Added support function to find a PCI capability offset in the configuration data, needed for SATA support.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20149 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/drivers/PCI.h

@@ -147,6 +147,14 @@ struct pci_module_info {
 					);
 
 	void *			(*ram_address) (const void *physical_address_in_system_memory);
+
+	status_t		(*find_pci_capability) (
+						uchar	bus,
+						uchar	device,
+						uchar	function,
+						uchar	cap_id,
+						uchar	*offset
+					);
 };
 
 #define	B_PCI_MODULE_NAME		"bus_managers/pci/v1"
@@ -617,6 +625,7 @@ struct pci_module_info {
 #define PCI_cap_id_debugport    0x0a
 #define PCI_cap_id_cpci_rsrcctl 0x0b
 #define PCI_cap_id_hotplug      0x0c
+#define PCI_cap_id_sata         0x12      /* Serial ATA Capability */
 
 /** Power Management Control Status Register settings */
 #define PCI_pm_mask             0x03

src/add-ons/kernel/bus_managers/pci/pci.cpp

@@ -64,6 +64,64 @@ pci_write_config(uint8 virt_bus, uint8 device, uint8 function, uint8 offset, uin
 }
 
 
+status_t 
+pci_find_capability(uchar bus, uchar device, uchar function, uchar cap_id, uchar *offset)
+{
+	uint16 status;
+	uint8 header_type;
+	uint8 cap_ptr;
+	int i;
+
+	if (!offset) {
+		dprintf("find_pci_capability: ERROR %02x:%02x:%02x cap %02x offset NULL pointer\n", bus, device, function, cap_id);
+		return B_BAD_VALUE;
+	}
+
+	status = pci_read_config(bus, device, function, PCI_status, 2);
+	if (!(status & PCI_status_capabilities)) {
+		dprintf("find_pci_capability: ERROR %02x:%02x:%02x cap %02x not supported\n", bus, device, function, cap_id);
+		return B_ERROR;
+	}
+
+	header_type = pci_read_config(bus, device, function, PCI_header_type, 1);
+	switch (header_type & PCI_header_type_mask) {
+		case PCI_header_type_generic:
+		case PCI_header_type_PCI_to_PCI_bridge:
+			cap_ptr = pci_read_config(bus, device, function, PCI_capabilities_ptr, 1);
+			break;
+		case PCI_header_type_cardbus:
+			cap_ptr = pci_read_config(bus, device, function, PCI_capabilities_ptr_2, 1);
+			break;
+		default:
+			dprintf("find_pci_capability: ERROR %02x:%02x:%02x cap %02x unknown header type\n", bus, device, function, cap_id);
+			return B_ERROR;
+	}
+
+	cap_ptr &= ~3;
+	if (!cap_ptr) {
+		dprintf("find_pci_capability: ERROR %02x:%02x:%02x cap %02x empty list\n", bus, device, function, cap_id);
+		return B_NAME_NOT_FOUND;
+	}
+
+	for (i = 0; i < 48; i++) {
+		uint8 this_cap_id = pci_read_config(bus, device, function, cap_ptr, 1);
+		if (this_cap_id == cap_id) {
+			*offset = cap_ptr;
+			return B_OK;
+		}
+
+		cap_ptr = pci_read_config(bus, device, function, cap_ptr + 1, 1);
+		cap_ptr &= ~3;
+
+		if (!cap_ptr)
+			return B_NAME_NOT_FOUND;
+	}
+
+	dprintf("find_pci_capability: ERROR %02x:%02x:%02x cap %02x circular list\n", bus, device, function, cap_id);
+	return B_ERROR;
+}
+
+
 // #pragma mark bus manager init/uninit
 
 status_t

src/add-ons/kernel/bus_managers/pci/pci_module.c

@@ -221,7 +221,8 @@ static struct pci_module_info sOldPCIModule = {
 	&pci_get_nth_pci_info,
 	&pci_read_config,
 	&pci_write_config,
-	&pci_ram_address
+	&pci_ram_address,
+	&pci_find_capability
 };
 
 static struct pci_root_info sPCIModule = {

src/add-ons/kernel/bus_managers/pci/pci_priv.h

@@ -41,7 +41,9 @@ extern pci_device_module_info gPCIDeviceModule;
 extern "C" {
 #endif
 
-void		*pci_ram_address(const void *physical_address_in_system_memory);
+void *		pci_ram_address(const void *physical_address_in_system_memory);
+
+status_t 	pci_find_capability(uchar bus, uchar device, uchar function, uchar cap_id, uchar *offset);
 
 status_t 	pci_io_init(void);
 uint8		pci_read_io_8(int mapped_io_addr);