dm: pci: Support bridge device configuration correctly
Commit aec241d "dm: pci: Use the correct hose when configuring devices"
was an attempt to fix pci bridge device configuration, but unfortunately
that does not work 100%. In pciauto_config_devices(), the fix tried to
call pciauto_config_device() with a ctlr_hose which is supposed to be
the root controller hose, however when walking through a pci topology
with 2 or more pci bridges this logic simply fails.
The call chain is: pciauto_config_devices()->pciauto_config_device()
->dm_pci_hose_probe_bus(). Here the call to dm_pci_hose_probe_bus()
does not make any sense as the given hose is not the bridge device's
hose, instead it is either the root controller's hose (case#1: if it
is the 2nd pci bridge), or the bridge's parent bridge's hose (case#2:
if it is the 3rd pci bridge). In both cases the logic is wrong.
For example, for failing case#1 if the bridge device to config has the
same devfn as one of the devices under the root controller, the call
to pci_bus_find_devfn() will return the udevice of that pci device
under the root controller as the bus, but this is wrong as the udevice
is not a bus which does not contain all the necessary bits associated
with the udevice which causes further failures.
To correctly support pci bridge device configuration, we should still
call pciauto_config_device() with the pci bridge's hose directly.
In order to access valid pci region information, we need to refer to
the root controller simply by a call to pci_bus_to_hose(0) and get the
region information there in the pciauto_prescan_setup_bridge(),
pciauto_postscan_setup_bridge() and pciauto_config_device().
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
index ef6dc4f..a7af8cb 100644
--- a/drivers/pci/pci_auto.c
+++ b/drivers/pci/pci_auto.c
@@ -213,11 +213,24 @@
void pciauto_prescan_setup_bridge(struct pci_controller *hose,
pci_dev_t dev, int sub_bus)
{
- struct pci_region *pci_mem = hose->pci_mem;
- struct pci_region *pci_prefetch = hose->pci_prefetch;
- struct pci_region *pci_io = hose->pci_io;
+ struct pci_region *pci_mem;
+ struct pci_region *pci_prefetch;
+ struct pci_region *pci_io;
u16 cmdstat, prefechable_64;
+#ifdef CONFIG_DM_PCI
+ /* The root controller has the region information */
+ struct pci_controller *ctlr_hose = pci_bus_to_hose(0);
+
+ pci_mem = ctlr_hose->pci_mem;
+ pci_prefetch = ctlr_hose->pci_prefetch;
+ pci_io = ctlr_hose->pci_io;
+#else
+ pci_mem = hose->pci_mem;
+ pci_prefetch = hose->pci_prefetch;
+ pci_io = hose->pci_io;
+#endif
+
pci_hose_read_config_word(hose, dev, PCI_COMMAND, &cmdstat);
pci_hose_read_config_word(hose, dev, PCI_PREF_MEMORY_BASE,
&prefechable_64);
@@ -295,9 +308,22 @@
void pciauto_postscan_setup_bridge(struct pci_controller *hose,
pci_dev_t dev, int sub_bus)
{
- struct pci_region *pci_mem = hose->pci_mem;
- struct pci_region *pci_prefetch = hose->pci_prefetch;
- struct pci_region *pci_io = hose->pci_io;
+ struct pci_region *pci_mem;
+ struct pci_region *pci_prefetch;
+ struct pci_region *pci_io;
+
+#ifdef CONFIG_DM_PCI
+ /* The root controller has the region information */
+ struct pci_controller *ctlr_hose = pci_bus_to_hose(0);
+
+ pci_mem = ctlr_hose->pci_mem;
+ pci_prefetch = ctlr_hose->pci_prefetch;
+ pci_io = ctlr_hose->pci_io;
+#else
+ pci_mem = hose->pci_mem;
+ pci_prefetch = hose->pci_prefetch;
+ pci_io = hose->pci_io;
+#endif
/* Configure bus number registers */
#ifdef CONFIG_DM_PCI
@@ -425,10 +451,26 @@
*/
int pciauto_config_device(struct pci_controller *hose, pci_dev_t dev)
{
+ struct pci_region *pci_mem;
+ struct pci_region *pci_prefetch;
+ struct pci_region *pci_io;
unsigned int sub_bus = PCI_BUS(dev);
unsigned short class;
int n;
+#ifdef CONFIG_DM_PCI
+ /* The root controller has the region information */
+ struct pci_controller *ctlr_hose = pci_bus_to_hose(0);
+
+ pci_mem = ctlr_hose->pci_mem;
+ pci_prefetch = ctlr_hose->pci_prefetch;
+ pci_io = ctlr_hose->pci_io;
+#else
+ pci_mem = hose->pci_mem;
+ pci_prefetch = hose->pci_prefetch;
+ pci_io = hose->pci_io;
+#endif
+
pci_hose_read_config_word(hose, dev, PCI_CLASS_DEVICE, &class);
switch (class) {
@@ -436,8 +478,8 @@
DEBUGF("PCI Autoconfig: Found P2P bridge, device %d\n",
PCI_DEV(dev));
- pciauto_setup_device(hose, dev, 2, hose->pci_mem,
- hose->pci_prefetch, hose->pci_io);
+ pciauto_setup_device(hose, dev, 2, pci_mem,
+ pci_prefetch, pci_io);
#ifdef CONFIG_DM_PCI
n = dm_pci_hose_probe_bus(hose, dev);
@@ -467,8 +509,8 @@
* just do a minimal setup of the bridge,
* let the OS take care of the rest
*/
- pciauto_setup_device(hose, dev, 0, hose->pci_mem,
- hose->pci_prefetch, hose->pci_io);
+ pciauto_setup_device(hose, dev, 0, pci_mem,
+ pci_prefetch, pci_io);
DEBUGF("PCI Autoconfig: Found P2CardBus bridge, device %d\n",
PCI_DEV(dev));
@@ -502,8 +544,8 @@
DEBUGF("PCI AutoConfig: Found PowerPC device\n");
default:
- pciauto_setup_device(hose, dev, 6, hose->pci_mem,
- hose->pci_prefetch, hose->pci_io);
+ pciauto_setup_device(hose, dev, 6, pci_mem,
+ pci_prefetch, pci_io);
break;
}