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path: root/drivers/ieee1394/ieee1394_transactions.c
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-rw-r--r--drivers/ieee1394/ieee1394_transactions.c572
1 files changed, 572 insertions, 0 deletions
diff --git a/drivers/ieee1394/ieee1394_transactions.c b/drivers/ieee1394/ieee1394_transactions.c
new file mode 100644
index 0000000..10c3d9f
--- /dev/null
+++ b/drivers/ieee1394/ieee1394_transactions.c
@@ -0,0 +1,572 @@
+/*
+ * 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;
+}
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