Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752591AbYLUXGt (ORCPT ); Sun, 21 Dec 2008 18:06:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751258AbYLUXGk (ORCPT ); Sun, 21 Dec 2008 18:06:40 -0500 Received: from mail.work.de ([212.12.32.20]:58568 "EHLO mail.work.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751016AbYLUXGj (ORCPT ); Sun, 21 Dec 2008 18:06:39 -0500 Message-ID: <494ECBC5.1040703@gmail.com> Date: Mon, 22 Dec 2008 03:05:41 +0400 From: Manu Abraham User-Agent: Thunderbird 1.5.0.14ubu (X11/20080306) MIME-Version: 1.0 To: michael@ellerman.id.au CC: Grant Grundler , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: MSI messages References: <49438290.1080502@gmail.com> <20081214081210.GC13371@colo.lackof.org> <4944EAC3.1020407@gmail.com> <20081214185239.GA2039@colo.lackof.org> <494D5FF7.50807@gmail.com> <1229897516.8269.8.camel@localhost> In-Reply-To: <1229897516.8269.8.camel@localhost> X-Enigmail-Version: 0.94.0.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5132 Lines: 77 Michael Ellerman wrote: > On Sun, 2008-12-21 at 01:13 +0400, Manu Abraham wrote: >> Grant Grundler wrote: >>> On Sun, Dec 14, 2008 at 03:15:15PM +0400, Manu Abraham wrote: >>> ... >>>>> A "GSI" (Generic Sys Interrupt?) is associated with each entry in >>>>> the MSI-X table. Driver then calls request_irq() to bind an interrupt >>>>> handler to each GSI. So the driver never directly sees the "message". >>>> Oh, you mean the array of irq_handlers in the MSI-X table should >>>> correspond to a particular message ? >>> No. I mean each MSI-X entry has an address+message pair and each MSI-X entry >>> is associated with the parameters passed to each call of request_irq(). >>> Pass in unique private data to each call of request_irq() and the driver >>> can determine which message was delivered when the ISR gets called. >>> (ISR == Interrupt Service Routine, aka driver IRQ handler) >> >> Is it possible that even when the config space says that multiple messages >> are supported, you cannot enable MSI-X ? > > Yes, absolutely. Have a look at pci_msi_check_device() for starters. MSI > can be disabled globally, or per-device by a quirk, the bridges above > your device might not support MSI and the arch code may prevent > MSI/MSI-X for some reason (ie. platform doesn't support it). It seems that the bridge does support MSI. It looks like my video device is using MSI. Regards, Manu pci 0000:01:00.0: Boot video device PCI: Setting latency timer of device 0000:00:01.0 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:01.0:pcie00] PCI: Setting latency timer of device 0000:00:1c.0 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:1c.0:pcie00] Allocate Port Service[0000:00:1c.0:pcie02] PCI: Setting latency timer of device 0000:00:1c.1 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:1c.1:pcie00] Allocate Port Service[0000:00:1c.1:pcie02] PCI: Setting latency timer of device 0000:00:1c.2 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:1c.2:pcie00] Allocate Port Service[0000:00:1c.2:pcie02] PCI: Setting latency timer of device 0000:00:1c.3 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:1c.3:pcie00] Allocate Port Service[0000:00:1c.3:pcie02] PCI: Setting latency timer of device 0000:00:1c.4 to 64 assign_interrupt_mode Found MSI capability Allocate Port Service[0000:00:1c.4:pcie00] Allocate Port Service[0000:00:1c.4:pcie02] vesafb: framebuffer at 0x91000000, mapped to 0xf8880000, using 10240k, total 14336k vesafb: mode is 1280x1024x16, linelength=2560, pages=1 04:00.0 Multimedia controller: Philips Semiconductors Device 7160 (rev 02) Subsystem: Technotrend Systemtechnik GmbH Device 3009 Flags: bus master, fast devsel, latency 0, IRQ 11 Memory at 93b00000 (64-bit, non-prefetchable) [size=1M] Capabilities: 05:00.0 Multimedia controller: Philips Semiconductors Device 7160 (rev 01) Subsystem: Philips Semiconductors Device 0000 Flags: bus master, fast devsel, latency 0, IRQ 19 Memory at 93a00000 (64-bit, non-prefetchable) [size=1M] Capabilities: Kernel driver in use: SAA716x Hybrid -- 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/