Attachment 274241 Details for Bug 344851 – Upstream version of FireWire OHCI 1.0 Iso Receive patch

[patch] Upstream version of FireWire OHCI 1.0 Iso Receive patch

linux1394-2.6-firewire-ohci10-iso-receive-v2.patch (text/plain), 10.10 KB, created by Jarod Wilson on 2007-11-30 19:14:27 UTC

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Creator: Jarod Wilson

Created: 2007-11-30 19:14:27 UTC

Size: 10.10 KB

patch

obsolete

>Second version of FireWire OHCI 1.0 Isochronous Receive support, this time
>using a zero-copy method similar to 1.1 which puts the IR data payload directly
>into the userspace buffer. This zero-copy implementation eliminates the
>video artifacts, audio popping, and buffer underrun problems seen with the
>prior version.
>
>Successfully tested on the following chipsets:
>
>- Agere FW323 (rev 06), OHCI 1.0 (PCI)
>- Agere FW323 (rev 61), OHCI 1.0 (PCI)
>- NEC uPD72847 (rev 01), OHCI 1.1 (PCI)
>- Ti XIO2200(A) (rev 01), OHCI 1.1 (PCIe)
>- Via VT6306 (rev 46), OHCI 1.0 (PCI)
>
>The 1.1 controllers were forced into the OHCI 1.0 packet-per-buffer mode for
>testing purposes. The bulk of testing was done in a core 2 duo system, but I
>also gave the code a quick spin in an EPIA M10k. The cpu utilization during
>capture sat around 13% on a 1GHz Via C3, down from 30% with the earlier code.
>
>
>Some implementation details:
>
>To maintain the same userspace API as dual-buffer mode, we set up two
>descriptors for every incoming packet. The first is an INPUT_MORE descriptor,
>pointing to a buffer large enough to hold just the packet's iso headers,
>immediately followed by an INPUT_LAST descriptor, pointing to a chunk of the
>userspace buffer big enough for the packet's data payload. With this setup,
>each incoming packet fills in these two descriptors in a manner that very
>closely emulates dual-buffer receive, to the point where the bulk of the
>handle_ir_* code is now identical between the two (and probably primed for
>some restructuring to share code between them).
>
>The only caveat I have at the moment is that neither of my OHCI 1.0 Via
>VT6307-based FireWire controllers work particularly well with this code
>for reasons I have yet to figure out.
>
>Signed-off-by: Jarod Wilson <jwilson@redhat.com>
>
> drivers/firewire/fw-ohci.c |  170 ++++++++++++++++++++++++++++++++++++++-----
> 1 files changed, 150 insertions(+), 20 deletions(-)
>
>diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
>index c9b9081..dc8c2ae 100644
>--- a/drivers/firewire/fw-ohci.c
>+++ b/drivers/firewire/fw-ohci.c
>@@ -437,6 +437,16 @@ static void ar_context_run(struct ar_context *ctx)
> 	flush_writes(ctx->ohci);
> }
> 
>+static struct descriptor *
>+find_branch_descriptor(struct descriptor *d, int z)
>+{
>+	/* figure out which descriptor the branch address goes in */
>+	if (z == 2 && (le16_to_cpu(d->control) & DESCRIPTOR_KEY_IMMEDIATE))
>+		return d;
>+	else
>+		return d + z - 1;
>+}
>+
> static void context_tasklet(unsigned long data)
> {
> 	struct context *ctx = (struct context *) data;
>@@ -455,7 +465,7 @@ static void context_tasklet(unsigned long data)
> 		address = le32_to_cpu(last->branch_address);
> 		z = address & 0xf;
> 		d = ctx->buffer + (address - ctx->buffer_bus) / sizeof(*d);
>-		last = (z == 2) ? d : d + z - 1;
>+		last = find_branch_descriptor(d, z);
> 
> 		if (!ctx->callback(ctx, d, last))
> 			break;
>@@ -566,7 +576,7 @@ static void context_append(struct context *ctx,
> 
> 	ctx->head_descriptor = d + z + extra;
> 	ctx->prev_descriptor->branch_address = cpu_to_le32(d_bus | z);
>-	ctx->prev_descriptor = z == 2 ? d : d + z - 1;
>+	ctx->prev_descriptor = find_branch_descriptor(d, z);
> 
> 	dma_sync_single_for_device(ctx->ohci->card.device, ctx->buffer_bus,
> 				   ctx->buffer_size, DMA_TO_DEVICE);
>@@ -655,7 +665,7 @@ at_context_queue_packet(struct context *ctx, struct fw_packet *packet)
> 	driver_data = (struct driver_data *) &d[3];
> 	driver_data->packet = packet;
> 	packet->driver_data = driver_data;
>-	
>+
> 	if (packet->payload_length > 0) {
> 		payload_bus =
> 			dma_map_single(ohci->card.device, packet->payload,
>@@ -903,7 +913,7 @@ at_context_transmit(struct context *ctx, struct fw_packet *packet)
> 
> 	if (retval < 0)
> 		packet->callback(packet, &ctx->ohci->card, packet->ack);
>-	
>+
> }
> 
> static void bus_reset_tasklet(unsigned long data)
>@@ -1431,6 +1441,57 @@ static int handle_ir_dualbuffer_packet(struct context *context,
> 	return 1;
> }
> 
>+static int handle_ir_packet_per_buffer(struct context *context,
>+				       struct descriptor *d,
>+				       struct descriptor *last)
>+{
>+	struct iso_context *ctx =
>+		container_of(context, struct iso_context, context);
>+	struct descriptor *pd = d + 1;
>+	__le32 *ir_header;
>+	size_t header_length;
>+	void *p, *end;
>+	int i, z;
>+
>+	if (pd->res_count == pd->req_count)
>+		/* Descriptor(s) not done yet, stop iteration */
>+		return 0;
>+
>+	header_length = le16_to_cpu(d->req_count);
>+
>+	i   = ctx->header_length;
>+	z   = le32_to_cpu(pd->branch_address) & 0xf;
>+	p   = d + z;
>+	end = p + header_length;
>+
>+	while (p < end && i + ctx->base.header_size <= PAGE_SIZE) {
>+		/*
>+		 * The iso header is byteswapped to little endian by
>+		 * the controller, but the remaining header quadlets
>+		 * are big endian.  We want to present all the headers
>+		 * as big endian, so we have to swap the first quadlet.
>+		 */
>+		*(u32 *) (ctx->header + i) = __swab32(*(u32 *) (p + 4));
>+		memcpy(ctx->header + i + 4, p + 8, ctx->base.header_size - 4);
>+		i += ctx->base.header_size;
>+		p += ctx->base.header_size + 4;
>+	}
>+
>+	ctx->header_length = i;
>+
>+	if (le16_to_cpu(pd->control) & DESCRIPTOR_IRQ_ALWAYS) {
>+		ir_header = (__le32 *) (d + z);
>+		ctx->base.callback(&ctx->base,
>+				   le32_to_cpu(ir_header[0]) & 0xffff,
>+				   ctx->header_length, ctx->header,
>+				   ctx->base.callback_data);
>+		ctx->header_length = 0;
>+	}
>+
>+
>+	return 1;
>+}
>+
> static int handle_it_packet(struct context *context,
> 			    struct descriptor *d,
> 			    struct descriptor *last)
>@@ -1466,14 +1527,12 @@ ohci_allocate_iso_context(struct fw_card *card, int type, size_t header_size)
> 	} else {
> 		mask = &ohci->ir_context_mask;
> 		list = ohci->ir_context_list;
>-		callback = handle_ir_dualbuffer_packet;
>+		if (ohci->version >= OHCI_VERSION_1_1)
>+			callback = handle_ir_dualbuffer_packet;
>+		else
>+			callback = handle_ir_packet_per_buffer;
> 	}
> 
>-	/* FIXME: We need a fallback for pre 1.1 OHCI. */
>-	if (callback == handle_ir_dualbuffer_packet &&
>-	    ohci->version < OHCI_VERSION_1_1)
>-		return ERR_PTR(-ENOSYS);
>-
> 	spin_lock_irqsave(&ohci->lock, flags);
> 	index = ffs(*mask) - 1;
> 	if (index >= 0)
>@@ -1532,7 +1591,9 @@ static int ohci_start_iso(struct fw_iso_context *base,
> 		context_run(&ctx->context, match);
> 	} else {
> 		index = ctx - ohci->ir_context_list;
>-		control = IR_CONTEXT_DUAL_BUFFER_MODE | IR_CONTEXT_ISOCH_HEADER;
>+		control = IR_CONTEXT_ISOCH_HEADER;
>+		if (ohci->version >= OHCI_VERSION_1_1)
>+			control |= IR_CONTEXT_DUAL_BUFFER_MODE;
> 		match = (tags << 28) | (sync << 8) | ctx->base.channel;
> 		if (cycle >= 0) {
> 			match |= (cycle & 0x07fff) << 12;
>@@ -1738,7 +1799,6 @@ ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base,
> 	offset   = payload & ~PAGE_MASK;
> 	rest     = p->payload_length;
> 
>-	/* FIXME: OHCI 1.0 doesn't support dual buffer receive */
> 	/* FIXME: make packet-per-buffer/dual-buffer a context option */
> 	while (rest > 0) {
> 		d = context_get_descriptors(&ctx->context,
>@@ -1777,6 +1837,81 @@ ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base,
> }
> 
> static int
>+ohci_queue_iso_receive_packet_per_buffer(struct fw_iso_context *base,
>+					 struct fw_iso_packet *packet,
>+					 struct fw_iso_buffer *buffer,
>+					 unsigned long payload)
>+{
>+	struct iso_context *ctx = container_of(base, struct iso_context, base);
>+	struct descriptor *d = NULL, *pd = NULL;
>+	struct fw_iso_packet *p;
>+	dma_addr_t d_bus, page_bus;
>+	u32 z, header_z, rest;
>+	int i, page, offset, packet_count, header_size;
>+
>+	if (packet->skip) {
>+		d = context_get_descriptors(&ctx->context, 1, &d_bus);
>+		if (d == NULL)
>+			return -ENOMEM;
>+
>+		d->control = cpu_to_le16(DESCRIPTOR_STATUS |
>+					 DESCRIPTOR_INPUT_LAST |
>+					 DESCRIPTOR_BRANCH_ALWAYS |
>+					 DESCRIPTOR_WAIT);
>+		context_append(&ctx->context, d, 1, 0);
>+	}
>+
>+	/* one descriptor for header, one for payload */
>+	/* FIXME: handle cases where we need multiple desc. for payload */
>+	z = 2;
>+	p = packet;
>+
>+	/*
>+	 * The OHCI controller puts the status word in the
>+	 * buffer too, so we need 4 extra bytes per packet.
>+	 */
>+	packet_count = p->header_length / ctx->base.header_size;
>+	header_size  = packet_count * (ctx->base.header_size + 4);
>+
>+	/* Get header size in number of descriptors. */
>+	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
>+	page     = payload >> PAGE_SHIFT;
>+	offset   = payload & ~PAGE_MASK;
>+	rest     = p->payload_length;
>+
>+	for (i = 0; i < packet_count; i++) {
>+		/* d points to the header descriptor */
>+		d = context_get_descriptors(&ctx->context,
>+					    z + header_z, &d_bus);
>+		if (d == NULL)
>+			return -ENOMEM;
>+
>+		d->control      = cpu_to_le16(DESCRIPTOR_INPUT_MORE);
>+		d->req_count    = cpu_to_le16(header_size);
>+		d->res_count    = d->req_count;
>+		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));
>+
>+		/* pd points to the payload descriptor */
>+		pd = d + 1;
>+		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
>+					  DESCRIPTOR_INPUT_LAST |
>+					  DESCRIPTOR_BRANCH_ALWAYS);
>+		if (p->interrupt)
>+			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);
>+
>+		pd->req_count = cpu_to_le16(rest);
>+		pd->res_count = pd->req_count;
>+
>+		page_bus = page_private(buffer->pages[page]);
>+		pd->data_address = cpu_to_le32(page_bus + offset);
>+
>+		context_append(&ctx->context, d, z, header_z);
>+	}
>+
>+	return 0;
>+}
>+
>+static int
> ohci_queue_iso(struct fw_iso_context *base,
> 	       struct fw_iso_packet *packet,
> 	       struct fw_iso_buffer *buffer,
>@@ -1790,8 +1925,9 @@ ohci_queue_iso(struct fw_iso_context *base,
> 		return ohci_queue_iso_receive_dualbuffer(base, packet,
> 							 buffer, payload);
> 	else
>-		/* FIXME: Implement fallback for OHCI 1.0 controllers. */
>-		return -ENOSYS;
>+		return ohci_queue_iso_receive_packet_per_buffer(base, packet,
>+								buffer,
>+								payload);
> }
> 
> static const struct fw_card_driver ohci_driver = {
>@@ -1911,12 +2047,6 @@ pci_probe(struct pci_dev *dev, const struct pci_device_id *ent)
> 	ohci->version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
> 	fw_notify("Added fw-ohci device %s, OHCI version %x.%x\n",
> 		  dev->dev.bus_id, ohci->version >> 16, ohci->version & 0xff);
>-	if (ohci->version < OHCI_VERSION_1_1) {
>-		fw_notify("    Isochronous I/O is not yet implemented for "
>-			  "OHCI 1.0 chips.\n");
>-		fw_notify("    Cameras, audio devices etc. won't work on "
>-			  "this controller with this driver version.\n");
>-	}
> 	return 0;
> 
>  fail_self_id:

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Attachments on bug 344851: 233701 | 257711 | 274231 | 274241 | 275941 | 275971