Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 409 insertions, 0 deletions

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
new file mode 100644
index 0000000000..f2f4a5d50b
--- /dev/null
+++ b/arch/x86/pci/i386.c
@@ -0,0 +1,409 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *	Low-Level PCI Access for i386 machines
+ *
+ * Copyright 1993, 1994 Drew Eckhardt
+ *      Visionary Computing
+ *      (Unix and Linux consulting and custom programming)
+ *      Drew@Colorado.EDU
+ *      +1 (303) 786-7975
+ *
+ * Drew's work was sponsored by:
+ *	iX Multiuser Multitasking Magazine
+ *	Hannover, Germany
+ *	hm@ix.de
+ *
+ * Copyright 1997--2000 Martin Mares <mj@ucw.cz>
+ *
+ * For more information, please consult the following manuals (look at
+ * http://www.pcisig.com/ for how to get them):
+ *
+ * PCI BIOS Specification
+ * PCI Local Bus Specification
+ * PCI to PCI Bridge Specification
+ * PCI System Design Guide
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/pci.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/errno.h>
+#include <linux/memblock.h>
+
+#include <asm/memtype.h>
+#include <asm/e820/api.h>
+#include <asm/pci_x86.h>
+#include <asm/io_apic.h>
+
+
+/*
+ * This list of dynamic mappings is for temporarily maintaining
+ * original BIOS BAR addresses for possible reinstatement.
+ */
+struct pcibios_fwaddrmap {
+	struct list_head list;
+	struct pci_dev *dev;
+	resource_size_t fw_addr[DEVICE_COUNT_RESOURCE];
+};
+
+static LIST_HEAD(pcibios_fwaddrmappings);
+static DEFINE_SPINLOCK(pcibios_fwaddrmap_lock);
+static bool pcibios_fw_addr_done;
+
+/* Must be called with 'pcibios_fwaddrmap_lock' lock held. */
+static struct pcibios_fwaddrmap *pcibios_fwaddrmap_lookup(struct pci_dev *dev)
+{
+	struct pcibios_fwaddrmap *map;
+
+	lockdep_assert_held(&pcibios_fwaddrmap_lock);
+
+	list_for_each_entry(map, &pcibios_fwaddrmappings, list)
+		if (map->dev == dev)
+			return map;
+
+	return NULL;
+}
+
+static void
+pcibios_save_fw_addr(struct pci_dev *dev, int idx, resource_size_t fw_addr)
+{
+	unsigned long flags;
+	struct pcibios_fwaddrmap *map;
+
+	if (pcibios_fw_addr_done)
+		return;
+
+	spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
+	map = pcibios_fwaddrmap_lookup(dev);
+	if (!map) {
+		spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
+		map = kzalloc(sizeof(*map), GFP_KERNEL);
+		if (!map)
+			return;
+
+		map->dev = pci_dev_get(dev);
+		map->fw_addr[idx] = fw_addr;
+		INIT_LIST_HEAD(&map->list);
+
+		spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
+		list_add_tail(&map->list, &pcibios_fwaddrmappings);
+	} else
+		map->fw_addr[idx] = fw_addr;
+	spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
+}
+
+resource_size_t pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
+{
+	unsigned long flags;
+	struct pcibios_fwaddrmap *map;
+	resource_size_t fw_addr = 0;
+
+	if (pcibios_fw_addr_done)
+		return 0;
+
+	spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
+	map = pcibios_fwaddrmap_lookup(dev);
+	if (map)
+		fw_addr = map->fw_addr[idx];
+	spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
+
+	return fw_addr;
+}
+
+static void __init pcibios_fw_addr_list_del(void)
+{
+	unsigned long flags;
+	struct pcibios_fwaddrmap *entry, *next;
+
+	spin_lock_irqsave(&pcibios_fwaddrmap_lock, flags);
+	list_for_each_entry_safe(entry, next, &pcibios_fwaddrmappings, list) {
+		list_del(&entry->list);
+		pci_dev_put(entry->dev);
+		kfree(entry);
+	}
+	spin_unlock_irqrestore(&pcibios_fwaddrmap_lock, flags);
+	pcibios_fw_addr_done = true;
+}
+
+static int
+skip_isa_ioresource_align(struct pci_dev *dev) {
+
+	if ((pci_probe & PCI_CAN_SKIP_ISA_ALIGN) &&
+	    !(dev->bus->bridge_ctl & PCI_BRIDGE_CTL_ISA))
+		return 1;
+	return 0;
+}
+
+/*
+ * We need to avoid collisions with `mirrored' VGA ports
+ * and other strange ISA hardware, so we always want the
+ * addresses to be allocated in the 0x000-0x0ff region
+ * modulo 0x400.
+ *
+ * Why? Because some silly external IO cards only decode
+ * the low 10 bits of the IO address. The 0x00-0xff region
+ * is reserved for motherboard devices that decode all 16
+ * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
+ * but we want to try to avoid allocating at 0x2900-0x2bff
+ * which might have be mirrored at 0x0100-0x03ff..
+ */
+resource_size_t
+pcibios_align_resource(void *data, const struct resource *res,
+			resource_size_t size, resource_size_t align)
+{
+	struct pci_dev *dev = data;
+	resource_size_t start = res->start;
+
+	if (res->flags & IORESOURCE_IO) {
+		if (skip_isa_ioresource_align(dev))
+			return start;
+		if (start & 0x300)
+			start = (start + 0x3ff) & ~0x3ff;
+	} else if (res->flags & IORESOURCE_MEM) {
+		/* The low 1MB range is reserved for ISA cards */
+		if (start < BIOS_END)
+			start = BIOS_END;
+	}
+	return start;
+}
+EXPORT_SYMBOL(pcibios_align_resource);
+
+/*
+ *  Handle resources of PCI devices.  If the world were perfect, we could
+ *  just allocate all the resource regions and do nothing more.  It isn't.
+ *  On the other hand, we cannot just re-allocate all devices, as it would
+ *  require us to know lots of host bridge internals.  So we attempt to
+ *  keep as much of the original configuration as possible, but tweak it
+ *  when it's found to be wrong.
+ *
+ *  Known BIOS problems we have to work around:
+ *	- I/O or memory regions not configured
+ *	- regions configured, but not enabled in the command register
+ *	- bogus I/O addresses above 64K used
+ *	- expansion ROMs left enabled (this may sound harmless, but given
+ *	  the fact the PCI specs explicitly allow address decoders to be
+ *	  shared between expansion ROMs and other resource regions, it's
+ *	  at least dangerous)
+ *	- bad resource sizes or overlaps with other regions
+ *
+ *  Our solution:
+ *	(1) Allocate resources for all buses behind PCI-to-PCI bridges.
+ *	    This gives us fixed barriers on where we can allocate.
+ *	(2) Allocate resources for all enabled devices.  If there is
+ *	    a collision, just mark the resource as unallocated. Also
+ *	    disable expansion ROMs during this step.
+ *	(3) Try to allocate resources for disabled devices.  If the
+ *	    resources were assigned correctly, everything goes well,
+ *	    if they weren't, they won't disturb allocation of other
+ *	    resources.
+ *	(4) Assign new addresses to resources which were either
+ *	    not configured at all or misconfigured.  If explicitly
+ *	    requested by the user, configure expansion ROM address
+ *	    as well.
+ */
+
+static void pcibios_allocate_bridge_resources(struct pci_dev *dev)
+{
+	int idx;
+	struct resource *r;
+
+	for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_NUM_RESOURCES; idx++) {
+		r = &dev->resource[idx];
+		if (!r->flags)
+			continue;
+		if (r->parent)	/* Already allocated */
+			continue;
+		if (!r->start || pci_claim_bridge_resource(dev, idx) < 0) {
+			/*
+			 * Something is wrong with the region.
+			 * Invalidate the resource to prevent
+			 * child resource allocations in this
+			 * range.
+			 */
+			r->start = r->end = 0;
+			r->flags = 0;
+		}
+	}
+}
+
+static void pcibios_allocate_bus_resources(struct pci_bus *bus)
+{
+	struct pci_bus *child;
+
+	/* Depth-First Search on bus tree */
+	if (bus->self)
+		pcibios_allocate_bridge_resources(bus->self);
+	list_for_each_entry(child, &bus->children, node)
+		pcibios_allocate_bus_resources(child);
+}
+
+struct pci_check_idx_range {
+	int start;
+	int end;
+};
+
+static void pcibios_allocate_dev_resources(struct pci_dev *dev, int pass)
+{
+	int idx, disabled, i;
+	u16 command;
+	struct resource *r;
+
+	struct pci_check_idx_range idx_range[] = {
+		{ PCI_STD_RESOURCES, PCI_STD_RESOURCE_END },
+#ifdef CONFIG_PCI_IOV
+		{ PCI_IOV_RESOURCES, PCI_IOV_RESOURCE_END },
+#endif
+	};
+
+	pci_read_config_word(dev, PCI_COMMAND, &command);
+	for (i = 0; i < ARRAY_SIZE(idx_range); i++)
+		for (idx = idx_range[i].start; idx <= idx_range[i].end; idx++) {
+			r = &dev->resource[idx];
+			if (r->parent)	/* Already allocated */
+				continue;
+			if (!r->start)	/* Address not assigned at all */
+				continue;
+			if (r->flags & IORESOURCE_IO)
+				disabled = !(command & PCI_COMMAND_IO);
+			else
+				disabled = !(command & PCI_COMMAND_MEMORY);
+			if (pass == disabled) {
+				dev_dbg(&dev->dev,
+					"BAR %d: reserving %pr (d=%d, p=%d)\n",
+					idx, r, disabled, pass);
+				if (pci_claim_resource(dev, idx) < 0) {
+					if (r->flags & IORESOURCE_PCI_FIXED) {
+						dev_info(&dev->dev, "BAR %d %pR is immovable\n",
+							 idx, r);
+					} else {
+						/* We'll assign a new address later */
+						pcibios_save_fw_addr(dev,
+								idx, r->start);
+						r->end -= r->start;
+						r->start = 0;
+					}
+				}
+			}
+		}
+	if (!pass) {
+		r = &dev->resource[PCI_ROM_RESOURCE];
+		if (r->flags & IORESOURCE_ROM_ENABLE) {
+			/* Turn the ROM off, leave the resource region,
+			 * but keep it unregistered. */
+			u32 reg;
+			dev_dbg(&dev->dev, "disabling ROM %pR\n", r);
+			r->flags &= ~IORESOURCE_ROM_ENABLE;
+			pci_read_config_dword(dev, dev->rom_base_reg, &reg);
+			pci_write_config_dword(dev, dev->rom_base_reg,
+						reg & ~PCI_ROM_ADDRESS_ENABLE);
+		}
+	}
+}
+
+static void pcibios_allocate_resources(struct pci_bus *bus, int pass)
+{
+	struct pci_dev *dev;
+	struct pci_bus *child;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		pcibios_allocate_dev_resources(dev, pass);
+
+		child = dev->subordinate;
+		if (child)
+			pcibios_allocate_resources(child, pass);
+	}
+}
+
+static void pcibios_allocate_dev_rom_resource(struct pci_dev *dev)
+{
+	struct resource *r;
+
+	/*
+	 * Try to use BIOS settings for ROMs, otherwise let
+	 * pci_assign_unassigned_resources() allocate the new
+	 * addresses.
+	 */
+	r = &dev->resource[PCI_ROM_RESOURCE];
+	if (!r->flags || !r->start)
+		return;
+	if (r->parent) /* Already allocated */
+		return;
+
+	if (pci_claim_resource(dev, PCI_ROM_RESOURCE) < 0) {
+		r->end -= r->start;
+		r->start = 0;
+	}
+}
+static void pcibios_allocate_rom_resources(struct pci_bus *bus)
+{
+	struct pci_dev *dev;
+	struct pci_bus *child;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		pcibios_allocate_dev_rom_resource(dev);
+
+		child = dev->subordinate;
+		if (child)
+			pcibios_allocate_rom_resources(child);
+	}
+}
+
+static int __init pcibios_assign_resources(void)
+{
+	struct pci_bus *bus;
+
+	if (!(pci_probe & PCI_ASSIGN_ROMS))
+		list_for_each_entry(bus, &pci_root_buses, node)
+			pcibios_allocate_rom_resources(bus);
+
+	pci_assign_unassigned_resources();
+	pcibios_fw_addr_list_del();
+
+	return 0;
+}
+
+/*
+ * This is an fs_initcall (one below subsys_initcall) in order to reserve
+ * resources properly.
+ */
+fs_initcall(pcibios_assign_resources);
+
+void pcibios_resource_survey_bus(struct pci_bus *bus)
+{
+	dev_printk(KERN_DEBUG, &bus->dev, "Allocating resources\n");
+
+	pcibios_allocate_bus_resources(bus);
+
+	pcibios_allocate_resources(bus, 0);
+	pcibios_allocate_resources(bus, 1);
+
+	if (!(pci_probe & PCI_ASSIGN_ROMS))
+		pcibios_allocate_rom_resources(bus);
+}
+
+void __init pcibios_resource_survey(void)
+{
+	struct pci_bus *bus;
+
+	DBG("PCI: Allocating resources\n");
+
+	list_for_each_entry(bus, &pci_root_buses, node)
+		pcibios_allocate_bus_resources(bus);
+
+	list_for_each_entry(bus, &pci_root_buses, node)
+		pcibios_allocate_resources(bus, 0);
+	list_for_each_entry(bus, &pci_root_buses, node)
+		pcibios_allocate_resources(bus, 1);
+
+	e820__reserve_resources_late();
+	/*
+	 * Insert the IO APIC resources after PCI initialization has
+	 * occurred to handle IO APICS that are mapped in on a BAR in
+	 * PCI space, but before trying to assign unassigned pci res.
+	 */
+	ioapic_insert_resources();
+}