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authorBjorn Helgaas <bhelgaas@google.com>2017-04-28 10:34:29 -0500
committerBjorn Helgaas <bhelgaas@google.com>2017-04-28 10:34:29 -0500
commit78f098383a7abb1eb9dfd45346773fe80a65f05a (patch)
treed9d3958960cefe5206fb2df9dff78aac450ec2c4 /drivers/pci
parentacc886ec934980a45ae8962dbe88e221a40c77a2 (diff)
parente3adec72a3c50b733eb277a9f93c044f59ff55eb (diff)
downloadlinux-78f098383a7abb1eb9dfd45346773fe80a65f05a.tar.bz2
Merge branch 'pci/resource' into next
* pci/resource: PCI: Don't resize resources when realigning all devices in system PCI: Don't reassign resources that are already aligned PCI: Factor pci_reassigndev_resource_alignment() powerpc/powernv: Override pcibios_default_alignment() to force PCI devices to be page aligned PCI: Add pcibios_default_alignment() for arch-specific alignment control PCI: Fix calculation of bridge window's size and alignment PCI: Ignore requested alignment for IOV BARs PCI: Make PCI_ROM_ADDRESS_MASK a 32-bit constant
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/pci.c108
-rw-r--r--drivers/pci/probe.c2
-rw-r--r--drivers/pci/setup-bus.c4
-rw-r--r--drivers/pci/setup-res.c2
4 files changed, 86 insertions, 30 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 2f8f0f516305..2363922b3b95 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5036,6 +5036,11 @@ void pci_ignore_hotplug(struct pci_dev *dev)
}
EXPORT_SYMBOL_GPL(pci_ignore_hotplug);
+resource_size_t __weak pcibios_default_alignment(void)
+{
+ return 0;
+}
+
#define RESOURCE_ALIGNMENT_PARAM_SIZE COMMAND_LINE_SIZE
static char resource_alignment_param[RESOURCE_ALIGNMENT_PARAM_SIZE] = {0};
static DEFINE_SPINLOCK(resource_alignment_lock);
@@ -5043,22 +5048,25 @@ static DEFINE_SPINLOCK(resource_alignment_lock);
/**
* pci_specified_resource_alignment - get resource alignment specified by user.
* @dev: the PCI device to get
+ * @resize: whether or not to change resources' size when reassigning alignment
*
* RETURNS: Resource alignment if it is specified.
* Zero if it is not specified.
*/
-static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
+static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
+ bool *resize)
{
int seg, bus, slot, func, align_order, count;
unsigned short vendor, device, subsystem_vendor, subsystem_device;
- resource_size_t align = 0;
+ resource_size_t align = pcibios_default_alignment();
char *p;
spin_lock(&resource_alignment_lock);
p = resource_alignment_param;
- if (!*p)
+ if (!*p && !align)
goto out;
if (pci_has_flag(PCI_PROBE_ONLY)) {
+ align = 0;
pr_info_once("PCI: Ignoring requested alignments (PCI_PROBE_ONLY)\n");
goto out;
}
@@ -5088,6 +5096,7 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
(!device || (device == dev->device)) &&
(!subsystem_vendor || (subsystem_vendor == dev->subsystem_vendor)) &&
(!subsystem_device || (subsystem_device == dev->subsystem_device))) {
+ *resize = true;
if (align_order == -1)
align = PAGE_SIZE;
else
@@ -5113,6 +5122,7 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev)
bus == dev->bus->number &&
slot == PCI_SLOT(dev->devfn) &&
func == PCI_FUNC(dev->devfn)) {
+ *resize = true;
if (align_order == -1)
align = PAGE_SIZE;
else
@@ -5132,6 +5142,68 @@ out:
return align;
}
+static void pci_request_resource_alignment(struct pci_dev *dev, int bar,
+ resource_size_t align, bool resize)
+{
+ struct resource *r = &dev->resource[bar];
+ resource_size_t size;
+
+ if (!(r->flags & IORESOURCE_MEM))
+ return;
+
+ if (r->flags & IORESOURCE_PCI_FIXED) {
+ dev_info(&dev->dev, "BAR%d %pR: ignoring requested alignment %#llx\n",
+ bar, r, (unsigned long long)align);
+ return;
+ }
+
+ size = resource_size(r);
+ if (size >= align)
+ return;
+
+ /*
+ * Increase the alignment of the resource. There are two ways we
+ * can do this:
+ *
+ * 1) Increase the size of the resource. BARs are aligned on their
+ * size, so when we reallocate space for this resource, we'll
+ * allocate it with the larger alignment. This also prevents
+ * assignment of any other BARs inside the alignment region, so
+ * if we're requesting page alignment, this means no other BARs
+ * will share the page.
+ *
+ * The disadvantage is that this makes the resource larger than
+ * the hardware BAR, which may break drivers that compute things
+ * based on the resource size, e.g., to find registers at a
+ * fixed offset before the end of the BAR.
+ *
+ * 2) Retain the resource size, but use IORESOURCE_STARTALIGN and
+ * set r->start to the desired alignment. By itself this
+ * doesn't prevent other BARs being put inside the alignment
+ * region, but if we realign *every* resource of every device in
+ * the system, none of them will share an alignment region.
+ *
+ * When the user has requested alignment for only some devices via
+ * the "pci=resource_alignment" argument, "resize" is true and we
+ * use the first method. Otherwise we assume we're aligning all
+ * devices and we use the second.
+ */
+
+ dev_info(&dev->dev, "BAR%d %pR: requesting alignment to %#llx\n",
+ bar, r, (unsigned long long)align);
+
+ if (resize) {
+ r->start = 0;
+ r->end = align - 1;
+ } else {
+ r->flags &= ~IORESOURCE_SIZEALIGN;
+ r->flags |= IORESOURCE_STARTALIGN;
+ r->start = align;
+ r->end = r->start + size - 1;
+ }
+ r->flags |= IORESOURCE_UNSET;
+}
+
/*
* This function disables memory decoding and releases memory resources
* of the device specified by kernel's boot parameter 'pci=resource_alignment='.
@@ -5143,8 +5215,9 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
{
int i;
struct resource *r;
- resource_size_t align, size;
+ resource_size_t align;
u16 command;
+ bool resize = false;
/*
* VF BARs are read-only zero according to SR-IOV spec r1.1, sec
@@ -5156,7 +5229,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
return;
/* check if specified PCI is target device to reassign */
- align = pci_specified_resource_alignment(dev);
+ align = pci_specified_resource_alignment(dev, &resize);
if (!align)
return;
@@ -5173,28 +5246,11 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)
command &= ~PCI_COMMAND_MEMORY;
pci_write_config_word(dev, PCI_COMMAND, command);
- for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
- r = &dev->resource[i];
- if (!(r->flags & IORESOURCE_MEM))
- continue;
- if (r->flags & IORESOURCE_PCI_FIXED) {
- dev_info(&dev->dev, "Ignoring requested alignment for BAR%d: %pR\n",
- i, r);
- continue;
- }
+ for (i = 0; i <= PCI_ROM_RESOURCE; i++)
+ pci_request_resource_alignment(dev, i, align, resize);
- size = resource_size(r);
- if (size < align) {
- size = align;
- dev_info(&dev->dev,
- "Rounding up size of resource #%d to %#llx.\n",
- i, (unsigned long long)size);
- }
- r->flags |= IORESOURCE_UNSET;
- r->end = size - 1;
- r->start = 0;
- }
- /* Need to disable bridge's resource window,
+ /*
+ * Need to disable bridge's resource window,
* to enable the kernel to reassign new resource
* window later on.
*/
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index f2bd0024cb88..5548044afb5b 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -231,7 +231,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
res->flags |= IORESOURCE_ROM_ENABLE;
l64 = l & PCI_ROM_ADDRESS_MASK;
sz64 = sz & PCI_ROM_ADDRESS_MASK;
- mask64 = (u32)PCI_ROM_ADDRESS_MASK;
+ mask64 = PCI_ROM_ADDRESS_MASK;
}
if (res->flags & IORESOURCE_MEM_64) {
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index cb389277df41..958da7db9033 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1066,10 +1066,10 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
r->flags = 0;
continue;
}
- size += r_size;
+ size += max(r_size, align);
/* Exclude ranges with size > align from
calculation of the alignment. */
- if (r_size == align)
+ if (r_size <= align)
aligns[order] += align;
if (order > max_order)
max_order = order;
diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 4bc589ee78d0..85774b7a316a 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -63,7 +63,7 @@ static void pci_std_update_resource(struct pci_dev *dev, int resno)
mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
new |= res->flags & ~PCI_BASE_ADDRESS_IO_MASK;
} else if (resno == PCI_ROM_RESOURCE) {
- mask = (u32)PCI_ROM_ADDRESS_MASK;
+ mask = PCI_ROM_ADDRESS_MASK;
} else {
mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
new |= res->flags & ~PCI_BASE_ADDRESS_MEM_MASK;