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=-12.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 293C1C433E2 for ; Tue, 8 Sep 2020 16:50:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB1162075A for ; Tue, 8 Sep 2020 16:50:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uxw883jD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731677AbgIHQux (ORCPT ); Tue, 8 Sep 2020 12:50:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732051AbgIHQsj (ORCPT ); Tue, 8 Sep 2020 12:48:39 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C393C06179A; Tue, 8 Sep 2020 09:48:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=rHSBc/M4bEuOb9Ey0sWSjsN3haNI1yyBuzSqz9ajJzQ=; b=uxw883jDfwFTqx1kQc02sE7gz5 T6genhEdpIBo8JlGHDRJLZO1GDNKrAaT3hBfl5H8ctRGOHxy5Z1YqDRFk+WjfvWPsdn+D8DsTPCyq vDvPDJ1bItTKRBJS/MqIg7Y+g0ET2HXq5KwdIxujVMlz4QZvDS7BAxR4hYzQ1/G5mvt8WnVoFDugj CMJfssAPg1+RF/6Eh1DefJdk2m+sdW0ZQh/oTrXkeco0dHfYJ5j/onoZm1u7SowznLxDFMRAMkPa/ ngnL6UNUTGFCYWQfM4yvmctPYaU0E3BbqiVBxwE7Fc5RZJfgv+ZWoYjmfC2K2WKhCQkuUdqpuhNN/ CsdNekXg==; Received: from [2001:4bb8:184:af1:3dc3:9c83:fc6c:e0f] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFgn1-0001Tl-LF; Tue, 08 Sep 2020 16:48:15 +0000 From: Christoph Hellwig To: Tony Luck , Fenghua Yu , Thomas Bogendoerfer , iommu@lists.linux-foundation.org Cc: Tomasz Figa , Joerg Roedel , Robin Murphy , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org Subject: [PATCH 12/12] dma-mapping: move the dma_declare_coherent_memory documentation Date: Tue, 8 Sep 2020 18:47:58 +0200 Message-Id: <20200908164758.3177341-13-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200908164758.3177341-1-hch@lst.de> References: <20200908164758.3177341-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org dma_declare_coherent_memory should not be in a DMA API guide aimed at driver writers (that is consumers of the API). Move it to a comment near the function instead. Signed-off-by: Christoph Hellwig --- Documentation/core-api/dma-api.rst | 24 ------------------------ kernel/dma/coherent.c | 17 +++++++++++++++++ 2 files changed, 17 insertions(+), 24 deletions(-) diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst index 3b3abbbb4b9a6f..90239348b30f6f 100644 --- a/Documentation/core-api/dma-api.rst +++ b/Documentation/core-api/dma-api.rst @@ -586,30 +586,6 @@ the DMA_ATTR_NON_CONSISTENT flag starting at virtual address vaddr and continuing on for size. Again, you *must* observe the cache line boundaries when doing this. -:: - - int - dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size); - -Declare region of memory to be handed out by dma_alloc_coherent() when -it's asked for coherent memory for this device. - -phys_addr is the CPU physical address to which the memory is currently -assigned (this will be ioremapped so the CPU can access the region). - -device_addr is the DMA address the device needs to be programmed -with to actually address this memory (this will be handed out as the -dma_addr_t in dma_alloc_coherent()). - -size is the size of the area (must be multiples of PAGE_SIZE). - -As a simplification for the platforms, only *one* such region of -memory may be declared per device. - -For reasons of efficiency, most platforms choose to track the declared -region only at the granularity of a page. For smaller allocations, -you should use the dma_pool() API. Part III - Debug drivers use of the DMA-API ------------------------------------------- diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index 2a0c4985f38e41..f85d14bbfcbe03 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -107,6 +107,23 @@ static int dma_assign_coherent_memory(struct device *dev, return 0; } +/* + * Declare a region of memory to be handed out by dma_alloc_coherent() when it + * is asked for coherent memory for this device. This shall only be used + * from platform code, usually based on the device tree description. + * + * phys_addr is the CPU physical address to which the memory is currently + * assigned (this will be ioremapped so the CPU can access the region). + * + * device_addr is the DMA address the device needs to be programmed with to + * actually address this memory (this will be handed out as the dma_addr_t in + * dma_alloc_coherent()). + * + * size is the size of the area (must be a multiple of PAGE_SIZE). + * + * As a simplification for the platforms, only *one* such region of memory may + * be declared per device. + */ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) { -- 2.28.0 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=-12.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 5C8FDC43461 for ; Tue, 8 Sep 2020 16:48:29 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EBC1E20759 for ; Tue, 8 Sep 2020 16:48:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uxw883jD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EBC1E20759 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id D9F3085D97; Tue, 8 Sep 2020 16:48:28 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id miAODg2vRAmD; Tue, 8 Sep 2020 16:48:28 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 598F085BD1; Tue, 8 Sep 2020 16:48:28 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 550ADC0052; Tue, 8 Sep 2020 16:48:28 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id E95C4C0051 for ; Tue, 8 Sep 2020 16:48:26 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id D21BA2C35C for ; Tue, 8 Sep 2020 16:48:26 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2xchZYMk7fEX for ; Tue, 8 Sep 2020 16:48:20 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by silver.osuosl.org (Postfix) with ESMTPS id 2300A2E100 for ; Tue, 8 Sep 2020 16:48:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=rHSBc/M4bEuOb9Ey0sWSjsN3haNI1yyBuzSqz9ajJzQ=; b=uxw883jDfwFTqx1kQc02sE7gz5 T6genhEdpIBo8JlGHDRJLZO1GDNKrAaT3hBfl5H8ctRGOHxy5Z1YqDRFk+WjfvWPsdn+D8DsTPCyq vDvPDJ1bItTKRBJS/MqIg7Y+g0ET2HXq5KwdIxujVMlz4QZvDS7BAxR4hYzQ1/G5mvt8WnVoFDugj CMJfssAPg1+RF/6Eh1DefJdk2m+sdW0ZQh/oTrXkeco0dHfYJ5j/onoZm1u7SowznLxDFMRAMkPa/ ngnL6UNUTGFCYWQfM4yvmctPYaU0E3BbqiVBxwE7Fc5RZJfgv+ZWoYjmfC2K2WKhCQkuUdqpuhNN/ CsdNekXg==; Received: from [2001:4bb8:184:af1:3dc3:9c83:fc6c:e0f] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kFgn1-0001Tl-LF; Tue, 08 Sep 2020 16:48:15 +0000 From: Christoph Hellwig To: Tony Luck , Fenghua Yu , Thomas Bogendoerfer , iommu@lists.linux-foundation.org Subject: [PATCH 12/12] dma-mapping: move the dma_declare_coherent_memory documentation Date: Tue, 8 Sep 2020 18:47:58 +0200 Message-Id: <20200908164758.3177341-13-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200908164758.3177341-1-hch@lst.de> References: <20200908164758.3177341-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Cc: linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, Robin Murphy X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" dma_declare_coherent_memory should not be in a DMA API guide aimed at driver writers (that is consumers of the API). Move it to a comment near the function instead. Signed-off-by: Christoph Hellwig --- Documentation/core-api/dma-api.rst | 24 ------------------------ kernel/dma/coherent.c | 17 +++++++++++++++++ 2 files changed, 17 insertions(+), 24 deletions(-) diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst index 3b3abbbb4b9a6f..90239348b30f6f 100644 --- a/Documentation/core-api/dma-api.rst +++ b/Documentation/core-api/dma-api.rst @@ -586,30 +586,6 @@ the DMA_ATTR_NON_CONSISTENT flag starting at virtual address vaddr and continuing on for size. Again, you *must* observe the cache line boundaries when doing this. -:: - - int - dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size); - -Declare region of memory to be handed out by dma_alloc_coherent() when -it's asked for coherent memory for this device. - -phys_addr is the CPU physical address to which the memory is currently -assigned (this will be ioremapped so the CPU can access the region). - -device_addr is the DMA address the device needs to be programmed -with to actually address this memory (this will be handed out as the -dma_addr_t in dma_alloc_coherent()). - -size is the size of the area (must be multiples of PAGE_SIZE). - -As a simplification for the platforms, only *one* such region of -memory may be declared per device. - -For reasons of efficiency, most platforms choose to track the declared -region only at the granularity of a page. For smaller allocations, -you should use the dma_pool() API. Part III - Debug drivers use of the DMA-API ------------------------------------------- diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index 2a0c4985f38e41..f85d14bbfcbe03 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -107,6 +107,23 @@ static int dma_assign_coherent_memory(struct device *dev, return 0; } +/* + * Declare a region of memory to be handed out by dma_alloc_coherent() when it + * is asked for coherent memory for this device. This shall only be used + * from platform code, usually based on the device tree description. + * + * phys_addr is the CPU physical address to which the memory is currently + * assigned (this will be ioremapped so the CPU can access the region). + * + * device_addr is the DMA address the device needs to be programmed with to + * actually address this memory (this will be handed out as the dma_addr_t in + * dma_alloc_coherent()). + * + * size is the size of the area (must be a multiple of PAGE_SIZE). + * + * As a simplification for the platforms, only *one* such region of memory may + * be declared per device. + */ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) { -- 2.28.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Tue, 08 Sep 2020 16:47:58 +0000 Subject: [PATCH 12/12] dma-mapping: move the dma_declare_coherent_memory documentation Message-Id: <20200908164758.3177341-13-hch@lst.de> List-Id: References: <20200908164758.3177341-1-hch@lst.de> In-Reply-To: <20200908164758.3177341-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tony Luck , Fenghua Yu , Thomas Bogendoerfer , iommu@lists.linux-foundation.org Cc: Tomasz Figa , Joerg Roedel , Robin Murphy , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org dma_declare_coherent_memory should not be in a DMA API guide aimed at driver writers (that is consumers of the API). Move it to a comment near the function instead. Signed-off-by: Christoph Hellwig --- Documentation/core-api/dma-api.rst | 24 ------------------------ kernel/dma/coherent.c | 17 +++++++++++++++++ 2 files changed, 17 insertions(+), 24 deletions(-) diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst index 3b3abbbb4b9a6f..90239348b30f6f 100644 --- a/Documentation/core-api/dma-api.rst +++ b/Documentation/core-api/dma-api.rst @@ -586,30 +586,6 @@ the DMA_ATTR_NON_CONSISTENT flag starting at virtual address vaddr and continuing on for size. Again, you *must* observe the cache line boundaries when doing this. -:: - - int - dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size); - -Declare region of memory to be handed out by dma_alloc_coherent() when -it's asked for coherent memory for this device. - -phys_addr is the CPU physical address to which the memory is currently -assigned (this will be ioremapped so the CPU can access the region). - -device_addr is the DMA address the device needs to be programmed -with to actually address this memory (this will be handed out as the -dma_addr_t in dma_alloc_coherent()). - -size is the size of the area (must be multiples of PAGE_SIZE). - -As a simplification for the platforms, only *one* such region of -memory may be declared per device. - -For reasons of efficiency, most platforms choose to track the declared -region only at the granularity of a page. For smaller allocations, -you should use the dma_pool() API. Part III - Debug drivers use of the DMA-API ------------------------------------------- diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index 2a0c4985f38e41..f85d14bbfcbe03 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -107,6 +107,23 @@ static int dma_assign_coherent_memory(struct device *dev, return 0; } +/* + * Declare a region of memory to be handed out by dma_alloc_coherent() when it + * is asked for coherent memory for this device. This shall only be used + * from platform code, usually based on the device tree description. + * + * phys_addr is the CPU physical address to which the memory is currently + * assigned (this will be ioremapped so the CPU can access the region). + * + * device_addr is the DMA address the device needs to be programmed with to + * actually address this memory (this will be handed out as the dma_addr_t in + * dma_alloc_coherent()). + * + * size is the size of the area (must be a multiple of PAGE_SIZE). + * + * As a simplification for the platforms, only *one* such region of memory may + * be declared per device. + */ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size) { -- 2.28.0