[PATCH 0/7] PCI : bridge resource reallocation patchset -- followup

[PATCH 0/7] PCI : bridge resource reallocation patchset -- followup

[Yinghai Lu]

e4afda7: PCI: only enable pci realloc when SRIOV bar is not assigned
fee4a1e: PCI: print out suggestion about using pci=realloc
83f0fb3: PCI: Make pci bridge reallocating enabled/disabled
3ede49c: PCI: Retry on type IORESOURCE_IO allocation.
6becd43: PCI: Skip reset cardbus assigned resource during pci bus rescan
51f1186: PCI: Fix cardbus bridge resources as optional size handling
aa85d79: PCI: Disable cardbus bridge MEM1 pref CTL

are left over after Jesse pickup more of them.
it will try to auto detect if need to use pci=realloc, and print out suggestion.

including fixing some pci carbus handling.

could get from

	git://git.kernel.org/pub/scm/linux/kernel/git/yinghai/linux-yinghai.git for-pci3

Thanks

Yinghai

 Documentation/kernel-parameters.txt |    8 ++-
 drivers/pci/pci.c                   |    4 +-
 drivers/pci/pci.h                   |    2 +-
 drivers/pci/setup-bus.c             |  159 +++++++++++++++++++++++++----------
 4 files changed, 125 insertions(+), 48 deletions(-)

[PATCH 1/7] PCI: Disable cardbus bridge MEM1 pref CTL

[Yinghai Lu]

Some BIOS enable both pref for MEM0 and MEM1.

but we assume MEM1 is non-pref...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 090217a..d5897c3 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -914,6 +914,14 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 	if (realloc_head)
 		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size, 0 /* dont care */);
 
+	/* MEM1 must not be pref mmio */
+	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
+		ctrl &= ~PCI_CB_BRIDGE_CTL_PREFETCH_MEM1;
+		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl);
+		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
+	}
+
 	/*
 	 * Check whether prefetchable memory is supported
 	 * by this bridge.
-- 
1.7.7

[PATCH 2/7] PCI: Fix cardbus bridge resources as optional size handling

[Yinghai Lu]

We should not set the requested size to -2.

that will confuse the resource list sorting with align when SIZEALIGN is used.

Change to STARTALIGN and pass align from start.

We are safe to do that just as we do that regular pci bridge.

In the long run, we should just treat cardbus like regular pci bridge.

Also fix when realloc is not passed, should keep the requested size.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   63 ++++++++++++++++++++++++++--------------------
 1 files changed, 36 insertions(+), 27 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index d5897c3..3b3932a 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -898,21 +898,30 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 {
 	struct pci_dev *bridge = bus->self;
 	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES];
+	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
 	u16 ctrl;
 
 	/*
 	 * Reserve some resources for CardBus.  We reserve
 	 * a fixed amount of bus space for CardBus bridges.
 	 */
-	b_res[0].start = 0;
-	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
-	if (realloc_head)
-		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size, 0 /* dont care */);
+	b_res[0].start = pci_cardbus_io_size;
+	b_res[0].end = b_res[0].start + pci_cardbus_io_size - 1;
+	b_res[0].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[0].end -= pci_cardbus_io_size;
+		add_to_list(realloc_head, bridge, b_res, pci_cardbus_io_size,
+				pci_cardbus_io_size);
+	}
 
-	b_res[1].start = 0;
-	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_SIZEALIGN;
-	if (realloc_head)
-		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size, 0 /* dont care */);
+	b_res[1].start = pci_cardbus_io_size;
+	b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1;
+	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[1].end -= pci_cardbus_io_size;
+		add_to_list(realloc_head, bridge, b_res+1, pci_cardbus_io_size,
+				 pci_cardbus_io_size);
+	}
 
 	/* MEM1 must not be pref mmio */
 	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
@@ -939,28 +948,28 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 	 * twice the size.
 	 */
 	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) {
-		b_res[2].start = 0;
-		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+2, pci_cardbus_mem_size, 0 /* dont care */);
+		b_res[2].start = pci_cardbus_mem_size;
+		b_res[2].end = b_res[2].start + pci_cardbus_mem_size - 1;
+		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH |
+				  IORESOURCE_STARTALIGN;
+		if (realloc_head) {
+			b_res[2].end -= pci_cardbus_mem_size;
+			add_to_list(realloc_head, bridge, b_res+2,
+				 pci_cardbus_mem_size, pci_cardbus_mem_size);
+		}
 
-		b_res[3].start = 0;
-		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+3, pci_cardbus_mem_size, 0 /* dont care */);
-	} else {
-		b_res[3].start = 0;
-		b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_SIZEALIGN;
-		if (realloc_head)
-			add_to_list(realloc_head, bridge, b_res+3, pci_cardbus_mem_size * 2, 0 /* dont care */);
+		/* reduce that to half */
+		b_res_3_size = pci_cardbus_mem_size;
 	}
 
-	/* set the size of the resource to zero, so that the resource does not
-	 * get assigned during required-resource allocation cycle but gets assigned
-	 * during the optional-resource allocation cycle.
- 	 */
-	b_res[0].start = b_res[1].start = b_res[2].start = b_res[3].start = 1;
-	b_res[0].end = b_res[1].end = b_res[2].end = b_res[3].end = 0;
+	b_res[3].start = pci_cardbus_mem_size;
+	b_res[3].end = b_res[3].start + b_res_3_size - 1;
+	b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
+	if (realloc_head) {
+		b_res[3].end -= b_res_3_size;
+		add_to_list(realloc_head, bridge, b_res+3, b_res_3_size,
+				 pci_cardbus_mem_size);
+	}
 }
 
 void __ref __pci_bus_size_bridges(struct pci_bus *bus,
-- 
1.7.7

[PATCH 3/7] PCI: Skip reset cardbus assigned resource during pci bus rescan

[Yinghai Lu]

otherwise when rescan is used for cardbus, assigned resource will get
cleared.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 3b3932a..2991a89 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -901,6 +901,8 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 	resource_size_t b_res_3_size = pci_cardbus_mem_size * 2;
 	u16 ctrl;
 
+	if (b_res[0].parent)
+		goto handle_b_res_1;
 	/*
 	 * Reserve some resources for CardBus.  We reserve
 	 * a fixed amount of bus space for CardBus bridges.
@@ -914,6 +916,9 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 				pci_cardbus_io_size);
 	}
 
+handle_b_res_1:
+	if (b_res[1].parent)
+		goto handle_b_res_2;
 	b_res[1].start = pci_cardbus_io_size;
 	b_res[1].end = b_res[1].start + pci_cardbus_io_size - 1;
 	b_res[1].flags |= IORESOURCE_IO | IORESOURCE_STARTALIGN;
@@ -923,6 +928,7 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 				 pci_cardbus_io_size);
 	}
 
+handle_b_res_2:
 	/* MEM1 must not be pref mmio */
 	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
 	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM1) {
@@ -942,6 +948,8 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl);
 	}
 
+	if (b_res[2].parent)
+		goto handle_b_res_3;
 	/*
 	 * If we have prefetchable memory support, allocate
 	 * two regions.  Otherwise, allocate one region of
@@ -962,6 +970,9 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 		b_res_3_size = pci_cardbus_mem_size;
 	}
 
+handle_b_res_3:
+	if (b_res[3].parent)
+		goto handle_done;
 	b_res[3].start = pci_cardbus_mem_size;
 	b_res[3].end = b_res[3].start + b_res_3_size - 1;
 	b_res[3].flags |= IORESOURCE_MEM | IORESOURCE_STARTALIGN;
@@ -970,6 +981,9 @@ static void pci_bus_size_cardbus(struct pci_bus *bus,
 		add_to_list(realloc_head, bridge, b_res+3, b_res_3_size,
 				 pci_cardbus_mem_size);
 	}
+
+handle_done:
+	;
 }
 
 void __ref __pci_bus_size_bridges(struct pci_bus *bus,
-- 
1.7.7

[PATCH 4/7] PCI: Retry on type IORESOURCE_IO allocation.

[Yinghai Lu]

During reenabling pci reallocating for pci bridge by clean the small size in
bridge and assign with requested + optional size for first several try,
Ram mention could have problem with one case
	https://bugzilla.kernel.org/show_bug.cgi?id=15960

After checking the booting log in
	https://lkml.org/lkml/2010/4/19/44
	[regression, bisected] Xonar DX invalid PCI I/O range since 977d17bb174

We should not stop too early for io ports.
	Apr 19 10:19:38 [kernel] pci 0000:04:00.0: BAR 7: can't assign io (size 0x4000)
	Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 8: assigned [mem 0x80400000-0x805fffff]
	Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 7: can't assign io (size 0x2000)
	Apr 19 10:19:38 [kernel] pci 0000:05:02.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:05:03.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:08:00.0: BAR 7: can't assign io (size 0x1000)
	Apr 19 10:19:38 [kernel] pci 0000:09:04.0: BAR 0: can't assign io (size 0x100)
and clear 00:1c.0 to retry again.

The patch remove the IORESOUCE_IO checking, and try one more time.
and we will have chance to get allocation for 00:1c.0 io port range because
from 0x4000 to 0x8000 could be used.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   12 +-----------
 1 files changed, 1 insertions(+), 11 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 2991a89..162edfb 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1292,7 +1292,6 @@ pci_assign_unassigned_resources(void)
 	struct pci_dev_resource *fail_res;
 	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM |
 				  IORESOURCE_PREFETCH;
-	unsigned long failed_type;
 	int pci_try_num = 1;
 
 	/* don't realloc if asked to do so */
@@ -1327,16 +1326,7 @@ again:
 	if (list_empty(&fail_head))
 		goto enable_and_dump;
 
-	failed_type = 0;
-	list_for_each_entry(fail_res, &fail_head, list)
-		failed_type |= fail_res->flags;
-
-	/*
-	 * 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)) {
+	if (tried_times >= pci_try_num) {
 		free_list(&fail_head);
 		goto enable_and_dump;
 	}
-- 
1.7.7

[PATCH 5/7] PCI: Make pci bridge reallocating enabled/disabled

[Yinghai Lu]

Let the user could enable and disable with pci=realloc=on or pci=realloc=off

Also
1. move variable and functions near the place they are used.
2. change macro to function
3. change related functions and variable to static and _init
4. update parameter description accordingly.

-v2: still honor pci=realloc, and treat it as pci=realloc=on
     also use enum instead of ...

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 Documentation/kernel-parameters.txt |    8 ++++++--
 drivers/pci/pci.c                   |    4 +++-
 drivers/pci/pci.h                   |    2 +-
 drivers/pci/setup-bus.c             |   33 ++++++++++++++++++++++++++-------
 4 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 033d4e6..e11e5dd 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2109,8 +2109,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 				the default.
 				off: Turn ECRC off
 				on: Turn ECRC on.
-		realloc		reallocate PCI resources if allocations done by BIOS
-				are erroneous.
+		realloc=	Enable/disable reallocating PCI bridge resources
+				if allocations done by BIOS are too small to fit
+				resources required by children devices.
+				off: Turn realloc off
+				on: Turn realloc on
+		realloc		same as realloc=on
 
 	pcie_aspm=	[PCIE] Forcibly enable or disable PCIe Active State Power
 			Management.
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 9c89447..09cb1f2 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3744,8 +3744,10 @@ static int __init pci_setup(char *str)
 				pci_no_msi();
 			} else if (!strcmp(str, "noaer")) {
 				pci_no_aer();
+			} else if (!strncmp(str, "realloc=", 8)) {
+				pci_realloc_get_opt(str + 8);
 			} else if (!strncmp(str, "realloc", 7)) {
-				pci_realloc();
+				pci_realloc_get_opt("on");
 			} else if (!strcmp(str, "nodomains")) {
 				pci_no_domains();
 			} else if (!strncmp(str, "cbiosize=", 9)) {
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index aaf7ff8..f862a5a 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -148,7 +148,7 @@ static inline void pci_no_msi(void) { }
 static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { }
 #endif
 
-extern void pci_realloc(void);
+void pci_realloc_get_opt(char *);
 
 static inline int pci_no_d1d2(struct pci_dev *dev)
 {
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 162edfb..22454c5 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -48,13 +48,6 @@ static void free_list(struct list_head *head)
 	}
 }
 
-int pci_realloc_enable = 0;
-#define pci_realloc_enabled() pci_realloc_enable
-void pci_realloc(void)
-{
-	pci_realloc_enable = 1;
-}
-
 /**
  * add_to_list() - add a new resource tracker to the list
  * @head:	Head of the list
@@ -1273,6 +1266,32 @@ static int __init pci_get_max_depth(void)
 	return depth;
 }
 
+/*
+ * -1: undefined, will auto detect later
+ *  0: disabled by user
+ *  1: enabled by user
+ *  2: enabled by auto detect
+ */
+enum enable_type {
+	enable_not_set = -1,
+	enable_no_user,
+	enable_no_detected,
+	enable_yes_user,
+	enable_yes_detected,
+};
+
+static enum enable_type pci_realloc_enable __initdata = enable_not_set;
+void __init pci_realloc_get_opt(char *str)
+{
+	if (!strncmp(str, "off", 3))
+		pci_realloc_enable = enable_no_user;
+	else if (!strncmp(str, "on", 2))
+		pci_realloc_enable = enable_yes_user;
+}
+static bool __init pci_realloc_enabled(void)
+{
+	return pci_realloc_enable >= enable_yes_user;
+}
 
 /*
  * first try will not touch pci bridge res
-- 
1.7.7

[PATCH 6/7] PCI: print out suggestion about using pci=realloc

[Yinghai Lu]

let user know they could try if pci=realloc could help.

Suggested-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Yinghai Lu <yinghai@kerne.org>
---
 drivers/pci/setup-bus.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 22454c5..9526038 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1346,6 +1346,9 @@ again:
 		goto enable_and_dump;
 
 	if (tried_times >= pci_try_num) {
+		if (pci_realloc_enable == enable_not_set)
+			printk(KERN_INFO "Some pci devices resources are not assigned, please try to boot with pci=realloc\n");
+
 		free_list(&fail_head);
 		goto enable_and_dump;
 	}
-- 
1.7.7

[PATCH 7/7] PCI: only enable pci realloc when SRIOV bar is not assigned

[Yinghai Lu]

If bios does not assign those BAR or wrong address, then kernel will
try to do pci realloc.

in that case, user still can use pci=realloc=off to override it.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/pci/setup-bus.c |   28 ++++++++++++++++++++++++++++
 1 files changed, 28 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 9526038..520f256 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1293,6 +1293,31 @@ static bool __init pci_realloc_enabled(void)
 	return pci_realloc_enable >= enable_yes_user;
 }
 
+static void __init pci_realloc_detect(void)
+{
+	struct pci_dev *dev = NULL;
+
+	if (pci_realloc_enable != enable_not_set)
+		return;
+
+#ifdef CONFIG_PCI_IOV
+	for_each_pci_dev(dev) {
+		int i;
+
+		for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) {
+			struct resource *r = &dev->resource[i];
+
+			/* Not assigned, or rejected by kernel */
+			if (r->flags && !r->start) {
+				pci_realloc_enable = enable_yes_detected;
+
+				return;
+			}
+		}
+	}
+#endif
+}
+
 /*
  * first try will not touch pci bridge res
  * second  and later try will clear small leaf bridge res
@@ -1314,6 +1339,7 @@ pci_assign_unassigned_resources(void)
 	int pci_try_num = 1;
 
 	/* don't realloc if asked to do so */
+	pci_realloc_detect();
 	if (pci_realloc_enabled()) {
 		int max_depth = pci_get_max_depth();
 
@@ -1348,6 +1374,8 @@ again:
 	if (tried_times >= pci_try_num) {
 		if (pci_realloc_enable == enable_not_set)
 			printk(KERN_INFO "Some pci devices resources are not assigned, please try to boot with pci=realloc\n");
+		else if (pci_realloc_enable == enable_yes_detected)
+			printk(KERN_INFO "Automatically enabled pci realloc, if you have problem, please try to boot with pci=realloc=off\n");
 
 		free_list(&fail_head);
 		goto enable_and_dump;
-- 
1.7.7