From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [Linaro-acpi] [PATCH v5 1/2] Mailbox: Add support for Platform Communication Channel Date: Thu, 04 Sep 2014 21:00:11 +0200 Message-ID: <4354903.8scPjxmpFT@wuerfel> References: <1409782760-3958-1-git-send-email-ashwin.chaugule@linaro.org> <5470309.KpxVtJyk9p@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from mout.kundenserver.de ([212.227.126.187]:52499 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755125AbaIDTAX (ORCPT ); Thu, 4 Sep 2014 15:00:23 -0400 In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linaro-acpi@lists.linaro.org Cc: Ashwin Chaugule , linux acpi , Mark Brown , "Rafael J. Wysocki" On Thursday 04 September 2014 13:24:25 Ashwin Chaugule wrote: > On 4 September 2014 04:56, Arnd Bergmann wrote: > > >> + /* Write to the shared comm region. */ > >> + iowrite16(cmd, &generic_comm_base->command); > >> + > >> + /* Write Subspace MAGIC value so platform can identify destination. */ > >> + iowrite32((PCCS_SS_SIG_MAGIC | ss_idx), &generic_comm_base->signature); > >> + > >> + /* Flip CMD COMPLETE bit */ > >> + iowrite16(0, &generic_comm_base->status); > > > > using writel_relaxed/writew_relaxed should be more efficient here. > > > > x86 doesn't seem to have the write*_relaxed variants? They seem to > have read*_relaxed though. That sounds highly inconsistent and should probably be fixed. You could also use writew here, which would be the same as iowrite16 on ARM, but more efficient on x86. Arnd