firewire: Implement CSR cycle time and bus time registers.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-ohci.c

@@ -139,6 +139,7 @@ struct fw_ohci {
 	int node_id;
 	int generation;
 	int request_generation;
+	u32 bus_seconds;
 
 	/* Spinlock for accessing fw_ohci data.  Never call out of
 	 * this driver with this lock held. */
@@ -959,7 +960,7 @@ static void bus_reset_tasklet(unsigned long data)
 static irqreturn_t irq_handler(int irq, void *data)
 {
 	struct fw_ohci *ohci = data;
-	u32 event, iso_event;
+	u32 event, iso_event, cycle_time;
 	int i;
 
 	event = reg_read(ohci, OHCI1394_IntEventClear);
@@ -1002,6 +1003,12 @@ static irqreturn_t irq_handler(int irq, void *data)
 		iso_event &= ~(1 << i);
 	}
 
+	if (event & OHCI1394_cycle64Seconds) {
+		cycle_time = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
+		if ((cycle_time & 0x80000000) == 0)
+			ohci->bus_seconds++;
+	}
+
 	return IRQ_HANDLED;
 }
 
@@ -1213,6 +1220,19 @@ ohci_enable_phys_dma(struct fw_card *card, int node_id, int generation)
 	return retval;
 }
 
+static u64
+ohci_get_bus_time(struct fw_card *card)
+{
+	struct fw_ohci *ohci = fw_ohci(card);
+	u32 cycle_time;
+	u64 bus_time;
+
+	cycle_time = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
+	bus_time = ((u64) ohci->bus_seconds << 32) | cycle_time;
+
+	return bus_time;
+}
+
 static int handle_ir_bufferfill_packet(struct context *context,
 				       struct descriptor *d,
 				       struct descriptor *last)
@@ -1686,6 +1706,7 @@ static const struct fw_card_driver ohci_driver = {
 	.send_response		= ohci_send_response,
 	.cancel_packet		= ohci_cancel_packet,
 	.enable_phys_dma	= ohci_enable_phys_dma,
+	.get_bus_time		= ohci_get_bus_time,
 
 	.allocate_iso_context	= ohci_allocate_iso_context,
 	.free_iso_context	= ohci_free_iso_context,
@@ -1862,7 +1883,8 @@ pci_probe(struct pci_dev *dev, const struct pci_device_id *ent)
 		  OHCI1394_RQPkt | OHCI1394_RSPkt |
 		  OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
 		  OHCI1394_isochRx | OHCI1394_isochTx |
-		  OHCI1394_masterIntEnable);
+		  OHCI1394_masterIntEnable |
+		  OHCI1394_cycle64Seconds);
 
 	bus_options = reg_read(ohci, OHCI1394_BusOptions);
 	max_receive = (bus_options >> 12) & 0xf;

drivers/firewire/fw-transaction.c

@@ -752,10 +752,65 @@ handle_topology_map(struct fw_card *card, struct fw_request *request,
 }
 
 static struct fw_address_handler topology_map = {
-	.length			= 0x400,
+	.length			= 0x200,
 	.address_callback	= handle_topology_map,
 };
 
+const struct fw_address_region registers_region =
+	{ .start = 0xfffff0000000ull, .end = 0xfffff0000400ull, };
+
+static void
+handle_registers(struct fw_card *card, struct fw_request *request,
+		 int tcode, int destination, int source,
+		 int generation, int speed,
+		 unsigned long long offset,
+		 void *payload, size_t length, void *callback_data)
+{
+	int reg = offset - CSR_REGISTER_BASE;
+	unsigned long long bus_time;
+	__be32 *data = payload;
+
+	switch (reg) {
+	case CSR_CYCLE_TIME:
+	case CSR_BUS_TIME:
+		if (!TCODE_IS_READ_REQUEST(tcode) || length != 4) {
+			fw_send_response(card, request, RCODE_TYPE_ERROR);
+			break;
+		}
+
+		bus_time = card->driver->get_bus_time(card);
+		if (reg == CSR_CYCLE_TIME)
+			*data = cpu_to_be32(bus_time);
+		else
+			*data = cpu_to_be32(bus_time >> 25);
+		fw_send_response(card, request, RCODE_COMPLETE);
+		break;
+
+	case CSR_BUS_MANAGER_ID:
+	case CSR_BANDWIDTH_AVAILABLE:
+	case CSR_CHANNELS_AVAILABLE_HI:
+	case CSR_CHANNELS_AVAILABLE_LO:
+		/* FIXME: these are handled by the OHCI hardware and
+		 * the stack never sees these request. If we add
+		 * support for a new type of controller that doesn't
+		 * handle this in hardware we need to deal with these
+		 * transactions. */
+		BUG();
+		break;
+
+	case CSR_BUSY_TIMEOUT:
+		/* FIXME: Implement this. */
+	default:
+		fw_send_response(card, request, RCODE_ADDRESS_ERROR);
+		break;
+	}
+}
+
+static struct fw_address_handler registers = {
+	.length			= 0x400,
+	.address_callback	= handle_registers,
+};
+
 MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
 MODULE_DESCRIPTION("Core IEEE1394 transaction logic");
 MODULE_LICENSE("GPL");
@@ -811,6 +866,10 @@ static int __init fw_core_init(void)
 					     &topology_map_region);
 	BUG_ON(retval < 0);
 
+	retval = fw_core_add_address_handler(&registers,
+					     &registers_region);
+	BUG_ON(retval < 0);
+
 	/* Add the vendor textual descriptor. */
 	retval = fw_core_add_descriptor(&vendor_id_descriptor);
 	BUG_ON(retval < 0);

drivers/firewire/fw-transaction.h

@@ -433,6 +433,8 @@ struct fw_card_driver {
 	int (*enable_phys_dma) (struct fw_card *card,
 				int node_id, int generation);
 
+	u64 (*get_bus_time) (struct fw_card *card);
+
 	struct fw_iso_context *
 	(*allocate_iso_context)(struct fw_card *card, int sync, int tags,
 				int type, size_t header_size);