Hello, this set of patches fixes PPP. Basically the current implementation in libbsd can't work with console drivers that can't buffer a lot of characters. The pppstart() function just assumes that the low level console write can send an arbitrary number of characters without checking how many characters are actually send.
In the extreme case of the ATSAM interfaces (only one character can be send at once) it's not even possible to establish a PPP connection with that. For UARTS that have some FIFO establishing might work but bigger packets won't go through. I opened tickets for 6 and 5 here: https://devel.rtems.org/ticket/4493 https://devel.rtems.org/ticket/4494 I would like to apply the patches to both branches (5 and 6). The solution I implemented in this patch set is the following: PPP output processing is done in the line discipline function l_start (or rather the function where l_start points to: pppstart). Our device writes don't return how many characters have been sent. Instead, that feedback is given via rtems_termios_dequeue(). Luckily that's the function that calls the l_start function. The RTEMS patch for termios extends the l_start function so that it gets the number of characters as a second argument. This extension shouldn't be a problem for existing code. In the worst case it will trigger a warning that the function doesn't match the pointer type. But in the linked code, that additional argument will just be ignored. The libbsd patch extends the pppstart function so that it then handles that new information. Patches belonging to this set: * [PATCH rtems 1/2] bsps/atsam: Improve UART / USART tx performance * [PATCH rtems 2/2] termios: Pass number of sent chars to l_start * [PATCH rtems-libbsd] ppp: Fix transmitting data Best regards Christian _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
