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=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 79065C3A5A2 for ; Wed, 4 Sep 2019 01:05:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D06521897 for ; Wed, 4 Sep 2019 01:05:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=flygoat.com header.i=@flygoat.com header.b="vMGCEyf1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726925AbfIDBFC (ORCPT ); Tue, 3 Sep 2019 21:05:02 -0400 Received: from forward103j.mail.yandex.net ([5.45.198.246]:46471 "EHLO forward103j.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726589AbfIDBFB (ORCPT ); Tue, 3 Sep 2019 21:05:01 -0400 Received: from mxback2j.mail.yandex.net (mxback2j.mail.yandex.net [IPv6:2a02:6b8:0:1619::10b]) by forward103j.mail.yandex.net (Yandex) with ESMTP id E511567401AA; Wed, 4 Sep 2019 04:04:57 +0300 (MSK) Received: from smtp4p.mail.yandex.net (smtp4p.mail.yandex.net [2a02:6b8:0:1402::15:6]) by mxback2j.mail.yandex.net (nwsmtp/Yandex) with ESMTP id iM9c7mkalx-4vNuEoEX; Wed, 04 Sep 2019 04:04:57 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=flygoat.com; s=mail; t=1567559097; bh=bbtBHr5oY2eX7Wq/nNBFqwhRQ7lHiT4aj3By06XAaqM=; h=In-Reply-To:From:To:Subject:Cc:Date:References:Message-ID; b=vMGCEyf1rkBjCgcBHsbbpS4qpfpxa/+f6TZwQjVyoAuFUyU4q/KlzUXpruOtrz1gO 7ws9XETp2UHc4ilruaeLYJZKOIEZV1NY+WAYD80UYPNZFFxeu1shJB0DasRZq4jdwE qMTIZPOXJcTpNSjQCSl8Wd7hLGkrySMI9GetvsHE= Authentication-Results: mxback2j.mail.yandex.net; dkim=pass header.i=@flygoat.com Received: by smtp4p.mail.yandex.net (nwsmtp/Yandex) with ESMTPSA id A1hb0npBaY-4hbKk3fj; Wed, 04 Sep 2019 04:04:47 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) Subject: Re: [PATCH 022/120] MIPS: R5900: Support 64-bit inq() and outq() macros in 32-bit kernels To: Fredrik Noring , Paul Burton , linux-mips@vger.kernel.org Cc: "Maciej W. Rozycki" , =?UTF-8?Q?J=c3=bcrgen_Urban?= References: <7ea8b1211bceb8193154b51ad4241e7c0b86547d.1567326213.git.noring@nocrew.org> From: Jiaxun Yang Message-ID: <975d5c12-2918-80e7-3ab5-93c678e1a2e0@flygoat.com> Date: Wed, 4 Sep 2019 09:04:18 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.0 MIME-Version: 1.0 In-Reply-To: <7ea8b1211bceb8193154b51ad4241e7c0b86547d.1567326213.git.noring@nocrew.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org 在 2019/9/1 23:46, Fredrik Noring 写道: > PlayStation 2 hardware such as the Graphics Synthesizer requires 64-bit > register reads and writes[1], also in 32-bit kernels. Interrupts must be > disabled when manipulating 64-bit registers unless the kernel saves and > restores 64-bit registers in the interrupt and context switch handlers. Hi Fredrik, Why don't we just build a 64bit kernel rather than do these hacks? Any hardware/firmware issue blocks 64bit kernel? -- Jiaxun Yang > References: > > [1] "EE User's Manual", version 6.0, Sony Computer Entertainment Inc., > p. 26: GS privileged registers must be accessed using LD/SD > instructions. > > Signed-off-by: Fredrik Noring > ---