Re: [Xen-devel] [PATCH v6 07/30] PCI: Pass PCI domain number combined with root bus number

[Manish Jaggi <mjaggi@caviumnetworks.com>]

On Monday 09 March 2015 08:04 AM, Yijing Wang wrote:
> Now we could pass PCI domain combined with bus number
> in u32 argu. Because in arm/arm64, PCI domain number
> is assigned by pci_bus_assign_domain_nr(). So we leave
> pci_scan_root_bus() and pci_create_root_bus() in arm/arm64
> unchanged. A new function pci_host_assign_domain_nr()
> will be introduced for arm/arm64 to assign domain number
> in later patch.
Hi,
I think these changes might not be required. We have made very few 
changes in the xen-pcifront to support PCI passthrough in arm64.
As per xen architecture for a domU only a single pci virtual bus is 
created and all passthrough devices are attached to it.


-manish
>
> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
> CC: Richard Henderson <rth@twiddle.net>
> CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
> CC: Matt Turner <mattst88@gmail.com>
> CC: Tony Luck <tony.luck@intel.com>
> CC: Fenghua Yu <fenghua.yu@intel.com>
> CC: Michal Simek <monstr@monstr.eu>
> CC: Ralf Baechle <ralf@linux-mips.org>
> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> CC: Paul Mackerras <paulus@samba.org>
> CC: Michael Ellerman <mpe@ellerman.id.au>
> CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
> CC: Gerald Schaefer <gerald.schaefer@de.ibm.com>
> CC: "David S. Miller" <davem@davemloft.net>
> CC: Chris Metcalf <cmetcalf@ezchip.com>
> CC: Thomas Gleixner <tglx@linutronix.de>
> CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> CC: linux-alpha@vger.kernel.org
> CC: linux-kernel@vger.kernel.org
> CC: linux-ia64@vger.kernel.org
> CC: linux-mips@linux-mips.org
> CC: linuxppc-dev@lists.ozlabs.org
> CC: linux-s390@vger.kernel.org
> CC: linux-sh@vger.kernel.org
> CC: sparclinux@vger.kernel.org
> CC: xen-devel@lists.xenproject.org
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> ---
>   arch/alpha/kernel/pci.c          |    5 +++--
>   arch/alpha/kernel/sys_nautilus.c |    4 ++--
>   arch/ia64/pci/pci.c              |    4 ++--
>   arch/ia64/sn/kernel/io_init.c    |    5 +++--
>   arch/microblaze/pci/pci-common.c |    5 +++--
>   arch/mips/pci/pci.c              |    4 ++--
>   arch/powerpc/kernel/pci-common.c |    5 +++--
>   arch/s390/pci/pci.c              |    5 +++--
>   arch/sh/drivers/pci/pci.c        |    5 +++--
>   arch/sparc/kernel/pci.c          |    5 +++--
>   arch/tile/kernel/pci.c           |    5 +++--
>   arch/tile/kernel/pci_gx.c        |    5 +++--
>   arch/x86/pci/acpi.c              |    7 ++++---
>   arch/x86/pci/common.c            |    3 ++-
>   drivers/pci/xen-pcifront.c       |    5 +++--
>   15 files changed, 42 insertions(+), 30 deletions(-)
>
> diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
> index 5c845ad..deb0a36 100644
> --- a/arch/alpha/kernel/pci.c
> +++ b/arch/alpha/kernel/pci.c
> @@ -336,8 +336,9 @@ common_init_pci(void)
>   		pci_add_resource_offset(&resources, hose->mem_space,
>   					hose->mem_space->start);
>   
> -		bus = pci_scan_root_bus(NULL, next_busno, alpha_mv.pci_ops,
> -					hose, &resources);
> +		bus = pci_scan_root_bus(NULL,
> +				PCI_DOMBUS(hose->index, next_busno),
> +				alpha_mv.pci_ops, hose, &resources);
>   		if (!bus)
>   			continue;
>   		hose->bus = bus;
> diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c
> index 700686d..be0bbeb 100644
> --- a/arch/alpha/kernel/sys_nautilus.c
> +++ b/arch/alpha/kernel/sys_nautilus.c
> @@ -206,10 +206,10 @@ nautilus_init_pci(void)
>   	unsigned long memtop = max_low_pfn << PAGE_SHIFT;
>   
>   	/* Scan our single hose.  */
> -	bus = pci_scan_bus(0, alpha_mv.pci_ops, hose);
> +	bus = pci_scan_bus(PCI_DOMBUS(hose->index, 0),
> +			alpha_mv.pci_ops, hose);
>   	if (!bus)
>   		return;
> -
>   	hose->bus = bus;
>   	pcibios_claim_one_bus(bus);
>   
> diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
> index 48cc657..675749f 100644
> --- a/arch/ia64/pci/pci.c
> +++ b/arch/ia64/pci/pci.c
> @@ -465,8 +465,8 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>   	 * should handle the case here, but it appears that IA64 hasn't
>   	 * such quirk. So we just ignore the case now.
>   	 */
> -	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops, controller,
> -				   &info->resources);
> +	pbus = pci_create_root_bus(NULL, PCI_DOMBUS(domain, bus),
> +			&pci_root_ops, controller, &info->resources);
>   	if (!pbus) {
>   		pci_free_resource_list(&info->resources);
>   		__release_pci_root_info(info);
> diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
> index 1be65eb..7e0b7f9 100644
> --- a/arch/ia64/sn/kernel/io_init.c
> +++ b/arch/ia64/sn/kernel/io_init.c
> @@ -266,8 +266,9 @@ sn_pci_controller_fixup(int segment, int busnum, struct pci_bus *bus)
>   	pci_add_resource_offset(&resources,	&res[1],
>   			prom_bussoft_ptr->bs_legacy_mem);
>   
> -	bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, controller,
> -				&resources);
> +	bus = pci_scan_root_bus(NULL,
> +			PCI_DOMBUS(controller->segment, busnum),
> +			&pci_root_ops, controller, &resources);
>    	if (bus == NULL) {
>   		kfree(res);
>   		kfree(controller);
> diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
> index 6d8d173..34a32ec 100644
> --- a/arch/microblaze/pci/pci-common.c
> +++ b/arch/microblaze/pci/pci-common.c
> @@ -1350,8 +1350,9 @@ static void pcibios_scan_phb(struct pci_controller *hose)
>   
>   	pcibios_setup_phb_resources(hose, &resources);
>   
> -	bus = pci_scan_root_bus(hose->parent, hose->first_busno,
> -				hose->ops, hose, &resources);
> +	bus = pci_scan_root_bus(hose->parent,
> +			PCI_DOMBUS(hose->global_number, hose->first_busno),
> +			hose->ops, hose, &resources);
>   	if (bus == NULL) {
>   		pr_err("Failed to create bus for PCI domain %04x\n",
>   		       hose->global_number);
> diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
> index 9eb54b5..86f8d2b 100644
> --- a/arch/mips/pci/pci.c
> +++ b/arch/mips/pci/pci.c
> @@ -92,8 +92,8 @@ static void pcibios_scanbus(struct pci_controller *hose)
>   	pci_add_resource_offset(&resources,
>   				hose->mem_resource, hose->mem_offset);
>   	pci_add_resource_offset(&resources, hose->io_resource, hose->io_offset);
> -	bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
> -				&resources);
> +	bus = pci_scan_root_bus(NULL, PCI_DOMBUS(hose->index, next_busno),
> +			hose->pci_ops, hose, &resources);
>   	if (!bus)
>   		pci_free_resource_list(&resources);
>   
> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
> index 2a525c9..a467aca 100644
> --- a/arch/powerpc/kernel/pci-common.c
> +++ b/arch/powerpc/kernel/pci-common.c
> @@ -1612,8 +1612,9 @@ void pcibios_scan_phb(struct pci_controller *hose)
>   	pci_add_resource(&resources, &hose->busn);
>   
>   	/* Create an empty bus for the toplevel */
> -	bus = pci_create_root_bus(hose->parent, hose->first_busno,
> -				  hose->ops, hose, &resources);
> +	bus = pci_create_root_bus(hose->parent,
> +			PCI_DOMBUS(hose->global_number, hose->first_busno),
> +			hose->ops, hose, &resources);
>   	if (bus == NULL) {
>   		pr_err("Failed to create bus for PCI domain %04x\n",
>   			hose->global_number);
> diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
> index a2a7391..20e662f 100644
> --- a/arch/s390/pci/pci.c
> +++ b/arch/s390/pci/pci.c
> @@ -770,8 +770,9 @@ static int zpci_scan_bus(struct zpci_dev *zdev)
>   	if (ret)
>   		return ret;
>   
> -	zdev->bus = pci_scan_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops,
> -				      zdev, &resources);
> +	zdev->bus = pci_scan_root_bus(NULL,
> +			PCI_DOMBUS(zdev->domain, ZPCI_BUS_NR), &pci_root_ops,
> +			zdev, &resources);
>   	if (!zdev->bus) {
>   		zpci_cleanup_bus_resources(zdev);
>   		return -EIO;
> diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
> index efc1051..116f80f 100644
> --- a/arch/sh/drivers/pci/pci.c
> +++ b/arch/sh/drivers/pci/pci.c
> @@ -52,8 +52,9 @@ static void pcibios_scanbus(struct pci_channel *hose)
>   		pci_add_resource_offset(&resources, res, offset);
>   	}
>   
> -	bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
> -				&resources);
> +	bus = pci_scan_root_bus(NULL,
> +			PCI_DOMBUS(hose->index, next_busno),
> +			hose->pci_ops, hose, &resources);
>   	hose->bus = bus;
>   
>   	need_domain_info = need_domain_info || hose->index;
> diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
> index 9ce5afe..838fe1e 100644
> --- a/arch/sparc/kernel/pci.c
> +++ b/arch/sparc/kernel/pci.c
> @@ -667,8 +667,9 @@ struct pci_bus *pci_scan_one_pbm(struct pci_pbm_info *pbm,
>   	pbm->busn.end	= pbm->pci_last_busno;
>   	pbm->busn.flags	= IORESOURCE_BUS;
>   	pci_add_resource(&resources, &pbm->busn);
> -	bus = pci_create_root_bus(parent, pbm->pci_first_busno, pbm->pci_ops,
> -				  pbm, &resources);
> +	bus = pci_create_root_bus(parent,
> +			PCI_DOMBUS(pbm->index, pbm->pci_first_busno),
> +			pbm->pci_ops, pbm, &resources);
>   	if (!bus) {
>   		printk(KERN_ERR "Failed to create bus for %s\n",
>   		       node->full_name);
> diff --git a/arch/tile/kernel/pci.c b/arch/tile/kernel/pci.c
> index 9475a74..25b0d9b 100644
> --- a/arch/tile/kernel/pci.c
> +++ b/arch/tile/kernel/pci.c
> @@ -306,8 +306,9 @@ int __init pcibios_init(void)
>   
>   			pci_add_resource(&resources, &ioport_resource);
>   			pci_add_resource(&resources, &iomem_resource);
> -			bus = pci_scan_root_bus(NULL, 0, controller->ops,
> -						controller, &resources);
> +			bus = pci_scan_root_bus(NULL,
> +				PCI_DOMBUS(controller->index, 0),
> +				controller->ops, controller, &resources);
>   			controller->root_bus = bus;
>   			controller->last_busno = bus->busn_res.end;
>   		}
> diff --git a/arch/tile/kernel/pci_gx.c b/arch/tile/kernel/pci_gx.c
> index b1df847..f6f41f3 100644
> --- a/arch/tile/kernel/pci_gx.c
> +++ b/arch/tile/kernel/pci_gx.c
> @@ -881,8 +881,9 @@ int __init pcibios_init(void)
>   					controller->mem_offset);
>   		pci_add_resource(&resources, &controller->io_space);
>   		controller->first_busno = next_busno;
> -		bus = pci_scan_root_bus(NULL, next_busno, controller->ops,
> -					controller, &resources);
> +		bus = pci_scan_root_bus(NULL,
> +				PCI_DOMBUS(controller->index, next_busno),
> +				controller->ops, controller, &resources);
>   		controller->root_bus = bus;
>   		next_busno = bus->busn_res.end + 1;
>   	}
> diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
> index 6ac2738..ad0e926 100644
> --- a/arch/x86/pci/acpi.c
> +++ b/arch/x86/pci/acpi.c
> @@ -424,9 +424,10 @@ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
>   		}
>   
>   		if (!setup_mcfg_map(info, domain, (u8)root->secondary.start,
> -				    (u8)root->secondary.end, root->mcfg_addr))
> -			bus = pci_create_root_bus(NULL, busnum, &pci_root_ops,
> -						  sd, &resources);
> +				(u8)root->secondary.end, root->mcfg_addr))
> +			bus = pci_create_root_bus(NULL,
> +				PCI_DOMBUS(domain, busnum), &pci_root_ops,
> +				sd, &resources);
>   
>   		if (bus) {
>   			pci_scan_child_bus(bus);
> diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
> index 0cbc723..0160280 100644
> --- a/arch/x86/pci/common.c
> +++ b/arch/x86/pci/common.c
> @@ -486,7 +486,8 @@ void pcibios_scan_root(int busnum)
>   	sd->node = x86_pci_root_bus_node(busnum);
>   	x86_pci_root_bus_resources(busnum, &resources);
>   	printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
> -	bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, sd, &resources);
> +	bus = pci_scan_root_bus(NULL, PCI_DOMBUS(0, busnum),
> +			&pci_root_ops, sd, &resources);
>   	if (!bus) {
>   		pci_free_resource_list(&resources);
>   		kfree(sd);
> diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
> index 9e7c28b..af6144a 100644
> --- a/drivers/pci/xen-pcifront.c
> +++ b/drivers/pci/xen-pcifront.c
> @@ -479,8 +479,9 @@ static int pcifront_scan_root(struct pcifront_device *pdev,
>   
>   	pci_lock_rescan_remove();
>   
> -	b = pci_scan_root_bus(&pdev->xdev->dev, bus,
> -				  &pcifront_bus_ops, sd, &resources);
> +	b = pci_scan_root_bus(&pdev->xdev->dev,
> +			PCI_DOMBUS(sd->domain, bus),
> +			&pcifront_bus_ops, sd, &resources);
>   	if (!b) {
>   		dev_err(&pdev->xdev->dev,
>   			"Error creating PCI Frontend Bus!\n");