[PATCH 00/11] pci: update pci bridge resources

[PATCH 00/11] pci: update pci bridge resources

[Yinghai Lu]

this patchset is trying to update pci bridge BAR when that BAR is big enough.

1. boot time:

BIOS separate IO range between several IOHs, and on some slots, BIOS assign
the resource to the bridge, but stop assigning resource to the device under
that bridge, because the device need big resource.

so patches (first 8) are trying to
a. pci assign unassign and record the failed device resource.
b. clear the BIOS assigned resource of the parent bridge of fail device
c. go back and call pci assign unsigned
d. if it still fail, will go up more bridges. and clear and try again.

v2: Jesse doesn't like it is in find_free_bus_resource...
    try to move out of pci_bus_size_bridges loop.
v3: add pci_setup_bridge calling after pci_bridge_release_not_used_res.
    only clear release those res for x86.
v4: Bjorn want to release use dev instead of bus.
v5: Kenji pointed out it will have problem with several level bridge.
    so let only handle leaf bridge.
v6: address Kenji's request (new pci_bus_release...). and change applying order
    move back release to pci_assign_unassigned_resource
v7: change functions name pci_bus_release_unused_bridge_res according to Jesse
v8: address Eric's concern, only overwrite leaf bridge resource that is not big
    enough need to do it in two steps, and first step recore the failed res,
    and don't touch bridge res that programmed by firmware. second step will
    try to release bridge resource that is too small at first.
v9: refresh to be applied after bjorn's patch, and remove trick about save
    size and restore resource second try.
v11:add pci=try=5, about more try to change more bridge
v12:not shrink pci bridge resource

2. hotplug:
BIOS separate IO range between several IOHs, and on some slots, BIOS assign
the resource to every bridge. (8M) but when insert one card that big resource,
the card can not get resource. because kernel will not touch the bridge
resource.

so patches (9-11) are trying to
a. assign resource to devices with that slot. and record fail devices
b. if there is some failed, will clear sepcifically io port of bridge, or mmio of bridge, or mmio pref of bridge.
c. try to assign the parent bridge of the slot.

v2: address Alex's concern about pci remove/rescan feature about
    pci_setup_bridge changes.
v3: Kenji pointed out that pci_config_slot need to be called before
    pci_bus_add_devices()
v4: move out pci_is_enabled checkout of pci_setup_bridge()
v5: change the applying sequence.
v6: change the functions name according to Jesse
v8: address Eric's concern, only overwrite leaf bridge resource that is not
     big enough
v9: refresh to be applied after bjorn's patch, and remove trick about save
    size and restore resource second try.
v10:alex found need to have export for pci_assign_unassigned_bridge_resources
v11: pass check_leaf with pci_bus_release_unused_bridge_res

patches (12-13)
will try to shrink, the pci hotplug related pcie port, so could save some for
others.

-v13: change resource_list to resource_list_x, to save size and flags aside,
      otherwise grandchild res will get confused with son's res as could be used

-v14: default it is disabled.  could use pci=try=2 to enable it.
-v15: seperate release_child_resources aside.

-v16: refresh according to new pci/linux-next of 2009_01_15
      change some name according to Jesse

-v17: address Alex's comments

Thanks

Yinghai

[PATCH 01/11] pci: add pci_bridge_release_unused_res and pci_bus_release_unused_bridge_res

[Yinghai Lu]

so later we could use it to release small resource before pci assign unassign res

-v2: change name to release_child_resources according to Jesse
-v3: according to Linus, move release_child_resources to resource.c
     also need to put the lock around them all to avoid recursive deep.
     (my test case only have one level that need to be released)
-v4: seperate release_child_resources to another patch
     according to Bjorn, change hard code 3 to PCI_BRIDGE_RESOURCE_END
-v5: remove unused in the name, and also use enum for release type according
     to Jesse
-v6: use pci_is_root_bus instead acording to ALex.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   95 +++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 95 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 52fbd42..7a18428 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -604,6 +604,101 @@ void __ref pci_bus_assign_resources(const struct pci_bus *bus)
 }
 EXPORT_SYMBOL(pci_bus_assign_resources);
 
+static void pci_bridge_release_resources(struct pci_bus *bus,
+					  unsigned long type)
+{
+	int idx;
+	bool changed = false;
+	struct pci_dev *dev;
+	struct resource *r;
+	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
+				  IORESOURCE_PREFETCH;
+
+	dev = bus->self;
+	for (idx = PCI_BRIDGE_RESOURCES; idx <= PCI_BRIDGE_RESOURCE_END;
+	     idx++) {
+		r = &dev->resource[idx];
+		if ((r->flags & type_mask) != type)
+			continue;
+		if (!r->parent)
+			continue;
+		/*
+		 * if there are children under that, we should release them
+		 *  all
+		 */
+		release_child_resources(r);
+		if (!release_resource(r)) {
+			dev_printk(KERN_DEBUG, &dev->dev,
+				 "resource %d %pR released\n", idx, r);
+			/* keep the old size */
+			r->end = resource_size(r) - 1;
+			r->start = 0;
+			r->flags = 0;
+			changed = true;
+		}
+	}
+
+	if (changed) {
+		if (type & IORESOURCE_PREFETCH) {
+			/* avoiding touch the one without PREF */
+			type = IORESOURCE_PREFETCH;
+		}
+		__pci_setup_bridge(bus, type);
+	}
+}
+
+enum release_type {
+	leaf_only,
+	whole_subtree,
+};
+/*
+ * try to release pci bridge resources that is from leaf bridge,
+ * so we can allocate big new one later
+ */
+static void __ref pci_bus_release_bridge_resources(struct pci_bus *bus,
+						   unsigned long type,
+						   enum release_type rel_type)
+{
+	struct pci_dev *dev;
+	bool is_leaf_bridge = true;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		struct pci_bus *b = dev->subordinate;
+		if (!b)
+			continue;
+
+		switch (dev->class >> 8) {
+		case PCI_CLASS_BRIDGE_CARDBUS:
+			is_leaf_bridge = false;
+			break;
+
+		case PCI_CLASS_BRIDGE_PCI:
+		default:
+			is_leaf_bridge = false;
+			if (rel_type == whole_subtree)
+				pci_bus_release_bridge_resources(b, type,
+							 whole_subtree);
+			break;
+		}
+	}
+
+	/* The root bus? */
+	if (pci_is_root_bus(bus))
+		return;
+
+	switch (bus->self->class >> 8) {
+	case PCI_CLASS_BRIDGE_CARDBUS:
+		break;
+
+	case PCI_CLASS_BRIDGE_PCI:
+	default:
+		if (((rel_type == leaf_only) && is_leaf_bridge) ||
+		    (rel_type == whole_subtree))
+			pci_bridge_release_resources(bus, type);
+		break;
+	}
+}
+
 static void pci_bus_dump_res(struct pci_bus *bus)
 {
         int i;
-- 
1.6.4.2

[PATCH 02/11] pci: add failed_list to record failed one for pci_bus_assign_resources

[Yinghai Lu]

so later we can try to assign resource those failed devices again.

-v2: store start, end, flags aside. so could keep res cleared when assign
     failed. and make following assignment of its children do not go wild
-v3: update comments

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   66 ++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 62 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 7a18428..fa9f4e2 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -27,7 +27,52 @@
 #include <linux/slab.h>
 #include "pci.h"
 
-static void pbus_assign_resources_sorted(const struct pci_bus *bus)
+struct resource_list_x {
+	struct resource_list_x *next;
+	struct resource *res;
+	struct pci_dev *dev;
+	resource_size_t start;
+	resource_size_t end;
+	unsigned long flags;
+};
+
+static void add_to_failed_list(struct resource_list_x *head,
+				 struct pci_dev *dev, struct resource *res)
+{
+	struct resource_list_x *list = head;
+	struct resource_list_x *ln = list->next;
+	struct resource_list_x *tmp;
+
+	tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
+	if (!tmp) {
+		pr_warning("add_to_failed_list: kmalloc() failed!\n");
+		return;
+	}
+
+	tmp->next = ln;
+	tmp->res = res;
+	tmp->dev = dev;
+	tmp->start = res->start;
+	tmp->end = res->end;
+	tmp->flags = res->flags;
+	list->next = tmp;
+}
+
+static void free_failed_list(struct resource_list_x *head)
+{
+	struct resource_list_x *list, *tmp;
+
+	for (list = head->next; list;) {
+		tmp = list;
+		list = list->next;
+		kfree(tmp);
+	}
+
+	head->next = NULL;
+}
+
+static void pbus_assign_resources_sorted(const struct pci_bus *bus,
+					 struct resource_list_x *fail_head)
 {
 	struct pci_dev *dev;
 	struct resource *res;
@@ -58,6 +103,13 @@ static void pbus_assign_resources_sorted(const struct pci_bus *bus)
 		res = list->res;
 		idx = res - &list->dev->resource[0];
 		if (pci_assign_resource(list->dev, idx)) {
+			if (fail_head && !pci_is_root_bus(list->dev->bus)) {
+				/*
+				 * device need to keep flags and size
+				 * for next try
+				 */
+				add_to_failed_list(fail_head, list->dev, res);
+			}
 			res->start = 0;
 			res->end = 0;
 			res->flags = 0;
@@ -572,19 +624,20 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus)
 }
 EXPORT_SYMBOL(pci_bus_size_bridges);
 
-void __ref pci_bus_assign_resources(const struct pci_bus *bus)
+static void __ref __pci_bus_assign_resources(const struct pci_bus *bus,
+					 struct resource_list_x *fail_head)
 {
 	struct pci_bus *b;
 	struct pci_dev *dev;
 
-	pbus_assign_resources_sorted(bus);
+	pbus_assign_resources_sorted(bus, fail_head);
 
 	list_for_each_entry(dev, &bus->devices, bus_list) {
 		b = dev->subordinate;
 		if (!b)
 			continue;
 
-		pci_bus_assign_resources(b);
+		__pci_bus_assign_resources(b, fail_head);
 
 		switch (dev->class >> 8) {
 		case PCI_CLASS_BRIDGE_PCI:
@@ -602,6 +655,11 @@ void __ref pci_bus_assign_resources(const struct pci_bus *bus)
 		}
 	}
 }
+
+void __ref pci_bus_assign_resources(const struct pci_bus *bus)
+{
+	__pci_bus_assign_resources(bus, NULL);
+}
 EXPORT_SYMBOL(pci_bus_assign_resources);
 
 static void pci_bridge_release_resources(struct pci_bus *bus,
-- 
1.6.4.2

[PATCH 03/11] pci: reject mmio range start from 0 on pci_bridge read

[Yinghai Lu]

only need to set the value to resource.
also could keep the old setting in resource for prevent shrink bridge
resources.

-v2: change to "bar reading" to "reg reading"

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/probe.c |   18 +++++++++++++++---
 1 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 11824d7..8cd4fb3 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -316,13 +316,17 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 		limit |= (io_limit_hi << 16);
 	}
 
-	if (base <= limit) {
+	if (base && base <= limit) {
 		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
 		if (!res->start)
 			res->start = base;
 		if (!res->end)
 			res->end = limit + 0xfff;
 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	} else {
+		dev_printk(KERN_DEBUG, &dev->dev,
+			 "  bridge window [io  %04lx - %04lx] reg reading\n",
+				 base, limit);
 	}
 
 	res = child->resource[1];
@@ -330,11 +334,15 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
 	base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
 	limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
-	if (base <= limit) {
+	if (base && base <= limit) {
 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
 		res->start = base;
 		res->end = limit + 0xfffff;
 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	} else {
+		dev_printk(KERN_DEBUG, &dev->dev,
+			"  bridge window [mem 0x%08lx - 0x%08lx] reg reading\n",
+					 base, limit + 0xfffff);
 	}
 
 	res = child->resource[2];
@@ -366,7 +374,7 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 #endif
 		}
 	}
-	if (base <= limit) {
+	if (base && base <= limit) {
 		res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
 					 IORESOURCE_MEM | IORESOURCE_PREFETCH;
 		if (res->flags & PCI_PREF_RANGE_TYPE_64)
@@ -374,6 +382,10 @@ void __devinit pci_read_bridge_bases(struct pci_bus *child)
 		res->start = base;
 		res->end = limit + 0xfffff;
 		dev_printk(KERN_DEBUG, &dev->dev, "  bridge window %pR\n", res);
+	} else {
+		dev_printk(KERN_DEBUG, &dev->dev,
+		     "  bridge window [mem 0x%08lx - %08lx pref] reg reading\n",
+					 base, limit + 0xfffff);
 	}
 }
 
-- 
1.6.4.2

[PATCH 04/11] pci: don't shrink bridge resources

[Yinghai Lu]

when we are clearing leaf bridge resource and try to get big one, we could
shrink the bridge if there is no resource under it.

let check with old resource size and make sure we are trying to get big one.

-v2: keep disable window print out, still could happen on non pci hotplug system

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index fa9f4e2..900ba6f 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -387,7 +387,7 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
 {
 	struct pci_dev *dev;
 	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO);
-	unsigned long size = 0, size1 = 0;
+	unsigned long size = 0, size1 = 0, old_size;
 
 	if (!b_res)
  		return;
@@ -412,12 +412,17 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size)
 	}
 	if (size < min_size)
 		size = min_size;
+	old_size = resource_size(b_res);
+	if (old_size == 1)
+		old_size = 0;
 /* To be fixed in 2.5: we should have sort of HAVE_ISA
    flag in the struct pci_bus. */
 #if defined(CONFIG_ISA) || defined(CONFIG_EISA)
 	size = (size & 0xff) + ((size & ~0xffUL) << 2);
 #endif
 	size = ALIGN(size + size1, 4096);
+	if (size < old_size)
+		size = old_size;
 	if (!size) {
 		if (b_res->start || b_res->end)
 			dev_info(&bus->self->dev, "disabling bridge window "
@@ -438,7 +443,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 			 unsigned long type, resource_size_t min_size)
 {
 	struct pci_dev *dev;
-	resource_size_t min_align, align, size;
+	resource_size_t min_align, align, size, old_size;
 	resource_size_t aligns[12];	/* Alignments from 1Mb to 2Gb */
 	int order, max_order;
 	struct resource *b_res = find_free_bus_resource(bus, type);
@@ -488,6 +493,11 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 	}
 	if (size < min_size)
 		size = min_size;
+	old_size = resource_size(b_res);
+	if (old_size == 1)
+		old_size = 0;
+	if (size < old_size)
+		size = old_size;
 
 	align = 0;
 	min_align = 0;
-- 
1.6.4.2

[PATCH 05/11] pci: update bridge res to get more big range in pci assign unssign

[Yinghai Lu]

BIOS separate IO range between several IOHs, and on some slots, BIOS assign the
resource to the bridge, but stop assigning resource to the device under that
bridge, because the device need big resource.

1. pci assign unassign and record the failed device resource.
2. clear the BIOS assigned resource of the parent bridge of fail device
3. go back and call pci assign unsigned
4. if it still fail, will go up more bridges. and clear and try again.

use pci_try_num to control back track bridge levels.

-v2: update it with resource_list_x
-v3: make pci_try_num default to 1. and when pci_try_num is set to more than 1
     will check it with max_depth, and adjust that to make sure it is bigger
     enough
-v4: update to enum release_type and _used_calling
-v5: seems all doesn't like pci=try=N at this point, let remove it at first

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |  113 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 112 insertions(+), 1 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 900ba6f..ed13de6 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -798,11 +798,65 @@ static void pci_bus_dump_resources(struct pci_bus *bus)
 	}
 }
 
+static int __init pci_bus_get_depth(struct pci_bus *bus)
+{
+	int depth = 0;
+	struct pci_dev *dev;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		int ret;
+		struct pci_bus *b = dev->subordinate;
+		if (!b)
+			continue;
+
+		ret = pci_bus_get_depth(b);
+		if (ret + 1 > depth)
+			depth = ret + 1;
+	}
+
+	return depth;
+}
+static int __init pci_get_max_depth(void)
+{
+	int depth = 0;
+	struct pci_bus *bus;
+
+	list_for_each_entry(bus, &pci_root_buses, node) {
+		int ret;
+
+		ret = pci_bus_get_depth(bus);
+		if (ret > depth)
+			depth = ret;
+	}
+
+	return depth;
+}
+
+/*
+ * first try will not touch pci bridge res
+ * second  and later try will clear small leaf bridge res
+ * will stop till to the max  deepth if can not find good one
+ */
 void __init
 pci_assign_unassigned_resources(void)
 {
 	struct pci_bus *bus;
+	int tried_times = 0;
+	enum release_type rel_type = leaf_only;
+	struct resource_list_x head, *list;
+	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
+				  IORESOURCE_PREFETCH;
+	unsigned long failed_type;
+	int max_depth = pci_get_max_depth();
+	int pci_try_num;
+
+	head.next = NULL;
 
+	pci_try_num = max_depth + 1;
+	printk(KERN_DEBUG "PCI: max bus depth: %d pci_try_num: %d\n",
+		 max_depth, pci_try_num);
+
+again:
 	/* Depth first, calculate sizes and alignments of all
 	   subordinate buses. */
 	list_for_each_entry(bus, &pci_root_buses, node) {
@@ -810,7 +864,64 @@ pci_assign_unassigned_resources(void)
 	}
 	/* Depth last, allocate resources and update the hardware. */
 	list_for_each_entry(bus, &pci_root_buses, node) {
-		pci_bus_assign_resources(bus);
+		__pci_bus_assign_resources(bus, &head);
+	}
+	tried_times++;
+
+	/* any device complain? */
+	if (!head.next)
+		goto enable_and_dump;
+	failed_type = 0;
+	for (list = head.next; list;) {
+		failed_type |= list->flags;
+		list = list->next;
+	}
+	/*
+	 * io port are tight, don't try extra
+	 * or if reach the limit, don't want to try more
+	 */
+	failed_type &= type_mask;
+	if ((failed_type == IORESOURCE_IO) || (tried_times >= pci_try_num)) {
+		free_failed_list(&head);
+		goto enable_and_dump;
+	}
+
+	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
+			 tried_times + 1);
+
+	/* third times and later will not check if it is leaf */
+	if ((tried_times + 1) > 2)
+		rel_type = whole_subtree;
+
+	/*
+	 * Try to release leaf bridge's resources that doesn't fit resource of
+	 * child device under that bridge
+	 */
+	for (list = head.next; list;) {
+		bus = list->dev->bus;
+		pci_bus_release_bridge_resources(bus, list->flags & type_mask,
+						  rel_type);
+		list = list->next;
+	}
+	/* retore size and flags */
+	for (list = head.next; list;) {
+		struct resource *res = list->res;
+
+		res->start = list->start;
+		res->end = list->end;
+		res->flags = list->flags;
+		if (list->dev->subordinate)
+			res->flags = 0;
+
+		list = list->next;
+	}
+	free_failed_list(&head);
+
+	goto again;
+
+enable_and_dump:
+	/* Depth last, update the hardware. */
+	list_for_each_entry(bus, &pci_root_buses, node) {
 		pci_enable_bridges(bus);
 	}
 
-- 
1.6.4.2

[PATCH 06/11] pci: introduce pci_assign_unassigned_bridge_resources

[Yinghai Lu]

for pciehp to use it later

pci_setup_bridge() will not check enabled for the slot bridge, otherwise
update res is not updated to bridge BAR. that is bridge is enabled already for
port service.

-v2: update it with resource_list_x
-v3: remove the clear busmaster. according to Kenji
-v4: make pdev_assign_resources_sorted and pbus_assign_resources_sorted share two small functions
     according to Alex.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |  118 +++++++++++++++++++++++++++++++++++-----------
 include/linux/pci.h     |    1 +
 2 files changed, 91 insertions(+), 28 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index ed13de6..e56b198 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -71,42 +71,41 @@ static void free_failed_list(struct resource_list_x *head)
 	head->next = NULL;
 }
 
-static void pbus_assign_resources_sorted(const struct pci_bus *bus,
-					 struct resource_list_x *fail_head)
+static void __dev_sort_resources(struct pci_dev *dev,
+				 struct resource_list *head)
 {
-	struct pci_dev *dev;
-	struct resource *res;
-	struct resource_list head, *list, *tmp;
-	int idx;
+	u16 class = dev->class >> 8;
 
-	head.next = NULL;
-	list_for_each_entry(dev, &bus->devices, bus_list) {
-		u16 class = dev->class >> 8;
+	/* Don't touch classless devices or host bridges or ioapics.  */
+	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
+		return;
 
-		/* Don't touch classless devices or host bridges or ioapics.  */
-		if (class == PCI_CLASS_NOT_DEFINED ||
-		    class == PCI_CLASS_BRIDGE_HOST)
-			continue;
+	/* Don't touch ioapic devices already enabled by firmware */
+	if (class == PCI_CLASS_SYSTEM_PIC) {
+		u16 command;
+		pci_read_config_word(dev, PCI_COMMAND, &command);
+		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
+			return;
+	}
 
-		/* Don't touch ioapic devices already enabled by firmware */
-		if (class == PCI_CLASS_SYSTEM_PIC) {
-			u16 command;
-			pci_read_config_word(dev, PCI_COMMAND, &command);
-			if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
-				continue;
-		}
+	pdev_sort_resources(dev, head);
+}
 
-		pdev_sort_resources(dev, &head);
-	}
+static void __assign_resources_sorted(struct resource_list *head,
+				 struct resource_list_x *fail_head)
+{
+	struct resource *res;
+	struct resource_list *list, *tmp;
+	int idx;
 
-	for (list = head.next; list;) {
+	for (list = head->next; list;) {
 		res = list->res;
 		idx = res - &list->dev->resource[0];
 		if (pci_assign_resource(list->dev, idx)) {
 			if (fail_head && !pci_is_root_bus(list->dev->bus)) {
 				/*
 				 * device need to keep flags and size
-				 * for next try
+				 * for second try
 				 */
 				add_to_failed_list(fail_head, list->dev, res);
 			}
@@ -120,6 +119,30 @@ static void pbus_assign_resources_sorted(const struct pci_bus *bus,
 	}
 }
 
+static void pdev_assign_resources_sorted(struct pci_dev *dev,
+				 struct resource_list_x *fail_head)
+{
+	struct resource_list head;
+
+	head.next = NULL;
+	__dev_sort_resources(dev, &head);
+	__assign_resources_sorted(&head, fail_head);
+
+}
+
+static void pbus_assign_resources_sorted(const struct pci_bus *bus,
+					 struct resource_list_x *fail_head)
+{
+	struct pci_dev *dev;
+	struct resource_list head;
+
+	head.next = NULL;
+	list_for_each_entry(dev, &bus->devices, bus_list)
+		__dev_sort_resources(dev, &head);
+
+	__assign_resources_sorted(&head, fail_head);
+}
+
 void pci_setup_cardbus(struct pci_bus *bus)
 {
 	struct pci_dev *bridge = bus->self;
@@ -278,9 +301,6 @@ static void __pci_setup_bridge(struct pci_bus *bus, unsigned long type)
 {
 	struct pci_dev *bridge = bus->self;
 
-	if (pci_is_enabled(bridge))
-		return;
-
 	dev_info(&bridge->dev, "PCI bridge to [bus %02x-%02x]\n",
 		 bus->secondary, bus->subordinate);
 
@@ -651,7 +671,8 @@ static void __ref __pci_bus_assign_resources(const struct pci_bus *bus,
 
 		switch (dev->class >> 8) {
 		case PCI_CLASS_BRIDGE_PCI:
-			pci_setup_bridge(b);
+			if (!pci_is_enabled(dev))
+				pci_setup_bridge(b);
 			break;
 
 		case PCI_CLASS_BRIDGE_CARDBUS:
@@ -672,6 +693,34 @@ void __ref pci_bus_assign_resources(const struct pci_bus *bus)
 }
 EXPORT_SYMBOL(pci_bus_assign_resources);
 
+static void __ref __pci_bridge_assign_resources(const struct pci_dev *bridge,
+					 struct resource_list_x *fail_head)
+{
+	struct pci_bus *b;
+
+	pdev_assign_resources_sorted((struct pci_dev *)bridge, fail_head);
+
+	b = bridge->subordinate;
+	if (!b)
+		return;
+
+	__pci_bus_assign_resources(b, fail_head);
+
+	switch (bridge->class >> 8) {
+	case PCI_CLASS_BRIDGE_PCI:
+		pci_setup_bridge(b);
+		break;
+
+	case PCI_CLASS_BRIDGE_CARDBUS:
+		pci_setup_cardbus(b);
+		break;
+
+	default:
+		dev_info(&bridge->dev, "not setting up bridge for bus "
+			 "%04x:%02x\n", pci_domain_nr(b), b->number);
+		break;
+	}
+}
 static void pci_bridge_release_resources(struct pci_bus *bus,
 					  unsigned long type)
 {
@@ -930,3 +979,16 @@ enable_and_dump:
 		pci_bus_dump_resources(bus);
 	}
 }
+
+void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
+{
+	struct pci_bus *parent = bridge->subordinate;
+	int retval;
+
+	pci_bus_size_bridges(parent);
+	__pci_bridge_assign_resources(bridge, NULL);
+	retval = pci_reenable_device(bridge);
+	pci_set_master(bridge);
+	pci_enable_bridges(parent);
+}
+EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6b2949c..0e240ed 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -806,6 +806,7 @@ void pci_bus_assign_resources(const struct pci_bus *bus);
 void pci_bus_size_bridges(struct pci_bus *bus);
 int pci_claim_resource(struct pci_dev *, int);
 void pci_assign_unassigned_resources(void);
+void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge);
 void pdev_enable_device(struct pci_dev *);
 void pdev_sort_resources(struct pci_dev *, struct resource_list *);
 int pci_enable_resources(struct pci_dev *, int mask);
-- 
1.6.4.2

[PATCH 07/11] pci: pciehp clean flow in pciehp_configure_device

[Yinghai Lu]

move out bus_size_bridges and assign resources out of pciehp_add_bridge()
and at last do them all together one time including slot bridge, to avoid to
call assign resources several times, when there are several bridges under the
slot bridge.
use pci_assign_nassigned_bridge_resources

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/hotplug/pciehp_pci.c |   23 +++++++++++++++++------
 1 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 2173310..0a16444 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -53,17 +53,15 @@ static int __ref pciehp_add_bridge(struct pci_dev *dev)
 		busnr = pci_scan_bridge(parent, dev, busnr, pass);
 	if (!dev->subordinate)
 		return -1;
-	pci_bus_size_bridges(dev->subordinate);
-	pci_bus_assign_resources(parent);
-	pci_enable_bridges(parent);
-	pci_bus_add_devices(parent);
+
 	return 0;
 }
 
 int pciehp_configure_device(struct slot *p_slot)
 {
 	struct pci_dev *dev;
-	struct pci_bus *parent = p_slot->ctrl->pcie->port->subordinate;
+	struct pci_dev *bridge = p_slot->ctrl->pcie->port;
+	struct pci_bus *parent = bridge->subordinate;
 	int num, fn;
 	struct controller *ctrl = p_slot->ctrl;
 
@@ -96,12 +94,25 @@ int pciehp_configure_device(struct slot *p_slot)
 				(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
 			pciehp_add_bridge(dev);
 		}
+		pci_dev_put(dev);
+	}
+
+	pci_assign_unassigned_bridge_resources(bridge);
+
+	for (fn = 0; fn < 8; fn++) {
+		dev = pci_get_slot(parent, PCI_DEVFN(0, fn));
+		if (!dev)
+			continue;
+		if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
+			pci_dev_put(dev);
+			continue;
+		}
 		pci_configure_slot(dev);
 		pci_dev_put(dev);
 	}
 
-	pci_bus_assign_resources(parent);
 	pci_bus_add_devices(parent);
+
 	return 0;
 }
 
-- 
1.6.4.2

[PATCH 08/11] pci: pciehp second try to get big range for pcie devices

[Yinghai Lu]

handle the case the slot bridge that doesn't get pre-allocated big enough
resources from FW.
for example pcie devices need 256M, but the bridge only get preallocated 2M...

-v2: use resource_list_x
-v3: use tried_times instead of second tried...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   52 ++++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 51 insertions(+), 1 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index e56b198..1966b5e 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -983,12 +983,62 @@ enable_and_dump:
 void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)
 {
 	struct pci_bus *parent = bridge->subordinate;
+	int tried_times = 0;
+	struct resource_list_x head, *list;
 	int retval;
+	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
+				  IORESOURCE_PREFETCH;
+
+	head.next = NULL;
 
+again:
 	pci_bus_size_bridges(parent);
-	__pci_bridge_assign_resources(bridge, NULL);
+	__pci_bridge_assign_resources(bridge, &head);
 	retval = pci_reenable_device(bridge);
 	pci_set_master(bridge);
 	pci_enable_bridges(parent);
+
+	tried_times++;
+
+	/* any device complain? */
+	if (!head.next)
+		return;
+
+	if (tried_times  >= 2) {
+		/* still fail, don't need to try more */
+		free_failed_list(&head);
+		return;
+	}
+
+	printk(KERN_DEBUG "PCI: No. %d try to assign unassigned res\n",
+			 tried_times + 1);
+
+	/*
+	 * Try to release leaf bridge's resources that doesn't fit resource of
+	 * child device under that bridge
+	 */
+	for (list = head.next; list;) {
+		struct pci_bus *bus = list->dev->bus;
+		unsigned long flags = list->flags;
+
+		pci_bus_release_bridge_resources(bus, flags & type_mask,
+						 whole_subtree);
+		list = list->next;
+	}
+	/* retore size and flags */
+	for (list = head.next; list;) {
+		struct resource *res = list->res;
+
+		res->start = list->start;
+		res->end = list->end;
+		res->flags = list->flags;
+		if (list->dev->subordinate)
+			res->flags = 0;
+
+		list = list->next;
+	}
+	free_failed_list(&head);
+
+	goto again;
 }
 EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
-- 
1.6.4.2

[PATCH 09/11] pci: pci_bridge_release_res

[Yinghai Lu]

prepare for pciehp_realloc

it will clear the resource size for bridge

-v2: patrick Keller pointed out need to export it...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   77 ++++++++++++++++++++++++++++++++++++++--------
 include/linux/pci.h     |    1 +
 2 files changed, 64 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 1966b5e..61f128b 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -721,8 +721,9 @@ static void __ref __pci_bridge_assign_resources(const struct pci_dev *bridge,
 		break;
 	}
 }
-static void pci_bridge_release_resources(struct pci_bus *bus,
-					  unsigned long type)
+
+static void __pci_bridge_release_res(struct pci_bus *bus, bool rel_child,
+					 unsigned long type)
 {
 	int idx;
 	bool changed = false;
@@ -731,32 +732,57 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
 				  IORESOURCE_PREFETCH;
 
+	/* The root bus? */
+	if (!bus->self)
+		return;
+
+	/* for pci bridges res only */
 	dev = bus->self;
-	for (idx = PCI_BRIDGE_RESOURCES; idx <= PCI_BRIDGE_RESOURCE_END;
+	if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
+		return;
+
+	for (idx = PCI_BRIDGE_RESOURCES; idx < PCI_BRIDGE_RESOURCES + 3;
 	     idx++) {
 		r = &dev->resource[idx];
-		if ((r->flags & type_mask) != type)
-			continue;
 		if (!r->parent)
 			continue;
-		/*
-		 * if there are children under that, we should release them
-		 *  all
-		 */
-		release_child_resources(r);
+
+		if (type != type_mask && (r->flags & type_mask) != type)
+			continue;
+
+		if (rel_child) {
+			/*
+			 * if there are children under that, we should release
+			 *  them all
+			 */
+			release_child_resources(r);
+		} else {
+			/*
+			 * if there are children under that, we should not
+			 * release it
+			 */
+			if (r->child)
+				continue;
+		}
+
 		if (!release_resource(r)) {
 			dev_printk(KERN_DEBUG, &dev->dev,
 				 "resource %d %pR released\n", idx, r);
-			/* keep the old size */
-			r->end = resource_size(r) - 1;
-			r->start = 0;
+			if (rel_child) {
+				/* keep the old size */
+				r->end = resource_size(r) - 1;
+			} else {
+				/* old size is not kept */
+				r->start = 0;
+			}
+			r->end   = 0;
 			r->flags = 0;
 			changed = true;
 		}
 	}
 
 	if (changed) {
-		if (type & IORESOURCE_PREFETCH) {
+		if (type != type_mask && (type & IORESOURCE_PREFETCH)) {
 			/* avoiding touch the one without PREF */
 			type = IORESOURCE_PREFETCH;
 		}
@@ -764,6 +790,29 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
 	}
 }
 
+/*
+ * pci_bridge_release_res will not release the resource that have children
+ *  and apply all resources type under that devices
+ */
+void pci_bridge_release_res(struct pci_bus *bus)
+{
+	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
+				  IORESOURCE_PREFETCH;
+
+	__pci_bridge_release_res(bus, false, type_mask);
+}
+EXPORT_SYMBOL_GPL(pci_bridge_release_res);
+
+/*
+ * this one will release children resource, but only to specifed resource type
+ * and also will keep old resource size
+ */
+static void pci_bridge_release_resources(struct pci_bus *bus,
+					  unsigned long type)
+{
+	__pci_bridge_release_res(bus, true, type);
+}
+
 enum release_type {
 	leaf_only,
 	whole_subtree,
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 0e240ed..b8c7e45 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -805,6 +805,7 @@ int pci_vpd_truncate(struct pci_dev *dev, size_t size);
 void pci_bus_assign_resources(const struct pci_bus *bus);
 void pci_bus_size_bridges(struct pci_bus *bus);
 int pci_claim_resource(struct pci_dev *, int);
+void pci_bridge_release_res(struct pci_bus *bus);
 void pci_assign_unassigned_resources(void);
 void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge);
 void pdev_enable_device(struct pci_dev *);
-- 
1.6.4.2

[PATCH 10/11] pciehp: add support for bridge resource reallocation

[Yinghai Lu]

From: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>

With this patch, pciehp driver try to clear PCI bridge resources to
parent bridge (root port or switch downstream port) of the slot

so we can shrink pci bridge resource for those port

This feature is enabled when 'pciehp_realloc' option is specified.

-v2: make it could be appiled after Yinghai patchset that touch pci bridge
     resource also remove poweron check, because pci_bridge_release_res will
     check child at first

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/hotplug/pciehp.h      |    1 +
 drivers/pci/hotplug/pciehp_core.c |    7 +++++++
 drivers/pci/hotplug/pciehp_pci.c  |    4 ++++
 3 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 4ed76b4..78cf0f4 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -43,6 +43,7 @@ extern int pciehp_poll_mode;
 extern int pciehp_poll_time;
 extern int pciehp_debug;
 extern int pciehp_force;
+extern int pciehp_realloc;
 extern struct workqueue_struct *pciehp_wq;
 
 #define dbg(format, arg...)						\
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 920f820..8f990ad 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -41,6 +41,7 @@ int pciehp_debug;
 int pciehp_poll_mode;
 int pciehp_poll_time;
 int pciehp_force;
+int pciehp_realloc;
 struct workqueue_struct *pciehp_wq;
 
 #define DRIVER_VERSION	"0.4"
@@ -55,10 +56,12 @@ module_param(pciehp_debug, bool, 0644);
 module_param(pciehp_poll_mode, bool, 0644);
 module_param(pciehp_poll_time, int, 0644);
 module_param(pciehp_force, bool, 0644);
+module_param(pciehp_realloc, bool, 0644);
 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if _OSC and OSHP are missing");
+MODULE_PARM_DESC(pciehp_realloc, "Realloc resources for slot's parent bridge");
 
 #define PCIE_MODULE_NAME "pciehp"
 
@@ -272,6 +275,10 @@ static int pciehp_probe(struct pcie_device *dev)
 	if (!occupied && poweron && POWER_CTRL(ctrl))
 		pciehp_power_off_slot(slot);
 
+	/* Release I/O window of the slots's parent bridge */
+	if (pciehp_realloc)
+		pci_bridge_release_res(dev->port->subordinate);
+
 	return 0;
 
 err_out_free_ctrl_slot:
diff --git a/drivers/pci/hotplug/pciehp_pci.c b/drivers/pci/hotplug/pciehp_pci.c
index 0a16444..f6119e4 100644
--- a/drivers/pci/hotplug/pciehp_pci.c
+++ b/drivers/pci/hotplug/pciehp_pci.c
@@ -166,5 +166,9 @@ int pciehp_unconfigure_device(struct slot *p_slot)
 		pci_dev_put(temp);
 	}
 
+	/* Release I/O window of the slots's parent bridge */
+	if (pciehp_realloc)
+		pci_bridge_release_res(parent);
+
 	return rc;
 }
-- 
1.6.4.2

[PATCH 11/11] pci: set PCI_PREF_RANGE_TYPE_64 in pci_bridge_check_ranges

[Yinghai Lu]

make pci_bridge_check_ranges() to store the PCI_PREF_RANGE_TYPE_64 in addition
to IORESOURCE_MEM_64. just like pci_read_bridge_bases()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 61f128b..5b3fe2c 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -359,8 +359,11 @@ static void pci_bridge_check_ranges(struct pci_bus *bus)
 	}
 	if (pmem) {
 		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH;
-		if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64)
+		if ((pmem & PCI_PREF_RANGE_TYPE_MASK) ==
+		    PCI_PREF_RANGE_TYPE_64) {
 			b_res[2].flags |= IORESOURCE_MEM_64;
+			b_res[2].flags |= PCI_PREF_RANGE_TYPE_64;
+		}
 	}
 
 	/* double check if bridge does support 64 bit pref */
-- 
1.6.4.2

Re: [PATCH 01/11] pci: add pci_bridge_release_unused_res and pci_bus_release_unused_bridge_res

[Alex Chiang]

> +static void __ref pci_bus_release_bridge_resources(struct pci_bus *bus,
> +						   unsigned long type,
> +						   enum release_type rel_type)
> +{
> +	struct pci_dev *dev;
> +	bool is_leaf_bridge = true;
> +
> +	list_for_each_entry(dev, &bus->devices, bus_list) {
> +		struct pci_bus *b = dev->subordinate;
> +		if (!b)
> +			continue;
> +
> +		switch (dev->class >> 8) {
> +		case PCI_CLASS_BRIDGE_CARDBUS:
> +			is_leaf_bridge = false;
> +			break;
> +
> +		case PCI_CLASS_BRIDGE_PCI:
> +		default:
> +			is_leaf_bridge = false;
> +			if (rel_type == whole_subtree)
> +				pci_bus_release_bridge_resources(b, type,
> +							 whole_subtree);
> +			break;
> +		}
> +	}

I still don't understand this loop. Can't you write it like this:

	list_for_each_entry(dev, &bus->devices, bus_list) {
		struct pci_bus *b = dev->subordinate;
		if (!b)
			continue;

		is_leaf_bridge = false;

		if ((dev->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS)
			continue;

		if (rel_type == whole_subtree)
			pci_bus_release_bridge_resources(b, type,
						whole_subtree);
	}

I'm looking at that 'default' label in your switch() statement
which causes us to always set is_leaf_bridge = false after 'b' is
valid.

/ac

Re: [PATCH 05/11] pci: update bridge res to get more big range in pci assign unssign

[Alex Chiang]

> +	/* retore size and flags */

"restore"

> +	for (list = head.next; list;) {
> +		struct resource *res = list->res;
> +
> +		res->start = list->start;
> +		res->end = list->end;
> +		res->flags = list->flags;
> +		if (list->dev->subordinate)
> +			res->flags = 0;
> +
> +		list = list->next;
> +	}
> +	free_failed_list(&head);
> +
> +	goto again;
> +
> +enable_and_dump:
> +	/* Depth last, update the hardware. */
> +	list_for_each_entry(bus, &pci_root_buses, node) {
>  		pci_enable_bridges(bus);
>  	}

Strictly speaking, you don't need these curly braces.

/ac

Re: [PATCH 09/11] pci: pci_bridge_release_res

[Alex Chiang]

> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -731,32 +732,57 @@ static void pci_bridge_release_resources(struct pci_bus *bus,
>  	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
>  				  IORESOURCE_PREFETCH;
>  
> +	/* The root bus? */
> +	if (!bus->self)
> +		return;
> +

pci_is_root_bus()

> +/*
> + * pci_bridge_release_res will not release the resource that have children
> + *  and apply all resources type under that devices
> + */
> +void pci_bridge_release_res(struct pci_bus *bus)
> +{
> +	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
> +				  IORESOURCE_PREFETCH;
> +
> +	__pci_bridge_release_res(bus, false, type_mask);
> +}
> +EXPORT_SYMBOL_GPL(pci_bridge_release_res);
> +
> +/*
> + * this one will release children resource, but only to specifed resource type
> + * and also will keep old resource size
> + */
> +static void pci_bridge_release_resources(struct pci_bus *bus,
> +					  unsigned long type)
> +{
> +	__pci_bridge_release_res(bus, true, type);
> +}
> +

I still don't really like the naming here. We're exporting a
function with an abbreviation in the name while the static
function has a name that is more descriptive.

/ac

Re: [PATCH 05/11] pci: update bridge res to get more big range in pci assign unssign

[Yinghai Lu]

On 01/19/2010 01:48 PM, Alex Chiang wrote:
>> +	/* retore size and flags */
> 
> "restore"
> 
>> +	for (list = head.next; list;) {
>> +		struct resource *res = list->res;
>> +
>> +		res->start = list->start;
>> +		res->end = list->end;
>> +		res->flags = list->flags;
>> +		if (list->dev->subordinate)
>> +			res->flags = 0;
>> +
>> +		list = list->next;
>> +	}
>> +	free_failed_list(&head);
>> +
>> +	goto again;
>> +
>> +enable_and_dump:
>> +	/* Depth last, update the hardware. */
>> +	list_for_each_entry(bus, &pci_root_buses, node) {
>>  		pci_enable_bridges(bus);
>>  	}
> 
> Strictly speaking, you don't need these curly braces.

ok

Re: [PATCH 01/11] pci: add pci_bridge_release_unused_res and pci_bus_release_unused_bridge_res

[Yinghai Lu]

On 01/19/2010 01:26 PM, Alex Chiang wrote:
>> +static void __ref pci_bus_release_bridge_resources(struct pci_bus *bus,
>> +						   unsigned long type,
>> +						   enum release_type rel_type)
>> +{
>> +	struct pci_dev *dev;
>> +	bool is_leaf_bridge = true;
>> +
>> +	list_for_each_entry(dev, &bus->devices, bus_list) {
>> +		struct pci_bus *b = dev->subordinate;
>> +		if (!b)
>> +			continue;
>> +
>> +		switch (dev->class >> 8) {
>> +		case PCI_CLASS_BRIDGE_CARDBUS:
>> +			is_leaf_bridge = false;
>> +			break;
>> +
>> +		case PCI_CLASS_BRIDGE_PCI:
>> +		default:
>> +			is_leaf_bridge = false;
>> +			if (rel_type == whole_subtree)
>> +				pci_bus_release_bridge_resources(b, type,
>> +							 whole_subtree);
>> +			break;
>> +		}
>> +	}
> 
> I still don't understand this loop. Can't you write it like this:
> 
> 	list_for_each_entry(dev, &bus->devices, bus_list) {
> 		struct pci_bus *b = dev->subordinate;
> 		if (!b)
> 			continue;
> 
> 		is_leaf_bridge = false;
> 
> 		if ((dev->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS)
> 			continue;
> 
> 		if (rel_type == whole_subtree)
> 			pci_bus_release_bridge_resources(b, type,
> 						whole_subtree);
> 	}
> 
> I'm looking at that 'default' label in your switch() statement
> which causes us to always set is_leaf_bridge = false after 'b' is
> valid.

ok

[PATCH 00/11] pci: update pci bridge resources

[Yinghai Lu]

this patchset is trying to update pci bridge BAR when that BAR is big enough.

1. boot time:

BIOS separate IO range between several IOHs, and on some slots, BIOS assign
the resource to the bridge, but stop assigning resource to the device under
that bridge, because the device need big resource.

so patches (first 8) are trying to
a. pci assign unassign and record the failed device resource.
b. clear the BIOS assigned resource of the parent bridge of fail device
c. go back and call pci assign unsigned
d. if it still fail, will go up more bridges. and clear and try again.

v2: Jesse doesn't like it is in find_free_bus_resource...
    try to move out of pci_bus_size_bridges loop.
v3: add pci_setup_bridge calling after pci_bridge_release_not_used_res.
    only clear release those res for x86.
v4: Bjorn want to release use dev instead of bus.
v5: Kenji pointed out it will have problem with several level bridge.
    so let only handle leaf bridge.
v6: address Kenji's request (new pci_bus_release...). and change applying order
    move back release to pci_assign_unassigned_resource
v7: change functions name pci_bus_release_unused_bridge_res according to Jesse
v8: address Eric's concern, only overwrite leaf bridge resource that is not big
    enough need to do it in two steps, and first step recore the failed res,
    and don't touch bridge res that programmed by firmware. second step will
    try to release bridge resource that is too small at first.
v9: refresh to be applied after bjorn's patch, and remove trick about save
    size and restore resource second try.
v11:add pci=try=5, about more try to change more bridge
v12:not shrink pci bridge resource

2. hotplug:
BIOS separate IO range between several IOHs, and on some slots, BIOS assign
the resource to every bridge. (8M) but when insert one card that big resource,
the card can not get resource. because kernel will not touch the bridge
resource.

so patches (9-11) are trying to
a. assign resource to devices with that slot. and record fail devices
b. if there is some failed, will clear sepcifically io port of bridge, or mmio of bridge, or mmio pref of bridge.
c. try to assign the parent bridge of the slot.

v2: address Alex's concern about pci remove/rescan feature about
    pci_setup_bridge changes.
v3: Kenji pointed out that pci_config_slot need to be called before
    pci_bus_add_devices()
v4: move out pci_is_enabled checkout of pci_setup_bridge()
v5: change the applying sequence.
v6: change the functions name according to Jesse
v8: address Eric's concern, only overwrite leaf bridge resource that is not
     big enough
v9: refresh to be applied after bjorn's patch, and remove trick about save
    size and restore resource second try.
v10:alex found need to have export for pci_assign_unassigned_bridge_resources
v11: pass check_leaf with pci_bus_release_unused_bridge_res

patches (12-13)
will try to shrink, the pci hotplug related pcie port, so could save some for
others.

-v13: change resource_list to resource_list_x, to save size and flags aside,
      otherwise grandchild res will get confused with son's res as could be used

-v14: default it is disabled.  could use pci=try=2 to enable it.
-v15: seperate release_child_resources aside.

-v16: refresh according to new pci/linux-next of 2009_01_15
      change some name according to Jesse

Thanks

Yinghai