Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* gdb-io.c: FR403 GDB stub I/O |
| 2 | * |
| 3 | * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. |
| 4 | * Written by David Howells (dhowells@redhat.com) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/string.h> |
| 13 | #include <linux/kernel.h> |
| 14 | #include <linux/signal.h> |
| 15 | #include <linux/sched.h> |
| 16 | #include <linux/mm.h> |
| 17 | #include <linux/console.h> |
| 18 | #include <linux/init.h> |
| 19 | #include <linux/serial_reg.h> |
| 20 | |
| 21 | #include <asm/pgtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #include <asm/irc-regs.h> |
| 23 | #include <asm/timer-regs.h> |
| 24 | #include <asm/gdb-stub.h> |
| 25 | #include "gdb-io.h" |
| 26 | |
| 27 | #ifdef CONFIG_GDBSTUB_UART0 |
| 28 | #define __UART(X) (*(volatile uint8_t *)(UART0_BASE + (UART_##X))) |
| 29 | #define __UART_IRR_NMI 0xff0f0000 |
| 30 | #else /* CONFIG_GDBSTUB_UART1 */ |
| 31 | #define __UART(X) (*(volatile uint8_t *)(UART1_BASE + (UART_##X))) |
| 32 | #define __UART_IRR_NMI 0xfff00000 |
| 33 | #endif |
| 34 | |
| 35 | #define LSR_WAIT_FOR(STATE) \ |
| 36 | do { \ |
| 37 | gdbstub_do_rx(); \ |
| 38 | } while (!(__UART(LSR) & UART_LSR_##STATE)) |
| 39 | |
| 40 | #define FLOWCTL_QUERY(LINE) ({ __UART(MSR) & UART_MSR_##LINE; }) |
| 41 | #define FLOWCTL_CLEAR(LINE) do { __UART(MCR) &= ~UART_MCR_##LINE; mb(); } while (0) |
| 42 | #define FLOWCTL_SET(LINE) do { __UART(MCR) |= UART_MCR_##LINE; mb(); } while (0) |
| 43 | |
| 44 | #define FLOWCTL_WAIT_FOR(LINE) \ |
| 45 | do { \ |
| 46 | gdbstub_do_rx(); \ |
| 47 | } while(!FLOWCTL_QUERY(LINE)) |
| 48 | |
| 49 | /*****************************************************************************/ |
| 50 | /* |
| 51 | * initialise the GDB stub |
| 52 | * - called with PSR.ET==0, so can't incur external interrupts |
| 53 | */ |
| 54 | void gdbstub_io_init(void) |
| 55 | { |
| 56 | /* set up the serial port */ |
| 57 | __UART(LCR) = UART_LCR_WLEN8; /* 1N8 */ |
| 58 | __UART(FCR) = |
| 59 | UART_FCR_ENABLE_FIFO | |
| 60 | UART_FCR_CLEAR_RCVR | |
| 61 | UART_FCR_CLEAR_XMIT | |
| 62 | UART_FCR_TRIGGER_1; |
| 63 | |
| 64 | FLOWCTL_CLEAR(DTR); |
| 65 | FLOWCTL_SET(RTS); |
| 66 | |
| 67 | // gdbstub_set_baud(115200); |
| 68 | |
| 69 | /* we want to get serial receive interrupts */ |
| 70 | __UART(IER) = UART_IER_RDI | UART_IER_RLSI; |
| 71 | mb(); |
| 72 | |
| 73 | __set_IRR(6, __UART_IRR_NMI); /* map ERRs and UARTx to NMI */ |
| 74 | |
| 75 | } /* end gdbstub_io_init() */ |
| 76 | |
| 77 | /*****************************************************************************/ |
| 78 | /* |
| 79 | * set up the GDB stub serial port baud rate timers |
| 80 | */ |
| 81 | void gdbstub_set_baud(unsigned baud) |
| 82 | { |
| 83 | unsigned value, high, low; |
| 84 | u8 lcr; |
| 85 | |
| 86 | /* work out the divisor to give us the nearest higher baud rate */ |
| 87 | value = __serial_clock_speed_HZ / 16 / baud; |
| 88 | |
| 89 | /* determine the baud rate range */ |
| 90 | high = __serial_clock_speed_HZ / 16 / value; |
| 91 | low = __serial_clock_speed_HZ / 16 / (value + 1); |
| 92 | |
| 93 | /* pick the nearest bound */ |
| 94 | if (low + (high - low) / 2 > baud) |
| 95 | value++; |
| 96 | |
| 97 | lcr = __UART(LCR); |
| 98 | __UART(LCR) |= UART_LCR_DLAB; |
| 99 | mb(); |
| 100 | __UART(DLL) = value & 0xff; |
| 101 | __UART(DLM) = (value >> 8) & 0xff; |
| 102 | mb(); |
| 103 | __UART(LCR) = lcr; |
| 104 | mb(); |
| 105 | |
| 106 | } /* end gdbstub_set_baud() */ |
| 107 | |
| 108 | /*****************************************************************************/ |
| 109 | /* |
| 110 | * receive characters into the receive FIFO |
| 111 | */ |
| 112 | void gdbstub_do_rx(void) |
| 113 | { |
| 114 | unsigned ix, nix; |
| 115 | |
| 116 | ix = gdbstub_rx_inp; |
| 117 | |
| 118 | while (__UART(LSR) & UART_LSR_DR) { |
| 119 | nix = (ix + 2) & 0xfff; |
| 120 | if (nix == gdbstub_rx_outp) |
| 121 | break; |
| 122 | |
| 123 | gdbstub_rx_buffer[ix++] = __UART(LSR); |
| 124 | gdbstub_rx_buffer[ix++] = __UART(RX); |
| 125 | ix = nix; |
| 126 | } |
| 127 | |
| 128 | gdbstub_rx_inp = ix; |
| 129 | |
| 130 | __clr_RC(15); |
| 131 | __clr_IRL(); |
| 132 | |
| 133 | } /* end gdbstub_do_rx() */ |
| 134 | |
| 135 | /*****************************************************************************/ |
| 136 | /* |
| 137 | * wait for a character to come from the debugger |
| 138 | */ |
| 139 | int gdbstub_rx_char(unsigned char *_ch, int nonblock) |
| 140 | { |
| 141 | unsigned ix; |
| 142 | u8 ch, st; |
| 143 | |
| 144 | *_ch = 0xff; |
| 145 | |
| 146 | if (gdbstub_rx_unget) { |
| 147 | *_ch = gdbstub_rx_unget; |
| 148 | gdbstub_rx_unget = 0; |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | try_again: |
| 153 | gdbstub_do_rx(); |
| 154 | |
| 155 | /* pull chars out of the buffer */ |
| 156 | ix = gdbstub_rx_outp; |
| 157 | if (ix == gdbstub_rx_inp) { |
| 158 | if (nonblock) |
| 159 | return -EAGAIN; |
| 160 | //watchdog_alert_counter = 0; |
| 161 | goto try_again; |
| 162 | } |
| 163 | |
| 164 | st = gdbstub_rx_buffer[ix++]; |
| 165 | ch = gdbstub_rx_buffer[ix++]; |
| 166 | gdbstub_rx_outp = ix & 0x00000fff; |
| 167 | |
| 168 | if (st & UART_LSR_BI) { |
| 169 | gdbstub_proto("### GDB Rx Break Detected ###\n"); |
| 170 | return -EINTR; |
| 171 | } |
| 172 | else if (st & (UART_LSR_FE|UART_LSR_OE|UART_LSR_PE)) { |
David Howells | 7ca8b9c | 2010-05-24 14:32:54 -0700 | [diff] [blame] | 173 | gdbstub_io("### GDB Rx Error (st=%02x) ###\n",st); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | return -EIO; |
| 175 | } |
| 176 | else { |
David Howells | 7ca8b9c | 2010-05-24 14:32:54 -0700 | [diff] [blame] | 177 | gdbstub_io("### GDB Rx %02x (st=%02x) ###\n",ch,st); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | *_ch = ch & 0x7f; |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | } /* end gdbstub_rx_char() */ |
| 183 | |
| 184 | /*****************************************************************************/ |
| 185 | /* |
| 186 | * send a character to the debugger |
| 187 | */ |
| 188 | void gdbstub_tx_char(unsigned char ch) |
| 189 | { |
| 190 | FLOWCTL_SET(DTR); |
| 191 | LSR_WAIT_FOR(THRE); |
| 192 | // FLOWCTL_WAIT_FOR(CTS); |
| 193 | |
| 194 | if (ch == 0x0a) { |
| 195 | __UART(TX) = 0x0d; |
| 196 | mb(); |
| 197 | LSR_WAIT_FOR(THRE); |
| 198 | // FLOWCTL_WAIT_FOR(CTS); |
| 199 | } |
| 200 | __UART(TX) = ch; |
| 201 | mb(); |
| 202 | |
| 203 | FLOWCTL_CLEAR(DTR); |
| 204 | } /* end gdbstub_tx_char() */ |
| 205 | |
| 206 | /*****************************************************************************/ |
| 207 | /* |
| 208 | * send a character to the debugger |
| 209 | */ |
| 210 | void gdbstub_tx_flush(void) |
| 211 | { |
| 212 | LSR_WAIT_FOR(TEMT); |
| 213 | LSR_WAIT_FOR(THRE); |
| 214 | FLOWCTL_CLEAR(DTR); |
| 215 | } /* end gdbstub_tx_flush() */ |