#include <linux/errno.h>
#include <linux/firewire-cdev.h>
#include <linux/idr.h>
+#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/mm.h>
#include <linux/time.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
+#include <linux/workqueue.h>
#include <asm/system.h>
#include <asm/uaccess.h>
u32 data[0];
};
+struct iso_resource {
+ struct client_resource resource;
+ struct client *client;
+ /* Schedule work and access todo only with client->lock held. */
+ struct delayed_work work;
+ enum {ISO_RES_ALLOC, ISO_RES_REALLOC, ISO_RES_DEALLOC,} todo;
+ int generation;
+ u64 channels;
+ s32 bandwidth;
+ struct iso_resource_event *e_alloc, *e_dealloc;
+};
+
+static void schedule_iso_resource(struct iso_resource *);
+static void release_iso_resource(struct client *, struct client_resource *);
+
/*
* dequeue_event() just kfree()'s the event, so the event has to be
* the first field in a struct XYZ_event.
struct fw_cdev_event_iso_interrupt interrupt;
};
+struct iso_resource_event {
+ struct event event;
+ struct fw_cdev_event_iso_resource resource;
+};
+
static inline void __user *u64_to_uptr(__u64 value)
{
return (void __user *)(unsigned long)value;
mutex_unlock(&device->client_list_mutex);
}
+static int schedule_reallocations(int id, void *p, void *data)
+{
+ struct client_resource *r = p;
+
+ if (r->release == release_iso_resource)
+ schedule_iso_resource(container_of(r,
+ struct iso_resource, resource));
+ return 0;
+}
+
static void queue_bus_reset_event(struct client *client)
{
struct bus_reset_event *e;
queue_event(client, &e->event,
&e->reset, sizeof(e->reset), NULL, 0);
+
+ spin_lock_irq(&client->lock);
+ idr_for_each(&client->resource_idr, schedule_reallocations, client);
+ spin_unlock_irq(&client->lock);
}
void fw_device_cdev_update(struct fw_device *device)
else
ret = idr_get_new(&client->resource_idr, resource,
&resource->handle);
- if (ret >= 0)
+ if (ret >= 0) {
client_get(client);
+ if (resource->release == release_iso_resource)
+ schedule_iso_resource(container_of(resource,
+ struct iso_resource, resource));
+ }
spin_unlock_irqrestore(&client->lock, flags);
if (ret == -EAGAIN)
return 0;
}
+static void iso_resource_work(struct work_struct *work)
+{
+ struct iso_resource_event *e;
+ struct iso_resource *r =
+ container_of(work, struct iso_resource, work.work);
+ struct client *client = r->client;
+ int generation, channel, bandwidth, todo;
+ bool skip, free, success;
+
+ spin_lock_irq(&client->lock);
+ generation = client->device->generation;
+ todo = r->todo;
+ /* Allow 1000ms grace period for other reallocations. */
+ if (todo == ISO_RES_ALLOC &&
+ time_is_after_jiffies(client->device->card->reset_jiffies + HZ)) {
+ if (schedule_delayed_work(&r->work, DIV_ROUND_UP(HZ, 3)))
+ client_get(client);
+ skip = true;
+ } else {
+ /* We could be called twice within the same generation. */
+ skip = todo == ISO_RES_REALLOC &&
+ r->generation == generation;
+ }
+ free = todo == ISO_RES_DEALLOC;
+ r->generation = generation;
+ spin_unlock_irq(&client->lock);
+
+ if (skip)
+ goto out;
+
+ bandwidth = r->bandwidth;
+
+ fw_iso_resource_manage(client->device->card, generation,
+ r->channels, &channel, &bandwidth,
+ todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC);
+ /*
+ * Is this generation outdated already? As long as this resource sticks
+ * in the idr, it will be scheduled again for a newer generation or at
+ * shutdown.
+ */
+ if (channel == -EAGAIN &&
+ (todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC))
+ goto out;
+
+ success = channel >= 0 || bandwidth > 0;
+
+ spin_lock_irq(&client->lock);
+ /*
+ * Transit from allocation to reallocation, except if the client
+ * requested deallocation in the meantime.
+ */
+ if (r->todo == ISO_RES_ALLOC)
+ r->todo = ISO_RES_REALLOC;
+ /*
+ * Allocation or reallocation failure? Pull this resource out of the
+ * idr and prepare for deletion, unless the client is shutting down.
+ */
+ if (r->todo == ISO_RES_REALLOC && !success &&
+ !client->in_shutdown &&
+ idr_find(&client->resource_idr, r->resource.handle)) {
+ idr_remove(&client->resource_idr, r->resource.handle);
+ client_put(client);
+ free = true;
+ }
+ spin_unlock_irq(&client->lock);
+
+ if (todo == ISO_RES_ALLOC && channel >= 0)
+ r->channels = 1ULL << (63 - channel);
+
+ if (todo == ISO_RES_REALLOC && success)
+ goto out;
+
+ if (todo == ISO_RES_ALLOC) {
+ e = r->e_alloc;
+ r->e_alloc = NULL;
+ } else {
+ e = r->e_dealloc;
+ r->e_dealloc = NULL;
+ }
+ e->resource.handle = r->resource.handle;
+ e->resource.channel = channel;
+ e->resource.bandwidth = bandwidth;
+
+ queue_event(client, &e->event,
+ &e->resource, sizeof(e->resource), NULL, 0);
+
+ if (free) {
+ cancel_delayed_work(&r->work);
+ kfree(r->e_alloc);
+ kfree(r->e_dealloc);
+ kfree(r);
+ }
+ out:
+ client_put(client);
+}
+
+static void schedule_iso_resource(struct iso_resource *r)
+{
+ if (schedule_delayed_work(&r->work, 0))
+ client_get(r->client);
+}
+
+static void release_iso_resource(struct client *client,
+ struct client_resource *resource)
+{
+ struct iso_resource *r =
+ container_of(resource, struct iso_resource, resource);
+
+ spin_lock_irq(&client->lock);
+ r->todo = ISO_RES_DEALLOC;
+ schedule_iso_resource(r);
+ spin_unlock_irq(&client->lock);
+}
+
+static int ioctl_allocate_iso_resource(struct client *client, void *buffer)
+{
+ struct fw_cdev_allocate_iso_resource *request = buffer;
+ struct iso_resource_event *e1, *e2;
+ struct iso_resource *r;
+ int ret;
+
+ if ((request->channels == 0 && request->bandwidth == 0) ||
+ request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL ||
+ request->bandwidth < 0)
+ return -EINVAL;
+
+ r = kmalloc(sizeof(*r), GFP_KERNEL);
+ e1 = kmalloc(sizeof(*e1), GFP_KERNEL);
+ e2 = kmalloc(sizeof(*e2), GFP_KERNEL);
+ if (r == NULL || e1 == NULL || e2 == NULL) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ INIT_DELAYED_WORK(&r->work, iso_resource_work);
+ r->client = client;
+ r->todo = ISO_RES_ALLOC;
+ r->generation = -1;
+ r->channels = request->channels;
+ r->bandwidth = request->bandwidth;
+ r->e_alloc = e1;
+ r->e_dealloc = e2;
+
+ e1->resource.closure = request->closure;
+ e1->resource.type = FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED;
+ e2->resource.closure = request->closure;
+ e2->resource.type = FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED;
+
+ r->resource.release = release_iso_resource;
+ ret = add_client_resource(client, &r->resource, GFP_KERNEL);
+ if (ret < 0)
+ goto fail;
+ request->handle = r->resource.handle;
+
+ return 0;
+ fail:
+ kfree(r);
+ kfree(e1);
+ kfree(e2);
+
+ return ret;
+}
+
+static int ioctl_deallocate_iso_resource(struct client *client, void *buffer)
+{
+ struct fw_cdev_deallocate *request = buffer;
+
+ return release_client_resource(client, request->handle,
+ release_iso_resource, NULL);
+}
+
static int (* const ioctl_handlers[])(struct client *client, void *buffer) = {
ioctl_get_info,
ioctl_send_request,
ioctl_start_iso,
ioctl_stop_iso,
ioctl_get_cycle_timer,
+ ioctl_allocate_iso_resource,
+ ioctl_deallocate_iso_resource,
};
static int dispatch_ioctl(struct client *client,
/*
- * Isochronous IO functionality
+ * Isochronous I/O functionality:
+ * - Isochronous DMA context management
+ * - Isochronous bus resource management (channels, bandwidth), client side
*
* Copyright (C) 2006 Kristian Hoegsberg <krh@bitplanet.net>
*
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
-#include <linux/kernel.h>
-#include <linux/module.h>
#include <linux/dma-mapping.h>
-#include <linux/vmalloc.h>
+#include <linux/errno.h>
+#include <linux/firewire-constants.h>
+#include <linux/kernel.h>
#include <linux/mm.h>
+#include <linux/spinlock.h>
+#include <linux/vmalloc.h>
-#include "fw-transaction.h"
#include "fw-topology.h"
-#include "fw-device.h"
+#include "fw-transaction.h"
+
+/*
+ * Isochronous DMA context management
+ */
int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
int page_count, enum dma_data_direction direction)
{
return ctx->card->driver->stop_iso(ctx);
}
+
+/*
+ * Isochronous bus resource management (channels, bandwidth), client side
+ */
+
+static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
+ int bandwidth, bool allocate)
+{
+ __be32 data[2];
+ int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0;
+
+ /*
+ * On a 1394a IRM with low contention, try < 1 is enough.
+ * On a 1394-1995 IRM, we need at least try < 2.
+ * Let's just do try < 5.
+ */
+ for (try = 0; try < 5; try++) {
+ new = allocate ? old - bandwidth : old + bandwidth;
+ if (new < 0 || new > BANDWIDTH_AVAILABLE_INITIAL)
+ break;
+
+ data[0] = cpu_to_be32(old);
+ data[1] = cpu_to_be32(new);
+ switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
+ irm_id, generation, SCODE_100,
+ CSR_REGISTER_BASE + CSR_BANDWIDTH_AVAILABLE,
+ data, sizeof(data))) {
+ case RCODE_GENERATION:
+ /* A generation change frees all bandwidth. */
+ return allocate ? -EAGAIN : bandwidth;
+
+ case RCODE_COMPLETE:
+ if (be32_to_cpup(data) == old)
+ return bandwidth;
+
+ old = be32_to_cpup(data);
+ /* Fall through. */
+ }
+ }
+
+ return -EIO;
+}
+
+static int manage_channel(struct fw_card *card, int irm_id, int generation,
+ __be32 channels_mask, u64 offset, bool allocate)
+{
+ __be32 data[2], c, old = allocate ? cpu_to_be32(~0) : 0;
+ int i, retry = 5;
+
+ for (i = 0; i < 32; i++) {
+ c = cpu_to_be32(1 << (31 - i));
+ if (!(channels_mask & c))
+ continue;
+
+ if (allocate == !(old & c))
+ continue;
+
+ data[0] = old;
+ data[1] = old ^ c;
+ switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
+ irm_id, generation, SCODE_100,
+ offset, data, sizeof(data))) {
+ case RCODE_GENERATION:
+ /* A generation change frees all channels. */
+ return allocate ? -EAGAIN : i;
+
+ case RCODE_COMPLETE:
+ if (data[0] == old)
+ return i;
+
+ old = data[0];
+
+ /* Is the IRM 1394a-2000 compliant? */
+ if ((data[0] & c) != (data[1] & c))
+ continue;
+
+ /* 1394-1995 IRM, fall through to retry. */
+ default:
+ if (retry--)
+ i--;
+ }
+ }
+
+ return -EIO;
+}
+
+static void deallocate_channel(struct fw_card *card, int irm_id,
+ int generation, int channel)
+{
+ __be32 mask;
+ u64 offset;
+
+ mask = channel < 32 ? cpu_to_be32(1 << (31 - channel)) :
+ cpu_to_be32(1 << (63 - channel));
+ offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI :
+ CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO;
+
+ manage_channel(card, irm_id, generation, mask, offset, false);
+}
+
+/**
+ * fw_iso_resource_manage - Allocate or deallocate a channel and/or bandwidth
+ *
+ * In parameters: card, generation, channels_mask, bandwidth, allocate
+ * Out parameters: channel, bandwidth
+ * This function blocks (sleeps) during communication with the IRM.
+ * Allocates or deallocates at most one channel out of channels_mask.
+ *
+ * Returns channel < 0 if no channel was allocated or deallocated.
+ * Returns bandwidth = 0 if no bandwidth was allocated or deallocated.
+ *
+ * If generation is stale, deallocations succeed but allocations fail with
+ * channel = -EAGAIN.
+ *
+ * If channel (de)allocation fails, bandwidth (de)allocation fails too.
+ * If bandwidth allocation fails, no channel will be allocated either.
+ * If bandwidth deallocation fails, channel deallocation may still have been
+ * successful.
+ */
+void fw_iso_resource_manage(struct fw_card *card, int generation,
+ u64 channels_mask, int *channel, int *bandwidth,
+ bool allocate)
+{
+ __be32 channels_hi = cpu_to_be32(channels_mask >> 32);
+ __be32 channels_lo = cpu_to_be32(channels_mask);
+ int irm_id, ret, c = -EINVAL;
+
+ spin_lock_irq(&card->lock);
+ irm_id = card->irm_node->node_id;
+ spin_unlock_irq(&card->lock);
+
+ if (channels_hi)
+ c = manage_channel(card, irm_id, generation, channels_hi,
+ CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI, allocate);
+ if (channels_lo && c < 0) {
+ c = manage_channel(card, irm_id, generation, channels_lo,
+ CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO, allocate);
+ if (c >= 0)
+ c += 32;
+ }
+ *channel = c;
+
+ if (channels_mask != 0 && c < 0)
+ *bandwidth = 0;
+
+ if (*bandwidth == 0)
+ return;
+
+ ret = manage_bandwidth(card, irm_id, generation, *bandwidth, allocate);
+ if (ret < 0)
+ *bandwidth = 0;
+
+ if (ret < 0 && c >= 0 && allocate) {
+ deallocate_channel(card, irm_id, generation, c);
+ *channel = ret;
+ }
+}
#define CSR_SPEED_MAP 0x2000
#define CSR_SPEED_MAP_END 0x3000
+#define BANDWIDTH_AVAILABLE_INITIAL 4915
#define BROADCAST_CHANNEL_INITIAL (1 << 31 | 31)
#define BROADCAST_CHANNEL_VALID (1 << 30)
int fw_iso_context_stop(struct fw_iso_context *ctx);
void fw_iso_context_destroy(struct fw_iso_context *ctx);
+void fw_iso_resource_manage(struct fw_card *card, int generation,
+ u64 channels_mask, int *channel, int *bandwidth, bool allocate);
+
struct fw_card_driver {
/*
* Enable the given card with the given initial config rom.
#include <linux/types.h>
#include <linux/firewire-constants.h>
-#define FW_CDEV_EVENT_BUS_RESET 0x00
-#define FW_CDEV_EVENT_RESPONSE 0x01
-#define FW_CDEV_EVENT_REQUEST 0x02
-#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03
+#define FW_CDEV_EVENT_BUS_RESET 0x00
+#define FW_CDEV_EVENT_RESPONSE 0x01
+#define FW_CDEV_EVENT_REQUEST 0x02
+#define FW_CDEV_EVENT_ISO_INTERRUPT 0x03
+#define FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED 0x04
+#define FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED 0x05
/**
* struct fw_cdev_event_common - Common part of all fw_cdev_event_ types
__u32 header[0];
};
+/**
+ * struct fw_cdev_event_iso_resource - Iso resources were allocated or freed
+ * @closure: See &fw_cdev_event_common;
+ * set by %FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE ioctl
+ * @type: %FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED or
+ * %FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED
+ * @handle: Reference by which an allocated resource can be deallocated
+ * @channel: Isochronous channel which was (de)allocated, if any
+ * @bandwidth: Bandwidth allocation units which were (de)allocated, if any
+ * @channels_available: Last known availability of channels
+ * @bandwidth_available: Last known availability of bandwidth
+ *
+ * An %FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED event is sent after an isochronous
+ * resource was allocated at the IRM. The client has to check @channel and
+ * @bandwidth for whether the allocation actually succeeded.
+ *
+ * @channel is <0 if no channel was allocated.
+ * @bandwidth is 0 if no bandwidth was allocated.
+ *
+ * An %FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED event is sent after an isochronous
+ * resource was deallocated at the IRM. It is also sent when automatic
+ * reallocation after a bus reset failed.
+ */
+struct fw_cdev_event_iso_resource {
+ __u64 closure;
+ __u32 type;
+ __u32 handle;
+ __s32 channel;
+ __s32 bandwidth;
+};
+
/**
* union fw_cdev_event - Convenience union of fw_cdev_event_ types
* @common: Valid for all types
* @response: Valid if @common.type == %FW_CDEV_EVENT_RESPONSE
* @request: Valid if @common.type == %FW_CDEV_EVENT_REQUEST
* @iso_interrupt: Valid if @common.type == %FW_CDEV_EVENT_ISO_INTERRUPT
+ * @iso_resource: Valid if @common.type ==
+ * %FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED or
+ * %FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED
*
* Convenience union for userspace use. Events could be read(2) into an
* appropriately aligned char buffer and then cast to this union for further
* not fit will be discarded so that the next read(2) will return a new event.
*/
union fw_cdev_event {
- struct fw_cdev_event_common common;
- struct fw_cdev_event_bus_reset bus_reset;
- struct fw_cdev_event_response response;
- struct fw_cdev_event_request request;
- struct fw_cdev_event_iso_interrupt iso_interrupt;
+ struct fw_cdev_event_common common;
+ struct fw_cdev_event_bus_reset bus_reset;
+ struct fw_cdev_event_response response;
+ struct fw_cdev_event_request request;
+ struct fw_cdev_event_iso_interrupt iso_interrupt;
+ struct fw_cdev_event_iso_resource iso_resource;
};
+/* available since kernel version 2.6.22 */
#define FW_CDEV_IOC_GET_INFO _IOWR('#', 0x00, struct fw_cdev_get_info)
#define FW_CDEV_IOC_SEND_REQUEST _IOW('#', 0x01, struct fw_cdev_send_request)
#define FW_CDEV_IOC_ALLOCATE _IOWR('#', 0x02, struct fw_cdev_allocate)
#define FW_CDEV_IOC_INITIATE_BUS_RESET _IOW('#', 0x05, struct fw_cdev_initiate_bus_reset)
#define FW_CDEV_IOC_ADD_DESCRIPTOR _IOWR('#', 0x06, struct fw_cdev_add_descriptor)
#define FW_CDEV_IOC_REMOVE_DESCRIPTOR _IOW('#', 0x07, struct fw_cdev_remove_descriptor)
-
#define FW_CDEV_IOC_CREATE_ISO_CONTEXT _IOWR('#', 0x08, struct fw_cdev_create_iso_context)
#define FW_CDEV_IOC_QUEUE_ISO _IOWR('#', 0x09, struct fw_cdev_queue_iso)
#define FW_CDEV_IOC_START_ISO _IOW('#', 0x0a, struct fw_cdev_start_iso)
#define FW_CDEV_IOC_STOP_ISO _IOW('#', 0x0b, struct fw_cdev_stop_iso)
+
+/* available since kernel version 2.6.24 */
#define FW_CDEV_IOC_GET_CYCLE_TIMER _IOR('#', 0x0c, struct fw_cdev_get_cycle_timer)
+/* available since kernel version 2.6.30 */
+#define FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE _IOWR('#', 0x0d, struct fw_cdev_allocate_iso_resource)
+#define FW_CDEV_IOC_DEALLOCATE_ISO_RESOURCE _IOW('#', 0x0e, struct fw_cdev_deallocate)
+
/* FW_CDEV_VERSION History
*
* 1 Feb 18, 2007: Initial version.
};
/**
- * struct fw_cdev_deallocate - Free an address range allocation
- * @handle: Handle to the address range, as returned by the kernel when the
- * range was allocated
+ * struct fw_cdev_deallocate - Free a CSR address range or isochronous resource
+ * @handle: Handle to the address range or iso resource, as returned by the
+ * kernel when the range or resource was allocated
*/
struct fw_cdev_deallocate {
__u32 handle;
__u32 cycle_timer;
};
+/**
+ * struct fw_cdev_allocate_iso_resource - Allocate a channel or bandwidth
+ * @closure: Passed back to userspace in correponding iso resource events
+ * @channels: Isochronous channels of which one is to be allocated
+ * @bandwidth: Isochronous bandwidth units to be allocated
+ * @handle: Handle to the allocation, written by the kernel
+ *
+ * The %FW_CDEV_IOC_ALLOCATE_ISO_RESOURCE ioctl initiates allocation of an
+ * isochronous channel and/or of isochronous bandwidth at the isochronous
+ * resource manager (IRM). Only one of the channels specified in @channels is
+ * allocated. An %FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED is sent after
+ * communication with the IRM, indicating success or failure in the event data.
+ * The kernel will automatically reallocate the resources after bus resets.
+ * Should a reallocation fail, an %FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED event
+ * will be sent. The kernel will also automatically deallocate the resources
+ * when the file descriptor is closed.
+ *
+ * @channels is a host-endian bitfield with the most significant bit
+ * representing channel 0 and the least significant bit representing channel 63:
+ * 1ULL << (63 - c)
+ *
+ * @bandwidth is expressed in bandwidth allocation units, i.e. the time to send
+ * one quadlet of data (payload or header data) at speed S1600.
+ */
+struct fw_cdev_allocate_iso_resource {
+ __u64 closure;
+ __u64 channels;
+ __u32 bandwidth;
+ __u32 handle;
+};
+
#endif /* _LINUX_FIREWIRE_CDEV_H */
projects / linux-platform-drivers-x86.git / commitdiff