Commit a1a1132b authored by Clemens Ladisch's avatar Clemens Ladisch
Browse files

firewire: add CSR PRIORITY_BUDGET support 



If supported by the OHCI controller, implement the PRIORITY_BUDGET
register, which is required for nodes that can use asynchronous
priority arbitration.

To allow the core to determine what features the lowlevel device
supports, add a new card driver callback.

Signed-off-by: default avatarClemens Ladisch <clemens@ladisch.de>
parent 27a2329f

drivers/firewire/core-transaction.c

+14 −0
Original line number Diff line number Diff line
@@ -1126,6 +1126,20 @@ static void handle_registers(struct fw_card *card, struct fw_request *request, 
			rcode = RCODE_TYPE_ERROR;

		break;



	case CSR_PRIORITY_BUDGET:

		if (!(card->driver->get_features(card) &

						FEATURE_PRIORITY_BUDGET))

			rcode = RCODE_ADDRESS_ERROR;

		else if (tcode == TCODE_READ_QUADLET_REQUEST)

			*data = cpu_to_be32(card->driver->

				read_csr_reg(card, CSR_PRIORITY_BUDGET));

		else if (tcode == TCODE_WRITE_QUADLET_REQUEST)

			card->driver->write_csr_reg(card, CSR_PRIORITY_BUDGET,

						    be32_to_cpu(*data));

		else

			rcode = RCODE_TYPE_ERROR;

		break;



	case CSR_BROADCAST_CHANNEL:

		if (tcode == TCODE_READ_QUADLET_REQUEST)

			*data = cpu_to_be32(card->broadcast_channel);

drivers/firewire/core.h

+4 −0
Original line number Diff line number Diff line
@@ -38,6 +38,8 @@ struct fw_packet; 
#define BROADCAST_CHANNEL_INITIAL	(1 << 31 | 31)

#define BROADCAST_CHANNEL_VALID		(1 << 30)



#define FEATURE_PRIORITY_BUDGET		0x01



struct fw_card_driver {

	/*

	 * Enable the given card with the given initial config rom.
@@ -78,6 +80,8 @@ struct fw_card_driver { 
	u32 (*read_csr_reg)(struct fw_card *card, int csr_offset);

	void (*write_csr_reg)(struct fw_card *card, int csr_offset, u32 value);



	unsigned int (*get_features)(struct fw_card *card);



	struct fw_iso_context *

	(*allocate_iso_context)(struct fw_card *card,

				int type, int channel, size_t header_size);

drivers/firewire/ohci.c

+27 −0
Original line number Diff line number Diff line
@@ -170,6 +170,7 @@ struct fw_ohci { 
	int generation;

	int request_generation;	/* for timestamping incoming requests */

	unsigned quirks;

	unsigned int pri_req_max;

	u32 bus_time;



	/*
@@ -1738,6 +1739,11 @@ static int ohci_enable(struct fw_card *card, 
	reg_write(ohci, OHCI1394_IsochronousCycleTimer, seconds << 25);

	ohci->bus_time = seconds & ~0x3f;



	/* Get implemented bits of the priority arbitration request counter. */

	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);

	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;

	reg_write(ohci, OHCI1394_FairnessControl, 0);



	ar_context_run(&ohci->ar_request_ctx);

	ar_context_run(&ohci->ar_response_ctx);
@@ -2028,6 +2034,10 @@ static u32 ohci_read_csr_reg(struct fw_card *card, int csr_offset) 
		value = reg_read(ohci, OHCI1394_ATRetries);

		return (value >> 4) & 0x0ffff00f;



	case CSR_PRIORITY_BUDGET:

		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |

			(ohci->pri_req_max << 8);



	default:

		WARN_ON(1);

		return 0;
@@ -2065,12 +2075,28 @@ static void ohci_write_csr_reg(struct fw_card *card, int csr_offset, u32 value) 
		flush_writes(ohci);

		break;



	case CSR_PRIORITY_BUDGET:

		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);

		flush_writes(ohci);

		break;



	default:

		WARN_ON(1);

		break;

	}

}



static unsigned int ohci_get_features(struct fw_card *card)

{

	struct fw_ohci *ohci = fw_ohci(card);

	unsigned int features = 0;



	if (ohci->pri_req_max != 0)

		features |= FEATURE_PRIORITY_BUDGET;



	return features;

}



static void copy_iso_headers(struct iso_context *ctx, void *p)

{

	int i = ctx->header_length;
@@ -2510,6 +2536,7 @@ static const struct fw_card_driver ohci_driver = { 
	.enable_phys_dma	= ohci_enable_phys_dma,

	.read_csr_reg		= ohci_read_csr_reg,

	.write_csr_reg		= ohci_write_csr_reg,

	.get_features		= ohci_get_features,



	.allocate_iso_context	= ohci_allocate_iso_context,

	.free_iso_context	= ohci_free_iso_context,

include/linux/firewire.h

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#define CSR_CYCLE_TIME			0x200

#define CSR_BUS_TIME			0x204

#define CSR_BUSY_TIMEOUT		0x210

#define CSR_PRIORITY_BUDGET		0x218

#define CSR_BUS_MANAGER_ID		0x21c

#define CSR_BANDWIDTH_AVAILABLE		0x220

#define CSR_CHANNELS_AVAILABLE		0x224