mirror of https://github.com/hak5/openwrt.git
151 lines
5.0 KiB
Diff
151 lines
5.0 KiB
Diff
From 61cb343b4ac20d2d957811cd492fec770646dda8 Mon Sep 17 00:00:00 2001
|
|
From: Gabor Juhos <juhosg@openwrt.org>
|
|
Date: Wed, 3 Apr 2013 19:47:50 +0200
|
|
Subject: [PATCH 1/2] pci/of: remove weak annotation of
|
|
pcibios_get_phb_of_node
|
|
|
|
Due to the __weak annotation in the forward declaration
|
|
of the 'pcibios_get_phb_of_node' function GCC will emit
|
|
a weak symbol for this functions even if the actual
|
|
implementation does not use the weak attribute.
|
|
|
|
If an architecture tries to override the function
|
|
by providing its own implementation there will be
|
|
multiple weak symbols with the same name in the
|
|
object files. When the kernel is linked from the
|
|
object files the linking order determines which
|
|
implementation will be used in the final image.
|
|
|
|
On x86 and on powerpc the architecture specific
|
|
version gets used:
|
|
|
|
$ readelf -s arch/x86/kernel/built-in.o drivers/pci/built-in.o \
|
|
vmlinux.o | grep pcibios_get_phb_of_node
|
|
3338: 00029b80 86 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
1701: 00012710 77 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
52072: 0002a170 86 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
$
|
|
|
|
$ powerpc-openwrt-linux-uclibc-readelf -s arch/powerpc/kernel/built-in.o \
|
|
drivers/pci/built-in.o vmlinux.o | grep pcibios_get_phb_of_node
|
|
1001: 0000cbb8 12 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
1484: 0001471c 88 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
28652: 0000d6f8 12 FUNC WEAK DEFAULT 1 pcibios_get_phb_of_node
|
|
$
|
|
|
|
However on MIPS, the linker puts the default
|
|
implementation into the final image:
|
|
|
|
$ mipsel-openwrt-linux-readelf -s arch/mips/pci/built-in.o \
|
|
drivers/pci/built-in.o vmlinux.o | grep pcibios_get_phb_of_node
|
|
86: 0000046c 12 FUNC WEAK DEFAULT 2 pcibios_get_phb_of_node
|
|
1430: 00012e2c 104 FUNC WEAK DEFAULT 2 pcibios_get_phb_of_node
|
|
31898: 0017e4ec 104 FUNC WEAK DEFAULT 2 pcibios_get_phb_of_node
|
|
$
|
|
|
|
Rename the default implementation and remove the
|
|
__weak annotation of that. This ensures that there
|
|
will be no multiple weak symbols with the same name
|
|
in the object files. In order to keep the expected
|
|
behaviour, call the architecture specific function
|
|
if the weak symbol is resolved.
|
|
|
|
Also move the renamed function to the top instead
|
|
of adding a new forward declaration for that.
|
|
|
|
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
|
|
---
|
|
Notes:
|
|
|
|
Unfortunately I'm not a binutils/gcc expert, so
|
|
I don't know if this is the expected behaviour
|
|
of those or not.
|
|
|
|
Removing the __weak annotation from the forward
|
|
declaration of 'pcibios_get_phb_of_node' in
|
|
'include/linux/pci.h' also fixes the problem.
|
|
|
|
The microblaze architecture also provides its own
|
|
implementation. The behaviour of that is not tested
|
|
but I assume that the linker chooses the arch specific
|
|
implementation on that as well similarly to the
|
|
x86/powerpc.
|
|
|
|
The MIPS version is implemented in the followup
|
|
patch.
|
|
|
|
Removing the __weak annotation from the forward
|
|
declaration of 'pcibios_get_phb_of_node' in
|
|
'include/linux/pci.h' also fixes the problem.
|
|
|
|
-Gabor
|
|
---
|
|
drivers/pci/of.c | 41 +++++++++++++++++++++++------------------
|
|
1 file changed, 23 insertions(+), 18 deletions(-)
|
|
|
|
--- a/drivers/pci/of.c
|
|
+++ b/drivers/pci/of.c
|
|
@@ -15,10 +15,32 @@
|
|
#include <linux/of_pci.h>
|
|
#include "pci.h"
|
|
|
|
+static struct device_node *__pcibios_get_phb_of_node(struct pci_bus *bus)
|
|
+{
|
|
+ /* This should only be called for PHBs */
|
|
+ if (WARN_ON(bus->self || bus->parent))
|
|
+ return NULL;
|
|
+
|
|
+ if (pcibios_get_phb_of_node)
|
|
+ return pcibios_get_phb_of_node(bus);
|
|
+
|
|
+ /* Look for a node pointer in either the intermediary device we
|
|
+ * create above the root bus or it's own parent. Normally only
|
|
+ * the later is populated.
|
|
+ */
|
|
+ if (bus->bridge->of_node)
|
|
+ return of_node_get(bus->bridge->of_node);
|
|
+ if (bus->bridge->parent && bus->bridge->parent->of_node)
|
|
+ return of_node_get(bus->bridge->parent->of_node);
|
|
+
|
|
+ return NULL;
|
|
+}
|
|
+
|
|
void pci_set_of_node(struct pci_dev *dev)
|
|
{
|
|
if (!dev->bus->dev.of_node)
|
|
return;
|
|
+
|
|
dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
|
|
dev->devfn);
|
|
}
|
|
@@ -32,7 +54,7 @@ void pci_release_of_node(struct pci_dev
|
|
void pci_set_bus_of_node(struct pci_bus *bus)
|
|
{
|
|
if (bus->self == NULL)
|
|
- bus->dev.of_node = pcibios_get_phb_of_node(bus);
|
|
+ bus->dev.of_node = __pcibios_get_phb_of_node(bus);
|
|
else
|
|
bus->dev.of_node = of_node_get(bus->self->dev.of_node);
|
|
}
|
|
@@ -42,20 +64,3 @@ void pci_release_bus_of_node(struct pci_
|
|
of_node_put(bus->dev.of_node);
|
|
bus->dev.of_node = NULL;
|
|
}
|
|
-
|
|
-struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
|
|
-{
|
|
- /* This should only be called for PHBs */
|
|
- if (WARN_ON(bus->self || bus->parent))
|
|
- return NULL;
|
|
-
|
|
- /* Look for a node pointer in either the intermediary device we
|
|
- * create above the root bus or it's own parent. Normally only
|
|
- * the later is populated.
|
|
- */
|
|
- if (bus->bridge->of_node)
|
|
- return of_node_get(bus->bridge->of_node);
|
|
- if (bus->bridge->parent && bus->bridge->parent->of_node)
|
|
- return of_node_get(bus->bridge->parent->of_node);
|
|
- return NULL;
|
|
-}
|