Commit cca87d30 authored by Gavin Shan's avatar Gavin Shan Committed by Benjamin Herrenschmidt
Browse files

powerpc/pci: Refactor pci_dn 



Currently, the PCI config accessors are implemented based on device node.
Unfortunately, SRIOV VFs won't have the corresponding device nodes. pci_dn
will be used in replacement with device node for SRIOV VFs. So we have to
use pci_dn in PCI config accessors.

The patch refactors pci_dn in following aspects to make it ready to be used
in PCI config accessors as we do in subsequent patch:

   * pci_dn is organized as a hierarchy tree.  PCI device's pci_dn is
     put to the child list of pci_dn of its upstream bridge or PHB. VF's
     pci_dn will be put to the child list of pci_dn of PF's bridge.

   * For one particular PCI device (VF or not), its pci_dn can be
     found from pdev->dev.archdata.pci_data, PCI_DN(devnode), or
     parent's list.  The fast path (fetching pci_dn through PCI device
     instance) is populated during early fixup time.

[bhelgaas: changelog]
Signed-off-by: default avatarGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 12a89dba

arch/powerpc/include/asm/device.h

+6 −0
Original line number Diff line number Diff line
@@ -8,6 +8,9 @@ 


struct dma_map_ops;

struct device_node;

#ifdef CONFIG_PPC64

struct pci_dn;

#endif



/*

 * Arch extensions to struct device.
@@ -34,6 +37,9 @@ struct dev_archdata { 
#ifdef CONFIG_SWIOTLB

	dma_addr_t		max_direct_dma_addr;

#endif

#ifdef CONFIG_PPC64

	struct pci_dn		*pci_data;

#endif

#ifdef CONFIG_EEH

	struct eeh_dev		*edev;

#endif

arch/powerpc/include/asm/pci-bridge.h

+9 −2
Original line number Diff line number Diff line
@@ -89,6 +89,7 @@ struct pci_controller { 


#ifdef CONFIG_PPC64

	unsigned long buid;

	struct pci_dn *pci_data;

#endif	/* CONFIG_PPC64 */



	void *private_data;
@@ -154,9 +155,12 @@ static inline int isa_vaddr_is_ioport(void __iomem *address) 
struct iommu_table;



struct pci_dn {

	int     flags;



	int	busno;			/* pci bus number */

	int	devfn;			/* pci device and function number */



	struct  pci_dn *parent;

	struct  pci_controller *phb;	/* for pci devices */

	struct	iommu_table *iommu_table;	/* for phb's or bridges */

	struct	device_node *node;	/* back-pointer to the device_node */
@@ -171,13 +175,16 @@ struct pci_dn { 
#ifdef CONFIG_PPC_POWERNV

	int	pe_number;

#endif

	struct list_head child_list;

	struct list_head list;

};



/* Get the pointer to a device_node's pci_dn */

#define PCI_DN(dn)	((struct pci_dn *) (dn)->data)



extern struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,

					   int devfn);

extern struct pci_dn *pci_get_pdn(struct pci_dev *pdev);



extern void *update_dn_pci_info(struct device_node *dn, void *data);



static inline int pci_device_from_OF_node(struct device_node *np,

arch/powerpc/kernel/pci_dn.c

+126 −4
Original line number Diff line number Diff line
@@ -32,12 +32,108 @@ 
#include <asm/ppc-pci.h>

#include <asm/firmware.h>



/*

 * The function is used to find the firmware data of one

 * specific PCI device, which is attached to the indicated

 * PCI bus. For VFs, their firmware data is linked to that

 * one of PF's bridge. For other devices, their firmware

 * data is linked to that of their bridge.

 */

static struct pci_dn *pci_bus_to_pdn(struct pci_bus *bus)

{

	struct pci_bus *pbus;

	struct device_node *dn;

	struct pci_dn *pdn;



	/*

	 * We probably have virtual bus which doesn't

	 * have associated bridge.

	 */

	pbus = bus;

	while (pbus) {

		if (pci_is_root_bus(pbus) || pbus->self)

			break;



		pbus = pbus->parent;

	}



	/*

	 * Except virtual bus, all PCI buses should

	 * have device nodes.

	 */

	dn = pci_bus_to_OF_node(pbus);

	pdn = dn ? PCI_DN(dn) : NULL;



	return pdn;

}



struct pci_dn *pci_get_pdn_by_devfn(struct pci_bus *bus,

				    int devfn)

{

	struct device_node *dn = NULL;

	struct pci_dn *parent, *pdn;

	struct pci_dev *pdev = NULL;



	/* Fast path: fetch from PCI device */

	list_for_each_entry(pdev, &bus->devices, bus_list) {

		if (pdev->devfn == devfn) {

			if (pdev->dev.archdata.pci_data)

				return pdev->dev.archdata.pci_data;



			dn = pci_device_to_OF_node(pdev);

			break;

		}

	}



	/* Fast path: fetch from device node */

	pdn = dn ? PCI_DN(dn) : NULL;

	if (pdn)

		return pdn;



	/* Slow path: fetch from firmware data hierarchy */

	parent = pci_bus_to_pdn(bus);

	if (!parent)

		return NULL;



	list_for_each_entry(pdn, &parent->child_list, list) {

		if (pdn->busno == bus->number &&

                    pdn->devfn == devfn)

                        return pdn;

        }



	return NULL;

}



struct pci_dn *pci_get_pdn(struct pci_dev *pdev)

{

	struct device_node *dn = pci_device_to_OF_node(pdev);

	if (!dn)

	struct device_node *dn;

	struct pci_dn *parent, *pdn;



	/* Search device directly */

	if (pdev->dev.archdata.pci_data)

		return pdev->dev.archdata.pci_data;



	/* Check device node */

	dn = pci_device_to_OF_node(pdev);

	pdn = dn ? PCI_DN(dn) : NULL;

	if (pdn)

		return pdn;



	/*

	 * VFs don't have device nodes. We hook their

	 * firmware data to PF's bridge.

	 */

	parent = pci_bus_to_pdn(pdev->bus);

	if (!parent)

		return NULL;



	list_for_each_entry(pdn, &parent->child_list, list) {

		if (pdn->busno == pdev->bus->number &&

		    pdn->devfn == pdev->devfn)

			return pdn;

	}



	return NULL;

	return PCI_DN(dn);

}



/*
@@ -49,6 +145,7 @@ void *update_dn_pci_info(struct device_node *dn, void *data) 
	struct pci_controller *phb = data;

	const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);

	const __be32 *regs;

	struct device_node *parent;

	struct pci_dn *pdn;



	pdn = zalloc_maybe_bootmem(sizeof(*pdn), GFP_KERNEL);
@@ -70,6 +167,15 @@ void *update_dn_pci_info(struct device_node *dn, void *data) 
	}



	pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);



	/* Attach to parent node */

	INIT_LIST_HEAD(&pdn->child_list);

	INIT_LIST_HEAD(&pdn->list);

	parent = of_get_parent(dn);

	pdn->parent = parent ? PCI_DN(parent) : NULL;

	if (pdn->parent)

		list_add_tail(&pdn->list, &pdn->parent->child_list);



	return NULL;

}
@@ -147,8 +253,11 @@ void pci_devs_phb_init_dynamic(struct pci_controller *phb) 
	/* PHB nodes themselves must not match */

	update_dn_pci_info(dn, phb);

	pdn = dn->data;

	if (pdn)

	if (pdn) {

		pdn->devfn = pdn->busno = -1;

		pdn->phb = phb;

		phb->pci_data = pdn;

	}



	/* Update dn->phb ptrs for new phb and children devices */

	traverse_pci_devices(dn, update_dn_pci_info, phb);
@@ -171,3 +280,16 @@ void __init pci_devs_phb_init(void) 
	list_for_each_entry_safe(phb, tmp, &hose_list, list_node)

		pci_devs_phb_init_dynamic(phb);

}



static void pci_dev_pdn_setup(struct pci_dev *pdev)

{

	struct pci_dn *pdn;



	if (pdev->dev.archdata.pci_data)

		return;



	/* Setup the fast path */

	pdn = pci_get_pdn(pdev);

	pdev->dev.archdata.pci_data = pdn;

}

DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, pci_dev_pdn_setup);

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