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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 E7E32C432BE for ; Tue, 27 Jul 2021 10:06:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D49AA61406 for ; Tue, 27 Jul 2021 10:06:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236165AbhG0KGz (ORCPT ); Tue, 27 Jul 2021 06:06:55 -0400 Received: from foss.arm.com ([217.140.110.172]:36910 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236105AbhG0KGx (ORCPT ); Tue, 27 Jul 2021 06:06:53 -0400 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 F15D81FB; Tue, 27 Jul 2021 03:06:52 -0700 (PDT) Received: from lpieralisi (e121166-lin.cambridge.arm.com [10.1.196.255]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 586893F73D; Tue, 27 Jul 2021 03:06:51 -0700 (PDT) Date: Tue, 27 Jul 2021 11:06:45 +0100 From: Lorenzo Pieralisi To: Ard Biesheuvel Cc: Linux Kernel Mailing List , Will Deacon , Hanjun Guo , Sudeep Holla , Catalin Marinas , "Rafael J. Wysocki" , ACPI Devel Maling List , Linux ARM , Veronika kabatova , Robin Murphy Subject: Re: [PATCH] ACPI: Add memory semantics to acpi_os_map_memory() Message-ID: <20210727100645.GA7108@lpieralisi> References: <20210726100026.12538-1-lorenzo.pieralisi@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 26, 2021 at 05:55:33PM +0200, Ard Biesheuvel wrote: > On Mon, 26 Jul 2021 at 12:00, Lorenzo Pieralisi > wrote: > > > > The memory attributes attached to memory regions depend on architecture > > specific mappings. > > > > For some memory regions, the attributes specified by firmware (eg > > uncached) are not sufficient to determine how a memory region should be > > mapped by an OS (for instance a region that is define as uncached in > > firmware can be mapped as Normal or Device memory on arm64) and > > therefore the OS must be given control on how to map the region to match > > the expected mapping behaviour (eg if a mapping is requested with memory > > semantics, it must allow unaligned accesses). > > > > Rework acpi_os_map_memory() and acpi_os_ioremap() back-end to split > > them into two separate code paths: > > > > acpi_os_memmap() -> memory semantics > > acpi_os_ioremap() -> MMIO semantics > > > > The split allows the architectural implementation back-ends to detect > > the default memory attributes required by the mapping in question > > (ie the mapping API defines the semantics memory vs MMIO) and map the > > memory accordingly. > > > > Link: https://lore.kernel.org/linux-arm-kernel/31ffe8fc-f5ee-2858-26c5-0fd8bdd68702@arm.com > > Signed-off-by: Lorenzo Pieralisi > > Cc: Ard Biesheuvel > > Cc: Will Deacon > > Cc: Hanjun Guo > > Cc: Sudeep Holla > > Cc: Catalin Marinas > > Cc: "Rafael J. Wysocki" > > For the patch in general > > Acked-by: Ard Biesheuvel Thanks ! [...] > > -void __iomem __ref > > -*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > +static void __iomem __ref > > +*__acpi_os_map_iomem(acpi_physical_address phys, acpi_size size, bool memory) > > { > > struct acpi_ioremap *map; > > void __iomem *virt; > > @@ -353,7 +356,7 @@ void __iomem __ref > > > > pg_off = round_down(phys, PAGE_SIZE); > > pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; > > - virt = acpi_map(phys, size); > > + virt = acpi_map(phys, size, memory); > > if (!virt) { > > mutex_unlock(&acpi_ioremap_lock); > > kfree(map); > > @@ -372,11 +375,17 @@ void __iomem __ref > > mutex_unlock(&acpi_ioremap_lock); > > return map->virt + (phys - map->phys); > > } > > + > > +void __iomem __ref > > +*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > I am aware that this just duplicated the prototype above, but I think > this should be > > void __iomem *__ref > > given that the __ref comes after the * in the prototype below. Yes I just moved/duplicated the prototype above but I believe this is consistent with include/acpi/acpi_io.h unless I have not understood what you meant ? It is probably worth changing it in both places to void __iomem *__ref ? I can do that with an additional patch. > > > +{ > > + return __acpi_os_map_iomem(phys, size, false); > > +} > > EXPORT_SYMBOL_GPL(acpi_os_map_iomem); > > > > void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) > > { > > - return (void *)acpi_os_map_iomem(phys, size); > > + return (void *)__acpi_os_map_iomem(phys, size, true); > > I think this should be (__force void *) to shut up sparse address > space warnings. Yes I can add that attribute in an additional patch and rebase this one on top of it. Thanks, Lorenzo > > > } > > EXPORT_SYMBOL_GPL(acpi_os_map_memory); > > > > diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h > > index 027faa8883aa..a0212e67d6f4 100644 > > --- a/include/acpi/acpi_io.h > > +++ b/include/acpi/acpi_io.h > > @@ -14,6 +14,14 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, > > } > > #endif > > > > +#ifndef acpi_os_memmap > > +static inline void __iomem *acpi_os_memmap(acpi_physical_address phys, > > + acpi_size size) > > +{ > > + return ioremap_cache(phys, size); > > +} > > +#endif > > + > > extern bool acpi_permanent_mmap; > > > > void __iomem __ref > > -- > > 2.31.0 > >