diff options
Diffstat (limited to 'src/devices/root_device.c')
-rw-r--r-- | src/devices/root_device.c | 35 |
1 files changed, 27 insertions, 8 deletions
diff --git a/src/devices/root_device.c b/src/devices/root_device.c index 78a81608ad..301db1889d 100644 --- a/src/devices/root_device.c +++ b/src/devices/root_device.c @@ -61,17 +61,27 @@ void root_dev_set_resources(device_t root) } /** - * Walk through devices on the motherboard and scan for devices behind - * them. + * @brief Scan devices on static buses. + * + * The existence of devices on certain buses can be completely determined at + * compile time by the config file. Typical expamles are the 'PNP' devices + * on an legacy ISA/LPC bus. There is no need of probing of any kind, the + * only thing we have to do is to walk through the bus and enable or disable + * devices as indicated in the config file. + * + * This function is the default scan_bus() method for LPC bridges. + * * @param root Pointer to the device structure for the system root device * @param max Maximum bus number allowed in the system. * @return Largest bus number used. */ -unsigned int walk_static_devices(device_t bus, unsigned int max) +unsigned int scan_static_bus(device_t bus, unsigned int max) { device_t child; unsigned link; + printk_debug("%s entered\n", __FUNCTION__); + for (link = 0; link < bus->links; link++) { for (child = bus->link[link].children; child; child = child->sibling) { if (child->ops && child->ops->enable) { @@ -89,15 +99,18 @@ unsigned int walk_static_devices(device_t bus, unsigned int max) max = child->ops->scan_bus(child, max); } } + + printk_debug("%s done\n", __FUNCTION__); + return max; } /** * @brief Enable resources for children devices * - * @param dev the device whos childrens resources are to be enabled + * @param dev the device whos children's resources are to be enabled * - * This function is call by the enable_resource + * This function is call by the enable_resource() */ void enable_childrens_resources(device_t dev) { @@ -113,9 +126,13 @@ void enable_childrens_resources(device_t dev) /** * @brief Scan root bus for generic PCI systems * - * @param root the root device structure - * @param max the current bus number scanned so fat, usually 0x00 + * @param root The root device structure + * @param max The current bus number scanned so fat, usually 0x00 * + * This function is the default scan_bus() method of the dynamic root device. + * The bus heirachy is rooted at the host/northbridge. The northbridge of a + * generic PCI bus system is at Bus 0, Dev 0, Fun 0 so we scan the whole PCI + * buses from there. */ unsigned int root_dev_scan_pci_bus(device_t root, unsigned int max) { @@ -141,7 +158,9 @@ struct device_operations default_dev_ops_root = { }; /** - * This is the root of the device tree. A PCI tree always has + * @brief The root of dynamic device tree. + * + * This is the root of the dynamic device tree. A PCI tree always has * one bus, bus 0. Bus 0 contains devices and bridges. */ struct device dev_root = { |