Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753005Ab3JWS11 (ORCPT ); Wed, 23 Oct 2013 14:27:27 -0400 Received: from mail-ie0-f174.google.com ([209.85.223.174]:39685 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751412Ab3JWS10 (ORCPT ); Wed, 23 Oct 2013 14:27:26 -0400 MIME-Version: 1.0 In-Reply-To: <1374740897-20304-2-git-send-email-haver@vnet.ibm.com> References: <1374740897-20304-1-git-send-email-haver@vnet.ibm.com> <1374740897-20304-2-git-send-email-haver@vnet.ibm.com> From: Bjorn Helgaas Date: Wed, 23 Oct 2013 12:27:05 -0600 Message-ID: Subject: Re: [PATCH] Generic WorkQueue Engine (GenWQE) device driver To: Frank Haverkamp Cc: "linux-kernel@vger.kernel.org" , Arnd Bergmann , Greg Kroah-Hartman , cody@linux.vnet.ibm.com, Martin Schwidefsky , utz.bacher@de.ibm.com, jsvogt@de.ibm.com, MIJUNG@de.ibm.com, Thadeu Lima de Souza Cascardo , michael@ibmra.de Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1900 Lines: 41 On Thu, Jul 25, 2013 at 2:28 AM, Frank Haverkamp wrote: > The GenWQE card provides access to a generic work queue into which the > work can be put, which should be executed, e.g. compression or > decompression request, or whatever the card was configured to do. > > Each request comes with a set of input data (ASV) and will produce some > output data (ASIV). The request will also contain a sequence number, > some timestamps and a command code/subcode plus some fields for hardware-/ > software-interaction. > > A request can contain references to blocks of memory. Since the card > requires DMA-addresses of that memory, the driver provides two ways to > solve that task: > 1) The drivers mmap() will allocate some DMAable memory for the user. > The driver has a lookup table such that the virtual userspace > address can properly be replaced and checked. > 2) The user allocates memory and the driver will pin/unpin that > memory and setup a scatter gatherlist with matching DMA addresses. > > Currently work requests are synchronous. > > The genwqe driver has a user-space interface described in > linux/include/genwqe/genwqe_card.h. There are several ioctls which can > be used to talk to the driver. In addition there are some sysfs > entries where information can be exchanged with user-space. > > Known Restrictions: > > o On my PowerPC testsystem SRIOV did not work. Does this restriction still apply? Is there some PCI core issue here? We did fix an SR-IOV issue that was reported on PowerPC with aa914f5ec25, so maybe that's related. But if there's still a PCI core issue here, let me know. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/