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-rw-r--r--arch/mn10300/kernel/gdb-io-serial.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/gdb-io-serial.c b/arch/mn10300/kernel/gdb-io-serial.c
new file mode 100644
index 000000000000..9a6d4e8ebe73
--- /dev/null
+++ b/arch/mn10300/kernel/gdb-io-serial.c
@@ -0,0 +1,155 @@
+/* 16550 serial driver for gdbstub I/O
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/nmi.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/gdb-stub.h>
+#include <asm/exceptions.h>
+#include <asm/serial-regs.h>
+#include <asm/unit/serial.h>
+
+/*
+ * initialise the GDB stub
+ */
+void gdbstub_io_init(void)
+{
+ u16 tmp;
+
+ /* set up the serial port */
+ GDBPORT_SERIAL_LCR = UART_LCR_WLEN8; /* 1N8 */
+ GDBPORT_SERIAL_FCR = (UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR |
+ UART_FCR_CLEAR_XMIT);
+
+ FLOWCTL_CLEAR(DTR);
+ FLOWCTL_SET(RTS);
+
+ gdbstub_io_set_baud(115200);
+
+ /* we want to get serial receive interrupts */
+ XIRQxICR(GDBPORT_SERIAL_IRQ) = 0;
+ tmp = XIRQxICR(GDBPORT_SERIAL_IRQ);
+
+ IVAR0 = EXCEP_IRQ_LEVEL0;
+ set_intr_stub(EXCEP_IRQ_LEVEL0, gdbstub_io_rx_handler);
+
+ XIRQxICR(GDBPORT_SERIAL_IRQ) &= ~GxICR_REQUEST;
+ XIRQxICR(GDBPORT_SERIAL_IRQ) = GxICR_ENABLE | GxICR_LEVEL_0;
+ tmp = XIRQxICR(GDBPORT_SERIAL_IRQ);
+
+ GDBPORT_SERIAL_IER = UART_IER_RDI | UART_IER_RLSI;
+
+ /* permit level 0 IRQs to take place */
+ asm volatile(
+ " and %0,epsw \n"
+ " or %1,epsw \n"
+ :
+ : "i"(~EPSW_IM), "i"(EPSW_IE | EPSW_IM_1)
+ );
+}
+
+/*
+ * set up the GDB stub serial port baud rate timers
+ */
+void gdbstub_io_set_baud(unsigned baud)
+{
+ unsigned value;
+ u8 lcr;
+
+ value = 18432000 / 16 / baud;
+
+ lcr = GDBPORT_SERIAL_LCR;
+ GDBPORT_SERIAL_LCR |= UART_LCR_DLAB;
+ GDBPORT_SERIAL_DLL = value & 0xff;
+ GDBPORT_SERIAL_DLM = (value >> 8) & 0xff;
+ GDBPORT_SERIAL_LCR = lcr;
+}
+
+/*
+ * wait for a character to come from the debugger
+ */
+int gdbstub_io_rx_char(unsigned char *_ch, int nonblock)
+{
+ unsigned ix;
+ u8 ch, st;
+
+ *_ch = 0xff;
+
+ if (gdbstub_rx_unget) {
+ *_ch = gdbstub_rx_unget;
+ gdbstub_rx_unget = 0;
+ return 0;
+ }
+
+ try_again:
+ /* pull chars out of the buffer */
+ ix = gdbstub_rx_outp;
+ if (ix == gdbstub_rx_inp) {
+ if (nonblock)
+ return -EAGAIN;
+#ifdef CONFIG_MN10300_WD_TIMER
+ watchdog_alert_counter = 0;
+#endif /* CONFIG_MN10300_WD_TIMER */
+ goto try_again;
+ }
+
+ ch = gdbstub_rx_buffer[ix++];
+ st = gdbstub_rx_buffer[ix++];
+ gdbstub_rx_outp = ix & 0x00000fff;
+
+ if (st & UART_LSR_BI) {
+ gdbstub_proto("### GDB Rx Break Detected ###\n");
+ return -EINTR;
+ } else if (st & (UART_LSR_FE | UART_LSR_OE | UART_LSR_PE)) {
+ gdbstub_proto("### GDB Rx Error (st=%02x) ###\n", st);
+ return -EIO;
+ } else {
+ gdbstub_proto("### GDB Rx %02x (st=%02x) ###\n", ch, st);
+ *_ch = ch & 0x7f;
+ return 0;
+ }
+}
+
+/*
+ * send a character to the debugger
+ */
+void gdbstub_io_tx_char(unsigned char ch)
+{
+ FLOWCTL_SET(DTR);
+ LSR_WAIT_FOR(THRE);
+ /* FLOWCTL_WAIT_FOR(CTS); */
+
+ if (ch == 0x0a) {
+ GDBPORT_SERIAL_TX = 0x0d;
+ LSR_WAIT_FOR(THRE);
+ /* FLOWCTL_WAIT_FOR(CTS); */
+ }
+ GDBPORT_SERIAL_TX = ch;
+
+ FLOWCTL_CLEAR(DTR);
+}
+
+/*
+ * send a character to the debugger
+ */
+void gdbstub_io_tx_flush(void)
+{
+ LSR_WAIT_FOR(TEMT);
+ LSR_WAIT_FOR(THRE);
+ FLOWCTL_CLEAR(DTR);
+}