1 files changed, 522 insertions, 0 deletions

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
new file mode 100644
index 000000000..b492e67c3
--- /dev/null
+++ b/drivers/pci/setup-res.c
@@ -0,0 +1,522 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support routines for initializing a PCI subsystem
+ *
+ * Extruded from code written by
+ *      Dave Rusling (david.rusling@reo.mts.dec.com)
+ *      David Mosberger (davidm@cs.arizona.edu)
+ *	David Miller (davem@redhat.com)
+ *
+ * Fixed for multiple PCI buses, 1999 Andrea Arcangeli <andrea@suse.de>
+ *
+ * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
+ *	     Resource sorting
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/pci.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+#include <linux/cache.h>
+#include <linux/slab.h>
+#include "pci.h"
+
+static void pci_std_update_resource(struct pci_dev *dev, int resno)
+{
+	struct pci_bus_region region;
+	bool disable;
+	u16 cmd;
+	u32 new, check, mask;
+	int reg;
+	struct resource *res = dev->resource + resno;
+
+	/* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */
+	if (dev->is_virtfn)
+		return;
+
+	/*
+	 * Ignore resources for unimplemented BARs and unused resource slots
+	 * for 64 bit BARs.
+	 */
+	if (!res->flags)
+		return;
+
+	if (res->flags & IORESOURCE_UNSET)
+		return;
+
+	/*
+	 * Ignore non-moveable resources.  This might be legacy resources for
+	 * which no functional BAR register exists or another important
+	 * system resource we shouldn't move around.
+	 */
+	if (res->flags & IORESOURCE_PCI_FIXED)
+		return;
+
+	pcibios_resource_to_bus(dev->bus, &region, res);
+	new = region.start;
+
+	if (res->flags & IORESOURCE_IO) {
+		mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
+		new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
+	} else if (resno == PCI_ROM_RESOURCE) {
+		mask = PCI_ROM_ADDRESS_MASK;
+	} else {
+		mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
+		new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;
+	}
+
+	if (resno < PCI_ROM_RESOURCE) {
+		reg = PCI_BASE_ADDRESS_0 + 4 * resno;
+	} else if (resno == PCI_ROM_RESOURCE) {
+
+		/*
+		 * Apparently some Matrox devices have ROM BARs that read
+		 * as zero when disabled, so don't update ROM BARs unless
+		 * they're enabled.  See
+		 * https://lore.kernel.org/r/43147B3D.1030309@vc.cvut.cz/
+		 * But we must update ROM BAR for buggy devices where even a
+		 * disabled ROM can conflict with other BARs.
+		 */
+		if (!(res->flags & IORESOURCE_ROM_ENABLE) &&
+		    !dev->rom_bar_overlap)
+			return;
+
+		reg = dev->rom_base_reg;
+		if (res->flags & IORESOURCE_ROM_ENABLE)
+			new |= PCI_ROM_ADDRESS_ENABLE;
+	} else
+		return;
+
+	/*
+	 * We can't update a 64-bit BAR atomically, so when possible,
+	 * disable decoding so that a half-updated BAR won't conflict
+	 * with another device.
+	 */
+	disable = (res->flags & IORESOURCE_MEM_64) && !dev->mmio_always_on;
+	if (disable) {
+		pci_read_config_word(dev, PCI_COMMAND, &cmd);
+		pci_write_config_word(dev, PCI_COMMAND,
+				      cmd & ~PCI_COMMAND_MEMORY);
+	}
+
+	pci_write_config_dword(dev, reg, new);
+	pci_read_config_dword(dev, reg, &check);
+
+	if ((new ^ check) & mask) {
+		pci_err(dev, "BAR %d: error updating (%#08x != %#08x)\n",
+			resno, new, check);
+	}
+
+	if (res->flags & IORESOURCE_MEM_64) {
+		new = region.start >> 16 >> 16;
+		pci_write_config_dword(dev, reg + 4, new);
+		pci_read_config_dword(dev, reg + 4, &check);
+		if (check != new) {
+			pci_err(dev, "BAR %d: error updating (high %#08x != %#08x)\n",
+				resno, new, check);
+		}
+	}
+
+	if (disable)
+		pci_write_config_word(dev, PCI_COMMAND, cmd);
+}
+
+void pci_update_resource(struct pci_dev *dev, int resno)
+{
+	if (resno <= PCI_ROM_RESOURCE)
+		pci_std_update_resource(dev, resno);
+#ifdef CONFIG_PCI_IOV
+	else if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
+		pci_iov_update_resource(dev, resno);
+#endif
+}
+
+int pci_claim_resource(struct pci_dev *dev, int resource)
+{
+	struct resource *res = &dev->resource[resource];
+	struct resource *root, *conflict;
+
+	if (res->flags & IORESOURCE_UNSET) {
+		pci_info(dev, "can't claim BAR %d %pR: no address assigned\n",
+			 resource, res);
+		return -EINVAL;
+	}
+
+	/*
+	 * If we have a shadow copy in RAM, the PCI device doesn't respond
+	 * to the shadow range, so we don't need to claim it, and upstream
+	 * bridges don't need to route the range to the device.
+	 */
+	if (res->flags & IORESOURCE_ROM_SHADOW)
+		return 0;
+
+	root = pci_find_parent_resource(dev, res);
+	if (!root) {
+		pci_info(dev, "can't claim BAR %d %pR: no compatible bridge window\n",
+			 resource, res);
+		res->flags |= IORESOURCE_UNSET;
+		return -EINVAL;
+	}
+
+	conflict = request_resource_conflict(root, res);
+	if (conflict) {
+		pci_info(dev, "can't claim BAR %d %pR: address conflict with %s %pR\n",
+			 resource, res, conflict->name, conflict);
+		res->flags |= IORESOURCE_UNSET;
+		return -EBUSY;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(pci_claim_resource);
+
+void pci_disable_bridge_window(struct pci_dev *dev)
+{
+	/* MMIO Base/Limit */
+	pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0);
+
+	/* Prefetchable MMIO Base/Limit */
+	pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0);
+	pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0);
+	pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff);
+}
+
+/*
+ * Generic function that returns a value indicating that the device's
+ * original BIOS BAR address was not saved and so is not available for
+ * reinstatement.
+ *
+ * Can be over-ridden by architecture specific code that implements
+ * reinstatement functionality rather than leaving it disabled when
+ * normal allocation attempts fail.
+ */
+resource_size_t __weak pcibios_retrieve_fw_addr(struct pci_dev *dev, int idx)
+{
+	return 0;
+}
+
+static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev,
+		int resno, resource_size_t size)
+{
+	struct resource *root, *conflict;
+	resource_size_t fw_addr, start, end;
+
+	fw_addr = pcibios_retrieve_fw_addr(dev, resno);
+	if (!fw_addr)
+		return -ENOMEM;
+
+	start = res->start;
+	end = res->end;
+	res->start = fw_addr;
+	res->end = res->start + size - 1;
+	res->flags &= ~IORESOURCE_UNSET;
+
+	root = pci_find_parent_resource(dev, res);
+	if (!root) {
+		/*
+		 * If dev is behind a bridge, accesses will only reach it
+		 * if res is inside the relevant bridge window.
+		 */
+		if (pci_upstream_bridge(dev))
+			return -ENXIO;
+
+		/*
+		 * On the root bus, assume the host bridge will forward
+		 * everything.
+		 */
+		if (res->flags & IORESOURCE_IO)
+			root = &ioport_resource;
+		else
+			root = &iomem_resource;
+	}
+
+	pci_info(dev, "BAR %d: trying firmware assignment %pR\n",
+		 resno, res);
+	conflict = request_resource_conflict(root, res);
+	if (conflict) {
+		pci_info(dev, "BAR %d: %pR conflicts with %s %pR\n",
+			 resno, res, conflict->name, conflict);
+		res->start = start;
+		res->end = end;
+		res->flags |= IORESOURCE_UNSET;
+		return -EBUSY;
+	}
+	return 0;
+}
+
+/*
+ * We don't have to worry about legacy ISA devices, so nothing to do here.
+ * This is marked as __weak because multiple architectures define it; it should
+ * eventually go away.
+ */
+resource_size_t __weak pcibios_align_resource(void *data,
+					      const struct resource *res,
+					      resource_size_t size,
+					      resource_size_t align)
+{
+       return res->start;
+}
+
+static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev,
+		int resno, resource_size_t size, resource_size_t align)
+{
+	struct resource *res = dev->resource + resno;
+	resource_size_t min;
+	int ret;
+
+	min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
+
+	/*
+	 * First, try exact prefetching match.  Even if a 64-bit
+	 * prefetchable bridge window is below 4GB, we can't put a 32-bit
+	 * prefetchable resource in it because pbus_size_mem() assumes a
+	 * 64-bit window will contain no 32-bit resources.  If we assign
+	 * things differently than they were sized, not everything will fit.
+	 */
+	ret = pci_bus_alloc_resource(bus, res, size, align, min,
+				     IORESOURCE_PREFETCH | IORESOURCE_MEM_64,
+				     pcibios_align_resource, dev);
+	if (ret == 0)
+		return 0;
+
+	/*
+	 * If the prefetchable window is only 32 bits wide, we can put
+	 * 64-bit prefetchable resources in it.
+	 */
+	if ((res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) ==
+	     (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) {
+		ret = pci_bus_alloc_resource(bus, res, size, align, min,
+					     IORESOURCE_PREFETCH,
+					     pcibios_align_resource, dev);
+		if (ret == 0)
+			return 0;
+	}
+
+	/*
+	 * If we didn't find a better match, we can put any memory resource
+	 * in a non-prefetchable window.  If this resource is 32 bits and
+	 * non-prefetchable, the first call already tried the only possibility
+	 * so we don't need to try again.
+	 */
+	if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64))
+		ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
+					     pcibios_align_resource, dev);
+
+	return ret;
+}
+
+static int _pci_assign_resource(struct pci_dev *dev, int resno,
+				resource_size_t size, resource_size_t min_align)
+{
+	struct pci_bus *bus;
+	int ret;
+
+	bus = dev->bus;
+	while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) {
+		if (!bus->parent || !bus->self->transparent)
+			break;
+		bus = bus->parent;
+	}
+
+	return ret;
+}
+
+int pci_assign_resource(struct pci_dev *dev, int resno)
+{
+	struct resource *res = dev->resource + resno;
+	resource_size_t align, size;
+	int ret;
+
+	if (res->flags & IORESOURCE_PCI_FIXED)
+		return 0;
+
+	res->flags |= IORESOURCE_UNSET;
+	align = pci_resource_alignment(dev, res);
+	if (!align) {
+		pci_info(dev, "BAR %d: can't assign %pR (bogus alignment)\n",
+			 resno, res);
+		return -EINVAL;
+	}
+
+	size = resource_size(res);
+	ret = _pci_assign_resource(dev, resno, size, align);
+
+	/*
+	 * If we failed to assign anything, let's try the address
+	 * where firmware left it.  That at least has a chance of
+	 * working, which is better than just leaving it disabled.
+	 */
+	if (ret < 0) {
+		pci_info(dev, "BAR %d: no space for %pR\n", resno, res);
+		ret = pci_revert_fw_address(res, dev, resno, size);
+	}
+
+	if (ret < 0) {
+		pci_info(dev, "BAR %d: failed to assign %pR\n", resno, res);
+		return ret;
+	}
+
+	res->flags &= ~IORESOURCE_UNSET;
+	res->flags &= ~IORESOURCE_STARTALIGN;
+	pci_info(dev, "BAR %d: assigned %pR\n", resno, res);
+	if (resno < PCI_BRIDGE_RESOURCES)
+		pci_update_resource(dev, resno);
+
+	return 0;
+}
+EXPORT_SYMBOL(pci_assign_resource);
+
+int pci_reassign_resource(struct pci_dev *dev, int resno, resource_size_t addsize,
+			resource_size_t min_align)
+{
+	struct resource *res = dev->resource + resno;
+	unsigned long flags;
+	resource_size_t new_size;
+	int ret;
+
+	if (res->flags & IORESOURCE_PCI_FIXED)
+		return 0;
+
+	flags = res->flags;
+	res->flags |= IORESOURCE_UNSET;
+	if (!res->parent) {
+		pci_info(dev, "BAR %d: can't reassign an unassigned resource %pR\n",
+			 resno, res);
+		return -EINVAL;
+	}
+
+	/* already aligned with min_align */
+	new_size = resource_size(res) + addsize;
+	ret = _pci_assign_resource(dev, resno, new_size, min_align);
+	if (ret) {
+		res->flags = flags;
+		pci_info(dev, "BAR %d: %pR (failed to expand by %#llx)\n",
+			 resno, res, (unsigned long long) addsize);
+		return ret;
+	}
+
+	res->flags &= ~IORESOURCE_UNSET;
+	res->flags &= ~IORESOURCE_STARTALIGN;
+	pci_info(dev, "BAR %d: reassigned %pR (expanded by %#llx)\n",
+		 resno, res, (unsigned long long) addsize);
+	if (resno < PCI_BRIDGE_RESOURCES)
+		pci_update_resource(dev, resno);
+
+	return 0;
+}
+
+void pci_release_resource(struct pci_dev *dev, int resno)
+{
+	struct resource *res = dev->resource + resno;
+
+	pci_info(dev, "BAR %d: releasing %pR\n", resno, res);
+
+	if (!res->parent)
+		return;
+
+	release_resource(res);
+	res->end = resource_size(res) - 1;
+	res->start = 0;
+	res->flags |= IORESOURCE_UNSET;
+}
+EXPORT_SYMBOL(pci_release_resource);
+
+int pci_resize_resource(struct pci_dev *dev, int resno, int size)
+{
+	struct resource *res = dev->resource + resno;
+	struct pci_host_bridge *host;
+	int old, ret;
+	u32 sizes;
+	u16 cmd;
+
+	/* Check if we must preserve the firmware's resource assignment */
+	host = pci_find_host_bridge(dev->bus);
+	if (host->preserve_config)
+		return -ENOTSUPP;
+
+	/* Make sure the resource isn't assigned before resizing it. */
+	if (!(res->flags & IORESOURCE_UNSET))
+		return -EBUSY;
+
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	if (cmd & PCI_COMMAND_MEMORY)
+		return -EBUSY;
+
+	sizes = pci_rebar_get_possible_sizes(dev, resno);
+	if (!sizes)
+		return -ENOTSUPP;
+
+	if (!(sizes & BIT(size)))
+		return -EINVAL;
+
+	old = pci_rebar_get_current_size(dev, resno);
+	if (old < 0)
+		return old;
+
+	ret = pci_rebar_set_size(dev, resno, size);
+	if (ret)
+		return ret;
+
+	res->end = res->start + pci_rebar_size_to_bytes(size) - 1;
+
+	/* Check if the new config works by trying to assign everything. */
+	if (dev->bus->self) {
+		ret = pci_reassign_bridge_resources(dev->bus->self, res->flags);
+		if (ret)
+			goto error_resize;
+	}
+	return 0;
+
+error_resize:
+	pci_rebar_set_size(dev, resno, old);
+	res->end = res->start + pci_rebar_size_to_bytes(old) - 1;
+	return ret;
+}
+EXPORT_SYMBOL(pci_resize_resource);
+
+int pci_enable_resources(struct pci_dev *dev, int mask)
+{
+	u16 cmd, old_cmd;
+	int i;
+	struct resource *r;
+
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	old_cmd = cmd;
+
+	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+		if (!(mask & (1 << i)))
+			continue;
+
+		r = &dev->resource[i];
+
+		if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
+			continue;
+		if ((i == PCI_ROM_RESOURCE) &&
+				(!(r->flags & IORESOURCE_ROM_ENABLE)))
+			continue;
+
+		if (r->flags & IORESOURCE_UNSET) {
+			pci_err(dev, "can't enable device: BAR %d %pR not assigned\n",
+				i, r);
+			return -EINVAL;
+		}
+
+		if (!r->parent) {
+			pci_err(dev, "can't enable device: BAR %d %pR not claimed\n",
+				i, r);
+			return -EINVAL;
+		}
+
+		if (r->flags & IORESOURCE_IO)
+			cmd |= PCI_COMMAND_IO;
+		if (r->flags & IORESOURCE_MEM)
+			cmd |= PCI_COMMAND_MEMORY;
+	}
+
+	if (cmd != old_cmd) {
+		pci_info(dev, "enabling device (%04x -> %04x)\n", old_cmd, cmd);
+		pci_write_config_word(dev, PCI_COMMAND, cmd);
+	}
+	return 0;
+}