From patchwork Wed Sep 13 17:01:49 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Palmer Dabbelt X-Patchwork-Id: 9951689 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 54A2360360 for ; Wed, 13 Sep 2017 17:02:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 42C7C28635 for ; Wed, 13 Sep 2017 17:02:29 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 36A2528968; Wed, 13 Sep 2017 17:02:29 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BDD4628635 for ; Wed, 13 Sep 2017 17:02:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751330AbdIMRB6 (ORCPT ); Wed, 13 Sep 2017 13:01:58 -0400 Received: from mail-pg0-f65.google.com ([74.125.83.65]:37885 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbdIMRBv (ORCPT ); Wed, 13 Sep 2017 13:01:51 -0400 Received: by mail-pg0-f65.google.com with SMTP id v5so373046pgn.4 for ; Wed, 13 Sep 2017 10:01:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dabbelt-com.20150623.gappssmtp.com; s=20150623; h=date:subject:in-reply-to:cc:from:to:message-id:mime-version; bh=JxDms+ofuNe99U3KRFme3CI7GtpGUwEAEEQutUCTNfQ=; b=FogDVJ70tWEo8dEVAEv+vjZBwT6lSqJhCO4AmbupG8nqpa1q8eZPdRQ5HR7JdTXGGr RDTOb+h03WQJlY9Q/RkDU1g5bvfrDzAj3QPJwIJ9jh7NbWE35mnr87RBb09e7lr2vJM/ KhgfqSuQI1LKeZ8s+5OrOXVKji5LBB9AYITB8Z0fDNzjaPKXR4t56mzWH2gWOdIusnsY Nx2npK0EdoGGrIMZGztU+IXUhwUysDj9wmeK/zWBNv/bgVGWIFxjURwv1SVlc7z9h0hQ j6afT2Fxlr0Z7sUhxOxcqDr+gQMp+gH88+rzx3+jOSHQlSK4pAPYRadv4T+96h5lp4rw ck3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:subject:in-reply-to:cc:from:to:message-id :mime-version; bh=JxDms+ofuNe99U3KRFme3CI7GtpGUwEAEEQutUCTNfQ=; b=semZEJllJaVn1828CdtOhZKO5I3VIEmTjOQN9l/XCEr4PWWo7Q+xK3z4BmFQZYe7PU qePxsNcHbWg1M/VVXg3TFN+JNwXIcC8ZNvD4rre8XTFbn+iuRfIkZUd1vbL8WCKXQuQp yThjdHc9F9r0dJx0+VvxAU5K/Vcn5fBUMAnm78XuTAu/Ebpm2wa+oG5Z68tW97nB7f6b P1q1v9sZEJOZFvsdiRI3UyLbCuVDZgRjdwE6DNWwhKA8/rw87triclOnj3ejo7c4qv1p HF/vuLJCHGSdGnZs22BJ9hWAjTJT/D8iWDVNZjygei2uH5vTK1vbgvYlYnMvNs/mqSsL nssA== X-Gm-Message-State: AHPjjUg4AjoiAhW4PM2tPkyx485TgnWrtD74/GmFDhxS+pY2G/qPIWKN yzOIqcWTiEd2YQPd X-Google-Smtp-Source: ADKCNb44VjAPblSXJzDAczIJT4svZyewQh2I3Y/BB8EWxd4IFgtrrAzkKq84ZEe0354fGbxvmJ+Vlg== X-Received: by 10.84.129.65 with SMTP id 59mr21091957plb.442.1505322110600; Wed, 13 Sep 2017 10:01:50 -0700 (PDT) Received: from localhost ([12.206.222.5]) by smtp.gmail.com with ESMTPSA id t81sm26291020pfg.154.2017.09.13.10.01.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 13 Sep 2017 10:01:49 -0700 (PDT) Date: Wed, 13 Sep 2017 10:01:49 -0700 (PDT) X-Google-Original-Date: Wed, 13 Sep 2017 09:53:15 PDT (-0700) Subject: Re: [PATCH v8 15/18] RISC-V: Device, timer, IRQs, and the SBI In-Reply-To: CC: peterz@infradead.org, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, dmitriy@oss-tech.org, yamada.masahiro@socionext.com, mmarek@suse.com, albert@sifive.com, will.deacon@arm.com, boqun.feng@gmail.com, oleg@redhat.com, mingo@redhat.com, daniel.lezcano@linaro.org, gregkh@linuxfoundation.org, jslaby@suse.com, davem@davemloft.net, mchehab@kernel.org, hverkuil@xs4all.nl, rdunlap@infradead.org, viro@zeniv.linux.org.uk, mhiramat@kernel.org, fweisbec@gmail.com, mcgrof@kernel.org, dledford@redhat.com, bart.vanassche@sandisk.com, sstabellini@kernel.org, mpe@ellerman.id.au, rmk+kernel@armlinux.org.uk, paul.gortmaker@windriver.com, nicolas.dichtel@6wind.com, linux@roeck-us.net, heiko.carstens@de.ibm.com, schwidefsky@de.ibm.com, geert@linux-m68k.org, akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, jiri@mellanox.com, vgupta@synopsys.com, airlied@redhat.com, jk@ozlabs.org, chris@chris-wilson.co.uk, Jason@zx2c4.com, paulmck@linux.vnet.ibm.com, ncardwell@google.com, linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, patches@groups.riscv.org From: Palmer Dabbelt To: Arnd Bergmann Message-ID: Mime-Version: 1.0 (MHng) Sender: linux-kbuild-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Wed, 13 Sep 2017 08:36:54 PDT (-0700), Arnd Bergmann wrote: > On Tue, Sep 12, 2017 at 11:57 PM, Palmer Dabbelt wrote: > >> + >> +/* RISC-V TileLink and PCIe share the share address space */ >> +#define PCI_DMA_BUS_IS_PHYS 1 > > To be pedantic, the comment here is not helpful. Ya, you're right: TileLink isn't a RISC-V thing, so the comment doesn't even make sense. > PCI_DMA_BUS_IS_PHYS is a misnamed symbol that indicates > the absence of an IOMMU. When it is zero, the scsi and network > layers assume that they don't need to use bounce buffers > since the IOMMU can usually address any RAM even if a > PCI device cannot. OK. How does this look? --- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/arch/riscv/include/asm/pci.h b/arch/riscv/include/asm/pci.h index 285747fa2ef0..0f2fc9ef20fc 100644 --- a/arch/riscv/include/asm/pci.h +++ b/arch/riscv/include/asm/pci.h @@ -26,7 +26,7 @@ /* RISC-V shim does not initialize PCI bus */ #define pcibios_assign_all_busses() 1 -/* RISC-V TileLink and PCIe share the share address space */ +/* We do not have an IOMMU */ #define PCI_DMA_BUS_IS_PHYS 1 extern int isa_dma_bridge_buggy;