From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29A13C433DB for ; Thu, 11 Feb 2021 16:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E14CF64E70 for ; Thu, 11 Feb 2021 16:58:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230046AbhBKQ6m (ORCPT ); Thu, 11 Feb 2021 11:58:42 -0500 Received: from foss.arm.com ([217.140.110.172]:54624 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230252AbhBKQ4O (ORCPT ); Thu, 11 Feb 2021 11:56:14 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5611E11D4; Thu, 11 Feb 2021 08:55:28 -0800 (PST) Received: from [192.168.0.110] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5CF773F73B; Thu, 11 Feb 2021 08:55:27 -0800 (PST) Subject: Re: [PATCH kvmtool 05/21] hw/i8042: Clean up data types To: Andre Przywara , Will Deacon , Julien Thierry Cc: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Marc Zyngier References: <20201210142908.169597-1-andre.przywara@arm.com> <20201210142908.169597-6-andre.przywara@arm.com> From: Alexandru Elisei Message-ID: <04b5f537-1594-61b9-b7ef-4062e732e380@arm.com> Date: Thu, 11 Feb 2021 16:55:43 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20201210142908.169597-6-andre.przywara@arm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Andre, On 12/10/20 2:28 PM, Andre Przywara wrote: > The i8042 is clearly an 8-bit era device, so there is little room for > 32-bit registers. > Clean up the data types used. > > Signed-off-by: Andre Przywara > --- > hw/i8042.c | 20 ++++++++++---------- > 1 file changed, 10 insertions(+), 10 deletions(-) > > diff --git a/hw/i8042.c b/hw/i8042.c > index 37a99a2d..36ee183f 100644 > --- a/hw/i8042.c > +++ b/hw/i8042.c > @@ -64,11 +64,11 @@ > struct kbd_state { > struct kvm *kvm; > > - char kq[QUEUE_SIZE]; /* Keyboard queue */ > + u8 kq[QUEUE_SIZE]; /* Keyboard queue */ > int kread, kwrite; /* Indexes into the queue */ > int kcount; /* number of elements in queue */ > > - char mq[QUEUE_SIZE]; > + u8 mq[QUEUE_SIZE]; > int mread, mwrite; > int mcount; I think the write_cmd field further down should also be u8 because it stores the first byte of a command (and it's set only to an 8 bit value in kbd_write_command()). Otherwise, it looks ok to me. osdev wiki seems to confirm that the device is indeed 8 bit only, and all the registers are 8 bit now: Reviewed-by: Alexandru Elisei Thanks, Alex > > @@ -173,9 +173,9 @@ static void kbd_write_command(struct kvm *kvm, u8 val) > /* > * Called when the OS reads from port 0x60 (PS/2 data) > */ > -static u32 kbd_read_data(void) > +static u8 kbd_read_data(void) > { > - u32 ret; > + u8 ret; > int i; > > if (state.kcount != 0) { > @@ -202,9 +202,9 @@ static u32 kbd_read_data(void) > /* > * Called when the OS read from port 0x64, the command port > */ > -static u32 kbd_read_status(void) > +static u8 kbd_read_status(void) > { > - return (u32)state.status; > + return state.status; > } > > /* > @@ -212,7 +212,7 @@ static u32 kbd_read_status(void) > * Things written here are generally arguments to commands previously > * written to port 0x64 and stored in state.write_cmd > */ > -static void kbd_write_data(u32 val) > +static void kbd_write_data(u8 val) > { > switch (state.write_cmd) { > case I8042_CMD_CTL_WCTR: > @@ -304,8 +304,8 @@ static bool kbd_in(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void * > break; > } > case I8042_DATA_REG: { > - u32 value = kbd_read_data(); > - ioport__write32(data, value); > + u8 value = kbd_read_data(); > + ioport__write8(data, value); > break; > } > case I8042_PORT_B_REG: { > @@ -328,7 +328,7 @@ static bool kbd_out(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void > break; > } > case I8042_DATA_REG: { > - u32 value = ioport__read32(data); > + u8 value = ioport__read8(data); > kbd_write_data(value); > break; > }