dde_kit: enable pci lookup by device_class

Instead of trying all PCI devices by a specific PCI driver, now the device or
the device class can be limited to the one actually supported by the specific
driver.

dde_ipxe/src/lib/dde_ipxe/nic.c

@@ -293,7 +293,12 @@ int dde_ipxe_nic_init(void)
 {
 	dde_kit_init();
 	dde_kit_timer_init(0, 0);
-	dde_kit_pci_init();
+	enum {
+		CLASS_MASK  = 0xff0000,
+		CLASS_NETWORK = PCI_BASE_CLASS_NETWORK << 16
+	};
+	dde_kit_pci_init(CLASS_NETWORK, CLASS_MASK);
+
 	dde_kit_lock_init(&ipxe_lock);
 
 	slab_init();

dde_oss/src/drivers/oss/driver.cc

@@ -30,14 +30,18 @@ class Driver
 {
 	private:
 
-		enum { MAX_DRIVER = 10 };
+		enum {
+			MAX_DRIVER = 10,
+			PCI_CLASS_MASK  = 0xff0000,
+			PCI_CLASS_MULTIMEDIA = 0x40000, /* class multimedia */
+		};
 
 		oss_driver *_drivers[MAX_DRIVER + 1]; /* registered drivers */
 
 		Driver()
 		{
 			Genode::memset(_drivers, 0, sizeof(oss_driver *) * (MAX_DRIVER + 1));
-			dde_kit_pci_init();
+			dde_kit_pci_init(PCI_CLASS_MULTIMEDIA, PCI_CLASS_MASK);
 		}
 
 		/**
@@ -81,19 +85,13 @@ class Driver
 		Pci::Device_capability _scan_pci(Pci::Device_capability const &prev,
 		                                 Pci::Connection &pci)
 		{
-			/* check for audio device class */
-			enum {
-				CLASS_MASK  = 0xff0000,
-				CLASS_MULTIMEDIA = 0x40000, /* class multimedia */
-			};
-
 			/*
 			 * Just test for multimedia class, since some devices (e.g., Intel
 			 * hda) do set the subclass to something different then audio (0x1).
 			 */
 
 			Pci::Device_capability cap;
-			cap = pci.next_device(prev, CLASS_MULTIMEDIA, CLASS_MASK);
+			cap = pci.next_device(prev, PCI_CLASS_MULTIMEDIA, PCI_CLASS_MASK);
 			if (prev.valid())
 				pci.release_device(prev);
 			return cap;

os/include/dde_kit/pci.h

@@ -137,8 +137,28 @@ int dde_kit_pci_next_device(int *bus, int *dev, int *fun);
 
 /**
  * Initialize PCI subsystem
+ *
+ * The PCI subsystem can be instructed to request solely a specific PCI device
+ * or a specific PCI subset (one class or multiple). The parameters are
+ * described by the parameters device_class and class_mask, which are used to
+ * filter PCI class codes as described by the pseudo code:
+ *
+ * for each 'pci_device' out of 'all_pci_devices' try
+ * {
+ *    bool nohit = (pci_device.class_code() ^ device_class) & class_mask
+ *    if (!nohit)
+ *      use 'pci_device' with this PCI subsystem
+ * }
+ *
+ * If no restriction to the PCI subsystem should be applied, use 0 for the
+ * device_class and class_mask.
+ *
+ * \param device_class filter applied with 'bitwise XOR' operand to the class
+ *                     code of each PCI device
+ * \param class_mask   filter applied with 'bitwise AND' operand to the result
+ *                     out of device_class and PCI class code of each device
  */
-void dde_kit_pci_init(void);
+void dde_kit_pci_init(unsigned device_class, unsigned class_mask);
 
 
 #endif /* _INCLUDE__DDE_KIT__PCI_H_ */

os/src/lib/dde_kit/pci.cc

@@ -31,9 +31,10 @@ extern "C" {
 static const bool verbose = false;
 
 
-static Dde_kit::Pci_tree *pci_tree()
+static Dde_kit::Pci_tree *pci_tree(unsigned device_class = 0,
+                                   unsigned class_mask = 0)
 {
-	static Dde_kit::Pci_tree _pci_tree;
+	static Dde_kit::Pci_tree _pci_tree(device_class, class_mask);
 
 	return &_pci_tree;
 }
@@ -141,10 +142,10 @@ extern "C" int dde_kit_pci_next_device(int *bus, int *dev, int *fun)
  ** Initialization **
  ********************/
 
-extern "C" void dde_kit_pci_init(void)
+extern "C" void dde_kit_pci_init(unsigned device_class, unsigned class_mask)
 {
 	try {
-		pci_tree();
+		pci_tree(device_class, class_mask);
 	} catch (...) {
 		PERR("PCI initialization failed");
 	}

os/src/lib/dde_kit/pci_tree.cc

@@ -49,24 +49,25 @@ void Pci_device::config_write(unsigned char address, uint32_t val,
  ** PCI bus **
  *************/
 
-Pci_tree::Pci_tree()
+Pci_tree::Pci_tree(unsigned device_class, unsigned class_mask)
 {
 	/*
 	 * Iterate through all accessible devices and populate virtual
 	 * PCI bus tree.
 	 */
-	Pci::Device_capability prev_device_cap,
-	                            device_cap = _pci_drv.first_device();
+	Pci::Device_capability prev_device_cap;
+	Pci::Device_capability device_cap = _pci_drv.first_device(device_class,
+	                                                          class_mask);
 
 	while (device_cap.valid()) {
 
-		Pci_device *device = new (env()->heap())
-		                     Pci_device(device_cap);
+		Pci_device *device = new (env()->heap()) Pci_device(device_cap);
 
 		_devices.insert(device);
 
 		prev_device_cap = device_cap;
-		device_cap = _pci_drv.next_device(prev_device_cap);
+		device_cap = _pci_drv.next_device(prev_device_cap, device_class,
+		                                  class_mask);
 	}
 
 	if (verbose)

os/src/lib/dde_kit/pci_tree.h

@@ -198,7 +198,7 @@ namespace Dde_kit {
 
 		public:
 
-			Pci_tree();
+			Pci_tree(unsigned device_class, unsigned class_mask);
 
 			uint32_t config_read(int bus, int dev, int fun, unsigned char address,
 			                     Pci::Device::Access_size size)

os/src/test/dde_kit/test.cc

@@ -478,7 +478,7 @@ static void test_pci()
 {
 	PDBG("=== starting PCI test ===");
 
-	dde_kit_pci_init();
+	dde_kit_pci_init(0, 0);
 
 	enum { BUS_MAX = 4, DEV_MAX = 8 };