On Tuesday 10 September 2013 12:26:32 you wrote: > Hi, I could really need some help to get the second application uart working > on my imx23 based board. > > I can use GDB to debug the kernel but I don't really know where to start, > maybe something is broken in drivers/tty/serial/mxs-auart.c. Hopefully > somebody could give me a hint what to do. > OK, receiving works, below you can see that I've received "Hello" one char at a time. > [chris@thinkpad linux-stable]$ arm-none-eabi-gdb vmlinux > GNU gdb (GNU Tools for ARM Embedded Processors) 7.4.1.20130312-cvs > Copyright (C) 2012 Free Software Foundation, Inc. > License GPLv3+: GNU GPL version 3 or later > <http://gnu.org/licenses/gpl.html> > This is free software: you are free to change and redistribute it. > There is NO WARRANTY, to the extent permitted by law. Type "show copying" > and "show warranty" for details. > This GDB was configured as "--host=i686-linux-gnu --target=arm-none-eabi". > For bug reporting instructions, please see: > <http://www.gnu.org/software/gdb/bugs/>... > Reading symbols from > /home/chris/local/OLinuXino/imx23-olinuxino/kernel/linux-stable/vmlinux...d > one. (gdb) c > The program is not being run. > (gdb) target remote :3333 > Remote debugging using :3333 > ?? () at arch/arm/kernel/entry-armv.S:1132 > 1132 W(b) vector_rst > (gdb) c > Continuing. > WARNING! The target is already running. All changes GDB did to registers > will be discarded! Waiting for target to halt. ^C > Program received signal SIGINT, Interrupt. > 0xc0814728 in start_kernel () at init/main.c:480 > 480 while(wait_for_debugger); > (gdb) break mxs_auart_rx_char > Function "mxs_auart_rx_char" not defined. > Make breakpoint pending on future shared library load? (y or [n]) n > (gdb) break drivers/tty/serial/mxs-auart.c:mxs_auart_rx_char > Function "mxs_auart_rx_char" not defined in > "drivers/tty/serial/mxs-auart.c". > Make breakpoint pending on future shared library load? (y or [n]) n > (gdb) break drivers/tty/serial/mxs-auart.c:703 > Breakpoint 1 at 0xc02d7be0: file drivers/tty/serial/mxs-auart.c, line 703. > (gdb) set var wait_for_debugger=0 > (gdb) c > Continuing. > > Breakpoint 1, mxs_auart_irq_handle (irq=<optimized out>, context=0xc3a27a00) > at drivers/tty/serial/mxs-auart.c:704 704 istat &= > ~(AUART_INTR_RTIS | AUART_INTR_RXIS); (gdb) s > 707 if (istat & AUART_INTR_TXIS) { > (gdb) s > 708 mxs_auart_tx_chars(s); > (gdb) s > mxs_auart_tx_chars (s=s@entry=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:249 249 if > (auart_dma_enabled(s)) { > (gdb) s > auart_dma_enabled (s=<optimized out>) at drivers/tty/serial/mxs-auart.c:184 > 184 return s->flags & MXS_AUART_DMA_ENABLED; > (gdb) s > mxs_auart_tx_chars (s=s@entry=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:246 246 { > (gdb) delete breakpoints 1 > (gdb) break drivers/tty/serial/mxs-auart.c:320 > Breakpoint 2 at 0xc02d7c4c: file drivers/tty/serial/mxs-auart.c, line 320. > (gdb) c > Continuing. > > Breakpoint 2, mxs_auart_rx_chars (s=<optimized out>) at > drivers/tty/serial/mxs-auart.c:367 367 > mxs_auart_rx_char(s); > (gdb) delete breakpoints > Delete all breakpoints? (y or n) y > (gdb) break drivers/tty/serial/mxs-auart.c:321 > Breakpoint 3 at 0xc02d7c54: file drivers/tty/serial/mxs-auart.c, line 321. > (gdb) c > Continuing. > > Breakpoint 3, mxs_auart_rx_char (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:321 321 stat = > readl(s->port.membase + AUART_STAT); > (gdb) list > 316 int flag; > 317 u32 stat; > 318 u8 c; > 319 > 320 c = readl(s->port.membase + AUART_DATA); > 321 stat = readl(s->port.membase + AUART_STAT); > 322 > 323 flag = TTY_NORMAL; > 324 s->port.icount.rx++; > 325 > (gdb) p c > $3 = 72 'H' > (gdb) c > Continuing. > > Breakpoint 3, mxs_auart_rx_char (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:321 321 stat = > readl(s->port.membase + AUART_STAT); > (gdb) p c > $4 = 101 'e' > (gdb) c > Continuing. > > Breakpoint 3, mxs_auart_rx_char (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:321 321 stat = > readl(s->port.membase + AUART_STAT); > (gdb) p c > $5 = 108 'l' > (gdb) c > Continuing. > > Breakpoint 3, mxs_auart_rx_char (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:321 321 stat = > readl(s->port.membase + AUART_STAT); > (gdb) p c > $6 = 108 'l' > (gdb) c > Continuing. > > Breakpoint 3, mxs_auart_rx_char (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:321 321 stat = > readl(s->port.membase + AUART_STAT); > (gdb) p c > $7 = 111 'o' > (gdb) All my sent characters and the login prompt (\r\r\nArch Linux 3.11.0- next-20130910-dirty (ttyAPP1)\r\n\r\nolinuxino login: ddHHe[AHelloWW) are in the tx buffer: > (gdb) delete breakpoints > Delete all breakpoints? (y or n) y > (gdb) break drivers/tty/serial/mxs-auart.c:285 > Breakpoint 5 at 0xc02d7308: file drivers/tty/serial/mxs-auart.c, line 285. > (gdb) c > Continuing. > > Breakpoint 5, mxs_auart_tx_chars (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:285 285 if > (s->port.x_char) { > (gdb) p s->port.x_char > $8 = 0 '\000' > (gdb) list > 280 } > 281 > 282 > 283 while (!(readl(s->port.membase + AUART_STAT) & > 284 AUART_STAT_TXFF)) { > 285 if (s->port.x_char) { > 286 s->port.icount.tx++; > 287 writel(s->port.x_char, > 288 s->port.membase + AUART_DATA); > 289 s->port.x_char = 0; > (gdb) break drivers/tty/serial/mxs-auart.c:294 > Breakpoint 6 at 0xc02d72c8: file drivers/tty/serial/mxs-auart.c, line 294. > (gdb) n > 292 if (!uart_circ_empty(xmit) && > !uart_tx_stopped(&s->port)) { (gdb) n > 293 s->port.icount.tx++; > (gdb) n > > Breakpoint 6, mxs_auart_tx_chars (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:294 294 > writel(xmit->buf[xmit->tail], > (gdb) p xmit->buf[xmit->tail] > $10 = 87 'W' > (gdb) p xmit->buf > $9 = 0xc29cb000 "\r\r\nArch Linux 3.11.0-next-20130910-dirty > (ttyAPP1)\r\n\r\nolinuxino login: ddHHe[AHelloWW" > (gdb) But I don't receive them: > (gdb) list > 289 s->port.x_char = 0; > 290 continue; > 291 } > 292 if (!uart_circ_empty(xmit) && > !uart_tx_stopped(&s->port)) { 293 > s->port.icount.tx++; > 294 writel(xmit->buf[xmit->tail], > 295 s->port.membase + AUART_DATA); > 296 xmit->tail = (xmit->tail + 1) & > (UART_XMIT_SIZE - 1); 297 } else > 298 break; > (gdb) n > 293 s->port.icount.tx++; > (gdb) n > 294 writel(xmit->buf[xmit->tail], > (gdb) n > 296 xmit->tail = (xmit->tail + 1) & > (UART_XMIT_SIZE - 1); (gdb) n > 283 while (!(readl(s->port.membase + AUART_STAT) & > (gdb) n > > Breakpoint 5, mxs_auart_tx_chars (s=0xc3a27a00) at > drivers/tty/serial/mxs-auart.c:285 285 if > (s->port.x_char) { > (gdb) n > 292 if (!uart_circ_empty(xmit) && > !uart_tx_stopped(&s->port)) { (gdb) n > 301 uart_write_wakeup(&s->port); > (gdb) n > 303 if (uart_circ_empty(&(s->port.state->xmit))) > (gdb) n > 304 writel(AUART_INTR_TXIEN, > (gdb) n > 303 if (uart_circ_empty(&(s->port.state->xmit))) > (gdb) n > 304 writel(AUART_INTR_TXIEN, > (gdb) n > 310 if (uart_tx_stopped(&s->port)) > (gdb) n > 312 } > (gdb) n > uart_start (tty=tty@entry=0xc3b90000) at > drivers/tty/serial/serial_core.c:105 > 105 spin_unlock_irqrestore(&port->lock, flags); > (gdb) c > Continuing. The line numbers are from next-20130910. Does somebody has an idea what could be broken? -- chris -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
