cc other dear
I need your help! I am looking forward your reply
Xiaoming Fu
At 2022-03-16 19:07:01, "付小明" <fxm16899@163.com> wrote:
the function relation isserial_ioport_write(serial.c) -> serial_update_parameters(serial.c) -> qemu_chr_fe_ioctl(serial.c) -> tty_serial_ioctl(char-serial.c) -> tty_serial_init(char-serial.c)in tty_serial_init: tty.c_cflag &= ~(CSIZE | PARENB | PARODD | CRTSCTS | CSTOPB); is set no hardware flow control(-crtscts)tty.c_cflag |= CRTSCTS is set hardware fow control(crtscts)
2、the app in the guest set the speed, parity,data_bits,stop_bits, qemu can get them by the function serial_update_parameters. But qemu can not get the hardware flow control of the guest set。3、I find some knowledge. Hardware flow control is RTS/CTS . We can see MCR.So I try code like this :
if ((s->mcr & 0x02) && (s->mcr & 0x01) && ((~(s->msr)) & 0x10)) {
up_crtscts = 1;
} else {
up_crtscts = 0;
}
But RTS is no right. Because the RTS is enable when set hardware flow control and not set hardware flow control .This is may a qemu bugI think the RTS is enable when set hardware flow control ; the RTS is not enable when not set hardware flow control.I need your help! I am looking forward your reply!在 2022-03-16 18:32:59，"Dr. David Alan Gilbert" <dgilbert@redhat.com> 写道： >* 付小明 (fxm16899@163.com) wrote: >> hi all >> information >> -chardev tty,id=charserial0,path=/dev/ttyS0 -device pci-serial,chardev=charserial0,id=serial0,bus=pci.0,addr=0x17 -add-fd set=5,fd=28 -chardev tty,id=charserial1,path=/dev/ttyS1 -device pci-serial,chardev=charserial1,id=serial1,bus=pci.0,addr=0x18 -add-fd set=6,fd=29 -chardev tty,id=charserial2,path=/dev/ttyS2 -device pci-serial,chardev=charserial2,id=serial2,bus=pci.0,addr=0x19 -add-fd set=7,fd=30 -chardev tty,id=charserial3,path=/dev/ttyS3 -device pci-serial,chardev=charserial3,id=serial3,bus=pci.0,addr=0x1a > >Hi, > It's a while since I tried it; I think I would try adding debug to >see if char-serial.c tty_serial_ioctl is called. > >Dave > >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> At 2022-03-16 14:38:47, "付小明" <fxm16899@163.com> wrote: >> >> >> >> >> HI ,ALL >> Nice to meet you! I need your help. I find a bug in qemu. qemu not support serial hardware flow control >> 1、Problem: the machine's guest is windows, the machine's host is centos. The qemu emulation pci-serial. >> A printer （model is BTP-2001cp）use the serial to print. The machine connect the printer by serial port. >> The data printed by the printer is missing some data.You can see picture 1 is lost some data, picture 2 is normal.Because the printer need hardware flow control. >> This is a bug： >> the machine's guest is windows, the machine's host is centos. The qemu emulation pci-serial. >> A printer （model is BTP-2001cp）use the serial to print. The machine connect the printer by serial port. >> The data printed by the printer is missing some data >> because qemu not support serial hardware flow control。 >> 2、Problem: the machine's guest is linux, the machine's host is centos.qemu not support serial hardware flow control >> in the guest , use the serial hardware flow control by minicom. I find the guest serial stty -F /dev/ttyS0 -a is crtscts. But host the serial stty -F /dev/ttyS0 -a is -crtscts. >> >> >> I need your help! I am looking forward your reply >> >> >> >> >> Xiaoming Fu >> >> >> -------- Forwarding messages -------- >> From: "付小明" <fxm16899@163.com> >> Date: 2022-03-15 10:11:11 >> To: "Peter Maydell" <peter.maydell@linaro.org> >> Cc: "QEMU Developers" <qemu-devel@nongnu.org> >> Subject: Re:Re: set qemu support serial crtscts >> >> Hi， Peter and all developers >> Yes， I need to describe it clearly. >> 1、I want make the qemu serial support crtscts >> 2、Problem: the machine's guest is windows, the machine's host is centos. The qemu emulation pci-serial. >> A printer （model is BTP-2001cp）use the serial to print. The machine connect the printer by serial port. >> The data printed by the printer is missing some data.You can see picture 1 is lost some data, picture 2 is normal. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> At 2021-04-14 21:24:20, "Peter Maydell" <peter.maydell@linaro.org> wrote: >> >On Wed, 14 Apr 2021 at 14:18, 付小明 <fxm16899@163.com> wrote: >> >> >> >> HI, I have find qemu serial not support crtscts. This result some >> >> machine not communication, because this machine need crtscts >> > >> >Could you provide more detail, please? For a bug report it >> >is useful to know: >> > * what you were trying to do >> > * what happened >> > * what you expected to happen >> > * full details like the QEMU command line >> > * what guest software you were running >> > >> >Ideally, the report should have everything we need to be >> >able to reproduce the problem ourselves. >> > >> >thanks >> >-- PMM >> >> >> >> >> >> >> >> >> >> >> >> > > > >-- >Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
