1 files changed, 496 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c
new file mode 100644
index 0000000000..38561d6a20
--- /dev/null
+++ b/arch/powerpc/kernel/pci_dn.c
@@ -0,0 +1,496 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * pci_dn.c
+ *
+ * Copyright (C) 2001 Todd Inglett, IBM Corporation
+ *
+ * PCI manipulation via device_nodes.
+ */
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <linux/of.h>
+
+#include <asm/io.h>
+#include <asm/pci-bridge.h>
+#include <asm/ppc-pci.h>
+#include <asm/firmware.h>
+#include <asm/eeh.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;
+	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;
+}
+
+#ifdef CONFIG_EEH
+static struct eeh_dev *eeh_dev_init(struct pci_dn *pdn)
+{
+	struct eeh_dev *edev;
+
+	/* Allocate EEH device */
+	edev = kzalloc(sizeof(*edev), GFP_KERNEL);
+	if (!edev)
+		return NULL;
+
+	/* Associate EEH device with OF node */
+	pdn->edev = edev;
+	edev->pdn = pdn;
+	edev->bdfn = (pdn->busno << 8) | pdn->devfn;
+	edev->controller = pdn->phb;
+
+	return edev;
+}
+#endif /* CONFIG_EEH */
+
+#ifdef CONFIG_PCI_IOV
+static struct pci_dn *add_one_sriov_vf_pdn(struct pci_dn *parent,
+					   int busno, int devfn)
+{
+	struct pci_dn *pdn;
+
+	/* Except PHB, we always have the parent */
+	if (!parent)
+		return NULL;
+
+	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
+	if (!pdn)
+		return NULL;
+
+	pdn->phb = parent->phb;
+	pdn->parent = parent;
+	pdn->busno = busno;
+	pdn->devfn = devfn;
+	pdn->pe_number = IODA_INVALID_PE;
+	INIT_LIST_HEAD(&pdn->child_list);
+	INIT_LIST_HEAD(&pdn->list);
+	list_add_tail(&pdn->list, &parent->child_list);
+
+	return pdn;
+}
+
+struct pci_dn *add_sriov_vf_pdns(struct pci_dev *pdev)
+{
+	struct pci_dn *parent, *pdn;
+	int i;
+
+	/* Only support IOV for now */
+	if (WARN_ON(!pdev->is_physfn))
+		return NULL;
+
+	/* Check if VFs have been populated */
+	pdn = pci_get_pdn(pdev);
+	if (!pdn || (pdn->flags & PCI_DN_FLAG_IOV_VF))
+		return NULL;
+
+	pdn->flags |= PCI_DN_FLAG_IOV_VF;
+	parent = pci_bus_to_pdn(pdev->bus);
+	if (!parent)
+		return NULL;
+
+	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
+		struct eeh_dev *edev __maybe_unused;
+
+		pdn = add_one_sriov_vf_pdn(parent,
+					   pci_iov_virtfn_bus(pdev, i),
+					   pci_iov_virtfn_devfn(pdev, i));
+		if (!pdn) {
+			dev_warn(&pdev->dev, "%s: Cannot create firmware data for VF#%d\n",
+				 __func__, i);
+			return NULL;
+		}
+
+#ifdef CONFIG_EEH
+		/* Create the EEH device for the VF */
+		edev = eeh_dev_init(pdn);
+		BUG_ON(!edev);
+
+		/* FIXME: these should probably be populated by the EEH probe */
+		edev->physfn = pdev;
+		edev->vf_index = i;
+#endif /* CONFIG_EEH */
+	}
+	return pci_get_pdn(pdev);
+}
+
+void remove_sriov_vf_pdns(struct pci_dev *pdev)
+{
+	struct pci_dn *parent;
+	struct pci_dn *pdn, *tmp;
+	int i;
+
+	/* Only support IOV PF for now */
+	if (WARN_ON(!pdev->is_physfn))
+		return;
+
+	/* Check if VFs have been populated */
+	pdn = pci_get_pdn(pdev);
+	if (!pdn || !(pdn->flags & PCI_DN_FLAG_IOV_VF))
+		return;
+
+	pdn->flags &= ~PCI_DN_FLAG_IOV_VF;
+	parent = pci_bus_to_pdn(pdev->bus);
+	if (!parent)
+		return;
+
+	/*
+	 * We might introduce flag to pci_dn in future
+	 * so that we can release VF's firmware data in
+	 * a batch mode.
+	 */
+	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
+		struct eeh_dev *edev __maybe_unused;
+
+		list_for_each_entry_safe(pdn, tmp,
+			&parent->child_list, list) {
+			if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
+			    pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
+				continue;
+
+#ifdef CONFIG_EEH
+			/*
+			 * Release EEH state for this VF. The PCI core
+			 * has already torn down the pci_dev for this VF, but
+			 * we're responsible to removing the eeh_dev since it
+			 * has the same lifetime as the pci_dn that spawned it.
+			 */
+			edev = pdn_to_eeh_dev(pdn);
+			if (edev) {
+				/*
+				 * We allocate pci_dn's for the totalvfs count,
+				 * but only the vfs that were activated
+				 * have a configured PE.
+				 */
+				if (edev->pe)
+					eeh_pe_tree_remove(edev);
+
+				pdn->edev = NULL;
+				kfree(edev);
+			}
+#endif /* CONFIG_EEH */
+
+			if (!list_empty(&pdn->list))
+				list_del(&pdn->list);
+
+			kfree(pdn);
+		}
+	}
+}
+#endif /* CONFIG_PCI_IOV */
+
+struct pci_dn *pci_add_device_node_info(struct pci_controller *hose,
+					struct device_node *dn)
+{
+	const __be32 *type = of_get_property(dn, "ibm,pci-config-space-type", NULL);
+	const __be32 *regs;
+	struct device_node *parent;
+	struct pci_dn *pdn;
+#ifdef CONFIG_EEH
+	struct eeh_dev *edev;
+#endif
+
+	pdn = kzalloc(sizeof(*pdn), GFP_KERNEL);
+	if (pdn == NULL)
+		return NULL;
+	dn->data = pdn;
+	pdn->phb = hose;
+	pdn->pe_number = IODA_INVALID_PE;
+	regs = of_get_property(dn, "reg", NULL);
+	if (regs) {
+		u32 addr = of_read_number(regs, 1);
+
+		/* First register entry is addr (00BBSS00)  */
+		pdn->busno = (addr >> 16) & 0xff;
+		pdn->devfn = (addr >> 8) & 0xff;
+	}
+
+	/* vendor/device IDs and class code */
+	regs = of_get_property(dn, "vendor-id", NULL);
+	pdn->vendor_id = regs ? of_read_number(regs, 1) : 0;
+	regs = of_get_property(dn, "device-id", NULL);
+	pdn->device_id = regs ? of_read_number(regs, 1) : 0;
+	regs = of_get_property(dn, "class-code", NULL);
+	pdn->class_code = regs ? of_read_number(regs, 1) : 0;
+
+	/* Extended config space */
+	pdn->pci_ext_config_space = (type && of_read_number(type, 1) == 1);
+
+	/* Create EEH device */
+#ifdef CONFIG_EEH
+	edev = eeh_dev_init(pdn);
+	if (!edev) {
+		kfree(pdn);
+		return NULL;
+	}
+#endif
+
+	/* 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;
+	of_node_put(parent);
+	if (pdn->parent)
+		list_add_tail(&pdn->list, &pdn->parent->child_list);
+
+	return pdn;
+}
+EXPORT_SYMBOL_GPL(pci_add_device_node_info);
+
+void pci_remove_device_node_info(struct device_node *dn)
+{
+	struct pci_dn *pdn = dn ? PCI_DN(dn) : NULL;
+	struct device_node *parent;
+	struct pci_dev *pdev;
+#ifdef CONFIG_EEH
+	struct eeh_dev *edev = pdn_to_eeh_dev(pdn);
+
+	if (edev)
+		edev->pdn = NULL;
+#endif
+
+	if (!pdn)
+		return;
+
+	WARN_ON(!list_empty(&pdn->child_list));
+	list_del(&pdn->list);
+
+	/* Drop the parent pci_dn's ref to our backing dt node */
+	parent = of_get_parent(dn);
+	if (parent)
+		of_node_put(parent);
+
+	/*
+	 * At this point we *might* still have a pci_dev that was
+	 * instantiated from this pci_dn. So defer free()ing it until
+	 * the pci_dev's release function is called.
+	 */
+	pdev = pci_get_domain_bus_and_slot(pdn->phb->global_number,
+			pdn->busno, pdn->devfn);
+	if (pdev) {
+		/* NB: pdev has a ref to dn */
+		pci_dbg(pdev, "marked pdn (from %pOF) as dead\n", dn);
+		pdn->flags |= PCI_DN_FLAG_DEAD;
+	} else {
+		dn->data = NULL;
+		kfree(pdn);
+	}
+
+	pci_dev_put(pdev);
+}
+EXPORT_SYMBOL_GPL(pci_remove_device_node_info);
+
+/*
+ * Traverse a device tree stopping each PCI device in the tree.
+ * This is done depth first.  As each node is processed, a "pre"
+ * function is called and the children are processed recursively.
+ *
+ * The "pre" func returns a value.  If non-zero is returned from
+ * the "pre" func, the traversal stops and this value is returned.
+ * This return value is useful when using traverse as a method of
+ * finding a device.
+ *
+ * NOTE: we do not run the func for devices that do not appear to
+ * be PCI except for the start node which we assume (this is good
+ * because the start node is often a phb which may be missing PCI
+ * properties).
+ * We use the class-code as an indicator. If we run into
+ * one of these nodes we also assume its siblings are non-pci for
+ * performance.
+ */
+void *pci_traverse_device_nodes(struct device_node *start,
+				void *(*fn)(struct device_node *, void *),
+				void *data)
+{
+	struct device_node *dn, *nextdn;
+	void *ret;
+
+	/* We started with a phb, iterate all childs */
+	for (dn = start->child; dn; dn = nextdn) {
+		const __be32 *classp;
+		u32 class = 0;
+
+		nextdn = NULL;
+		classp = of_get_property(dn, "class-code", NULL);
+		if (classp)
+			class = of_read_number(classp, 1);
+
+		if (fn) {
+			ret = fn(dn, data);
+			if (ret)
+				return ret;
+		}
+
+		/* If we are a PCI bridge, go down */
+		if (dn->child && ((class >> 8) == PCI_CLASS_BRIDGE_PCI ||
+				  (class >> 8) == PCI_CLASS_BRIDGE_CARDBUS))
+			/* Depth first...do children */
+			nextdn = dn->child;
+		else if (dn->sibling)
+			/* ok, try next sibling instead. */
+			nextdn = dn->sibling;
+		if (!nextdn) {
+			/* Walk up to next valid sibling. */
+			do {
+				dn = dn->parent;
+				if (dn == start)
+					return NULL;
+			} while (dn->sibling == NULL);
+			nextdn = dn->sibling;
+		}
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(pci_traverse_device_nodes);
+
+static void *add_pdn(struct device_node *dn, void *data)
+{
+	struct pci_controller *hose = data;
+	struct pci_dn *pdn;
+
+	pdn = pci_add_device_node_info(hose, dn);
+	if (!pdn)
+		return ERR_PTR(-ENOMEM);
+
+	return NULL;
+}
+
+/** 
+ * pci_devs_phb_init_dynamic - setup pci devices under this PHB
+ * phb: pci-to-host bridge (top-level bridge connecting to cpu)
+ *
+ * This routine is called both during boot, (before the memory
+ * subsystem is set up, before kmalloc is valid) and during the 
+ * dynamic lpar operation of adding a PHB to a running system.
+ */
+void pci_devs_phb_init_dynamic(struct pci_controller *phb)
+{
+	struct device_node *dn = phb->dn;
+	struct pci_dn *pdn;
+
+	/* PHB nodes themselves must not match */
+	pdn = pci_add_device_node_info(phb, dn);
+	if (pdn) {
+		pdn->devfn = pdn->busno = -1;
+		pdn->vendor_id = pdn->device_id = pdn->class_code = 0;
+		pdn->phb = phb;
+		phb->pci_data = pdn;
+	}
+
+	/* Update dn->phb ptrs for new phb and children devices */
+	pci_traverse_device_nodes(dn, add_pdn, 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);