From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bn1lp0141.outbound.protection.outlook.com ([207.46.163.141]:11701 "EHLO na01-bn1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750745AbaHTHl7 convert rfc822-to-8bit (ORCPT ); Wed, 20 Aug 2014 03:41:59 -0400 From: "Bharat.Bhushan@freescale.com" To: Yijing Wang , "arnab.basu@freescale.com" CC: Xinwei Hu , Wuyun , "Bjorn Helgaas" , "linux-pci@vger.kernel.org" , "Paul.Mundt@huawei.com" , "James E.J. Bottomley" , Marc Zyngier , "linux-arm-kernel@lists.infradead.org" , Russell King , "linux-arch@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , Hanjun Guo , "linux-kernel@vger.kernel.org" Subject: RE: [RFC PATCH 00/11] Refactor MSI to support Non-PCI device Date: Wed, 20 Aug 2014 07:41:55 +0000 Message-ID: References: <1406344128-27055-1-git-send-email-wangyijing@huawei.com> <53DEF80C.1010608@huawei.com> <8a2b4e237f2d4c7e95ef72867658b53a@BLUPR03MB566.namprd03.prod.outlook.com> <53F44022.6030706@huawei.com> In-Reply-To: <53F44022.6030706@huawei.com> Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org List-ID: > -----Original Message----- > From: linux-pci-owner@vger.kernel.org [mailto:linux-pci-owner@vger.kernel.org] > On Behalf Of Yijing Wang > Sent: Wednesday, August 20, 2014 11:59 AM > To: Bhushan Bharat-R65777; Basu Arnab-B45036 > Cc: Xinwei Hu; Wuyun; Bjorn Helgaas; linux-pci@vger.kernel.org; > Paul.Mundt@huawei.com; James E.J. Bottomley; Marc Zyngier; linux-arm- > kernel@lists.infradead.org; Russell King; linux-arch@vger.kernel.org; > virtualization@lists.linux-foundation.org; Hanjun Guo; linux- > kernel@vger.kernel.org > Subject: Re: [RFC PATCH 00/11] Refactor MSI to support Non-PCI device > > >> The key difference between PCI device and Non-PCI MSI is the > >> interfaces to access hardware MSI registers. > >> for instance, currently, msi_chip->setup_irq() to setup MSI irq and > >> configure the MSI address/data registers, so we need to provide > >> device specific > >> write_msi_msg() interface, then when we call msi_chip->setup_irq(), > >> the device MSI registers can be configured appropriately. > > > > What if we can register/override the setup_irq() from bus-driver (not sure, > but may be device-driver itself). Example PCI bus-driver will provide > setup_irq() (or the part of setup_irq which set address and data in h/w) by PCI > bus, which configure address/data in h/w as per PCI standard. > > > > We in Freescale will be using MSI for the devices behind a new-bus (which is > not PCI based), We have a separate bus driver for same. And this new bus driver > register/provide its own address/data write function which is based on that > specific bus protocol. > > Hi Bharat, I'm glad to know your MSI device working mode. > Provide the private MSI setup functions in bus-driver layer can't apply to all > Non-PCI MSI devices, because we can not guarantee Non-PCI MSI devices are always > on a bus. The existing HPET, DMAR device both have no bus bind. Yes, that's why I was not sure of bus-driver or device-driver model. > I'm working on a > new MSI setup framework, as you mentioned before, in device-driver model. > > I abstracted a new virtual device (called struct msi_dev), this msi_dev will > manage all MSI info, Will this "struct msi_dev" will be part of "struct device"? > and a new bus named msi_bus, also introduced a new driver > msi_driver, msi_bus is responsible for binding msi_dev and msi_driver. > All MSI devices will be classified into different MSI device types, like > MSI_TYPE_PCI, MSI_TYPE_HPET, MSI_TYPE_DMAR, etc.. > > Each MSI type device should provide a private struct msi_driver. msi_driver > should contain the type specific MSI ops functions to help setup and enable MSI > device, request MSI irq. > > I almost finish the first draft, and will post out next week in plan :) Will be looking forward to next version. Thanks -Bharat > > > Thanks! > Yijing. > > > > > Thanks > > -Bharat > > > >> > >> My patchset is just a RFC draft, I will update it later, all we want > >> to do is make kernel support Non-PCI MSI devices. > >> > >> Thanks! > >> Yijing. > >> > >> > >>> > >>> Thanks > >>> Arnab > >>> -- > >>> 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/ > >>> > >>> . > >>> > >> > >> > >> -- > >> Thanks! > >> Yijing > >> > >> -- > >> To unsubscribe from this list: send the line "unsubscribe linux-pci" > >> in the body of a message to majordomo@vger.kernel.org More majordomo > >> info at http://vger.kernel.org/majordomo-info.html > > > > . > > > > > -- > Thanks! > Yijing > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body > of a message to majordomo@vger.kernel.org More majordomo info at > http://vger.kernel.org/majordomo-info.html