > */ > - .macro icache_line_size, reg, tmp > + .macro dcache_line_size, reg, tmp > + raw_dcache_line_size \reg, \tmp > + .endm > + > +/* > + * raw_icache_line_size - get the minimum I-cache line size on this CPU > + * from the CTR register. > + */ > + .macro raw_icache_line_size, reg, tmp > mrs \tmp, ctr_el0 // read CTR > and \tmp, \tmp, #0xf // cache line size encoding > mov \reg, #4 // bytes per word > @@ -238,6 +247,13 @@ lr .req x30 // link register > .endm > > /* > + * icache_line_size - get the safe I-cache line size across all CPUs > + */ > + .macro icache_line_size, reg, tmp > + raw_icache_line_size \reg, \tmp > + .endm > + > +/* > * tcr_set_idmap_t0sz - update TCR.T0SZ so that we can load the ID map > */ > .macro tcr_set_idmap_t0sz, valreg, tmpreg > diff --git a/arch/arm64/kernel/hibernate-asm.S b/arch/arm64/kernel/hibernate-asm.S > index 46f29b6..4ebc6a1 100644 > --- a/arch/arm64/kernel/hibernate-asm.S > +++ b/arch/arm64/kernel/hibernate-asm.S > @@ -96,7 +96,7 @@ ENTRY(swsusp_arch_suspend_exit) > > add x1, x10, #PAGE_SIZE > /* Clean the copied page to PoU - based on flush_icache_range() */ > - dcache_line_size x2, x3 > + raw_dcache_line_size x2, x3 > sub x3, x2, #1 > bic x4, x10, x3 > 2: dc cvau, x4 /* clean D line / unified line */ Looks like no-change to me! If you think you need it: Acked-by: James Morse Thanks, James