- Two or more Blackmagic USB3 or PCI cards, either HDMI or SDI.
The PCI cards need Blackmagic's own drivers installed. The USB3 cards
are driven through the “bmusb” driver embedded in bmusb/, using libusb-1.0.
- Note that you will want a recent Linux kernel to avoid LPM (link power
- management) and bandwidth allocation issues with USB3.
+ You want a recent kernel and libusb-1.0; see below.
- Movit, my GPU-based video filter library (https://movit.sesse.net).
You will need at least version 1.3.1.
libavcodec-dev libavformat-dev libswscale-dev libavresample-dev \
libmovit-dev libegl1-mesa-dev libasound2-dev libx264-dev
-Exceptions as of May 2016:
+Exceptions as of June 2016:
- - You want kernel 4.6.0 or newer to get any use of the patches in
- patches/ for persistent USB memory (see next paragraph).
+ - You need libusb 1.0.21 or newer (not yet released; you will need to
+ use git) if you want zerocopy USB. Zerocopy USB helps not only for
+ performance, but also for stability.
+ - You want kernel 4.6.0 or newer to get zerocopy USB. Older kernels
+ also lack some workarounds for LPM (link power management) and bandwidth
+ allocation issues with USB3.
-The patches/ directory contains some patches for upstream software that help
-Nageru performance and/or stability. They are all meant for upstream, but
-probably will not be in by the time Nageru is released. All except the bmusb
-patch are taken to be by Steinar H. Gunderson <sesse@google.com> (ie., my work
-email, unlike Nageru itself and bmusb), and under the same license as the
-projects they patch.
+
+The patches/ directory contains a patch that helps zita-resampler performance.
+It is meant for upstream, but was not in at the time Nageru was released.
+It is taken to be by Steinar H. Gunderson <sesse@google.com> (ie., my ex-work
+email), and under the same license as zita-resampler itself.
To start it, just hook up your equipment, type “make” and then “./nageru”.
It is strongly recommended to have the rights to run at real-time priority;
+++ /dev/null
-From 66c3edf744415f117c3be95ae83f0bab6e128830 Mon Sep 17 00:00:00 2001\r
-From: "Steinar H. Gunderson" <sesse@google.com>\r
-Date: Wed, 9 Dec 2015 10:03:15 +0100\r
-Subject: [PATCH] Add support for persistent device memory.\r
-\r
-Add a function to allocate memory belonging to a specific device,\r
-so that the operating system can DMA straight into it for zerocopy,\r
-and also avoid some clearing. Also, this allows up-front memory\r
-allocation in the kernel at program startup; memory allocation is\r
-otherwise done per-transfer, which can fail in a system where memory has become\r
-fragmented over time).\r
-\r
-This mirrors new functionality going into Linux' USB stack (scheduled\r
-for inclusion in mainline around 4.6); only Linux is supported as a\r
-backend currently.\r
----\r
- libusb/core.c | 29 +++++++++++++++++++++++++++++\r
- libusb/libusb-1.0.def | 4 ++++\r
- libusb/libusb.h | 30 +++++++++++++++++++++++++++++-\r
- libusb/libusbi.h | 10 ++++++++++\r
- libusb/os/linux_usbfs.c | 30 ++++++++++++++++++++++++++++++\r
- 5 files changed, 102 insertions(+), 1 deletion(-)\r
-\r
-diff --git a/libusb/core.c b/libusb/core.c\r
-index 9c617fb..3eba85a 100644\r
---- a/libusb/core.c\r
-+++ b/libusb/core.c\r
-@@ -351,6 +351,8 @@ if (cfg != desired)\r
- * - libusb_control_transfer_get_setup()\r
- * - libusb_cpu_to_le16()\r
- * - libusb_detach_kernel_driver()\r
-+ * - libusb_dev_mem_alloc()\r
-+ * - libusb_dev_mem_free()\r
- * - libusb_error_name()\r
- * - libusb_event_handler_active()\r
- * - libusb_event_handling_ok()\r
-@@ -1805,6 +1807,33 @@ int API_EXPORTED libusb_free_streams(libusb_device_handle *dev,\r
- return LIBUSB_ERROR_NOT_SUPPORTED;\r
- }\r
- \r
-+API_EXPORTED unsigned char *libusb_dev_mem_alloc(libusb_device_handle *dev,\r
-+ int length)\r
-+{\r
-+ if (!dev->dev->attached)\r
-+ return NULL;\r
-+\r
-+ if (usbi_backend->dev_mem_alloc)\r
-+ return usbi_backend->dev_mem_alloc(dev, length);\r
-+ else\r
-+ return NULL;\r
-+}\r
-+\r
-+/* Note: No current backends actually use the "dev" parameter; it is only there\r
-+ * for any future, less lenient OSes.\r
-+ */\r
-+int API_EXPORTED libusb_dev_mem_free(libusb_device_handle *dev,\r
-+ unsigned char *buffer, int len)\r
-+{\r
-+ if (!dev->dev->attached)\r
-+ return LIBUSB_ERROR_NO_DEVICE;\r
-+\r
-+ if (usbi_backend->dev_mem_free)\r
-+ return usbi_backend->dev_mem_free(dev, buffer, len);\r
-+ else\r
-+ return LIBUSB_ERROR_NOT_SUPPORTED;\r
-+}\r
-+\r
- /** \ingroup dev\r
- * Determine if a kernel driver is active on an interface. If a kernel driver\r
- * is active, you cannot claim the interface, and libusb will be unable to\r
-diff --git a/libusb/libusb-1.0.def b/libusb/libusb-1.0.def\r
-index 538ad49..e040f4b 100644\r
---- a/libusb/libusb-1.0.def\r
-+++ b/libusb/libusb-1.0.def\r
-@@ -20,6 +20,10 @@ EXPORTS\r
- libusb_control_transfer@32 = libusb_control_transfer\r
- libusb_detach_kernel_driver\r
- libusb_detach_kernel_driver@8 = libusb_detach_kernel_driver\r
-+ libusb_dev_mem_alloc\r
-+ libusb_dev_mem_alloc@8 = libusb_dev_mem_alloc\r
-+ libusb_dev_mem_free\r
-+ libusb_dev_mem_free@12 = libusb_dev_mem_free\r
- libusb_error_name\r
- libusb_error_name@4 = libusb_error_name\r
- libusb_event_handler_active\r
-diff --git a/libusb/libusb.h b/libusb/libusb.h\r
-index 513945f..5a84f5b 100644\r
---- a/libusb/libusb.h\r
-+++ b/libusb/libusb.h\r
-@@ -141,7 +141,7 @@ typedef unsigned __int32 uint32_t;\r
- * Internally, LIBUSB_API_VERSION is defined as follows:\r
- * (libusb major << 24) | (libusb minor << 16) | (16 bit incremental)\r
- */\r
--#define LIBUSB_API_VERSION 0x01000104\r
-+#define LIBUSB_API_VERSION 0x01000105\r
- \r
- /* The following is kept for compatibility, but will be deprecated in the future */\r
- #define LIBUSBX_API_VERSION LIBUSB_API_VERSION\r
-@@ -1749,6 +1749,34 @@ int LIBUSB_CALL libusb_interrupt_transfer(libusb_device_handle *dev_handle,\r
- unsigned char endpoint, unsigned char *data, int length,\r
- int *actual_length, unsigned int timeout);\r
- \r
-+/** \ingroup asyncio\r
-+ * Attempts to allocate a block of persistent DMA memory suitable for transfers\r
-+ * against the given device. If successful, will return a block of memory\r
-+ * that is suitable for use as "buffer" in \ref libusb_transfer against this\r
-+ * device. Using this memory instead of regular memory means that the host\r
-+ * controller can use DMA directly into the buffer to increase performance, and\r
-+ * also that transfers can no longer fail due to kernel memory fragmentation.\r
-+ *\r
-+ * Note that this means you should not modify this memory (or even data on\r
-+ * the same cache lines) when a transfer is in progress, although it is legal\r
-+ * to have several transfers going on within the same memory block.\r
-+ *\r
-+ * Will return NULL on failure. Many systems do not support such zerocopy\r
-+ * and will always return NULL. Memory allocated with this function must be\r
-+ * freed with \ref libusb_dev_mem_free.\r
-+ *\r
-+ * Since version 1.0.21, \ref LIBUSB_API_VERSION >= 0x01000105\r
-+ *\r
-+ * \param dev a device handle\r
-+ * \param length size of desired data buffer\r
-+ * \returns a pointer to the newly allocated memory, or NULL on failure\r
-+ */\r
-+unsigned char *LIBUSB_CALL libusb_dev_mem_alloc(libusb_device_handle *dev,\r
-+ int length);\r
-+\r
-+int LIBUSB_CALL libusb_dev_mem_free(libusb_device_handle *dev,\r
-+ unsigned char *buffer, int length);\r
-+\r
- /** \ingroup desc\r
- * Retrieve a descriptor from the default control pipe.\r
- * This is a convenience function which formulates the appropriate control\r
-diff --git a/libusb/libusbi.h b/libusb/libusbi.h\r
-index f1afd99..66bdf46 100644\r
---- a/libusb/libusbi.h\r
-+++ b/libusb/libusbi.h\r
-@@ -913,6 +913,16 @@ struct usbi_os_backend {\r
- int (*free_streams)(struct libusb_device_handle *handle,\r
- unsigned char *endpoints, int num_endpoints);\r
- \r
-+ /* Allocate persistent DMA memory for the given device, suitable for\r
-+ * zerocopy. May return NULL on failure. Optional to implement.\r
-+ */\r
-+ unsigned char *(*dev_mem_alloc)(struct libusb_device_handle *handle,\r
-+ size_t len);\r
-+\r
-+ /* Free memory allocated by dev_mem_alloc. */\r
-+ int (*dev_mem_free)(struct libusb_device_handle *handle,\r
-+ unsigned char *buffer, size_t len);\r
-+\r
- /* Determine if a kernel driver is active on an interface. Optional.\r
- *\r
- * The presence of a kernel driver on an interface indicates that any\r
-diff --git a/libusb/os/linux_usbfs.c b/libusb/os/linux_usbfs.c\r
-index a63852f..a167084 100644\r
---- a/libusb/os/linux_usbfs.c\r
-+++ b/libusb/os/linux_usbfs.c\r
-@@ -33,6 +33,7 @@\r
- #include <stdlib.h>\r
- #include <string.h>\r
- #include <sys/ioctl.h>\r
-+#include <sys/mman.h>\r
- #include <sys/stat.h>\r
- #include <sys/types.h>\r
- #include <sys/utsname.h>\r
-@@ -1561,6 +1562,32 @@ static int op_free_streams(struct libusb_device_handle *handle,\r
- endpoints, num_endpoints);\r
- }\r
- \r
-+static unsigned char *op_dev_mem_alloc(struct libusb_device_handle *handle,\r
-+ size_t len)\r
-+{\r
-+ struct linux_device_handle_priv *hpriv = _device_handle_priv(handle);\r
-+ unsigned char *buffer = (unsigned char *)mmap(NULL, len,\r
-+ PROT_READ | PROT_WRITE, MAP_SHARED, hpriv->fd, 0);\r
-+ if (buffer == MAP_FAILED) {\r
-+ usbi_err(HANDLE_CTX(handle), "alloc dev mem failed errno %d",\r
-+ errno);\r
-+ return NULL;\r
-+ }\r
-+ return buffer;\r
-+}\r
-+\r
-+static int op_dev_mem_free(struct libusb_device_handle *handle,\r
-+ unsigned char *buffer, size_t len)\r
-+{\r
-+ if (munmap(buffer, len) != 0) {\r
-+ usbi_err(HANDLE_CTX(handle), "free dev mem failed errno %d",\r
-+ errno);\r
-+ return LIBUSB_ERROR_OTHER;\r
-+ } else {\r
-+ return LIBUSB_SUCCESS;\r
-+ }\r
-+}\r
-+\r
- static int op_kernel_driver_active(struct libusb_device_handle *handle,\r
- int interface)\r
- {\r
-@@ -2682,6 +2709,9 @@ const struct usbi_os_backend linux_usbfs_backend = {\r
- .alloc_streams = op_alloc_streams,\r
- .free_streams = op_free_streams,\r
- \r
-+ .dev_mem_alloc = op_dev_mem_alloc,\r
-+ .dev_mem_free = op_dev_mem_free,\r
-+\r
- .kernel_driver_active = op_kernel_driver_active,\r
- .detach_kernel_driver = op_detach_kernel_driver,\r
- .attach_kernel_driver = op_attach_kernel_driver,\r
--- \r
-2.6.4\r
-\r
projects / nageru / commitdiff