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o USB (drivers/usbdev, drivers/usbhost)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Title: USB STORAGE DRIVER DELAYS
Description: There is a workaround for a bug in drivers/usbdev/usbdev_storage.c.
that involves delays. This needs to be redesigned to eliminate these
delays. See logic conditioned on CONFIG_USBMSC_RACEWAR.
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If queuing of stall requests is supported by DCD then this workaround
is not required. In this case, (1) the stall is not sent until all
write requests preceding the stall request are sent, (2) the stall is
sent, and then after the stall is cleared, (3) all write requests
queued after the stall are sent.
See, for example, the queuing of pending stall requests in the SAM3/4
UDP driver at arch/arm/src/sam34/sam_udp.c. There the logic is do this
is implemented with a normal request queue, a pending request queue, a
stall flag and a stall pending flag:
1) If the normal request queue is not empty when the STALL request is
received, the stall pending flag is set.
2) If addition write requests are received while the stall pending flag
is set (or while waiting for the stall to be sent), those write requests
go into the pending queue.
3) When the normal request queue empties successful and all of the write
transfers complete, the STALL is sent. The stall pending flag is
cleared and the stall flag is set. Now the endpoint is really stalled.
4) After the STALL is cleared (via the Clear Feature SETUP), the pending
request queue is copied to the normal request queue, the stall flag is
cleared, and normal write request processing resumes.
Title: EP0 OUT CLASS DATA
Description: There is no mechanism in place to handle EP0 OUT data transfers.
There are two aspects to this problem, neither are easy to fix
(only because of the number of drivers that would be impacted):
1. The class drivers only send EP0 write requests and these are
only queued on EP0 IN by this drivers. There is never a read
request queued on EP0 OUT.
2. But EP0 OUT data could be buffered in a buffer in the driver
data structure. However, there is no method currently
defined in the USB device interface to obtain the EP0 data.
Updates: (1) The USB device-to-class interface as been extended so
that EP0 OUT data can accompany the SETUP request sent to the
class drivers. (2) The logic in the STM32 F4 OTG FS device driver
has been extended to provide this data. Updates are still needed
to other drivers.
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Here is an overview of the required changes:
New two buffers in driver structure:
1. The existing EP0 setup request buffer (ctrlreq, 8 bytes)
2. A new EP0 data buffer to driver state structure (ep0data,
max packetsize)
Add a new state:
3. Waiting for EP0 setup OUT data (EP0STATE_SETUP_OUT)
General logic flow:
1. When an EP0 SETUP packet is received:
- Read the request into EP0 setup request buffer (ctrlreq,
8 bytes)
- If this is an OUT request with data length, set the EP0
state to EP0STATE_SETUP_OUT and wait to receive data on
EP0.
- Otherwise, the SETUP request may be processed now (or,
in the case of the F4 driver, at the conclusion of the
SETUP phase).
2. When EP0 the EP0 OUT DATA packet is received:
- Verify state is EP0STATE_SETUP_OUT
- Read the request into the EP0 data buffer (ep0data, max
packet size)
- Now process the previously buffered SETUP request along
with the OUT data.
3. When the setup packet is dispatched to the class driver,
the OUT data must be passed as the final parameter in the
call.
Update 2013-9-2: The new USB device-side driver for the SAMA5D3
correctly supports OUT SETUP data following the same design as
per above.
Update 2013-11-7: David Sidrane has fixed with issue with the
STM32 F1 USB device driver. Still a few more to go before this
can be closed out.
Status: Open
Priority: High for class drivers that need EP0 data. For example, the
CDC/ACM serial driver might need the line coding data (that
Title: IMPROVED USAGE of STM32 USB RESOURCES
Description: The STM32 platforms use a non-standard, USB host peripheral
that uses "channels" to implement data transfers the current
logic associates each channel with an pipe/endpoint (with two
channels for bi-directional control endpoints). The OTGFS
peripheral has 8 channels and the OTGHS peripheral has 12
channels.
This works okay until you add a hub and try connect multiple
devices. A typical device will require 3-4 pipes and, hence,
4-5 channels. This effectively prevents using a hub with the
STM32 devices. This also applies to the EFM32 which uses the
same IP.
It should be possible to redesign the STM32 F4 OTGHS/OTGFS and
EFM32 host driver so that channels are dynamically assigned to
pipes as needed for individual transfers. Then you could have
more "apparent" pipes and make better use of channels.
Although there are only 8 or 12 channels, transfers are not
active all of the time on all channels so it ought to be
possible to have an unlimited number of "pipes" but with no
more than 8 or 12 active transfers.
Status: Open
Priority: Medium-Low
Title: USB CDC/ACM HOST CLASS DRIVER
Desciption: A CDC/ACM host class driver has been added. This has been
testing by running the USB CDC/ACM host on an Olimex
LPC1766STK and using the configs/stm3210e-eval/usbserial
configuration (using the CDC/ACM device side driver). There
are several unresolved issues that prevent the host driver
from being usable:
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- The driver works fine when configured for reduced or bulk-
only protocol.
- Testing has not been performed with the interrupt IN channel
enabled (ie., I have not enabled FLOW control nor do I have
a test case that used the interrupt IN channel). I can see
that the polling for interrupt IN data is occurring
initially.
- I test for incoming data by doing 'nsh> cat /dev/ttyACM0' on
the Olimex LPC1766STK host. The bulk data reception still
works okay whether or not the interupt IN channel is enabled.
If the interrupt IN channel is enabled, then polling of that
channel appears to stop when the bulk in channel becomes
active.
- The RX reception logic uses the low priority work queue.
However, that logic never returns and so blocks other use of
the work queue thread. This is probably okay but means that
the RX reception logic probably should be moved to its own
dedicated thread.
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- I get crashes when I run with the STM32 OTGHS host driver.
Apparently the host driver is trashing memory on receipt
of data.
- The SAMA5D EHCI and the LPC31 EHCI drivers both take semaphores
in the cancel method. The current CDC/ACM class driver calls
the cancel() method from an interrupt handler. This will
cause a crash. Those EHCI drivers should be redesigned to
permit cancellation from the interrupt level.
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Most of these problems are unique to the Olimex LPC1766STK
DCD; some are probably design problems in the CDC/ACM host
driver. The bottom line is that the host CDC/ACM driver is
still immature and you could experience issues in some
configurations if you use it.
That all being said, I know of know no issues with the current
CDC/ACM driver if the interrupt IN endpoint is not used, i.e.,
in "reduced" mode. The only loss of functionality is output
flow control.
Status: Open
Priority: Medium-Low unless you really need host CDC/ACM support.
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o Libraries (libc/)
^^^^^^^^^^^^^^^^^
Title: SIGNED time_t
Description: The NuttX time_t is type uint32_t. I think this is consistent
with all standards and with normal usage of time_t. However,
according to Wikipedia, time_t is usually implemented as a
signed 32-bit value.
Status: Open
Priority: Very low unless there is some compelling issue that I do not
know about.
Description: The definition of environ in stdlib.h is bogus and will not
work as it should. This is because the underlying
representation of the environment is not an array of pointers.
Description: Need some minimal termios support... at a minimum, enough to
switch between raw and "normal" modes to support behavior like
that needed for readline().
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UPDATE: There is growing functionality in libc/termios/ and in the
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ioctl methods of several MCU serial drivers (stm32, lpc43, lpc17,
pic32). However, as phrased, this bug cannot yet be closed since
this "growing functionality" does not address all termios.h
functionality and not all serial drivers support termios.
Description: There is an issue with the way that getopt() handles errors that
return '?'.
1. Does getopt() reset its global variables after returning '?' so
that it can be re-used? That would be required to support where
the caller terminates parsing before reaching the last parameter.
2. Or is the client expected to continue parsing after getopt()
returns '?' and parse until the final parameter?
The current getopt() implementation only supports #2.
Status: Open
Priority: Low
Title: CONCURRENT STREAM READ/WRITE
Description: NuttX only supports a single file pointer so reads and writes
must be from the same position. This prohibits implementation
of behavior like that required for fopen() with the "a+" mode.
According to the fopen man page:
"a+ Open for reading and appending (writing at end of file).
The file is created if it does not exist. The initial file
position for reading is at the beginning of the file, but
output is always appended to the end of the file."
At present, the single NuttX file pointer is positioned to the
end of the file for both reading and writing.
Status: Open
Priority: Medium. This kind of operation is probably not very common in
deeply embedded systems but is required by standards.
Title: DIVIDE BY ZERO
Description: This is bug 3468949 on the SourceForge website (submitted by
Philipp Klaus Krause):
"lib_strtod.c does contain divisions by zero in lines 70 and 96.
AFAIK, unlike for Java, division by zero is not a reliable way to
get infinity in C. AFAIK compilers are allowed e.g. give a compile-
time error, and some, such as sdcc, do. AFAIK, C implementations
are not even required to support infinity. In C99 the macro isinf()
could replace the first use of division by zero. Unfortunately, the
macro INFINITY from math.h probably can't replace the second division
by zero, since it will result in a compile-time diagnostic, if the
implementation does not support infinity."
Status: Open
Priority:
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Description: This implementation of dtoa in libc/stdio is old and will not
work with some newer compilers. See
http://patrakov.blogspot.com/2009/03/dont-use-old-dtoac.html
Status: Open
Priority: ??
Title: FLOATING POINT FORMATS
Description: Only the %f floating point format is supported. Others are accepted
but treated like %f.
Status: Open
Priority: Medium (this might important to someone).
Title: FLOATING POINT PRECISION
Description: A fieldwidth and precision is required with the %f format. If %f
is used with no format, than floating numbers will be printed with
a precision of 0 (effectively presented as integers).
Status: Open
Priority: Medium (this might important to someone).
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Title: LIBM INACCURACIES
Description: "..if you are writing something like robot control or
inertial navigation system for aircraft, I have found
that using the toolchain libmath is only safe option.
I ported some code for converting quaternions to Euler
angles to NuttX for my project and only got it working
after switching to newlib math library.
"NuttX does not fully implement IEC 60559 floating point
from C99 (sections marked [MX] in OpenGroup specs) so if
your code assumes that some function, say pow(), actually
behaves right for all the twenty or so odd corner cases
that the standards committees have recently specified,
you might get surprises. I'd expect pow(0.0, 1.0) to
return 0.0 (as zero raised to any positive power is
well-defined in mathematics) but I get +Inf.
"NuttX atan2(-0.0, -1.0) returns +M_PI instead of correct
-M_PI. If we expect [MX] functionality, then atan2(Inf, Inf)
should return M_PI/4, instead NuttX gives NaN.
"asin(2.0) does not set domain error or return NaN. In fact
it does not return at all as the loop in it does not
converge, hanging your app.
"There are likely many other issues like these as the Rhombus
OS code has not been tested or used that much. Sorry for not
providing patches, but we found it easier just to switch the
math library."
Ref: https://groups.yahoo.com/neo/groups/nuttx/conversations/messages/7805
UPDATE: 2015-09-01: A fix for the noted problems with asin()
has been applied.
Priority: Low for casual users but clearly high if you need care about
these incorrect corner case behaviors in the math libraries.
o File system / Generic drivers (fs/, drivers/)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
NOTE: The NXFFS file system has its own TODO list at nuttx/fs/nxffs/README.txt
Title: CHMOD(), TRUNCATE(), AND FSTAT()
Description: Implement chmod(), truncate(), and fstat().
Description: At present, the CAN driver does not support the poll() method.
Status: Open
Priority: Low
Description: The ROMFS file system does not verify checksums on either
volume header on on the individual files.
Status: Open
Priority: Low. I have mixed feelings about if NuttX should pay a
performance penalty for better data integrity.
Title: SPI-BASED SD MULTIPLE BLOCK TRANSFERS
Description: The simple SPI based MMCS/SD driver in fs/mmcsd does not
yet handle multiple block transfers.
Status: Open
Priority: Medium-Low
Title: SDIO-BASED SD READ-AHEAD/WRITE BUFFERING INCOMPLETE
Description: The drivers/mmcsd/mmcsd_sdio.c driver has hooks in place to
support read-ahead buffering and write buffering, but the logic
is incomplete and untested.
Status: Open
Priority: Low
Description: All drivers that support the poll method should also report
Status: Open
Priority: Medium-Low
Description: When I enable CONFIG_RAMLOG_CONSOLE, the system does not come up
properly (using configuration stm3240g-eval/nsh2). The problem
may be an assertion that is occurring before we have a console.
Title: UNIFIED DESCRIPTOR REPRESENTATION
Descripton: There are two separate ranges of descriptors for file and
socket descriptors: if a descriptor is in one range then it is
recognized as a file descriptor; if it is in another range
then it is recognized as a socket descriptor. These separate
descriptor ranges can cause problems, for example, they makes
dup'ing descriptors with dup2() problematic. The two groups
of descriptors are really indices into two separate tables:
On an array of file structures and the other an array of
socket structures. There really should be one array that
is a union of file and socket descriptors. Then socket and
Status: Open
Priority: Low
Title: DUPLICATE FAT FILE NAMES
Description: "The NSH and POSIX API interpretations about sensitivity or
insensitivity to upper/lowercase file names seem to be not
consistent in our usage - which can result in creating two
directories with the same name..."
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Example using NSH:
nsh> echo "Test1" >/tmp/AtEsT.tXt
nsh> echo "Test2" >/tmp/aTeSt.TxT
nsh> ls /tmp
/tmp:
AtEsT.tXt
aTeSt.TxT
nsh> cat /tmp/aTeSt.TxT
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nsh> cat /tmp/AtEsT.tXt
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Title: FAT LONG FILENAME COMPATIBILTY
Description: Recently there have been reports that file with long file
names created by NuttX don't have long file names when viewed
on Windows. The long file name support has been around for a
long time and I don't ever having seen this before so I am
suspecting that some evil has crept in.
Status: Open
Priority: Medium
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Title: MISSING FILES IN NSH 'LS' OF A DIRECTORY
Description: I have seen cases where (1) long file names are enabled,
but (2) a short file name is created like:
nsh> echo "This is another thest" >/mnt/sdcard/another.txt
But then on subsequent 'ls' operations, the file does not appear:
nsh> ls -l /mnt/sdcard
I have determined that the problem is because, for some as-
of-yet-unkown reason the short file name is treated as a long
file name. The name then fails the long filename checksum
test and is skipped.
readdir() (and fat_readdir()) is the logic underlying the
failure and the problem appears to be something unique to the
fat_readdir() implementation. Why? Because the file is
visible when you put the SD card on a PC and because this
works fine:
nsh> ls -l /mnt/sdcard/another.txt
The failure does not happen on all short file names. I do
not understand the pattern. But I have not had the opportunity
to dig into this deeply.
Status: Open
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Priority: Perhaps not a problem??? I have analyzed this problem and
I am not sure what to do about it. I am suspected that a
fat filesystem was used with a version of NuttX that does
not support long file name entries. Here is the failure
scenario:
1) A file with a long file name is created under Windows.
2) Then the file is deleted. I am not sure if Windows or
NuttX deleted the file, but the resulting directory
content is not compatible with NuttX with long file
name support.
The file deletion left the full sequence of long
file name entries intact but apparently delete only
the following short file name entry. I am thinking
that this might have happened because a version of NuttX
with only short file name support was used to delete
the file.
3) When a new file with a short file name was created, it
re-used the short file name entry that was previously
deleted. This makes the new short file name entry
look like a part of the long file name.
4) When comparing the checksum in the long file name
entry with the checksum of the short file name, the
checksum fails and the entire directlry sequence is
ignored by readder() logic. This the file does not
appear in the 'ls'.
See also the NxWidgets TODO list file for related issues.
Description: Testing of all APIs is not complete. See
http://nuttx.sourceforge.net/NXGraphicsSubsystem.html#testcoverage
Status: Open
Priority: Medium
Title: ITALIC FONTS / NEGATIVE FONT OFFSETS
Description: Font metric structure (in include/nuttx/nx/nxfont.h) should allow
negative X offsets. Negative x-offsets are necessary for certain
glyphs (and is very common in italic fonts).
For example Eth, icircumflex, idieresis, and oslash should have
offset=1 in the 40x49b font (these missing negative offsets are
NOTE'ed in the font header files).
Status: Open. The problem is that the x-offset is an unsigned bitfield
in the current structure.
Priority: Low.
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Title: RAW WINDOW AUTORAISE
Description: Auto-raise only applies to NXTK windows. Shouldn't it also apply
to raw windows as well?
Status: Open
Priority: Low
Title: AUTO-RAISE DISABLED
Description: Auto-raise is currently disabled in NX multi-server mode. The
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reason is complex:
- Most touchscreen controls send touch data a high rates
- In multi-server mode, touch events get queued in a message
queue.
- The logic that receives the messages performs the auto-raise.
But it can do stupid things after the first auto-raise as
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I am thinking that auto-raise ought to be removed from NuttX
and moved out into a graphics layer (like NxWM) that knows
more about the appropriate context to do the autoraise.
Status: Open
Priority: Medium low
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Title: IMPROVED NxTERM FONT CACHING
Description: Now each NxTerm instance has its own private font cache
whose size is determined by CONFIG_NXTERM_MXCHARS. If there
are multiple NxTerm instances using the same font, each will
have a separate font cache. This is inefficient and wasteful
of memory: Each NxTerm instance should share a common font
cache.
Status: Open
Priority: Medium. Not important for day-to-day testing but would be
a critical improvement if NxTerm were to be used in a
product.
Title: NxTERM VT100 SUPPORT
Description: If the NxTerm will be used with the Emacs-like command line
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editor (CLE), then it will need to support VT100 cursor control
commands.
Status: Open
Priority: Low, the need has not yet arisen.
Title: PER-WINDOW FRAMEBUFFERS
Description: One of the most awkard things to handle in the NX windowing
system is the re-draw callback. This is difficult because it
requires ad hoc, custom logic to be able to do the redrawing
in most cases.
One solution would be to provide a per-window framebuffer.
All rending would be performed into the per-window framebuffer
and the rended bits would be copied the LCD or framebuffer
device memory on demand when the redraw is required.
This would (a) greatly simplify the graphics interface, (b)
greatly improve redraw performance, and (c) enable a more
generic use of the windowing. The downside would be a large
usage of memory to hold all of the framebuffers, one for each
window.
Status: Open
Priority: Low, of mostly strategic value.
Title: VERTICAL ANTI-ALIASING
Description: Anti-aliasing is implemented along the horizontal raster line
with fractional pixels at the ends of each line. There is no
accounting for fractional pixels in the vertical direction.
As a result lines closer to vertical receive better anti-
aliasing than lines closer to horizontal.
Status: Open
Priority: Low, not a serious issue but worth noting. There is no plan
to change this behavior.
Title: P-CODES IN MEMORY UNTESTED
Description: Need APIs to verify execution of P-Code from memory buffer.
Status: Open
Title: SMALLER LOADER AND OBJECT FORMAT
Description: Loader and object format may be too large for some small
memory systems. Consider ways to reduce memory footprint.
Title: PDBG
Description: Move the the pascal p-code debugger into the NuttX apps/ tree
where it can be used from the NSH command line.
Status: Open
Priority: Low
Title: WINDOWS DEPENDENCY GENERATION
Description: Dependency generation is currently disabled when a Windows native
toolchain is used in a POSIX-like environment (like Cygwin). The
issue is that the Windows tool generates dependencies use Windows
path formatting and this fails with the dependency file (Make.dep)
is include). Perhaps the only issue is that all of the Windows
dependencies needed to be quoted in the Make.dep files.
Status: Open
Priority: Low -- unless some dependency-related build issues is discovered.
Title: MAKE EXPORT LIMITATIONS
Description: The top-level Makefile 'export' target that will bundle up all of the
NuttX libraries, header files, and the startup object into an export-able
tarball. This target uses the tools/mkexport.sh script. Issues:
1. This script assumes the host archiver ar may not be appropriate for
non-GCC toolchains
2. For the kernel build, the user libraries should be built into some
libuser.a. The list of user libraries would have to accepted with
some new argument, perhaps -u.
Status: Open
Priority: Low.
o Linux/Cywgin simulation (arch/sim)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Title: SIMULATOR NETWORKING SUPPORT
Description: I never did get networking to work on the sim Linux target. On Linux,
it tries to use the tap device (/dev/net/tun) to emulate an Ethernet
NIC, but I never got it correctly integrated with the NuttX networking.
NOTE: On Cygwin, the build uses the Cygwin WPCAP library and is, at
least, partially functional (it has never been rigorously tested).
Status: Open
Priority: Low (unless you want to test networking features on the simulation).
Title: SIMULATOR HAS NO INTERRUPTS (NON-PREMPTIBLE)
Description: The current simulator implementation is has no interrupts and, hence,
is non-preemptible. Also, without simulated interrupt, there can
be no high-fidelity simulated device drivers.
Currently, all timing and serial input is simulated in the IDLE loop:
When nothing is going on in the simulation, the IDLE loop runs and
fakes timer and UART events.
Status: Open
Priority: Low, unless there is a need for developing a higher fidelity simulation
I have been thinking about how to implement simulated interrupts in
the simulation. I think a solution would work like this:
http://www.nuttx.org/doku.php?id=wiki:nxinternal:simulator
Title: ROUND-ROBIN SCHEDULING IN THE SIMULATOR
Description: Since the simulation is not pre-emptible, you can't use round-robin
scheduling (no time slicing). Currently, the timer interrupts are
"faked" during IDLE loop processing and, as a result, there is no
task pre-emption because there are no asynchronous events. This could
probably be fixed if the "timer interrupt" were driver by Linux
signals. NOTE: You would also have to implement irqsave() and
irqrestore() to block and (conditionally) unblock the signal.
Status: Open
Priority: Low
Title: IMPROVED ARM INTERRUPT HANDLING
Description: ARM interrupt handling performance could be improved in some
ways. One easy way is to use a pointer to the context save
This approach is already implemented for the ARM Cortex-M0,
Cortex-M3, Cortex-M4, and Cortex-A5 families. But still needs
to be back-ported to the ARM7 and ARM9 (which are nearly
identical to the Cortex-A5 in this regard). The change is
*very* simple for this architecture, but not implemented.
Status: Open. But complete on all ARM platforms except ARM7 and ARM9.
Priority: Low.
Title: IMPROVED ARM INTERRUPT HANDLING
Description: The ARM and Cortex-M3 interrupt handlers restores all registers
upon return. This could be improved as well: If there is no
context switch, then the static registers need not be restored
because they will not be modified by the called C code.
(see arch/sh/src/sh1/sh1_vector.S for example)
Status: Open
Priority: Low
Title: CORTEX-M3 STACK OVERFLOW
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Description: There is bit bit logic in up_fullcontextrestore() that executes on
return from interrupts (and other context switches) that looks like:
ldr r1, [r0, #(4*REG_CPSR)] /* Fetch the stored CPSR value */
msr cpsr, r1 /* Set the CPSR */
/* Now recover r0 and r1 */
ldr r0, [sp]
ldr r1, [sp, #4]
add sp, sp, #(2*4)
/* Then return to the address at the stop of the stack,
* destroying the stack frame
*/
ldr pc, [sp], #4
Under conditions of excessively high interrupt conditions, many
nested interrupts can occur just after the 'msr cpsr' instruction.
At that time, there are 4 bytes on the stack and, with each
interrupt, the stack pointer may increment and possibly overflow.
This can happen only under conditions of continuous interrupts.
See this email thread: https://groups.yahoo.com/neo/groups/nuttx/conversations/messages/1261
On suggested change is:
ldr r1, [r0, #(4*REG_CPSR)] /* Fetch the stored CPSR value */
msr spsr_cxsf, r1 /* Set the CPSR */
ldmia r0, {r0-r15}^
But this has not been proven to be a solution.
UPDATE: Other ARM architectures have a similer issue.
Priority: Low. The conditions of continuous interrupts is really the problem.
If your design needs continuous interrupts like this, please try
the above change and, please, submit a patch with the working fix.
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Title: STACK ALIGNMENT IN INTERRUPT HANDLERS
Description: The EABI standard requires that the stack always have a 32-byte
alignment. There is no guarantee at present that the stack will be
so aligned in an interrupt handler. Therefore, I would expect some
issues if, for example, floating point or perhaps long long operations
were performed in an interrupt handler.
This issue exists for ARM7, ARM9, and Cortex-M0 but has been
addressed for the Cortex-M3/4/7 and Cortex-A5/8. The fix
is really simple but cannot be incorporated without some
substantial testing. For ARM, the fix is the following logic
arround each call into C code from assembly:
mov r4, sp /* Save the SP in a preserved register */
bl cfunction /* Call the C function */
mov sp, r4 /* Restore the possibly unaligned stack pointer */
This same issue applies to the interrupt stack which is, I think
improperly aligned in almost all cases (except Cortex-A5).
Status: Open
Priority: Low for me because I never do floating point operations in
interrupt handlers.
Title: IMPROVED TASK START-UP AND SYSCALL RETURN
Description: Couldn't up_start_task and up_start_pthread syscalls be
eliminated. Wouldn't this work to get us from kernel-
to user-mode with a system trap:
lda r13, #address
str rn, [r13]
msr spsr_SVC, rm
ld r13,{r15}^
Would also need to set r13_USER and r14_USER. For new
SYS_context_switch... couldn't we do he same thing?
Also... System calls use traps to get from user- to kernel-
mode to perform OS services. That is necessary to get from
user- to kernel-mode. But then another trap is used to get
from kernel- back to user-mode. It seems like this second
trap should be unnecessary. We should be able to do the
same kind of logic to do this.
Status: Open
Priority: Low-ish, but a good opportunity for performance improvement.
Title: UNVERIFIED THTTPD FEATURES
Description: Not all THTTPD features/options have been verified. In particular, there is no
test case of a CGI program receiving POST input. Only the configuration of
Status: Open
Priority: Medium
Description: If the network is enabled, but THTTPD is not configured, it spews out lots
of pointless warnings. This is kind of annoying and unprofessional; needs to
be fixed someday.
Status: Open. An annoyance, but not a real problem.
Priority: Low
Title: DHCPD ACCESSES KERNEL PRIVATE INTERFACE
Description: arp_update() is referenced outside of nuttx/net. It is used in
in the netutils/ DHCPD logic to set entries in the ARP table.
That is violation of the separation of kernel and OS
functionality. As a consequence, dhcpd will not work with the
NuttX kernel built.
This direct OS call needs to be replaced with a network ioctl()
call.
Status: Open
Priority: Medium. Important for full functionality with kernel build.
Title: NETWORK MONITOR NOT GENERALLY AVAILABLE
Description: The NSH network management logic has general applicability
but is currently useful only because it is embedded in the NSH
module. It should be moved to apps/system or, better,
apps/netutils.
Status: Open
Priority: Low
o NuttShell (NSH) (apps/nshlib)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Title: IFCONFIG AND MULTIPLE NETWORK INTERFACES
Descripton: The ifconfig command will not behave correctly if an interface
is provided and there are multiple interfaces. It should only
show status for the single interface on the command line; it will
still show status for all interfaces.
Status: Open
Priority: Low
Gregory Nutt
committed
Description: Add an ARP command so that we can see and modify the contents of
the ARP table.
Status: Open
Priority: Low (enhancement)
Title: ARPPING COMMAND
Description: Add an arping command
Status: Open
Priority: Low (enhancement)
o System libraries apps/system (apps/system)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Title: READLINE IMPLEMENTATION
Description: readline implementation does not use C-buffered I/O, but rather
talks to serial driver directly via read(). It includes VT-100
specific editing commands. A more generic readline() should be
implemented using termios' tcsetattr() to put the serial driver
into a "raw" mode.
Status: Open
Priority: Low (unless you are using mixed C-buffered I/O with readline and
fgetc, for example).
o Other Applications & Tests (apps/examples/)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Title: EXAMPLES/PIPE ON CYGWIN
Description: The redirection test (part of examples/pipe) terminates
incorrectly on the Cywgin-based simulation platform (but works
fine on the Linux-based simulation platform).
Status: Open
Priority: Low
Title: EXAMPLES/SENDMAIL UNTESTED
Description: examples/sendmail is untested on the target (it has been tested
on the host, but not on the target).
Title: EXAMPLES/NX FONT CACHING
Description: The font caching logic in examples/nx is incomplete. Fonts are
added to the cache, but never removed. When the cache is full
it stops rendering. This is not a problem for the examples/nx
code because it uses so few fonts, but if the logic were
leveraged for more general purposes, it would be a problem.
Update: see examples/nxtext for some improved font cache handling.
Status: Open
Priority: Low. This is not really a problem because examples/nx works
fine with its bogus font caching.
Title: EXAMPLES/NXTEXT ARTIFACTS
Description: examples/nxtext. Artifacts when the pop-up window is opened.
There are some artifacts that appear in the upper left hand
corner. These seems to be related to window creation. At
tiny artifact would not be surprising (the initial window
should like at (0,0) and be of size (1,1)), but sometimes
the artifact is larger.
Status: Open
Priority: Medium.