Some code paths in drivers/serial/serial.c load head and tail values
of receive and transmit circular buffers with interrupts enabled,
making it possible that the interrupt handler changes the value.
As noted in the code, this is safe as long as the load itself is atomic.
That is not true for 8bit architectures which fetch the 16-bit values
using two load instructions. If interrupt handler runs between those
two instructions and changes the value, the read returns corrupted data.
This patch introduces CONFIG_ARCH_LDST_16BIT_NOT_ATOMIC configuration
option which is automatically selected for AVR architecture. Based
on this option, head and tail values are reduced to 8-bit length
so the read remains atomic.
Patch was tested by building on rv-virt:nsh - disassembly of functions
from serial.c showed no difference which is correct as Risc-V does
not need to protect reads of these values. There should be no impact
for architectures that do not set the new configuration option.
It was also tested by by custom echo application running on AVR128DA28.
Signed-off-by: Kerogit <kr.git@kerogit.eu>
This commit add support to the serial_icounter_s struct used with
TIOCGICOUNT to report U[S]ART errors such as frame, parity, overrun,
etc.
Signed-off-by: Alan C. Assis <acassis@gmail.com>
Modify the kernel to use only atomic_xx and atomic64_xx interfaces,
avoiding the use of sizeof or typeof to determine the type of
atomic operations, thereby simplifying the kernel's atomic
interface operations.
Signed-off-by: zhangyuan29 <zhangyuan29@xiaomi.com>
1. Use critical_section to protect the fds array;
2. Use critical_section and sched lock to protect the poll notify, because
poll notify may cause context switch, delay the context swtich to
sched_unlock();
Signed-off-by: Bowen Wang <wangbowen6@xiaomi.com>
Most tools used for compliance and SBOM generation use SPDX identifiers
This change brings us a step closer to an easy SBOM generation.
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
add support for UART 16550 compatible PCI device.
For now we support qemu serial PCI devices and AX99100 based cards.
Signed-off-by: p-szafonimateusz <p-szafonimateusz@xiaomi.com>
prepare 16550 UART driver to support PCI:
- [breaking change] change argument of uart_ioctl() from `struct file *filep` to `FAR struct u16550_s *priv`
Also fix moxart_16550.c build related to this change
- [breaking change] change argument of uart_getreg() and uart_putreg from `uart_addrwidth_t base` to `FAR struct u16550_s *priv`
Also fix arch/x86/src/qemu/qemu_serial.c and arch/x86_64/src/intel64/intel64_serial.c related to this change
- [breaking change] change argument of uart_dmachan() from `uart_addrwidth_t base` to `FAR struct u16550_s *priv`
- move `struct u16550_s` to public header
- generalize UART_XXX_OFFSET so we can use it with any register increment
- make u16550_bind(), u16550_interrupt(), u16550_interrupt() public
- remove arch/or1k/src/common/or1k_uart.c and use common 16550 MIMO interfacve
- change irq type in `struct u16550_s` from uint8_t to int to match MSI API
Signed-off-by: p-szafonimateusz <p-szafonimateusz@xiaomi.com>
Summary:
1. Add nuttx/atomic.h in include
2. Use nuttx/atomic.h instead of stdatomic.h in the nuttx directory
Signed-off-by: chenrun1 <chenrun1@xiaomi.com>
stdint.h is needed in uart_16550.h for some types, e.g. uint32_t,
uintptr_t. Otherwise there will be building issue unless that stdint.h
is added before uart_16550.h by all files which needs uart_16550.h.
Signed-off-by: Jinliang Li <lijinliang1@lixiang.com>
we can use uart to debug nuttx,like debugger:
1. read/write memory
2. Use watchpoint,breakpoint,single step.
use up_debugpoint api
3. Ctrl+c to stop, continue, or single step.
hold uart send and receive
4. register a panic event, when crash or assert/panic, we use uart to
debug.
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
It uses the memory block as the serial communication medium, which can communicate between different processes or different CPUs
Using the following configuration, the cross-core communication rate of 200MHz cortex-M55 is about 461KB/s
RAM_UART_BUFSIZE=1024
RAM_UART_POLLING_INTERVAL=100
Signed-off-by: yinshengkai <yinshengkai@xiaomi.com>
Some UART Controllers (Synopsys DesignWare 8250) will trigger spurious interrupts when the Line Control Register (LCR) is set while the UART is busy. This patch provides the option (16550_WAIT_LCR) to wait for UART until it's not busy, before setting the LCR. (16550_WAIT_LCR is disabled by default)
This patch fixes the spurious UART interrupts for the upcoming port of NuttX to StarFive JH7110 SoC (with Synopsys DesignWare 8250 UART). [The patch is explained here](https://lupyuen.github.io/articles/plic#appendix-fix-the-spurious-uart-interrupts)
drivers/serial/uart_16550.c: If 16550_WAIT_LCR is enabled, wait until UART is not busy before setting LCR
include/nuttx/serial/uart_16550.h: Define the UART Status Register (USR) for checking if UART is busy
drivers/serial/Kconfig-16550: Added option 16550_WAIT_LCR to 16550 UART Config, disabled by default
if multiple threads are doing serial read/write at the same time,
the driver will only wake up one of the thread, which will cause
other threads fail to be woken up in time and cause blocking
Signed-off-by: chao an <anchao@xiaomi.com>
At present, the serial drivers qemu_serial.c and serial_pl011.c on the fvp-v8r and qemu platforms in arm64 are duplicated
and need to be merged. The plan is to place them under the drivers\serial directory to create a common code module,
so that both fvp-v8r and qemu can use the same code.
In the future, if new platforms use pl011 serial ports, they can also be directly reused
Signed-off-by: hujun5 <hujun5@xiaomi.com>
CONFIG_SERIAL_TERMIOS only decide whether to support c_cflag field since
many terminal application need the first three fields to work correctly.
For more information please reference:
https://www.mail-archive.com/dev@nuttx.apache.org/msg09321.html
before this change(olimexino-stm32:tiny):
text data bss dec hex filename
34884 328 1768 36980 9074 nuttx
after this change:
text data bss dec hex filename
35052 340 1768 37160 9128 nuttx
delta
text data bss dec hex filename
168 12 0 180 b4 nuttx
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
since the console is normally opened three time as stdin, stdout and
stderr and remove the dependence on STANDARD_SERIAL because other type
of serial drivers also support the poll through the same codebase.
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Ie68322c4647cc838b295491329969869d6ba310b
