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authorSuren A. Chilingaryan <csa@suren.me>2015-05-05 17:09:46 +0200
committerSuren A. Chilingaryan <csa@suren.me>2015-05-05 17:09:46 +0200
commitc39ac7a604d9f01f602f88f5770b5832e79fcdde (patch)
treeab82c625a8c458d3e5e4e6b65c030867cc486d0e /docs
parent8ba31d8601b157ada318ca60fcb094244807d421 (diff)
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Add doxygen configuration
Diffstat (limited to 'docs')
-rw-r--r--docs/BUGS5
-rw-r--r--docs/Doxyfile.in209
-rw-r--r--docs/NOTES311
-rw-r--r--docs/README11
-rw-r--r--docs/ToDo23
5 files changed, 559 insertions, 0 deletions
diff --git a/docs/BUGS b/docs/BUGS
new file mode 100644
index 0000000..4b0c1cc
--- /dev/null
+++ b/docs/BUGS
@@ -0,0 +1,5 @@
+IPECamera Hardware Bugs
+=======================
+ 1. Strange sequence writting CMOSIS registers
+ 2. Sometimes during DMA streaming register accesses fail
+ 3. The lower 12-bit of bus address are ignored by all hardware
diff --git a/docs/Doxyfile.in b/docs/Doxyfile.in
new file mode 100644
index 0000000..1910d8b
--- /dev/null
+++ b/docs/Doxyfile.in
@@ -0,0 +1,209 @@
+# Doxyfile 1.3.3
+
+#---------------------------------------------------------------------------
+# General configuration options
+#---------------------------------------------------------------------------
+PROJECT_NAME = pcilib
+PROJECT_NUMBER =
+OUTPUT_DIRECTORY = ${PCILIB_DOC_DIR}
+OUTPUT_LANGUAGE = English
+USE_WINDOWS_ENCODING = NO
+EXTRACT_ALL = YES
+EXTRACT_PRIVATE = NO
+EXTRACT_STATIC = NO
+EXTRACT_LOCAL_CLASSES = YES
+HIDE_UNDOC_MEMBERS = NO
+HIDE_UNDOC_CLASSES = NO
+HIDE_FRIEND_COMPOUNDS = NO
+HIDE_IN_BODY_DOCS = NO
+BRIEF_MEMBER_DESC = YES
+REPEAT_BRIEF = YES
+ALWAYS_DETAILED_SEC = NO
+INLINE_INHERITED_MEMB = NO
+FULL_PATH_NAMES = NO
+STRIP_FROM_PATH =
+INTERNAL_DOCS = NO
+CASE_SENSE_NAMES = YES
+SHORT_NAMES = NO
+HIDE_SCOPE_NAMES = NO
+SHOW_INCLUDE_FILES = YES
+JAVADOC_AUTOBRIEF = NO
+MULTILINE_CPP_IS_BRIEF = NO
+DETAILS_AT_TOP = NO
+INHERIT_DOCS = YES
+INLINE_INFO = YES
+SORT_MEMBER_DOCS = YES
+DISTRIBUTE_GROUP_DOC = NO
+TAB_SIZE = 8
+GENERATE_TODOLIST = YES
+GENERATE_TESTLIST = YES
+GENERATE_BUGLIST = YES
+GENERATE_DEPRECATEDLIST= YES
+ALIASES =
+ENABLED_SECTIONS =
+MAX_INITIALIZER_LINES = 30
+OPTIMIZE_OUTPUT_FOR_C = NO
+OPTIMIZE_OUTPUT_JAVA = NO
+SHOW_USED_FILES = YES
+SUBGROUPING = YES
+#---------------------------------------------------------------------------
+# configuration options related to warning and progress messages
+#---------------------------------------------------------------------------
+QUIET = NO
+WARNINGS = YES
+WARN_IF_UNDOCUMENTED = NO
+WARN_IF_DOC_ERROR = YES
+WARN_FORMAT = "$file:$line: $text"
+WARN_LOGFILE =
+#---------------------------------------------------------------------------
+# configuration options related to the input files
+#---------------------------------------------------------------------------
+INPUT = ${CMAKE_SOURCE_DIR}/pcilib/
+FILE_PATTERNS = *.h \
+ *.c
+RECURSIVE = NO
+EXCLUDE =
+EXCLUDE_SYMLINKS = NO
+EXCLUDE_PATTERNS =
+EXAMPLE_PATH =
+EXAMPLE_PATTERNS =
+EXAMPLE_RECURSIVE = NO
+IMAGE_PATH =
+INPUT_FILTER =
+FILTER_SOURCE_FILES = NO
+#---------------------------------------------------------------------------
+# configuration options related to source browsing
+#---------------------------------------------------------------------------
+SOURCE_BROWSER = NO
+INLINE_SOURCES = YES
+STRIP_CODE_COMMENTS = YES
+REFERENCED_BY_RELATION = YES
+REFERENCES_RELATION = YES
+VERBATIM_HEADERS = YES
+#---------------------------------------------------------------------------
+# configuration options related to the alphabetical class index
+#---------------------------------------------------------------------------
+ALPHABETICAL_INDEX = NO
+COLS_IN_ALPHA_INDEX = 5
+IGNORE_PREFIX =
+#---------------------------------------------------------------------------
+# configuration options related to the HTML output
+#---------------------------------------------------------------------------
+GENERATE_HTML = YES
+HTML_OUTPUT = html
+HTML_FILE_EXTENSION = .html
+HTML_HEADER =
+HTML_FOOTER =
+HTML_STYLESHEET =
+HTML_ALIGN_MEMBERS = YES
+GENERATE_HTMLHELP = NO
+CHM_FILE =
+HHC_LOCATION =
+GENERATE_CHI = NO
+BINARY_TOC = NO
+TOC_EXPAND = NO
+DISABLE_INDEX = NO
+ENUM_VALUES_PER_LINE = 4
+GENERATE_TREEVIEW = NO
+TREEVIEW_WIDTH = 250
+#---------------------------------------------------------------------------
+# configuration options related to the LaTeX output
+#---------------------------------------------------------------------------
+GENERATE_LATEX = NO
+LATEX_OUTPUT = latex
+LATEX_CMD_NAME = latex
+MAKEINDEX_CMD_NAME = makeindex
+COMPACT_LATEX = NO
+PAPER_TYPE = a4wide
+EXTRA_PACKAGES =
+LATEX_HEADER =
+PDF_HYPERLINKS = NO
+USE_PDFLATEX = NO
+LATEX_BATCHMODE = NO
+LATEX_HIDE_INDICES = NO
+#---------------------------------------------------------------------------
+# configuration options related to the RTF output
+#---------------------------------------------------------------------------
+GENERATE_RTF = NO
+RTF_OUTPUT = rtf
+COMPACT_RTF = NO
+RTF_HYPERLINKS = NO
+RTF_STYLESHEET_FILE =
+RTF_EXTENSIONS_FILE =
+#---------------------------------------------------------------------------
+# configuration options related to the man page output
+#---------------------------------------------------------------------------
+GENERATE_MAN = NO
+MAN_OUTPUT = man
+MAN_EXTENSION = .3
+MAN_LINKS = NO
+#---------------------------------------------------------------------------
+# configuration options related to the XML output
+#---------------------------------------------------------------------------
+GENERATE_XML = NO
+XML_OUTPUT = xml
+XML_SCHEMA =
+XML_DTD =
+#---------------------------------------------------------------------------
+# configuration options for the AutoGen Definitions output
+#---------------------------------------------------------------------------
+GENERATE_AUTOGEN_DEF = NO
+#---------------------------------------------------------------------------
+# configuration options related to the Perl module output
+#---------------------------------------------------------------------------
+GENERATE_PERLMOD = NO
+PERLMOD_LATEX = NO
+PERLMOD_PRETTY = YES
+PERLMOD_MAKEVAR_PREFIX =
+#---------------------------------------------------------------------------
+# Configuration options related to the preprocessor
+#---------------------------------------------------------------------------
+ENABLE_PREPROCESSING = YES
+MACRO_EXPANSION = NO
+EXPAND_ONLY_PREDEF = NO
+SEARCH_INCLUDES = YES
+INCLUDE_PATH =
+INCLUDE_FILE_PATTERNS =
+PREDEFINED =
+EXPAND_AS_DEFINED =
+SKIP_FUNCTION_MACROS = YES
+#---------------------------------------------------------------------------
+# Configuration::addtions related to external references
+#---------------------------------------------------------------------------
+TAGFILES =
+GENERATE_TAGFILE =
+ALLEXTERNALS = NO
+EXTERNAL_GROUPS = YES
+PERL_PATH = /usr/bin/perl
+#---------------------------------------------------------------------------
+# Configuration options related to the dot tool
+#---------------------------------------------------------------------------
+CLASS_DIAGRAMS = YES
+HIDE_UNDOC_RELATIONS = YES
+HAVE_DOT = NO
+CLASS_GRAPH = YES
+COLLABORATION_GRAPH = YES
+UML_LOOK = NO
+TEMPLATE_RELATIONS = NO
+INCLUDE_GRAPH = YES
+INCLUDED_BY_GRAPH = YES
+CALL_GRAPH = NO
+GRAPHICAL_HIERARCHY = YES
+DOT_IMAGE_FORMAT = png
+DOT_PATH =
+DOTFILE_DIRS =
+MAX_DOT_GRAPH_WIDTH = 1024
+MAX_DOT_GRAPH_HEIGHT = 1024
+MAX_DOT_GRAPH_DEPTH = 0
+GENERATE_LEGEND = YES
+DOT_CLEANUP = YES
+#---------------------------------------------------------------------------
+# Configuration::addtions related to the search engine
+#---------------------------------------------------------------------------
+SEARCHENGINE = NO
+CGI_NAME = search.cgi
+CGI_URL =
+DOC_URL =
+DOC_ABSPATH =
+BIN_ABSPATH = /usr/local/bin/
+EXT_DOC_PATHS =
diff --git a/docs/NOTES b/docs/NOTES
new file mode 100644
index 0000000..d87bbfc
--- /dev/null
+++ b/docs/NOTES
@@ -0,0 +1,311 @@
+Memory Addressing
+=================
+ There is 3 types of addresses: virtual, physical, and bus. For DMA a bus
+ address is used. However, on x86 physical and bus addresses are the same (on
+ other architectures it is not guaranteed). Anyway, this assumption is still
+ used by xdma driver, it uses phiscal address for DMA access. I have ported
+ in the same way. Now, we need to provide additionaly bus-addresses in kmem
+ abstraction and use it in NWL DMA implementation.
+
+DMA Access Synchronization
+==========================
+ - At driver level, few types of buffers are supported:
+ * SIMPLE - non-reusable buffers, the use infomation can be used for cleanup
+ after crashed applications.
+ * EXCLUSIVE - reusable buffers which can be mmaped by a single appliction
+ only. There is two modes of these buffers:
+ + Buffers in a STANDARD mode are created for a single DMA operation and
+ if such buffer is detected while trying to reuse, the last operation
+ has failed and reset is needed.
+ + Buffers in a PERSISTENT mode are preserved between invocations of
+ control application and cleaned up only after the PERSISTENT flag is
+ removed
+ * SHARED - reusable buffers shared by multiple processes. Not really
+ needed at the moment.
+
+ KMEM_FLAG_HW - indicates that buffer can be used by hardware, acually this
+ means that DMA will be enabled afterwards. The driver is not able to check
+ if it really was enable and therefore will block any attempt to release
+ buffer until KMEM_HW_FLAG is passed to kmem_free routine as well. The later
+ should only called with KMEM_HW_FLAG after the DMA engine is stopped. Then,
+ the driver can be realesd by kmem_free if ref count reaches 0.
+
+ KMEM_FLAG_EXCLUSIVE - prevents multiple processes mmaping the buffer
+ simultaneously. This is used to prevent multiple processes use the same
+ DMA engine at the same time. When passed to kmem_free, allows to clean
+ buffers with lost clients even for shared buffers.
+
+ KMEM_FLAG_REUSE - requires reuse of existing buffer. If reusable buffer is
+ found (non-reusable buffers, i.e. allocated without KMEM_FLAG_REUSE are
+ ignored), it is returned instead of allocation. Three types of usage
+ counters are used. At moment of allocation, the HW reference is set if
+ neccessary. The usage counter is increased by kmem_alloc function and
+ decreased by kmem_free. Finally, the reference is obtained at returned
+ during mmap/munmap. So, on kmem_free, we do not clean
+ a) buffers with reference count above zero or hardware reference set.
+ REUSE flag should be supplied, overwise the error is returned
+ b) PERSISTENT buffer. REUSE flash should be supplied, overwise the
+ error is returned
+ c) non-exclusive buffers with usage counter above zero (For exclusive
+ buffer the value of usage counter above zero just means that application
+ have failed without cleaning buffers first. There is no easy way to
+ detect that for shared buffers, so it is left as manual operation in
+ this case)
+ d) any buffer if KMEM_FLAG_REUSE was provided to function
+ During module unload, only buffers with references can prevent cleanup. In
+ this case the only possiblity to free the driver is to call kmem_free
+ passing FORCE flags.
+
+ KMEM_FLAG_PERSISTENT - if passed to allocation routine, changes mode of
+ buffer to PERSISTENT, if passed to free routine, vice-versa changes mode
+ of buffer to NORMAL. Basically, if we call 'pci --dma-start' this flag
+ should be passed to alloc and if we call 'pci --dma-stop' it should be
+ passed to free. In other case, the flag should not be present.
+
+ If application crashed, the munmap while be still called cleaning software
+ references. However, the hardware reference will stay since it is not clear
+ if hardware channel was closed or not. To lift hardware reference, the
+ application can be re-executed (or dma_stop called, for instance).
+ * If there is no hardware reference, the buffers will be reused by next
+ call to application and for EXCLUSIVE buffer cleaned at the end. For SHARED
+ buffers they will be cleaned during module cleanup only (no active
+ references).
+ * The buffer will be reused by next call which can result in wrong behaviour
+ if buffer left in incoherent stage. This should be handled on upper level.
+
+ - At pcilib/kmem level synchronization of multiple buffers is performed
+ * The HW reference and following modes should be consistent between member
+ parts: REUSABLE, PERSISTENT, EXCLUSIVE (only HW reference and PERSISTENT
+ mode should be checked, others are handled on dirver level)
+ * It is fine if only part of buffers are reused and others are newly
+ allocated. However, on higher level this can be checked and resulting
+ in failure.
+
+ Treatment of inconsistencies:
+ * Buffers are in PRESISTENT mode, but newly allocated, OK
+ * Buffers are reused, but are not in PERSISTENT mode (for EXCLUSIVE buffers
+ this means that application has crashed during the last execution), OK
+ * Some of buffers are reused (not just REUSABLE, but actually reused),
+ others - not, OK until
+ a) either PERSISTENT flag is set or reused buffers are non-PERSISTENT
+ b) either HW flag is set or reused buffers does not hold HW reference
+ * PERSISTENT mode inconsistency, FAIL (even if we are going to set
+ PERSISTENT mode anyway)
+ * HW reference inconsistency, FAIL (even if we are going to set
+ HW flag anyway)
+
+ On allocation error at some of the buffer, call clean routine and
+ * Preserve PERSISTENT mode and HW reference if buffers held them before
+ unsuccessful kmem initialization. Until the last failed block, the blocks
+ of kmem should be consistent. The HW/PERSISTENT flags should be removed
+ if all reused blocks were in HW/PERSISTENT mode. The last block needs
+ special treatment. The flags may be removed for the block if it was
+ HW/PERSISTENT state (and others not).
+ * Remove REUSE flag, we want to clean if allowed by current buffer status
+ * EXCLUSIVE flag is not important for kmem_free routine.
+
+ - At DMA level
+ There is 4 components of DMA access:
+ * DMA engine enabled/disabled
+ * DMA engine IRQs enabled/disabled - always enabled at startup
+ * Memory buffers
+ * Ring start/stop pointers
+
+ To prevent multiple processes accessing DMA engine in parallel, the first
+ action is buffer initialization which will fail if buffers already used
+ * Always with REUSE, EXCLUSIVE, and HW flags
+ * Optionally with PERSISTENT flag (if DMA_PERSISTENT flag is set)
+ If another DMA app is running, the buffer allocation will fail (no dma_stop
+ is executed in this case)
+
+ Depending on PRESERVE flag, kmem_free will be called with REUSE flag
+ keeping buffer in memory (this is redundant since HW flag is enough) or HW
+ flag indicating that DMA engine is stopped and buffer could be cleaned.
+ PERSISTENT flag is defined by DMA_PERSISTENT flag passed to stop routine.
+
+ PRESERVE flag is enforced if DMA_PERSISTENT is not passed to dma_stop
+ routine and either it:
+ a) Explicitely set by DMA_PERMANENT flag passed to dma_start
+ function
+ b) Implicitely set if DMA engine is already enabled during dma_start,
+ all buffers are reused, and are in persistent mode.
+ If PRESERVE flag is on, the engine will not be stopped at the end of
+ execution (and buffers will stay because of HW flag).
+
+ If buffers are reused and are already in PERSISTENT mode, DMA engine was on
+ before dma_start (PRESERVE flag is ignored, because it can be enforced),
+ ring pointers are calculated from LAST_BD and states of ring elements.
+ If previous application crashed (i.e. buffers may be corrupted). Two
+ cases are possible:
+ * If during the call buffers were in non-PERSISTENT mode, it can be
+ easily detected - buffers are reused, but are not in PERSISTENT mode
+ (or at least was not before we set them to). In this case we just
+ reinitialize all buffers.
+ * If during the call buffers were in PERSISTENT mode, it is up to
+ user to check their consistency and restart DMA engine.]
+
+ IRQs are enabled and disabled at each call
+
+DMA Reads
+=========
+standard: default reading mode, reads a single full packet
+multipacket: reads all available packets
+waiting multipacket: reads all available packets, after finishing the
+ last one waiting if new data arrives
+exact read: read exactly specified number of bytes (should be
+ only supported if it is multiple of packets, otherwise
+ error should be returned)
+ignore packets: autoterminate each buffer, depends on engine
+ configuration
+
+ To handle differnt cases, the value returned by callback function instructs
+the DMA library how long to wait for the next data to appear before timing
+out. The following variants are possible:
+terminate: just bail out
+check: no timeout, just check if there is data, otherwise
+ terminate
+timeout: standard DMA timeout, normaly used while receiving
+ fragments of packet: in this case it is expected
+ that device has already prepared data and only
+ the performance of DMA engine limits transfer speed
+wait: wait until the data is prepared by the device, this
+ timeout is specified as argument to the dma_stream
+ function (standard DMA timeout is used by default)
+
+ first | new_pkt | bufer
+ --------------------------
+standard wait | term | timeout
+multiple packets wait | check | timeout - DMA_READ_FLAG_MULTIPACKET
+waiting multipacket wait | wait | timeout - DMA_READ_FLAG_WAIT
+exact wait | wait/term | timeout - limited by size parameter
+ignore packets wait | wait/check| wait/check - just autoterminated
+
+Shall we do a special handling in case of overflow?
+
+
+Buffering
+=========
+ The DMA addresses are limited to 32 bits (~4GB for everything). This means we
+ can't really use DMA pages are sole buffers. Therefore, a second thread, with
+ a realtime scheduling policy if possible, will be spawned and will copy the
+ data from the DMA pages into the allocated buffers. On expiration of duration
+ or number of events set by autostop call, this thread will be stopped but
+ processing in streaming mode will continue until all copyied data is passed
+ to the callbacks.
+
+ To avoid stalls, the IPECamera requires data to be read continuously read out.
+ For this reason, there is no locks in the readout thread. It will simplify
+ overwrite the old frames if data is not copied out timely. To handle this case
+ after getting the data and processing it, the calling application should use
+ return_data function and check return code. This function may return error
+ indicating that the data was overwritten meanwhile. Hence, the data is
+ corrupted and shoud be droped by the application. The copy_data function
+ performs this check and user application can be sure it get coherent data
+ in this case.
+
+ There is a way to avoid this problem. For raw data, the rawdata callback
+ can be requested. This callback blocks execution of readout thread and
+ data may be treated safely by calling application. However, this may
+ cause problems to electronics. Therefore, only memcpy should be performed
+ on the data normally.
+
+ The reconstructed data, however, may be safely accessed. As described above,
+ the raw data will be continuously overwritten by the reader thread. However,
+ reconstructed data, upon the get_data call, will be protected by the mutex.
+
+
+Register Access Synchronization
+===============================
+ We need to serialize access to the registers by the different running
+ applications and handle case when registers are accessed indirectly by
+ writting PCI BARs (DMA implementations, for instance).
+
+ - Module-assisted locking:
+ * During initialization the locking context is created (which is basicaly
+ a kmem_handle of type LOCK_PAGE.
+ * This locking context is passed to the kernel module along with lock type
+ (LOCK_BANK) and lock item (BANK ADDRESS). If lock context is already owns
+ lock on the specified bank, just reference number is increased, otherwise
+ we are trying to obtain new lock.
+ * Kernel module just iterates over all registered lock pages and checks if
+ any holds the specified lock. if not, the lock is obtained and registered
+ in the our lock page.
+ * This allows to share access between multiple threads of single application
+ (by using the same lock page) or protect (by using own lock pages by each of
+ the threads)
+ * Either on application cleanup or if application crashed, the memory mapping
+ of lock page is removed and, hence, locks are freed.
+
+ - Multiple-ways of accessing registers
+ Because of reference counting, we can successfully obtain locks multiple
+ times if necessary. The following locks are protecting register access:
+ a) Global register_read/write lock bank before executing implementation
+ b) DMA bank is locked by global DMA functions. So we can access the
+ registers using plain PCI bar read/write.
+ c) Sequence of register operations can be protected with pcilib_lock_bank
+ function
+ Reading raw register space or PCI bank is not locked.
+ * Ok. We can detect banks which will be affected by PCI read/write and
+ lock them. But shall we do it?
+
+Register/DMA Configuration
+==========================
+ - XML description of registers
+ - Formal XML-based (or non XML-based) language for DMA implementation.
+ a) Writting/Reading register values
+ b) Wait until <register1>=<value> on <register2>=<value> report error
+ c) ... ?
+
+IRQ Handling
+============
+ IRQ types: DMA IRQ, Event IRQ, other types
+ IRQ hardware source: To allow purely user-space implementation, as general
+ rule, only a single (standard) source should be used.
+ IRQ source: The dma/event engines, however, may detail this hardware source
+ and produce real IRQ source basing on the values of registers. For example,
+ for DMA IRQs the source may present engine number and for Event IRQs the
+ source may present event type.
+
+ Only types can be enabled or disabled. The sources are enabled/disabled
+ by enabling/disabling correspondent DMA engines or Event types. The expected
+ workflow is following:
+ * We enabling IRQs in user-space (normally setting some registers). Normally,
+ just an Event IRQs, the DMA if necessary will be managed by DMA engine itself.
+ * We waiting for standard IRQ from hardware (driver)
+ * In the user space, we are checking registers to find out the real source
+ of IRQ (driver reports us just hardware source), generating appropriate
+ events, and acknowledge IRQ. This is dependent on implementation and should
+ be managed inside event API.
+
+ I.e. the driver implements just two methods pcilib_wait_irq(hw_source),
+ pcilib_clear_irq(hw_source). Only a few hardware IRQ sources are defined.
+ In most cirstumances, the IRQ_SOURCE_DEFAULT is used.
+
+ The DMA engine may provide 3 additional methods, to enable, disable,
+ and acknowledge IRQ.
+
+ ... To be decided in details upon the need...
+
+Updating Firmware
+=================
+ - JTag should be connected to USB connector on the board (next to Ethernet)
+ - The computer should be tourned off and on before programming
+ - The environment variable should be loaded
+ . /home/uros/.bashrc
+ - The application is called 'impact'
+ No project is needed, cancel initial proposals (No/Cancel)
+ Double-click on "Boundary Scan"
+ Right click in the right window and select "Init Chain"
+ We don't want to select bit file now (Yes and, then, click Cancel)
+ Right click on second (right) item and choose "Assign new CF file"
+ Select a bit file. Answer No, we don't want to attach SPI to SPI Prom
+ Select xv6vlx240t and program it
+ - Shutdown and start computer
+
+ Firmware are in
+ v.2: /home/uros/Repo/UFO2_last_good_version_UFO2.bit
+ v.3: /home/uros/Repo/UFO3
+ Step5 - best working revision
+ Step6 - last revision
+
+ \ No newline at end of file
diff --git a/docs/README b/docs/README
new file mode 100644
index 0000000..1cbf8ee
--- /dev/null
+++ b/docs/README
@@ -0,0 +1,11 @@
+Supported environmental variables
+=================================
+ PCILIB_PLUGIN_DIR - override path to directory with plugins
+
+ PCILIB_DEBUG_DMA - Enable DMA debugging
+ PCILIB_DEBUG_MISSING_EVENTS - Enable debugging of missing events (frames for instance)
+ IPECAMERA_DEBUG_BROKEN_FRAMES - Store broken frames in the specified directory (variable may specify directory)
+ IPECAMERA_DEBUG_RAW_PACKETS - Store all raw packets read from DMA grouped in frames (variable may specify directory)
+ IPECAMERA_DEBUG_RAW_FRAMES - Store all raw frames (variable may specify directory)
+ IPECAMERA_DEBUG_HARDWARE - Produce various debugging information about ipecamera operation
+ \ No newline at end of file
diff --git a/docs/ToDo b/docs/ToDo
new file mode 100644
index 0000000..4c2c783
--- /dev/null
+++ b/docs/ToDo
@@ -0,0 +1,23 @@
+High Priority (we would need it for IPE Camera)
+=============
+ 1. Serialize access to the registers across applications
+ 2. Protect kmem_entries in the driver using spinlock
+ 3. Protect mmap operation (multiple kernel calls) with some locking mechanism
+ 4. Allow overriding of registers and banks (performance?).
+
+Normal Priority (it would make just few things a bit easier)
+===============
+ 1. Implement software registers (stored in kernel-memory)
+ 2. Implement pcilib_configure_autotrigger
+ 3. Provide OR and AND operations on registers in cli
+ 4. Support writting a data from a binary file in cli
+
+Low Priority (only as generalization for other projects)
+============
+ 1. XML configurations describing registers (and DMA engines?)
+ 2. Access register/bank lookups using hash tables
+ 3. Support for Network Registers and Network DMA
+ 4. Define a syntax for register dependencies / delays (?)
+ 5. Use pthread_condition_t instead of polling
+ 6. Support FIFO reads/writes from/to registers
+