On 24.09.21 23:07, Marek Behún wrote:
From: Pali Rohár pali@kernel.org
The A38x platform supports more baudrates than just those defined by the Bn constants, and some of them are higher than the highest Bn baudrate (the highest is 4 MBd while A38x support 5.15 MBd).
On Linux, add support for arbitrary baudrates. (Since there is no standard POSIX API to specify arbitrary baudrate for a tty device, this change is Linux-specific.)
We need to use raw TCGETS2/TCSETS2 or TCGETS/TCSETS ioctls with the BOTHER flag in struct termios2/termios, defined in Linux headers <asm/ioctls.h> (included by <sys/ioctl.h>) and <asm/termbits.h>. Since these headers conflict with glibc's header file <termios.h>, it is not possible to use libc's termios functions and we need to reimplement them via ioctl() calls.
Note that the Bnnn constants from <termios.h> need not be compatible with Bnnn constants from <asm/termbits.h>.
Signed-off-by: Pali Rohár pali@kernel.org [ termios macros rewritten to static inline functions (for type control) and moved to tools/termios_linux.h ] Signed-off-by: Marek Behún marek.behun@nic.cz
Reviewed-by: Stefan Roese sr@denx.de
Thanks, Stefan
tools/kwboot.c | 16 +++- tools/termios_linux.h | 189 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 204 insertions(+), 1 deletion(-) create mode 100644 tools/termios_linux.h
diff --git a/tools/kwboot.c b/tools/kwboot.c index ba2fd10ff6..7ccab2993f 100644 --- a/tools/kwboot.c +++ b/tools/kwboot.c @@ -23,10 +23,15 @@ #include <errno.h> #include <unistd.h> #include <stdint.h> -#include <termios.h> #include <time.h> #include <sys/stat.h>
+#ifdef __linux__ +#include "termios_linux.h" +#else +#include <termios.h> +#endif
- /*
*/
- Marvell BootROM UART Sensing
@@ -554,7 +559,11 @@ kwboot_tty_baudrate_to_speed(int baudrate) return B50; #endif default: +#ifdef BOTHER
return BOTHER;+#else return B0; +#endif } }
@@ -575,6 +584,11 @@ kwboot_tty_change_baudrate(int fd, int baudrate) return -1; }
+#ifdef BOTHER
- if (speed == BOTHER)
tio.c_ospeed = tio.c_ispeed = baudrate;+#endif
- rc = cfsetospeed(&tio, speed); if (rc) return rc;
diff --git a/tools/termios_linux.h b/tools/termios_linux.h new file mode 100644 index 0000000000..d73989b625 --- /dev/null +++ b/tools/termios_linux.h @@ -0,0 +1,189 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*
- termios fuctions to support arbitrary baudrates (on Linux)
- Copyright (c) 2021 Pali Rohár pali@kernel.org
- Copyright (c) 2021 Marek Behún marek.behun@nic.cz
- */
+#ifndef _TERMIOS_LINUX_H_ +#define _TERMIOS_LINUX_H_
+/*
- We need to use raw TCGETS2/TCSETS2 or TCGETS/TCSETS ioctls with the BOTHER
- flag in struct termios2/termios, defined in Linux headers <asm/ioctls.h>
- (included by <sys/ioctl.h>) and <asm/termbits.h>. Since these headers
- conflict with glibc's header file <termios.h>, it is not possible to use
- libc's termios functions and we need to reimplement them via ioctl() calls.
- An arbitrary baudrate is supported when the macro BOTHER is defined. The
- baudrate value itself is then stored into the c_ospeed and c_ispeed members.
- If ioctls TCGETS2/TCSETS2 are defined and supported then these fields are
- present in struct termios2, otherwise these fields are present in struct
- termios.
- Note that the Bnnn constants from <termios.h> need not be compatible with Bnnn
- constants from <asm/termbits.h>.
- */
+#include <errno.h> +#include <sys/ioctl.h> +#include <sys/types.h> +#include <asm/termbits.h>
+#if defined(BOTHER) && defined(TCGETS2) +#define termios termios2 +#endif
+static inline int tcgetattr(int fd, struct termios *t) +{ +#if defined(BOTHER) && defined(TCGETS2)
- return ioctl(fd, TCGETS2, t);
+#else
- return ioctl(fd, TCGETS, t);
+#endif +}
+static inline int tcsetattr(int fd, int a, const struct termios *t) +{
- int cmd;
- switch (a) {
+#if defined(BOTHER) && defined(TCGETS2)
- case TCSANOW:
cmd = TCSETS2;break;- case TCSADRAIN:
cmd = TCSETSW2;break;- case TCSAFLUSH:
cmd = TCSETSF2;break;+#else
- case TCSANOW:
cmd = TCSETS;break;- case TCSADRAIN:
cmd = TCSETSW;break;- case TCSAFLUSH:
cmd = TCSETSF;break;+#endif
- default:
errno = EINVAL;return -1;- }
- return ioctl(fd, cmd, t);
+}
+static inline int tcdrain(int fd) +{
- return ioctl(fd, TCSBRK, 1);
+}
+static inline int tcflush(int fd, int q) +{
- return ioctl(fd, TCFLSH, q);
+}
+static inline int tcsendbreak(int fd, int d) +{
- return ioctl(fd, TCSBRK, d);
+}
+static inline int tcflow(int fd, int a) +{
- return ioctl(fd, TCXONC, a);
+}
+static inline pid_t tcgetsid(int fd) +{
- pid_t sid;
- if (ioctl(fd, TIOCGSID, &sid) < 0)
return (pid_t)-1;- return sid;
+}
+static inline speed_t cfgetospeed(const struct termios *t) +{
- return t->c_cflag & CBAUD;
+}
+static inline int cfsetospeed(struct termios *t, speed_t s) +{
- if (s & ~CBAUD) {
errno = EINVAL;return -1;- }
- t->c_cflag &= ~CBAUD;
- t->c_cflag |= s;
- return 0;
+}
+#ifdef IBSHIFT +static inline speed_t cfgetispeed(const struct termios *t) +{
- speed_t s = (t->c_cflag >> IBSHIFT) & CBAUD;
- if (s == B0)
return cfgetospeed(t);- else
return s;+}
+static inline int cfsetispeed(struct termios *t, speed_t s) +{
- if (s == 0)
s = B0;- if (s & ~CBAUD) {
errno = EINVAL;return -1;- }
- t->c_cflag &= ~(CBAUD << IBSHIFT);
- t->c_cflag |= s << IBSHIFT;
- return 0;
+} +#else /* !IBSHIFT */ +static inline speed_t cfgetispeed(const struct termios *t) +{
- return cfgetospeed(t);
+}
+static inline int cfsetispeed(struct termios *t, speed_t s) +{
- return cfsetospeed(t, s);
+} +#endif /* !IBSHIFT */
+static inline int cfsetspeed(struct termios *t, speed_t s) +{
- if (cfsetospeed(t, s))
return -1;+#ifdef IBSHIFT
- if (cfsetispeed(t, s))
return -1;+#endif
- return 0;
+}
+static void cfmakeraw(struct termios *t) +{
- t->c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR |
ICRNL | IXON);- t->c_oflag &= ~OPOST;
- t->c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
- t->c_cflag &= ~(CSIZE | PARENB);
- t->c_cflag |= CS8;
+}
+#endif /* _TERMIOS_LINUX_H_ */
Viele Grüße, Stefan