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 Received: from mail.librecores.org (lists.librecores.org [88.198.125.70]) by smtp.lore.kernel.org (Postfix) with ESMTP id C975EECAAD4 for ; Mon, 29 Aug 2022 08:18:41 +0000 (UTC) Received: from [172.31.1.100] (localhost.localdomain [127.0.0.1]) by mail.librecores.org (Postfix) with ESMTP id A1DFF248E8; Mon, 29 Aug 2022 10:18:40 +0200 (CEST) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by mail.librecores.org (Postfix) with ESMTP id 08C5924994 for ; Mon, 29 Aug 2022 10:18:38 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661761118; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=lDag/OyOW5J2lHZGYxPXL7WM7zq/jil/fCsPlf3BqyI=; b=KVcqMKJSrTzu6wMWPq2dTTmzUAqhc2eJYqbC2DCUDaXyLiZLEEMM6x20bAAqKB9u6r8Yyr 8/mL18sD3fOGzgT8rTyDpw3SvexVzQaNuZpZQph+IYZcTA7Jc+GUr8mub40Ls6tcd1iW9M MZ7pMxVnDbuNcF9CCkGM+/Dr/m2psB8= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-563-4rDcRiYtPEGtt-VtKCIOuA-1; Mon, 29 Aug 2022 04:18:34 -0400 X-MC-Unique: 4rDcRiYtPEGtt-VtKCIOuA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D338C3C0E201; Mon, 29 Aug 2022 08:18:33 +0000 (UTC) Received: from localhost (ovpn-12-153.pek2.redhat.com [10.72.12.153]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 7847C4011A58; Mon, 29 Aug 2022 08:18:31 +0000 (UTC) Date: Mon, 29 Aug 2022 16:18:27 +0800 From: Baoquan He To: Stafford Horne Subject: Re: [PATCH v2 07/11] openrisc: mm: Convert to GENERIC_IOREMAP Message-ID: References: <20220820003125.353570-1-bhe@redhat.com> <20220820003125.353570-8-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 X-BeenThere: openrisc@lists.librecores.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Discussion around the OpenRISC processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jonas Bonn , wangkefeng.wang@huawei.com, linux-kernel@vger.kernel.org, Christoph Hellwig , linux-mm@kvack.org, openrisc@lists.librecores.org, akpm@linux-foundation.org, agordeev@linux.ibm.com, linux-arm-kernel@lists.infradead.org Errors-To: openrisc-bounces@lists.librecores.org Sender: "OpenRISC" On 08/29/22 at 06:42am, Stafford Horne wrote: > On Mon, Aug 29, 2022 at 09:40:24AM +0800, Baoquan He wrote: > > On 08/21/22 at 12:03am, Christoph Hellwig wrote: > > > > + if (unlikely(!mem_init_done)) { > > > > if ((fixmaps_used + (size >> PAGE_SHIFT)) > FIX_N_IOREMAPS) > > > > + return IOMEM_ERR_PTR(ret); > > > > v = fix_to_virt(FIX_IOREMAP_BEGIN + fixmaps_used); > > > > fixmaps_used += (size >> PAGE_SHIFT); > > > > > > > > + if (ioremap_page_range(v, v + size, p, __pgprot(*prot_val))) { > > > > fixmaps_used -= (size >> PAGE_SHIFT); > > > > + return IOMEM_ERR_PTR(ret); > > > > + } > > > > + > > > > + return (void __iomem *)(offset + (char *)v); > > > > } > > > > > > This code needs to go away, and all very early boot uses of ioremap > > > need to switch to use early_ioremap insted. > > > > Makes sense. On openrisc, the thing is I didn't find one place where > > ioremap() is called in arch code. I can cut the early ioremap out and > > wrap into a separate early_ioremap() function, however I don't know > > where to put it. Not sure if I miss anything or openrisc doesn't really > > need early ioremap. > > Hi, > > I don't know of any early_ioremap usage either in openrisc, maybe some drivers > use it? However, we do not initialize any early_ioremap infrastructure in > openrisc so that may cause issues if it is used. The variable mem_init_done indicates if mem_init() is called or not. Driver should only initialize after mem_init(). With my understanding, the early ioremap is only needed by arch code. > > We can try to remove it all. I tested these below additional changes and they > work, if you want to add them we can see if kbuild robots pick anything up. Very helpful information. Then I will remove the !mem_init_done part code as you listed below, let's see how test robots react. Thanks a lot. > > -Stafford > > diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c > index bc41660e1fb0..ffe6d5e2b5fe 100644 > --- a/arch/openrisc/mm/ioremap.c > +++ b/arch/openrisc/mm/ioremap.c > @@ -22,14 +22,10 @@ > > extern int mem_init_done; > > -static unsigned int fixmaps_used __initdata; > - > void __iomem * > arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val) > { > - phys_addr_t p; > - unsigned long v; > - unsigned long offset, last_addr, addr = *paddr; > + unsigned long last_addr, addr = *paddr; > int ret = -EINVAL; > > /* Don't allow wraparound or zero size */ > @@ -37,27 +33,6 @@ arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val) > if (!size || last_addr < addr) > return IOMEM_ERR_PTR(ret); > > - /* > - * Mappings have to be page-aligned > - */ > - offset = addr & ~PAGE_MASK; > - p = addr & PAGE_MASK; > - size = PAGE_ALIGN(last_addr + 1) - p; > - > - if (unlikely(!mem_init_done)) { > - if ((fixmaps_used + (size >> PAGE_SHIFT)) > FIX_N_IOREMAPS) > - return IOMEM_ERR_PTR(ret); > - v = fix_to_virt(FIX_IOREMAP_BEGIN + fixmaps_used); > - fixmaps_used += (size >> PAGE_SHIFT); > - > - if (ioremap_page_range(v, v + size, p, __pgprot(*prot_val))) { > - fixmaps_used -= (size >> PAGE_SHIFT); > - return IOMEM_ERR_PTR(ret); > - } > - > - return (void __iomem *)(offset + (char *)v); > - } > - > return NULL; > } > >