1 files changed, 216 insertions, 0 deletions

diff --git a/arch/frv/kernel/gdb-io.c b/arch/frv/kernel/gdb-io.c
new file mode 100644
index 000000000000..c997bccb9221
--- /dev/null
+++ b/arch/frv/kernel/gdb-io.c
@@ -0,0 +1,216 @@
+/* gdb-io.c: FR403 GDB stub I/O
+ *
+ * Copyright (C) 2003 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 License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, 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/serial_reg.h>
+
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/irc-regs.h>
+#include <asm/timer-regs.h>
+#include <asm/gdb-stub.h>
+#include "gdb-io.h"
+
+#ifdef CONFIG_GDBSTUB_UART0
+#define __UART(X) (*(volatile uint8_t *)(UART0_BASE + (UART_##X)))
+#define __UART_IRR_NMI 0xff0f0000
+#else /* CONFIG_GDBSTUB_UART1 */
+#define __UART(X) (*(volatile uint8_t *)(UART1_BASE + (UART_##X)))
+#define __UART_IRR_NMI 0xfff00000
+#endif
+
+#define LSR_WAIT_FOR(STATE)                     \
+do {                                            \
+        gdbstub_do_rx();                        \
+} while (!(__UART(LSR) & UART_LSR_##STATE))
+
+#define FLOWCTL_QUERY(LINE)     ({ __UART(MSR) & UART_MSR_##LINE; })
+#define FLOWCTL_CLEAR(LINE)     do { __UART(MCR) &= ~UART_MCR_##LINE; mb(); } while (0)
+#define FLOWCTL_SET(LINE)       do { __UART(MCR) |= UART_MCR_##LINE;  mb(); } while (0)
+
+#define FLOWCTL_WAIT_FOR(LINE)                  \
+do {                                            \
+        gdbstub_do_rx();                        \
+} while(!FLOWCTL_QUERY(LINE))
+
+/*****************************************************************************/
+/*
+ * initialise the GDB stub
+ * - called with PSR.ET==0, so can't incur external interrupts
+ */
+void gdbstub_io_init(void)
+{
+        /* set up the serial port */
+        __UART(LCR) = UART_LCR_WLEN8; /* 1N8 */
+        __UART(FCR) =
+                UART_FCR_ENABLE_FIFO |
+                UART_FCR_CLEAR_RCVR |
+                UART_FCR_CLEAR_XMIT |
+                UART_FCR_TRIGGER_1;
+
+        FLOWCTL_CLEAR(DTR);
+        FLOWCTL_SET(RTS);
+
+//      gdbstub_set_baud(115200);
+
+        /* we want to get serial receive interrupts */
+        __UART(IER) = UART_IER_RDI | UART_IER_RLSI;
+        mb();
+
+        __set_IRR(6, __UART_IRR_NMI);   /* map ERRs and UARTx to NMI */
+
+} /* end gdbstub_io_init() */
+
+/*****************************************************************************/
+/*
+ * set up the GDB stub serial port baud rate timers
+ */
+void gdbstub_set_baud(unsigned baud)
+{
+        unsigned value, high, low;
+        u8 lcr;
+
+        /* work out the divisor to give us the nearest higher baud rate */
+        value = __serial_clock_speed_HZ / 16 / baud;
+
+        /* determine the baud rate range */
+        high = __serial_clock_speed_HZ / 16 / value;
+        low = __serial_clock_speed_HZ / 16 / (value + 1);
+
+        /* pick the nearest bound */
+        if (low + (high - low) / 2 > baud)
+                value++;
+
+        lcr = __UART(LCR);
+        __UART(LCR) |= UART_LCR_DLAB;
+        mb();
+        __UART(DLL) = value & 0xff;
+        __UART(DLM) = (value >> 8) & 0xff;
+        mb();
+        __UART(LCR) = lcr;
+        mb();
+
+} /* end gdbstub_set_baud() */
+
+/*****************************************************************************/
+/*
+ * receive characters into the receive FIFO
+ */
+void gdbstub_do_rx(void)
+{
+        unsigned ix, nix;
+
+        ix = gdbstub_rx_inp;
+
+        while (__UART(LSR) & UART_LSR_DR) {
+                nix = (ix + 2) & 0xfff;
+                if (nix == gdbstub_rx_outp)
+                        break;
+
+                gdbstub_rx_buffer[ix++] = __UART(LSR);
+                gdbstub_rx_buffer[ix++] = __UART(RX);
+                ix = nix;
+        }
+
+        gdbstub_rx_inp = ix;
+
+        __clr_RC(15);
+        __clr_IRL();
+
+} /* end gdbstub_do_rx() */
+
+/*****************************************************************************/
+/*
+ * wait for a character to come from the debugger
+ */
+int gdbstub_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:
+        gdbstub_do_rx();
+
+        /* pull chars out of the buffer */
+        ix = gdbstub_rx_outp;
+        if (ix == gdbstub_rx_inp) {
+                if (nonblock)
+                        return -EAGAIN;
+                //watchdog_alert_counter = 0;
+                goto try_again;
+        }
+
+        st = gdbstub_rx_buffer[ix++];
+        ch = 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;
+        }
+
+} /* end gdbstub_rx_char() */
+
+/*****************************************************************************/
+/*
+ * send a character to the debugger
+ */
+void gdbstub_tx_char(unsigned char ch)
+{
+        FLOWCTL_SET(DTR);
+        LSR_WAIT_FOR(THRE);
+//      FLOWCTL_WAIT_FOR(CTS);
+
+        if (ch == 0x0a) {
+                __UART(TX) = 0x0d;
+                mb();
+                LSR_WAIT_FOR(THRE);
+//              FLOWCTL_WAIT_FOR(CTS);
+        }
+        __UART(TX) = ch;
+        mb();
+
+        FLOWCTL_CLEAR(DTR);
+} /* end gdbstub_tx_char() */
+
+/*****************************************************************************/
+/*
+ * send a character to the debugger
+ */
+void gdbstub_tx_flush(void)
+{
+        LSR_WAIT_FOR(TEMT);
+        LSR_WAIT_FOR(THRE);
+        FLOWCTL_CLEAR(DTR);
+} /* end gdbstub_tx_flush() */