device/pci: Declare pci_root_bus()
This is used a lot, cache the result so search
of domain from devicetree is only done once.
Improvement only applies when MAYBE_STATIC evaluates
to static.
Change-Id: If675abb632fe68acd59ba0bdfef854da3e0839a9
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34004
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/src/device/device_const.c b/src/device/device_const.c
index 6ce1d18..1853b4c 100644
--- a/src/device/device_const.c
+++ b/src/device/device_const.c
@@ -183,10 +183,24 @@
return find_dev_path(parent, &path);
}
-DEVTREE_CONST struct device *pcidev_path_on_root(pci_devfn_t devfn)
+DEVTREE_CONST struct bus *pci_root_bus(void)
{
DEVTREE_CONST struct device *pci_domain;
+ MAYBE_STATIC DEVTREE_CONST struct bus *pci_root = NULL;
+ if (pci_root)
+ return pci_root;
+
+ pci_domain = dev_find_path(NULL, DEVICE_PATH_DOMAIN);
+ if (!pci_domain)
+ return NULL;
+
+ pci_root = pci_domain->link_list;
+ return pci_root;
+}
+
+DEVTREE_CONST struct device *pcidev_path_on_root(pci_devfn_t devfn)
+{
/* Work around pcidev_path_behind() below failing
* due tue complicated devicetree with topology
* being manipulated on-the-fly.
@@ -194,11 +208,7 @@
if (CONFIG(NORTHBRIDGE_AMD_AMDFAM10))
return dev_find_slot(0, devfn);
- pci_domain = dev_find_path(NULL, DEVICE_PATH_DOMAIN);
- if (!pci_domain)
- return NULL;
-
- return pcidev_path_behind(pci_domain->link_list, devfn);
+ return pcidev_path_behind(pci_root_bus(), devfn);
}
DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn)
diff --git a/src/include/device/device.h b/src/include/device/device.h
index 8e9454c..a200de0 100644
--- a/src/include/device/device.h
+++ b/src/include/device/device.h
@@ -289,6 +289,7 @@
pci_devfn_t devfn);
DEVTREE_CONST struct device *pcidev_path_on_root(pci_devfn_t devfn);
DEVTREE_CONST struct device *pcidev_on_root(uint8_t dev, uint8_t fn);
+DEVTREE_CONST struct bus *pci_root_bus(void);
void scan_smbus(struct device *bus);
void scan_generic_bus(struct device *bus);