From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from service87.mimecast.com ([91.220.42.44]:51157 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751208AbaJAIqb convert rfc822-to-8bit (ORCPT ); Wed, 1 Oct 2014 04:46:31 -0400 Date: Wed, 1 Oct 2014 09:46:26 +0100 From: Liviu Dudau To: Arnd Bergmann Cc: "linux-arm-kernel@lists.infradead.org" , Mark Rutland , "devicetree@vger.kernel.org" , Lorenzo Pieralisi , "jason@lakedaemon.net" , "linux-doc@vger.kernel.org" , Marc Zyngier , "linux-pci@vger.kernel.org" , Will Deacon , "linux-kernel@vger.kernel.org" , "robh+dt@kernel.org" , "suravee.suthikulpanit@amd.com" , Catalin Marinas , "bhelgaas@google.com" , "tglx@linutronix.de" Subject: Re: [RFC 2/4] PCI: generic: Add support for ARM64 and MSI(x) Message-ID: <20141001084626.GZ841@e106497-lin.cambridge.arm.com> References: <1411937610-22125-1-git-send-email-suravee.suthikulpanit@amd.com> <20140930174821.GX841@e106497-lin.cambridge.arm.com> <3079787.54pZijGjZM@wuerfel> <2430078.s4snyh5OoF@wuerfel> MIME-Version: 1.0 In-Reply-To: <2430078.s4snyh5OoF@wuerfel> Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On Tue, Sep 30, 2014 at 09:01:14PM +0100, Arnd Bergmann wrote: > On Tuesday 30 September 2014 20:54:41 Arnd Bergmann wrote: > > On Tuesday 30 September 2014 18:48:21 Liviu Dudau wrote: > > > > > > > These are the functions I found that refer to pci_sys_data on arm32: > > > > > > > > > > > > > > pcibios_add_bus > > > > > > > pcibios_remove_bus > > > > > > These are only needed if you want to do per HB processing of the bus > > > > > > > > > > pcibios_align_resource > > > > > > mvebu is the only user of this function. > > > > > > > > > > pci_mmap_page_range > > > > > > This is only needed when mapping a PCI resource to userspace. Is that your case here? > > > > > > > > > > pci_domain_nr > > > > > > > pci_proc_domain > > > > > > We have equivalent functionality in the generic patches for those. > > > > > > > We clearly don't need those functions for the new drivers, but that's not > > the point. The problem is that when you build a kernel that has both > > a traditional host bridge driver and a new one in it, you always get those > > functions and they get called from the PCI core, with incorrect arguments. > > FWIW, the last time we discussed this, I think I had suggested that the > functions that are currently architecture specific and have a generic > __weak fallback could become function pointers in a per-host structure > passed to pci_scan_root_bus, either a new structure or an extended > struct pci_ops. Something along these lines: Agree to the general idea. But have a look why host drivers need the add_bus ops: to add MSI information into the bus!! If we take care of the MSI in the generic code there is less of a need for this function at all. Best regards, Liviu > > diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h > index 7fc42784becb..3da32fc631d0 100644 > --- a/arch/arm/include/asm/mach/pci.h > +++ b/arch/arm/include/asm/mach/pci.h > @@ -36,7 +36,6 @@ struct hw_pci { > resource_size_t start, > resource_size_t size, > resource_size_t align); > - void (*add_bus)(struct pci_bus *bus); > void (*remove_bus)(struct pci_bus *bus); > }; > > @@ -65,7 +64,6 @@ struct pci_sys_data { > resource_size_t start, > resource_size_t size, > resource_size_t align); > - void (*add_bus)(struct pci_bus *bus); > void (*remove_bus)(struct pci_bus *bus); > void *private_data; /* platform controller private data */ > }; > diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c > index 17a26c17f7f5..3cbcf8dc41e4 100644 > --- a/arch/arm/kernel/bios32.c > +++ b/arch/arm/kernel/bios32.c > @@ -360,13 +360,6 @@ void pcibios_fixup_bus(struct pci_bus *bus) > } > EXPORT_SYMBOL(pcibios_fixup_bus); > > -void pcibios_add_bus(struct pci_bus *bus) > -{ > - struct pci_sys_data *sys = bus->sysdata; > - if (sys->add_bus) > - sys->add_bus(bus); > -} > - > void pcibios_remove_bus(struct pci_bus *bus) > { > struct pci_sys_data *sys = bus->sysdata; > @@ -475,7 +468,6 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, > sys->swizzle = hw->swizzle; > sys->map_irq = hw->map_irq; > sys->align_resource = hw->align_resource; > - sys->add_bus = hw->add_bus; > sys->remove_bus = hw->remove_bus; > INIT_LIST_HEAD(&sys->resources); > > diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c > index b1315e197ffb..c9a0ee0429e8 100644 > --- a/drivers/pci/host/pci-mvebu.c > +++ b/drivers/pci/host/pci-mvebu.c > @@ -716,6 +716,7 @@ static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where, > static struct pci_ops mvebu_pcie_ops = { > .read = mvebu_pcie_rd_conf, > .write = mvebu_pcie_wr_conf, > + .add_bus = mvebu_pcie_add_bus, > }; > > static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys) > @@ -823,7 +824,6 @@ static void mvebu_pcie_enable(struct mvebu_pcie *pcie) > hw.map_irq = of_irq_parse_and_map_pci; > hw.ops = &mvebu_pcie_ops; > hw.align_resource = mvebu_pcie_align_resource; > - hw.add_bus = mvebu_pcie_add_bus; > > pci_common_init(&hw); > } > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index a63a47a70846..be6d56358320 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -1885,6 +1885,8 @@ int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) > > void __weak pcibios_add_bus(struct pci_bus *bus) > { > + if (bus->ops && bus->ops->add_bus) > + bus->ops->add_bus(bus); > } > > void __weak pcibios_remove_bus(struct pci_bus *bus) > > Arnd > > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯