/* * IEEE 1394 for Linux * * Transaction support. * * Copyright (C) 1999 Andreas E. Bombe * * This code is licensed under the GPL. See the file COPYING in the root * directory of the kernel sources for details. */ #include <linux/bitops.h> #include <linux/compiler.h> #include <linux/hardirq.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/sched.h> /* because linux/wait.h is broken if CONFIG_SMP=n */ #include <linux/wait.h> #include <asm/bug.h> #include <asm/errno.h> #include <asm/system.h> #include "ieee1394.h" #include "ieee1394_types.h" #include "hosts.h" #include "ieee1394_core.h" #include "ieee1394_transactions.h" #define PREP_ASYNC_HEAD_ADDRESS(tc) \ packet->tcode = tc; \ packet->header[0] = (packet->node_id << 16) | (packet->tlabel << 10) \ | (1 << 8) | (tc << 4); \ packet->header[1] = (packet->host->node_id << 16) | (addr >> 32); \ packet->header[2] = addr & 0xffffffff #ifndef HPSB_DEBUG_TLABELS static #endif DEFINE_SPINLOCK(hpsb_tlabel_lock); static DECLARE_WAIT_QUEUE_HEAD(tlabel_wq); static void fill_async_readquad(struct hpsb_packet *packet, u64 addr) { PREP_ASYNC_HEAD_ADDRESS(TCODE_READQ); packet->header_size = 12; packet->data_size = 0; packet->expect_response = 1; } static void fill_async_readblock(struct hpsb_packet *packet, u64 addr, int length) { PREP_ASYNC_HEAD_ADDRESS(TCODE_READB); packet->header[3] = length << 16; packet->header_size = 16; packet->data_size = 0; packet->expect_response = 1; } static void fill_async_writequad(struct hpsb_packet *packet, u64 addr, quadlet_t data) { PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEQ); packet->header[3] = data; packet->header_size = 16; packet->data_size = 0; packet->expect_response = 1; } static void fill_async_writeblock(struct hpsb_packet *packet, u64 addr, int length) { PREP_ASYNC_HEAD_ADDRESS(TCODE_WRITEB); packet->header[3] = length << 16; packet->header_size = 16; packet->expect_response = 1; packet->data_size = length + (length % 4 ? 4 - (length % 4) : 0); } static void fill_async_lock(struct hpsb_packet *packet, u64 addr, int extcode, int length) { PREP_ASYNC_HEAD_ADDRESS(TCODE_LOCK_REQUEST); packet->header[3] = (length << 16) | extcode; packet->header_size = 16; packet->data_size = length; packet->expect_response = 1; } static void fill_phy_packet(struct hpsb_packet *packet, quadlet_t data) { packet->header[0] = data; packet->header[1] = ~data; packet->header_size = 8; packet->data_size = 0; packet->expect_response = 0; packet->type = hpsb_raw; /* No CRC added */ packet->speed_code = IEEE1394_SPEED_100; /* Force speed to be 100Mbps */ } static void fill_async_stream_packet(struct hpsb_packet *packet, int length, int channel, int tag, int sync) { packet->header[0] = (length << 16) | (tag << 14) | (channel << 8) | (TCODE_STREAM_DATA << 4) | sync; packet->header_size = 4; packet->data_size = length; packet->type = hpsb_async; packet->tcode = TCODE_ISO_DATA; } /* same as hpsb_get_tlabel, except that it returns immediately */ static int hpsb_get_tlabel_atomic(struct hpsb_packet *packet) { unsigned long flags, *tp; u8 *next; int tlabel, n = NODEID_TO_NODE(packet->node_id); /* Broadcast transactions are complete once the request has been sent. * Use the same transaction label for all broadcast transactions. */ if (unlikely(n == ALL_NODES)) { packet->tlabel = 0; return 0; } tp = packet->host->tl_pool[n].map; next = &packet->host->next_tl[n]; spin_lock_irqsave(&hpsb_tlabel_lock, flags); tlabel = find_next_zero_bit(tp, 64, *next); if (tlabel > 63) tlabel = find_first_zero_bit(tp, 64); if (tlabel > 63) { spin_unlock_irqrestore(&hpsb_tlabel_lock, flags); return -EAGAIN; } __set_bit(tlabel, tp); *next = (tlabel + 1) & 63; spin_unlock_irqrestore(&hpsb_tlabel_lock, flags); packet->tlabel = tlabel; return 0; } /** * hpsb_get_tlabel - allocate a transaction label * @packet: the packet whose tlabel and tl_pool we set * * Every asynchronous transaction on the 1394 bus needs a transaction * label to match the response to the request. This label has to be * different from any other transaction label in an outstanding request to * the same node to make matching possible without ambiguity. * * There are 64 different tlabels, so an allocated tlabel has to be freed * with hpsb_free_tlabel() after the transaction is complete (unless it's * reused again for the same target node). * * Return value: Zero on success, otherwise non-zero. A non-zero return * generally means there are no available tlabels. If this is called out * of interrupt or atomic context, then it will sleep until can return a * tlabel or a signal is received. */ int hpsb_get_tlabel(struct hpsb_packet *packet) { if (irqs_disabled() || in_atomic()) return hpsb_get_tlabel_atomic(packet); /* NB: The macro wait_event_interruptible() is called with a condition * argument with side effect. This is only possible because the side * effect does not occur until the condition became true, and * wait_event_interruptible() won't evaluate the condition again after * that. */ return wait_event_interruptible(tlabel_wq, !hpsb_get_tlabel_atomic(packet)); } /** * hpsb_free_tlabel - free an allocated transaction label * @packet: packet whose tlabel and tl_pool needs to be cleared * * Frees the transaction label allocated with hpsb_get_tlabel(). The * tlabel has to be freed after the transaction is complete (i.e. response * was received for a split transaction or packet was sent for a unified * transaction). * * A tlabel must not be freed twice. */ void hpsb_free_tlabel(struct hpsb_packet *packet) { unsigned long flags, *tp; int tlabel, n = NODEID_TO_NODE(packet->node_id); if (unlikely(n == ALL_NODES)) return; tp = packet->host->tl_pool[n].map; tlabel = packet->tlabel; BUG_ON(tlabel > 63 || tlabel < 0); spin_lock_irqsave(&hpsb_tlabel_lock, flags); BUG_ON(!__test_and_clear_bit(tlabel, tp)); spin_unlock_irqrestore(&hpsb_tlabel_lock, flags); wake_up_interruptible(&tlabel_wq); } /** * hpsb_packet_success - Make sense of the ack and reply codes * * Make sense of the ack and reply codes and return more convenient error codes: * 0 = success. -%EBUSY = node is busy, try again. -%EAGAIN = error which can * probably resolved by retry. -%EREMOTEIO = node suffers from an internal * error. -%EACCES = this transaction is not allowed on requested address. * -%EINVAL = invalid address at node. */ int hpsb_packet_success(struct hpsb_packet *packet) { switch (packet->ack_code) { case ACK_PENDING: switch ((packet->header[1] >> 12) & 0xf) { case RCODE_COMPLETE: return 0; case RCODE_CONFLICT_ERROR: return -EAGAIN; case RCODE_DATA_ERROR: return -EREMOTEIO; case RCODE_TYPE_ERROR: return -EACCES; case RCODE_ADDRESS_ERROR: return -EINVAL; default: HPSB_ERR("received reserved rcode %d from node %d", (packet->header[1] >> 12) & 0xf, packet->node_id); return -EAGAIN; } case ACK_BUSY_X: case ACK_BUSY_A: case ACK_BUSY_B: return -EBUSY; case ACK_TYPE_ERROR: return -EACCES; case ACK_COMPLETE: if (packet->tcode == TCODE_WRITEQ || packet->tcode == TCODE_WRITEB) { return 0; } else { HPSB_ERR("impossible ack_complete from node %d " "(tcode %d)", packet->node_id, packet->tcode); return -EAGAIN; } case ACK_DATA_ERROR: if (packet->tcode == TCODE_WRITEB || packet->tcode == TCODE_LOCK_REQUEST) { return -EAGAIN; } else { HPSB_ERR("impossible ack_data_error from node %d " "(tcode %d)", packet->node_id, packet->tcode); return -EAGAIN; } case ACK_ADDRESS_ERROR: return -EINVAL; case ACK_TARDY: case ACK_CONFLICT_ERROR: case ACKX_NONE: case ACKX_SEND_ERROR: case ACKX_ABORTED: case ACKX_TIMEOUT: /* error while sending */ return -EAGAIN; default: HPSB_ERR("got invalid ack %d from node %d (tcode %d)", packet->ack_code, packet->node_id, packet->tcode); return -EAGAIN; } } struct hpsb_packet *hpsb_make_readpacket(struct hpsb_host *host, nodeid_t node, u64 addr, size_t length) { struct hpsb_packet *packet; if (length == 0) return NULL; packet = hpsb_alloc_packet(length); if (!packet) return NULL; packet->host = host; packet->node_id = node; if (hpsb_get_tlabel(packet)) { hpsb_free_packet(packet); return NULL; } if (length == 4) fill_async_readquad(packet, addr); else fill_async_readblock(packet, addr, length); return packet; } struct hpsb_packet *hpsb_make_writepacket(struct hpsb_host *host, nodeid_t node, u64 addr, quadlet_t * buffer, size_t length) { struct hpsb_packet *packet; if (length == 0) return NULL; packet = hpsb_alloc_packet(length); if (!packet) return NULL; if (length % 4) { /* zero padding bytes */ packet->data[length >> 2] = 0; } packet->host = host; packet->node_id = node; if (hpsb_get_tlabel(packet)) { hpsb_free_packet(packet); return NULL; } if (length == 4) { fill_async_writequad(packet, addr, buffer ? *buffer : 0); } else { fill_async_writeblock(packet, addr, length); if (buffer) memcpy(packet->data, buffer, length); } return packet; } struct hpsb_packet *hpsb_make_streampacket(struct hpsb_host *host, u8 * buffer, int length, int channel, int tag, int sync) { struct hpsb_packet *packet; if (length == 0) return NULL; packet = hpsb_alloc_packet(length); if (!packet) return NULL; if (length % 4) { /* zero padding bytes */ packet->data[length >> 2] = 0; } packet->host = host; /* Because it is too difficult to determine all PHY speeds and link * speeds here, we use S100... */ packet->speed_code = IEEE1394_SPEED_100; /* ...and prevent hpsb_send_packet() from overriding it. */ packet->node_id = LOCAL_BUS | ALL_NODES; if (hpsb_get_tlabel(packet)) { hpsb_free_packet(packet); return NULL; } fill_async_stream_packet(packet, length, channel, tag, sync); if (buffer) memcpy(packet->data, buffer, length); return packet; } struct hpsb_packet *hpsb_make_lockpacket(struct hpsb_host *host, nodeid_t node, u64 addr, int extcode, quadlet_t * data, quadlet_t arg) { struct hpsb_packet *p; u32 length; p = hpsb_alloc_packet(8); if (!p) return NULL; p->host = host; p->node_id = node; if (hpsb_get_tlabel(p)) { hpsb_free_packet(p); return NULL; } switch (extcode) { case EXTCODE_FETCH_ADD: case EXTCODE_LITTLE_ADD: length = 4; if (data) p->data[0] = *data; break; default: length = 8; if (data) { p->data[0] = arg; p->data[1] = *data; } break; } fill_async_lock(p, addr, extcode, length); return p; } struct hpsb_packet *hpsb_make_lock64packet(struct hpsb_host *host, nodeid_t node, u64 addr, int extcode, octlet_t * data, octlet_t arg) { struct hpsb_packet *p; u32 length; p = hpsb_alloc_packet(16); if (!p) return NULL; p->host = host; p->node_id = node; if (hpsb_get_tlabel(p)) { hpsb_free_packet(p); return NULL; } switch (extcode) { case EXTCODE_FETCH_ADD: case EXTCODE_LITTLE_ADD: length = 8; if (data) { p->data[0] = *data >> 32; p->data[1] = *data & 0xffffffff; } break; default: length = 16; if (data) { p->data[0] = arg >> 32; p->data[1] = arg & 0xffffffff; p->data[2] = *data >> 32; p->data[3] = *data & 0xffffffff; } break; } fill_async_lock(p, addr, extcode, length); return p; } struct hpsb_packet *hpsb_make_phypacket(struct hpsb_host *host, quadlet_t data) { struct hpsb_packet *p; p = hpsb_alloc_packet(0); if (!p) return NULL; p->host = host; fill_phy_packet(p, data); return p; } /* * FIXME - these functions should probably read from / write to user space to * avoid in kernel buffers for user space callers */ /** * hpsb_read - generic read function * * Recognizes the local node ID and act accordingly. Automatically uses a * quadlet read request if @length == 4 and and a block read request otherwise. * It does not yet support lengths that are not a multiple of 4. * * You must explicitly specifiy the @generation for which the node ID is valid, * to avoid sending packets to the wrong nodes when we race with a bus reset. */ int hpsb_read(struct hpsb_host *host, nodeid_t node, unsigned int generation, u64 addr, quadlet_t * buffer, size_t length) { struct hpsb_packet *packet; int retval = 0; if (length == 0) return -EINVAL; BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet packet = hpsb_make_readpacket(host, node, addr, length); if (!packet) { return -ENOMEM; } packet->generation = generation; retval = hpsb_send_packet_and_wait(packet); if (retval < 0) goto hpsb_read_fail; retval = hpsb_packet_success(packet); if (retval == 0) { if (length == 4) { *buffer = packet->header[3]; } else { memcpy(buffer, packet->data, length); } } hpsb_read_fail: hpsb_free_tlabel(packet); hpsb_free_packet(packet); return retval; } /** * hpsb_write - generic write function * * Recognizes the local node ID and act accordingly. Automatically uses a * quadlet write request if @length == 4 and and a block write request * otherwise. It does not yet support lengths that are not a multiple of 4. * * You must explicitly specifiy the @generation for which the node ID is valid, * to avoid sending packets to the wrong nodes when we race with a bus reset. */ int hpsb_write(struct hpsb_host *host, nodeid_t node, unsigned int generation, u64 addr, quadlet_t * buffer, size_t length) { struct hpsb_packet *packet; int retval; if (length == 0) return -EINVAL; BUG_ON(in_interrupt()); // We can't be called in an interrupt, yet packet = hpsb_make_writepacket(host, node, addr, buffer, length); if (!packet) return -ENOMEM; packet->generation = generation; retval = hpsb_send_packet_and_wait(packet); if (retval < 0) goto hpsb_write_fail; retval = hpsb_packet_success(packet); hpsb_write_fail: hpsb_free_tlabel(packet); hpsb_free_packet(packet); return retval; }