ieee1394_core.c

Ieee1394驱动实现

/*
 * IEEE 1394 for Linux
 *
 * Core support: hpsb_packet management, packet handling and forwarding to
 *               highlevel or lowlevel code
 *
 * Copyright (C) 1999, 2000 Andreas E. Bombe
 *                     2002 Manfred Weihs <[e-mail]>
 *
 * This code is licensed under the GPL.  See the file COPYING in the root
 * directory of the kernel sources for details.
 *
 *
 * Contributions:
 *
 * Manfred Weihs <[e-mail]>
 *        loopback functionality in hpsb_send_packet
 *        allow highlevel drivers to disable automatic response generation
 *              and to generate responses themselves (deferred)
 *
 */

#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/bitops.h>
#include <linux/kdev_t.h>
#include <linux/suspend.h>
#include <linux/kthread.h>
#include <linux/preempt.h>
#include <linux/time.h>

#include <asm/system.h>
#include <asm/byteorder.h>

#include "ieee1394_types.h"
#include "ieee1394.h"
#include "hosts.h"
#include "ieee1394_core.h"
#include "highlevel.h"
#include "ieee1394_transactions.h"
#include "csr.h"
#include "nodemgr.h"
#include "dma.h"
#include "iso.h"
#include "config_roms.h"

/*
 * Disable the nodemgr detection and config rom reading functionality.
 */
static int disable_nodemgr;
module_param(disable_nodemgr, int, 0444);
MODULE_PARM_DESC(disable_nodemgr, "Disable nodemgr functionality.");

/* Disable Isochronous Resource Manager functionality */
int hpsb_disable_irm = 0;
module_param_named(disable_irm, hpsb_disable_irm, bool, 0444);
MODULE_PARM_DESC(disable_irm,
		 "Disable Isochronous Resource Manager functionality.");

/* We are GPL, so treat us special */
MODULE_LICENSE("GPL");

/* Some globals used */
const char *hpsb_speedto_str[] = { "S100", "S200", "S400", "S800", "S1600", "S3200" };
struct class *hpsb_protocol_class;

#ifdef CONFIG_IEEE1394_VERBOSEDEBUG
static void dump_packet(const char *text, quadlet_t *data, int size, int speed)
{
	int i;

	size /= 4;
	size = (size > 4 ? 4 : size);

	printk(KERN_DEBUG "ieee1394: %s", text);
	if (speed > -1 && speed < 6)
		printk(" at %s", hpsb_speedto_str[speed]);
	printk(":");
	for (i = 0; i < size; i++)
		printk(" %08x", data[i]);
	printk("\n");
}
#else
#define dump_packet(a,b,c,d) do {} while (0)
#endif

static void abort_requests(struct hpsb_host *host);
static void queue_packet_complete(struct hpsb_packet *packet);


/**
 * hpsb_set_packet_complete_task - set task that runs when a packet completes
 * @packet: the packet whose completion we want the task added to
 * @routine: function to call
 * @data: data (if any) to pass to the above function
 *
 * Set the task that runs when a packet completes. You cannot call this more
 * than once on a single packet before it is sent.
 *
 * Typically, the complete @routine is responsible to call hpsb_free_packet().
 */
void hpsb_set_packet_complete_task(struct hpsb_packet *packet,
				   void (*routine)(void *), void *data)
{
	WARN_ON(packet->complete_routine != NULL);
	packet->complete_routine = routine;
	packet->complete_data = data;
	return;
}

/**
 * hpsb_alloc_packet - allocate new packet structure
 * @data_size: size of the data block to be allocated, in bytes
 *
 * This function allocates, initializes and returns a new &struct hpsb_packet.
 * It can be used in interrupt context.  A header block is always included and
 * initialized with zeros.  Its size is big enough to contain all possible 1394
 * headers.  The data block is only allocated if @data_size is not zero.
 *
 * For packets for which responses will be received the @data_size has to be big
 * enough to contain the response's data block since no further allocation
 * occurs at response matching time.
 *
 * The packet's generation value will be set to the current generation number
 * for ease of use.  Remember to overwrite it with your own recorded generation
 * number if you can not be sure that your code will not race with a bus reset.
 *
 * Return value: A pointer to a &struct hpsb_packet or NULL on allocation
 * failure.
 */
struct hpsb_packet *hpsb_alloc_packet(size_t data_size)
{
	struct hpsb_packet *packet;

	data_size = ((data_size + 3) & ~3);

	packet = kzalloc(sizeof(*packet) + data_size, GFP_ATOMIC);
	if (!packet)
		return NULL;

	packet->state = hpsb_unused;
	packet->generation = -1;
	INIT_LIST_HEAD(&packet->driver_list);
	INIT_LIST_HEAD(&packet->queue);
	atomic_set(&packet->refcnt, 1);

	if (data_size) {
		packet->data = packet->embedded_data;
		packet->allocated_data_size = data_size;
	}
	return packet;
}

/**
 * hpsb_free_packet - free packet and data associated with it
 * @packet: packet to free (is NULL safe)
 *
 * Frees @packet->data only if it was allocated through hpsb_alloc_packet().
 */
void hpsb_free_packet(struct hpsb_packet *packet)
{
	if (packet && atomic_dec_and_test(&packet->refcnt)) {
		BUG_ON(!list_empty(&packet->driver_list) ||
		       !list_empty(&packet->queue));
		kfree(packet);
	}
}

/**
 * hpsb_reset_bus - initiate bus reset on the given host
 * @host: host controller whose bus to reset
 * @type: one of enum reset_types
 *
 * Returns 1 if bus reset already in progress, 0 otherwise.
 */
int hpsb_reset_bus(struct hpsb_host *host, int type)
{
	if (!host->in_bus_reset) {
		host->driver->devctl(host, RESET_BUS, type);
		return 0;
	} else {
		return 1;
	}
}

/**
 * hpsb_read_cycle_timer - read cycle timer register and system time
 * @host: host whose isochronous cycle timer register is read
 * @cycle_timer: address of bitfield to return the register contents
 * @local_time: address to return the system time
 *
 * The format of * @cycle_timer, is described in OHCI 1.1 clause 5.13. This
 * format is also read from non-OHCI controllers. * @local_time contains the
 * system time in microseconds since the Epoch, read at the moment when the
 * cycle timer was read.
 *
 * Return value: 0 for success or error number otherwise.
 */
int hpsb_read_cycle_timer(struct hpsb_host *host, u32 *cycle_timer,
			  u64 *local_time)
{
	int ctr;
	struct timeval tv;
	unsigned long flags;

	if (!host || !cycle_timer || !local_time)
		return -EINVAL;

	preempt_disable();
	local_irq_save(flags);

	ctr = host->driver->devctl(host, GET_CYCLE_COUNTER, 0);
	if (ctr)
		do_gettimeofday(&tv);

	local_irq_restore(flags);
	preempt_enable();

	if (!ctr)
		return -EIO;
	*cycle_timer = ctr;
	*local_time = tv.tv_sec * 1000000ULL + tv.tv_usec;
	return 0;
}

/**
 * hpsb_bus_reset - notify a bus reset to the core
 *
 * For host driver module usage.  Safe to use in interrupt context, although
 * quite complex; so you may want to run it in the bottom rather than top half.
 *
 * Returns 1 if bus reset already in progress, 0 otherwise.
 */
int hpsb_bus_reset(struct hpsb_host *host)
{
	if (host->in_bus_reset) {
		HPSB_NOTICE("%s called while bus reset already in progress",
			    __FUNCTION__);
		return 1;
	}

	abort_requests(host);
	host->in_bus_reset = 1;
	host->irm_id = -1;
	host->is_irm = 0;
	host->busmgr_id = -1;
	host->is_busmgr = 0;
	host->is_cycmst = 0;
	host->node_count = 0;
	host->selfid_count = 0;

	return 0;
}


/*
 * Verify num_of_selfids SelfIDs and return number of nodes.  Return zero in
 * case verification failed.
 */
static int check_selfids(struct hpsb_host *host)
{
	int nodeid = -1;
	int rest_of_selfids = host->selfid_count;
	struct selfid *sid = (struct selfid *)host->topology_map;
	struct ext_selfid *esid;
	int esid_seq = 23;

	host->nodes_active = 0;

	while (rest_of_selfids--) {
		if (!sid->extended) {
			nodeid++;
			esid_seq = 0;

			if (sid->phy_id != nodeid) {
				HPSB_INFO("SelfIDs failed monotony check with "
					  "%d", sid->phy_id);
				return 0;
			}

			if (sid->link_active) {
				host->nodes_active++;
				if (sid->contender)
					host->irm_id = LOCAL_BUS | sid->phy_id;
			}
		} else {
			esid = (struct ext_selfid *)sid;

			if ((esid->phy_id != nodeid)
			    || (esid->seq_nr != esid_seq)) {
				HPSB_INFO("SelfIDs failed monotony check with "
					  "%d/%d", esid->phy_id, esid->seq_nr);
				return 0;
			}
			esid_seq++;
		}
		sid++;
	}

	esid = (struct ext_selfid *)(sid - 1);
	while (esid->extended) {
		if ((esid->porta == SELFID_PORT_PARENT) ||
		    (esid->portb == SELFID_PORT_PARENT) ||
		    (esid->portc == SELFID_PORT_PARENT) ||
		    (esid->portd == SELFID_PORT_PARENT) ||
		    (esid->porte == SELFID_PORT_PARENT) ||
		    (esid->portf == SELFID_PORT_PARENT) ||
		    (esid->portg == SELFID_PORT_PARENT) ||
		    (esid->porth == SELFID_PORT_PARENT)) {
			HPSB_INFO("SelfIDs failed root check on "
				  "extended SelfID");
			return 0;
		}
		esid--;
	}

	sid = (struct selfid *)esid;
	if ((sid->port0 == SELFID_PORT_PARENT) ||
	    (sid->port1 == SELFID_PORT_PARENT) ||
	    (sid->port2 == SELFID_PORT_PARENT)) {
		HPSB_INFO("SelfIDs failed root check");
		return 0;
	}

	host->node_count = nodeid + 1;
	return 1;
}

static void build_speed_map(struct hpsb_host *host, int nodecount)
{
	u8 cldcnt[nodecount];
	u8 *map = host->speed_map;
	u8 *speedcap = host->speed;
	struct selfid *sid;
	struct ext_selfid *esid;
	int i, j, n;

	for (i = 0; i < (nodecount * 64); i += 64) {
		for (j = 0; j < nodecount; j++) {
			map[i+j] = IEEE1394_SPEED_MAX;
		}
	}

	for (i = 0; i < nodecount; i++) {
		cldcnt[i] = 0;
	}

	/* find direct children count and speed */
	for (sid = (struct selfid *)&host->topology_map[host->selfid_count-1],
		     n = nodecount - 1;
	     (void *)sid >= (void *)host->topology_map; sid--) {
		if (sid->extended) {
			esid = (struct ext_selfid *)sid;

			if (esid->porta == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->portb == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->portc == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->portd == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->porte == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->portf == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->portg == SELFID_PORT_CHILD) cldcnt[n]++;
			if (esid->porth == SELFID_PORT_CHILD) cldcnt[n]++;
                } else {
			if (sid->port0 == SELFID_PORT_CHILD) cldcnt[n]++;
			if (sid->port1 == SELFID_PORT_CHILD) cldcnt[n]++;
			if (sid->port2 == SELFID_PORT_CHILD) cldcnt[n]++;

			speedcap[n] = sid->speed;
			n--;
		}
	}

	/* set self mapping */
	for (i = 0; i < nodecount; i++) {
		map[64*i + i] = speedcap[i];
	}

	/* fix up direct children count to total children count;
	 * also fix up speedcaps for sibling and parent communication */
	for (i = 1; i < nodecount; i++) {
		for (j = cldcnt[i], n = i - 1; j > 0; j--) {
			cldcnt[i] += cldcnt[n];
			speedcap[n] = min(speedcap[n], speedcap[i]);
			n -= cldcnt[n] + 1;
		}
	}

	for (n = 0; n < nodecount; n++) {
		for (i = n - cldcnt[n]; i <= n; i++) {
			for (j = 0; j < (n - cldcnt[n]); j++) {
				map[j*64 + i] = map[i*64 + j] =
					min(map[i*64 + j], speedcap[n]);
			}
			for (j = n + 1; j < nodecount; j++) {
				map[j*64 + i] = map[i*64 + j] =
					min(map[i*64 + j], speedcap[n]);
			}
		}
	}

#if SELFID_SPEED_UNKNOWN != IEEE1394_SPEED_MAX
	/* assume maximum speed for 1394b PHYs, nodemgr will correct it */
	for (n = 0; n < nodecount; n++)
		if (speedcap[n] == SELFID_SPEED_UNKNOWN)
			speedcap[n] = IEEE1394_SPEED_MAX;
#endif
}


/**
 * hpsb_selfid_received - hand over received selfid packet to the core
 *
 * For host driver module usage.  Safe to use in interrupt context.
 *
 * The host driver should have done a successful complement check (second
 * quadlet is complement of first) beforehand.
 */
void hpsb_selfid_received(struct hpsb_host *host, quadlet_t sid)
{
	if (host->in_bus_reset) {
		HPSB_VERBOSE("Including SelfID 0x%x", sid);
		host->topology_map[host->selfid_count++] = sid;
	} else {
		HPSB_NOTICE("Spurious SelfID packet (0x%08x) received from bus %d",
			    sid, NODEID_TO_BUS(host->node_id));
	}
}

/**
 * hpsb_selfid_complete - notify completion of SelfID stage to the core
 *
 * For host driver module usage.  Safe to use in interrupt context, although
 * quite complex; so you may want to run it in the bottom rather than top half.
 *
 * Notify completion of SelfID stage to the core and report new physical ID
 * and whether host is root now.
 */
void hpsb_selfid_complete(struct hpsb_host *host, int phyid, int isroot)
{
	if (!host->in_bus_reset)
		HPSB_NOTICE("SelfID completion called outside of bus reset!");

	host->node_id = LOCAL_BUS | phyid;
	host->is_root = isroot;

	if (!check_selfids(host)) {
		if (host->reset_retries++ < 20) {
			/* selfid stage did not complete without error */
			HPSB_NOTICE("Error in SelfID stage, resetting");
			host->in_bus_reset = 0;
			/* this should work from ohci1394 now... */
			hpsb_reset_bus(host, LONG_RESET);
			return;
		} else {