kernel-fxtec-pro1x/drivers/firewire/fw-transaction.h
Stefan Richter 4817ed2402 firewire: prevent creation of multiple IR DMA contexts for the same channel
OHCI-1394 1.1 clause 10.4.3 says:  "If more than one IR DMA context
specifies receives for packets from the same isochronous channel, the
context destination for that channel's packets is undefined."

Any userspace client and in the future also kernelspace clients can
allocate IR DMA contexts for any channel.  We don't want them to
interfere with each other, hence it is preferable to return -EBUSY if
allocation of a second context for a channel is attempted.

Notes:
  - This limitation is OHCI-1394 specific, therefore its proper place of
    implementation is down in the low-level driver.

  - Since the <linux/firewire-cdev.h> ABI simply maps one userspace iso
    client context to one hardware iso context, this OHCI-1394
    limitation alas requires userspace to implement its own multiplexing
    of iso reception from the same channel and card to multiple clients
    when needed.

  - The limitation is independent of channel allocation at the IRM; the
    latter is really only important for the initiation of iso 
    transmission but not of iso reception.

  - We don't need to do the same for IT DMA because OHCI-1394 does not
    have any ties between IT contexts and channels.  Only the voluntary
    channel allocation protocol via the IRM, globally to the FireWire
    bus, can ensure proper isochronous transmit behaviour anyway.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-03-24 20:56:41 +01:00

433 lines
13 KiB
C

/*
* Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef __fw_transaction_h
#define __fw_transaction_h
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/firewire-constants.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/spinlock_types.h>
#include <linux/timer.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#define TCODE_IS_READ_REQUEST(tcode) (((tcode) & ~1) == 4)
#define TCODE_IS_BLOCK_PACKET(tcode) (((tcode) & 1) != 0)
#define TCODE_IS_REQUEST(tcode) (((tcode) & 2) == 0)
#define TCODE_IS_RESPONSE(tcode) (((tcode) & 2) != 0)
#define TCODE_HAS_REQUEST_DATA(tcode) (((tcode) & 12) != 4)
#define TCODE_HAS_RESPONSE_DATA(tcode) (((tcode) & 12) != 0)
#define LOCAL_BUS 0xffc0
#define SELFID_PORT_CHILD 0x3
#define SELFID_PORT_PARENT 0x2
#define SELFID_PORT_NCONN 0x1
#define SELFID_PORT_NONE 0x0
#define PHY_PACKET_CONFIG 0x0
#define PHY_PACKET_LINK_ON 0x1
#define PHY_PACKET_SELF_ID 0x2
/* Bit fields _within_ the PHY registers. */
#define PHY_LINK_ACTIVE 0x80
#define PHY_CONTENDER 0x40
#define PHY_BUS_RESET 0x40
#define PHY_BUS_SHORT_RESET 0x40
#define CSR_REGISTER_BASE 0xfffff0000000ULL
/* register offsets relative to CSR_REGISTER_BASE */
#define CSR_STATE_CLEAR 0x0
#define CSR_STATE_SET 0x4
#define CSR_NODE_IDS 0x8
#define CSR_RESET_START 0xc
#define CSR_SPLIT_TIMEOUT_HI 0x18
#define CSR_SPLIT_TIMEOUT_LO 0x1c
#define CSR_CYCLE_TIME 0x200
#define CSR_BUS_TIME 0x204
#define CSR_BUSY_TIMEOUT 0x210
#define CSR_BUS_MANAGER_ID 0x21c
#define CSR_BANDWIDTH_AVAILABLE 0x220
#define CSR_CHANNELS_AVAILABLE 0x224
#define CSR_CHANNELS_AVAILABLE_HI 0x224
#define CSR_CHANNELS_AVAILABLE_LO 0x228
#define CSR_BROADCAST_CHANNEL 0x234
#define CSR_CONFIG_ROM 0x400
#define CSR_CONFIG_ROM_END 0x800
#define CSR_FCP_COMMAND 0xB00
#define CSR_FCP_RESPONSE 0xD00
#define CSR_FCP_END 0xF00
#define CSR_TOPOLOGY_MAP 0x1000
#define CSR_TOPOLOGY_MAP_END 0x1400
#define CSR_SPEED_MAP 0x2000
#define CSR_SPEED_MAP_END 0x3000
#define BROADCAST_CHANNEL_INITIAL (1 << 31 | 31)
#define BROADCAST_CHANNEL_VALID (1 << 30)
#define fw_notify(s, args...) printk(KERN_NOTICE KBUILD_MODNAME ": " s, ## args)
#define fw_error(s, args...) printk(KERN_ERR KBUILD_MODNAME ": " s, ## args)
static inline void fw_memcpy_from_be32(void *_dst, void *_src, size_t size)
{
u32 *dst = _dst;
__be32 *src = _src;
int i;
for (i = 0; i < size / 4; i++)
dst[i] = be32_to_cpu(src[i]);
}
static inline void fw_memcpy_to_be32(void *_dst, void *_src, size_t size)
{
fw_memcpy_from_be32(_dst, _src, size);
}
struct fw_card;
struct fw_packet;
struct fw_node;
struct fw_request;
struct fw_descriptor {
struct list_head link;
size_t length;
u32 immediate;
u32 key;
const u32 *data;
};
int fw_core_add_descriptor(struct fw_descriptor *desc);
void fw_core_remove_descriptor(struct fw_descriptor *desc);
typedef void (*fw_packet_callback_t)(struct fw_packet *packet,
struct fw_card *card, int status);
typedef void (*fw_transaction_callback_t)(struct fw_card *card, int rcode,
void *data, size_t length,
void *callback_data);
/*
* Important note: The callback must guarantee that either fw_send_response()
* or kfree() is called on the @request.
*/
typedef void (*fw_address_callback_t)(struct fw_card *card,
struct fw_request *request,
int tcode, int destination, int source,
int generation, int speed,
unsigned long long offset,
void *data, size_t length,
void *callback_data);
struct fw_packet {
int speed;
int generation;
u32 header[4];
size_t header_length;
void *payload;
size_t payload_length;
dma_addr_t payload_bus;
u32 timestamp;
/*
* This callback is called when the packet transmission has
* completed; for successful transmission, the status code is
* the ack received from the destination, otherwise it's a
* negative errno: ENOMEM, ESTALE, ETIMEDOUT, ENODEV, EIO.
* The callback can be called from tasklet context and thus
* must never block.
*/
fw_packet_callback_t callback;
int ack;
struct list_head link;
void *driver_data;
};
struct fw_transaction {
int node_id; /* The generation is implied; it is always the current. */
int tlabel;
int timestamp;
struct list_head link;
struct fw_packet packet;
/*
* The data passed to the callback is valid only during the
* callback.
*/
fw_transaction_callback_t callback;
void *callback_data;
};
struct fw_address_handler {
u64 offset;
size_t length;
fw_address_callback_t address_callback;
void *callback_data;
struct list_head link;
};
struct fw_address_region {
u64 start;
u64 end;
};
extern const struct fw_address_region fw_high_memory_region;
int fw_core_add_address_handler(struct fw_address_handler *handler,
const struct fw_address_region *region);
void fw_core_remove_address_handler(struct fw_address_handler *handler);
void fw_fill_response(struct fw_packet *response, u32 *request_header,
int rcode, void *payload, size_t length);
void fw_send_response(struct fw_card *card,
struct fw_request *request, int rcode);
extern struct bus_type fw_bus_type;
struct fw_card {
const struct fw_card_driver *driver;
struct device *device;
struct kref kref;
struct completion done;
int node_id;
int generation;
int current_tlabel, tlabel_mask;
struct list_head transaction_list;
struct timer_list flush_timer;
unsigned long reset_jiffies;
unsigned long long guid;
unsigned max_receive;
int link_speed;
int config_rom_generation;
spinlock_t lock; /* Take this lock when handling the lists in
* this struct. */
struct fw_node *local_node;
struct fw_node *root_node;
struct fw_node *irm_node;
u8 color; /* must be u8 to match the definition in struct fw_node */
int gap_count;
bool beta_repeaters_present;
int index;
struct list_head link;
/* Work struct for BM duties. */
struct delayed_work work;
int bm_retries;
int bm_generation;
u32 broadcast_channel;
u32 topology_map[(CSR_TOPOLOGY_MAP_END - CSR_TOPOLOGY_MAP) / 4];
};
static inline struct fw_card *fw_card_get(struct fw_card *card)
{
kref_get(&card->kref);
return card;
}
void fw_card_release(struct kref *kref);
static inline void fw_card_put(struct fw_card *card)
{
kref_put(&card->kref, fw_card_release);
}
extern void fw_schedule_bm_work(struct fw_card *card, unsigned long delay);
/*
* Check whether new_generation is the immediate successor of old_generation.
* Take counter roll-over at 255 (as per to OHCI) into account.
*/
static inline bool is_next_generation(int new_generation, int old_generation)
{
return (new_generation & 0xff) == ((old_generation + 1) & 0xff);
}
/*
* The iso packet format allows for an immediate header/payload part
* stored in 'header' immediately after the packet info plus an
* indirect payload part that is pointer to by the 'payload' field.
* Applications can use one or the other or both to implement simple
* low-bandwidth streaming (e.g. audio) or more advanced
* scatter-gather streaming (e.g. assembling video frame automatically).
*/
struct fw_iso_packet {
u16 payload_length; /* Length of indirect payload. */
u32 interrupt : 1; /* Generate interrupt on this packet */
u32 skip : 1; /* Set to not send packet at all. */
u32 tag : 2;
u32 sy : 4;
u32 header_length : 8; /* Length of immediate header. */
u32 header[0];
};
#define FW_ISO_CONTEXT_TRANSMIT 0
#define FW_ISO_CONTEXT_RECEIVE 1
#define FW_ISO_CONTEXT_MATCH_TAG0 1
#define FW_ISO_CONTEXT_MATCH_TAG1 2
#define FW_ISO_CONTEXT_MATCH_TAG2 4
#define FW_ISO_CONTEXT_MATCH_TAG3 8
#define FW_ISO_CONTEXT_MATCH_ALL_TAGS 15
struct fw_iso_context;
typedef void (*fw_iso_callback_t)(struct fw_iso_context *context,
u32 cycle, size_t header_length,
void *header, void *data);
/*
* An iso buffer is just a set of pages mapped for DMA in the
* specified direction. Since the pages are to be used for DMA, they
* are not mapped into the kernel virtual address space. We store the
* DMA address in the page private. The helper function
* fw_iso_buffer_map() will map the pages into a given vma.
*/
struct fw_iso_buffer {
enum dma_data_direction direction;
struct page **pages;
int page_count;
};
struct fw_iso_context {
struct fw_card *card;
int type;
int channel;
int speed;
size_t header_size;
fw_iso_callback_t callback;
void *callback_data;
};
int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
int page_count, enum dma_data_direction direction);
int fw_iso_buffer_map(struct fw_iso_buffer *buffer, struct vm_area_struct *vma);
void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer, struct fw_card *card);
struct fw_iso_context *fw_iso_context_create(struct fw_card *card,
int type, int channel, int speed, size_t header_size,
fw_iso_callback_t callback, void *callback_data);
int fw_iso_context_queue(struct fw_iso_context *ctx,
struct fw_iso_packet *packet,
struct fw_iso_buffer *buffer,
unsigned long payload);
int fw_iso_context_start(struct fw_iso_context *ctx,
int cycle, int sync, int tags);
int fw_iso_context_stop(struct fw_iso_context *ctx);
void fw_iso_context_destroy(struct fw_iso_context *ctx);
struct fw_card_driver {
/*
* Enable the given card with the given initial config rom.
* This function is expected to activate the card, and either
* enable the PHY or set the link_on bit and initiate a bus
* reset.
*/
int (*enable)(struct fw_card *card, u32 *config_rom, size_t length);
int (*update_phy_reg)(struct fw_card *card, int address,
int clear_bits, int set_bits);
/*
* Update the config rom for an enabled card. This function
* should change the config rom that is presented on the bus
* an initiate a bus reset.
*/
int (*set_config_rom)(struct fw_card *card,
u32 *config_rom, size_t length);
void (*send_request)(struct fw_card *card, struct fw_packet *packet);
void (*send_response)(struct fw_card *card, struct fw_packet *packet);
/* Calling cancel is valid once a packet has been submitted. */
int (*cancel_packet)(struct fw_card *card, struct fw_packet *packet);
/*
* Allow the specified node ID to do direct DMA out and in of
* host memory. The card will disable this for all node when
* a bus reset happens, so driver need to reenable this after
* bus reset. Returns 0 on success, -ENODEV if the card
* doesn't support this, -ESTALE if the generation doesn't
* match.
*/
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 type, int channel, size_t header_size);
void (*free_iso_context)(struct fw_iso_context *ctx);
int (*start_iso)(struct fw_iso_context *ctx,
s32 cycle, u32 sync, u32 tags);
int (*queue_iso)(struct fw_iso_context *ctx,
struct fw_iso_packet *packet,
struct fw_iso_buffer *buffer,
unsigned long payload);
int (*stop_iso)(struct fw_iso_context *ctx);
};
int fw_core_initiate_bus_reset(struct fw_card *card, int short_reset);
void fw_send_request(struct fw_card *card, struct fw_transaction *t,
int tcode, int destination_id, int generation, int speed,
unsigned long long offset, void *data, size_t length,
fw_transaction_callback_t callback, void *callback_data);
int fw_cancel_transaction(struct fw_card *card,
struct fw_transaction *transaction);
void fw_flush_transactions(struct fw_card *card);
int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
int generation, int speed, unsigned long long offset,
void *data, size_t length);
void fw_send_phy_config(struct fw_card *card,
int node_id, int generation, int gap_count);
/*
* Called by the topology code to inform the device code of node
* activity; found, lost, or updated nodes.
*/
void fw_node_event(struct fw_card *card, struct fw_node *node, int event);
/* API used by card level drivers */
void fw_card_initialize(struct fw_card *card,
const struct fw_card_driver *driver, struct device *device);
int fw_card_add(struct fw_card *card,
u32 max_receive, u32 link_speed, u64 guid);
void fw_core_remove_card(struct fw_card *card);
void fw_core_handle_bus_reset(struct fw_card *card, int node_id,
int generation, int self_id_count, u32 *self_ids);
void fw_core_handle_request(struct fw_card *card, struct fw_packet *request);
void fw_core_handle_response(struct fw_card *card, struct fw_packet *packet);
#endif /* __fw_transaction_h */