semihosting: support fileio operation 66/3566/6
authorSteven Stallion <stallion@squareup.com>
Fri, 22 Jul 2016 20:43:11 +0000 (15:43 -0500)
committerPaul Fertser <fercerpav@gmail.com>
Thu, 8 Dec 2016 12:32:58 +0000 (12:32 +0000)
This patch adds support for bridging semihosting to GDB's File-I/O
remote protocol extension. For the most part operations match up 1:1,
however some require a working area to complete successfully, namely
operations that devolve to read, stat, and gettimeofday.

A new command was added to enable support for fileio named `arm
semihosting_fileio`, which ensures that the default behavior remains
intact for those that prefer it.

Finally, redundant logging was removed from the target_arch_state
function; this permits ARM targets to quiesce log output when polling
for a fileio reply. This prevents filling the logs with halt/resume
messages when using semihosting fileio.

Change-Id: Ifbb864fc2373336a501cc0332675b887b552e1ee
Signed-off-by: Steven Stallion <stallion@squareup.com>
Reviewed-on: http://openocd.zylin.com/3566
Tested-by: jenkins
Reviewed-by: Steven Stallion <sstallion@gmail.com>
Reviewed-by: Paul Fertser <fercerpav@gmail.com>
12 files changed:
doc/openocd.texi
src/target/arm.h
src/target/arm7tdmi.c
src/target/arm9tdmi.c
src/target/arm_semihosting.c
src/target/arm_semihosting.h
src/target/armv4_5.c
src/target/armv7m.c
src/target/cortex_a.c
src/target/cortex_m.c
src/target/hla_target.c
src/target/target.c

index 372683a..1cca4ab 100644 (file)
@@ -7404,6 +7404,17 @@ requests by using a special SVC instruction that is trapped at the
 Supervisor Call vector by OpenOCD.
 @end deffn
 
+@deffn Command {arm semihosting_fileio} [@option{enable}|@option{disable}]
+@cindex ARM semihosting
+Display status of semihosting fileio, after optionally changing that
+status.
+
+Enabling this option forwards semihosting I/O to GDB process using the
+File-I/O remote protocol extension. This is especially useful for
+interacting with remote files or displaying console messages in the
+debugger.
+@end deffn
+
 @section ARMv4 and ARMv5 Architecture
 @cindex ARMv4
 @cindex ARMv5
index 28022e3..226dd65 100644 (file)
@@ -130,6 +130,18 @@ struct arm {
        /** Flag reporting whether semihosting is active. */
        bool is_semihosting;
 
+       /** Flag reporting whether semihosting fileio is active. */
+       bool is_semihosting_fileio;
+
+       /** Flag reporting whether semihosting fileio operation is active. */
+       bool semihosting_hit_fileio;
+
+       /** Current semihosting operation. */
+       int semihosting_op;
+
+       /** Current semihosting result. */
+       int semihosting_result;
+
        /** Value to be returned by semihosting SYS_ERRNO request. */
        int semihosting_errno;
 
index 58ab027..9dcb302 100644 (file)
@@ -30,6 +30,7 @@
 #include "target_type.h"
 #include "register.h"
 #include "arm_opcodes.h"
+#include "arm_semihosting.h"
 
 /*
  * For information about ARM7TDMI, see ARM DDI 0210C (r4p1)
@@ -615,7 +616,7 @@ static void arm7tdmi_build_reg_cache(struct target *target)
 int arm7tdmi_init_target(struct command_context *cmd_ctx, struct target *target)
 {
        arm7tdmi_build_reg_cache(target);
-
+       arm_semihosting_init(target);
        return ERROR_OK;
 }
 
index eed965a..82b430f 100644 (file)
@@ -30,6 +30,7 @@
 #include "target_type.h"
 #include "register.h"
 #include "arm_opcodes.h"
+#include "arm_semihosting.h"
 
 /*
  * NOTE:  this holds code that's used with multiple ARM9 processors:
@@ -714,6 +715,7 @@ int arm9tdmi_init_target(struct command_context *cmd_ctx,
                struct target *target)
 {
        arm9tdmi_build_reg_cache(target);
+       arm_semihosting_init(target);
        return ERROR_OK;
 }
 
index 63335ff..2525119 100644 (file)
@@ -5,6 +5,9 @@
  *   Copyright (C) 2010 by Spencer Oliver                                  *
  *   spen@spen-soft.co.uk                                                  *
  *                                                                         *
+ *   Copyright (C) 2016 by Square, Inc.                                    *
+ *   Steven Stallion <stallion@squareup.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     *
@@ -43,6 +46,7 @@
 #include "cortex_m.h"
 #include "register.h"
 #include "arm_opcodes.h"
+#include "target_type.h"
 #include "arm_semihosting.h"
 #include <helper/binarybuffer.h>
 #include <helper/log.h>
@@ -63,13 +67,59 @@ static const int open_modeflags[12] = {
        O_RDWR | O_CREAT | O_APPEND | O_BINARY
 };
 
+static int post_result(struct target *target)
+{
+       struct arm *arm = target_to_arm(target);
+
+       /* REVISIT this looks wrong ... ARM11 and Cortex-A8
+        * should work this way at least sometimes.
+        */
+       if (is_arm7_9(target_to_arm7_9(target)) ||
+           is_armv7a(target_to_armv7a(target))) {
+               uint32_t spsr;
+
+               /* return value in R0 */
+               buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, arm->semihosting_result);
+               arm->core_cache->reg_list[0].dirty = 1;
+
+               /* LR --> PC */
+               buf_set_u32(arm->core_cache->reg_list[15].value, 0, 32,
+                       buf_get_u32(arm_reg_current(arm, 14)->value, 0, 32));
+               arm->core_cache->reg_list[15].dirty = 1;
+
+               /* saved PSR --> current PSR */
+               spsr = buf_get_u32(arm->spsr->value, 0, 32);
+
+               /* REVISIT should this be arm_set_cpsr(arm, spsr)
+                * instead of a partially unrolled version?
+                */
+
+               buf_set_u32(arm->cpsr->value, 0, 32, spsr);
+               arm->cpsr->dirty = 1;
+               arm->core_mode = spsr & 0x1f;
+               if (spsr & 0x20)
+                       arm->core_state = ARM_STATE_THUMB;
+
+       } else {
+               /* resume execution, this will be pc+2 to skip over the
+                * bkpt instruction */
+
+               /* return result in R0 */
+               buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, arm->semihosting_result);
+               arm->core_cache->reg_list[0].dirty = 1;
+       }
+
+       return ERROR_OK;
+}
+
 static int do_semihosting(struct target *target)
 {
        struct arm *arm = target_to_arm(target);
+       struct gdb_fileio_info *fileio_info = target->fileio_info;
        uint32_t r0 = buf_get_u32(arm->core_cache->reg_list[0].value, 0, 32);
        uint32_t r1 = buf_get_u32(arm->core_cache->reg_list[1].value, 0, 32);
        uint8_t params[16];
-       int retval, result;
+       int retval;
 
        /*
         * TODO: lots of security issues are not considered yet, such as:
@@ -77,10 +127,10 @@ static int do_semihosting(struct target *target)
         * - no safety checks on opened/deleted/renamed file paths
         * Beware the target app you use this support with.
         *
-        * TODO: explore mapping requests to GDB's "File-I/O Remote
-        * Protocol Extension" ... when GDB is active.
+        * TODO: unsupported semihosting fileio operations could be
+        * implemented if we had a small working area at our disposal.
         */
-       switch (r0) {
+       switch ((arm->semihosting_op = r0)) {
        case 0x01:      /* SYS_OPEN */
                retval = target_read_memory(target, r1, 4, 3, params);
                if (retval != ERROR_OK)
@@ -89,27 +139,40 @@ static int do_semihosting(struct target *target)
                        uint32_t a = target_buffer_get_u32(target, params+0);
                        uint32_t m = target_buffer_get_u32(target, params+4);
                        uint32_t l = target_buffer_get_u32(target, params+8);
-                       if (l <= 255 && m <= 11) {
-                               uint8_t fn[256];
-                               retval = target_read_memory(target, a, 1, l, fn);
-                               if (retval != ERROR_OK)
-                                       return retval;
-                               fn[l] = 0;
-                               if (strcmp((char *)fn, ":tt") == 0) {
-                                       if (m < 4)
-                                               result = dup(STDIN_FILENO);
-                                       else
-                                               result = dup(STDOUT_FILENO);
-                               } else {
-                                       /* cygwin requires the permission setting
-                                        * otherwise it will fail to reopen a previously
-                                        * written file */
-                                       result = open((char *)fn, open_modeflags[m], 0644);
+                       uint8_t fn[256];
+                       retval = target_read_memory(target, a, 1, l, fn);
+                       if (retval != ERROR_OK)
+                               return retval;
+                       fn[l] = 0;
+                       if (arm->is_semihosting_fileio) {
+                               if (strcmp((char *)fn, ":tt") == 0)
+                                       arm->semihosting_result = 0;
+                               else {
+                                       arm->semihosting_hit_fileio = true;
+                                       fileio_info->identifier = "open";
+                                       fileio_info->param_1 = a;
+                                       fileio_info->param_2 = l;
+                                       fileio_info->param_3 = open_modeflags[m];
+                                       fileio_info->param_4 = 0644;
                                }
-                               arm->semihosting_errno =  errno;
                        } else {
-                               result = -1;
-                               arm->semihosting_errno = EINVAL;
+                               if (l <= 255 && m <= 11) {
+                                       if (strcmp((char *)fn, ":tt") == 0) {
+                                               if (m < 4)
+                                                       arm->semihosting_result = dup(STDIN_FILENO);
+                                               else
+                                                       arm->semihosting_result = dup(STDOUT_FILENO);
+                                       } else {
+                                               /* cygwin requires the permission setting
+                                                * otherwise it will fail to reopen a previously
+                                                * written file */
+                                               arm->semihosting_result = open((char *)fn, open_modeflags[m], 0644);
+                                       }
+                                       arm->semihosting_errno =  errno;
+                               } else {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = EINVAL;
+                               }
                        }
                }
                break;
@@ -120,33 +183,63 @@ static int do_semihosting(struct target *target)
                        return retval;
                else {
                        int fd = target_buffer_get_u32(target, params+0);
-                       result = close(fd);
-                       arm->semihosting_errno = errno;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "close";
+                               fileio_info->param_1 = fd;
+                       } else {
+                               arm->semihosting_result = close(fd);
+                               arm->semihosting_errno = errno;
+                       }
                }
                break;
 
        case 0x03:      /* SYS_WRITEC */
-               {
+               if (arm->is_semihosting_fileio) {
+                       arm->semihosting_hit_fileio = true;
+                       fileio_info->identifier = "write";
+                       fileio_info->param_1 = 1;
+                       fileio_info->param_2 = r1;
+                       fileio_info->param_3 = 1;
+               } else {
                        unsigned char c;
                        retval = target_read_memory(target, r1, 1, 1, &c);
                        if (retval != ERROR_OK)
                                return retval;
                        putchar(c);
-                       result = 0;
+                       arm->semihosting_result = 0;
                }
                break;
 
        case 0x04:      /* SYS_WRITE0 */
-               do {
-                       unsigned char c;
-                       retval = target_read_memory(target, r1++, 1, 1, &c);
-                       if (retval != ERROR_OK)
-                               return retval;
-                       if (!c)
-                               break;
-                       putchar(c);
-               } while (1);
-               result = 0;
+               if (arm->is_semihosting_fileio) {
+                       size_t count = 0;
+                       for (uint32_t a = r1;; a++) {
+                               unsigned char c;
+                               retval = target_read_memory(target, a, 1, 1, &c);
+                               if (retval != ERROR_OK)
+                                       return retval;
+                               if (c == '\0')
+                                       break;
+                               count++;
+                       }
+                       arm->semihosting_hit_fileio = true;
+                       fileio_info->identifier = "write";
+                       fileio_info->param_1 = 1;
+                       fileio_info->param_2 = r1;
+                       fileio_info->param_3 = count;
+               } else {
+                       do {
+                               unsigned char c;
+                               retval = target_read_memory(target, r1++, 1, 1, &c);
+                               if (retval != ERROR_OK)
+                                       return retval;
+                               if (!c)
+                                       break;
+                               putchar(c);
+                       } while (1);
+                       arm->semihosting_result = 0;
+               }
                break;
 
        case 0x05:      /* SYS_WRITE */
@@ -157,21 +250,29 @@ static int do_semihosting(struct target *target)
                        int fd = target_buffer_get_u32(target, params+0);
                        uint32_t a = target_buffer_get_u32(target, params+4);
                        size_t l = target_buffer_get_u32(target, params+8);
-                       uint8_t *buf = malloc(l);
-                       if (!buf) {
-                               result = -1;
-                               arm->semihosting_errno = ENOMEM;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "write";
+                               fileio_info->param_1 = fd;
+                               fileio_info->param_2 = a;
+                               fileio_info->param_3 = l;
                        } else {
-                               retval = target_read_buffer(target, a, l, buf);
-                               if (retval != ERROR_OK) {
+                               uint8_t *buf = malloc(l);
+                               if (!buf) {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = ENOMEM;
+                               } else {
+                                       retval = target_read_buffer(target, a, l, buf);
+                                       if (retval != ERROR_OK) {
+                                               free(buf);
+                                               return retval;
+                                       }
+                                       arm->semihosting_result = write(fd, buf, l);
+                                       arm->semihosting_errno = errno;
+                                       if (arm->semihosting_result >= 0)
+                                               arm->semihosting_result = l - arm->semihosting_result;
                                        free(buf);
-                                       return retval;
                                }
-                               result = write(fd, buf, l);
-                               arm->semihosting_errno = errno;
-                               if (result >= 0)
-                                       result = l - result;
-                               free(buf);
                        }
                }
                break;
@@ -184,42 +285,60 @@ static int do_semihosting(struct target *target)
                        int fd = target_buffer_get_u32(target, params+0);
                        uint32_t a = target_buffer_get_u32(target, params+4);
                        ssize_t l = target_buffer_get_u32(target, params+8);
-                       uint8_t *buf = malloc(l);
-                       if (!buf) {
-                               result = -1;
-                               arm->semihosting_errno = ENOMEM;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "read";
+                               fileio_info->param_1 = fd;
+                               fileio_info->param_2 = a;
+                               fileio_info->param_3 = l;
                        } else {
-                               result = read(fd, buf, l);
-                               arm->semihosting_errno = errno;
-                               if (result >= 0) {
-                                       retval = target_write_buffer(target, a, result, buf);
-                                       if (retval != ERROR_OK) {
-                                               free(buf);
-                                               return retval;
+                               uint8_t *buf = malloc(l);
+                               if (!buf) {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = ENOMEM;
+                               } else {
+                                       arm->semihosting_result = read(fd, buf, l);
+                                       arm->semihosting_errno = errno;
+                                       if (arm->semihosting_result >= 0) {
+                                               retval = target_write_buffer(target, a, arm->semihosting_result, buf);
+                                               if (retval != ERROR_OK) {
+                                                       free(buf);
+                                                       return retval;
+                                               }
+                                               arm->semihosting_result = l - arm->semihosting_result;
                                        }
-                                       result = l - result;
+                                       free(buf);
                                }
-                               free(buf);
                        }
                }
                break;
 
        case 0x07:      /* SYS_READC */
-               result = getchar();
+               if (arm->is_semihosting_fileio) {
+                       LOG_ERROR("SYS_READC not supported by semihosting fileio");
+                       return ERROR_FAIL;
+               }
+               arm->semihosting_result = getchar();
                break;
 
        case 0x08:      /* SYS_ISERROR */
                retval = target_read_memory(target, r1, 4, 1, params);
                if (retval != ERROR_OK)
                        return retval;
-               result = (target_buffer_get_u32(target, params+0) != 0);
+               arm->semihosting_result = (target_buffer_get_u32(target, params+0) != 0);
                break;
 
        case 0x09:      /* SYS_ISTTY */
-               retval = target_read_memory(target, r1, 4, 1, params);
-               if (retval != ERROR_OK)
-                       return retval;
-               result = isatty(target_buffer_get_u32(target, params+0));
+               if (arm->is_semihosting_fileio) {
+                       arm->semihosting_hit_fileio = true;
+                       fileio_info->identifier = "isatty";
+                       fileio_info->param_1 = r1;
+               } else {
+                       retval = target_read_memory(target, r1, 4, 1, params);
+                       if (retval != ERROR_OK)
+                               return retval;
+                       arm->semihosting_result = isatty(target_buffer_get_u32(target, params+0));
+               }
                break;
 
        case 0x0a:      /* SYS_SEEK */
@@ -229,27 +348,39 @@ static int do_semihosting(struct target *target)
                else {
                        int fd = target_buffer_get_u32(target, params+0);
                        off_t pos = target_buffer_get_u32(target, params+4);
-                       result = lseek(fd, pos, SEEK_SET);
-                       arm->semihosting_errno = errno;
-                       if (result == pos)
-                               result = 0;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "lseek";
+                               fileio_info->param_1 = fd;
+                               fileio_info->param_2 = pos;
+                               fileio_info->param_3 = SEEK_SET;
+                       } else {
+                               arm->semihosting_result = lseek(fd, pos, SEEK_SET);
+                               arm->semihosting_errno = errno;
+                               if (arm->semihosting_result == pos)
+                                       arm->semihosting_result = 0;
+                       }
                }
                break;
 
        case 0x0c:      /* SYS_FLEN */
+               if (arm->is_semihosting_fileio) {
+                       LOG_ERROR("SYS_FLEN not supported by semihosting fileio");
+                       return ERROR_FAIL;
+               }
                retval = target_read_memory(target, r1, 4, 1, params);
                if (retval != ERROR_OK)
                        return retval;
                else {
                        int fd = target_buffer_get_u32(target, params+0);
                        struct stat buf;
-                       result = fstat(fd, &buf);
-                       if (result == -1) {
+                       arm->semihosting_result = fstat(fd, &buf);
+                       if (arm->semihosting_result == -1) {
                                arm->semihosting_errno = errno;
-                               result = -1;
+                               arm->semihosting_result = -1;
                                break;
                        }
-                       result = buf.st_size;
+                       arm->semihosting_result = buf.st_size;
                }
                break;
 
@@ -260,17 +391,24 @@ static int do_semihosting(struct target *target)
                else {
                        uint32_t a = target_buffer_get_u32(target, params+0);
                        uint32_t l = target_buffer_get_u32(target, params+4);
-                       if (l <= 255) {
-                               uint8_t fn[256];
-                               retval = target_read_memory(target, a, 1, l, fn);
-                               if (retval != ERROR_OK)
-                                       return retval;
-                               fn[l] = 0;
-                               result = remove((char *)fn);
-                               arm->semihosting_errno =  errno;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "unlink";
+                               fileio_info->param_1 = a;
+                               fileio_info->param_2 = l;
                        } else {
-                               result = -1;
-                               arm->semihosting_errno = EINVAL;
+                               if (l <= 255) {
+                                       uint8_t fn[256];
+                                       retval = target_read_memory(target, a, 1, l, fn);
+                                       if (retval != ERROR_OK)
+                                               return retval;
+                                       fn[l] = 0;
+                                       arm->semihosting_result = remove((char *)fn);
+                                       arm->semihosting_errno =  errno;
+                               } else {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = EINVAL;
+                               }
                        }
                }
                break;
@@ -284,31 +422,40 @@ static int do_semihosting(struct target *target)
                        uint32_t l1 = target_buffer_get_u32(target, params+4);
                        uint32_t a2 = target_buffer_get_u32(target, params+8);
                        uint32_t l2 = target_buffer_get_u32(target, params+12);
-                       if (l1 <= 255 && l2 <= 255) {
-                               uint8_t fn1[256], fn2[256];
-                               retval = target_read_memory(target, a1, 1, l1, fn1);
-                               if (retval != ERROR_OK)
-                                       return retval;
-                               retval = target_read_memory(target, a2, 1, l2, fn2);
-                               if (retval != ERROR_OK)
-                                       return retval;
-                               fn1[l1] = 0;
-                               fn2[l2] = 0;
-                               result = rename((char *)fn1, (char *)fn2);
-                               arm->semihosting_errno =  errno;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "rename";
+                               fileio_info->param_1 = a1;
+                               fileio_info->param_2 = l1;
+                               fileio_info->param_3 = a2;
+                               fileio_info->param_4 = l2;
                        } else {
-                               result = -1;
-                               arm->semihosting_errno = EINVAL;
+                               if (l1 <= 255 && l2 <= 255) {
+                                       uint8_t fn1[256], fn2[256];
+                                       retval = target_read_memory(target, a1, 1, l1, fn1);
+                                       if (retval != ERROR_OK)
+                                               return retval;
+                                       retval = target_read_memory(target, a2, 1, l2, fn2);
+                                       if (retval != ERROR_OK)
+                                               return retval;
+                                       fn1[l1] = 0;
+                                       fn2[l2] = 0;
+                                       arm->semihosting_result = rename((char *)fn1, (char *)fn2);
+                                       arm->semihosting_errno =  errno;
+                               } else {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = EINVAL;
+                               }
                        }
                }
                break;
 
        case 0x11:      /* SYS_TIME */
-               result = time(NULL);
+               arm->semihosting_result = time(NULL);
                break;
 
        case 0x13:      /* SYS_ERRNO */
-               result = arm->semihosting_errno;
+               arm->semihosting_result = arm->semihosting_errno;
                break;
 
        case 0x15:      /* SYS_GET_CMDLINE */
@@ -321,12 +468,12 @@ static int do_semihosting(struct target *target)
                        char *arg = "foobar";
                        uint32_t s = strlen(arg) + 1;
                        if (l < s)
-                               result = -1;
+                               arm->semihosting_result = -1;
                        else {
                                retval = target_write_buffer(target, a, s, (uint8_t *)arg);
                                if (retval != ERROR_OK)
                                        return retval;
-                               result = 0;
+                               arm->semihosting_result = 0;
                        }
                }
                break;
@@ -342,7 +489,7 @@ static int do_semihosting(struct target *target)
                        retval = target_write_memory(target, a, 4, 4, params);
                        if (retval != ERROR_OK)
                                return retval;
-                       result = 0;
+                       arm->semihosting_result = 0;
                }
                break;
 
@@ -386,17 +533,24 @@ static int do_semihosting(struct target *target)
                else {
                        uint32_t len = target_buffer_get_u32(target, params+4);
                        uint32_t c_ptr = target_buffer_get_u32(target, params);
-                       uint8_t cmd[256];
-                       if (len > 255) {
-                               result = -1;
-                               arm->semihosting_errno = EINVAL;
+                       if (arm->is_semihosting_fileio) {
+                               arm->semihosting_hit_fileio = true;
+                               fileio_info->identifier = "system";
+                               fileio_info->param_1 = c_ptr;
+                               fileio_info->param_2 = len;
                        } else {
-                               memset(cmd, 0x0, 256);
-                               retval = target_read_memory(target, c_ptr, 1, len, cmd);
-                               if (retval != ERROR_OK)
-                                       return retval;
-                               else
-                                       result = system((const char *)cmd);
+                               uint8_t cmd[256];
+                               if (len > 255) {
+                                       arm->semihosting_result = -1;
+                                       arm->semihosting_errno = EINVAL;
+                               } else {
+                                       memset(cmd, 0x0, 256);
+                                       retval = target_read_memory(target, c_ptr, 1, len, cmd);
+                                       if (retval != ERROR_OK)
+                                               return retval;
+                                       else
+                                               arm->semihosting_result = system((const char *)cmd);
+                               }
                        }
                }
                break;
@@ -408,51 +562,84 @@ static int do_semihosting(struct target *target)
        default:
                fprintf(stderr, "semihosting: unsupported call %#x\n",
                                (unsigned) r0);
-               result = -1;
+               arm->semihosting_result = -1;
                arm->semihosting_errno = ENOTSUP;
        }
 
-       /* resume execution to the original mode */
+       return ERROR_OK;
+}
 
-       /* REVISIT this looks wrong ... ARM11 and Cortex-A8
-        * should work this way at least sometimes.
+static int get_gdb_fileio_info(struct target *target, struct gdb_fileio_info *fileio_info)
+{
+       struct arm *arm = target_to_arm(target);
+
+       /* To avoid uneccessary duplication, semihosting prepares the
+        * fileio_info structure out-of-band when the target halts. See
+        * do_semihosting for more detail.
         */
-       if (is_arm7_9(target_to_arm7_9(target)) ||
-           is_armv7a(target_to_armv7a(target))) {
-               uint32_t spsr;
+       if (!arm->is_semihosting_fileio || !arm->semihosting_hit_fileio)
+               return ERROR_FAIL;
 
-               /* return value in R0 */
-               buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, result);
-               arm->core_cache->reg_list[0].dirty = 1;
+       return ERROR_OK;
+}
 
-               /* LR --> PC */
-               buf_set_u32(arm->core_cache->reg_list[15].value, 0, 32,
-                       buf_get_u32(arm_reg_current(arm, 14)->value, 0, 32));
-               arm->core_cache->reg_list[15].dirty = 1;
+static int gdb_fileio_end(struct target *target, int result, int fileio_errno, bool ctrl_c)
+{
+       struct arm *arm = target_to_arm(target);
+       struct gdb_fileio_info *fileio_info = target->fileio_info;
 
-               /* saved PSR --> current PSR */
-               spsr = buf_get_u32(arm->spsr->value, 0, 32);
+       /* clear pending status */
+       arm->semihosting_hit_fileio = false;
 
-               /* REVISIT should this be arm_set_cpsr(arm, spsr)
-                * instead of a partially unrolled version?
-                */
+       arm->semihosting_result = result;
+       arm->semihosting_errno = fileio_errno;
 
-               buf_set_u32(arm->cpsr->value, 0, 32, spsr);
-               arm->cpsr->dirty = 1;
-               arm->core_mode = spsr & 0x1f;
-               if (spsr & 0x20)
-                       arm->core_state = ARM_STATE_THUMB;
+       /* Some fileio results do not match up with what the semihosting
+        * operation expects; for these operations, we munge the results
+        * below:
+        */
+       switch (arm->semihosting_op) {
+       case 0x05:      /* SYS_WRITE */
+               if (result < 0)
+                       arm->semihosting_result = fileio_info->param_3;
+               else
+                       arm->semihosting_result = 0;
+               break;
 
-       } else {
-               /* resume execution, this will be pc+2 to skip over the
-                * bkpt instruction */
+       case 0x06:      /* SYS_READ */
+               if (result == (int)fileio_info->param_3)
+                       arm->semihosting_result = 0;
+               if (result <= 0)
+                       arm->semihosting_result = fileio_info->param_3;
+               break;
 
-               /* return result in R0 */
-               buf_set_u32(arm->core_cache->reg_list[0].value, 0, 32, result);
-               arm->core_cache->reg_list[0].dirty = 1;
+       case 0x0a:      /* SYS_SEEK */
+               if (result > 0)
+                       arm->semihosting_result = 0;
+               break;
        }
 
-       return target_resume(target, 1, 0, 0, 0);
+       return post_result(target);
+}
+
+/**
+ * Initialize ARM semihosting support.
+ *
+ * @param target Pointer to the ARM target to initialize.
+ * @return An error status if there is a problem during initialization.
+ */
+int arm_semihosting_init(struct target *target)
+{
+       target->fileio_info = malloc(sizeof(*target->fileio_info));
+       if (target->fileio_info == NULL) {
+               LOG_ERROR("out of memory");
+               return ERROR_FAIL;
+       }
+
+       target->type->get_gdb_fileio_info = get_gdb_fileio_info;
+       target->type->gdb_fileio_end = gdb_fileio_end;
+
+       return ERROR_OK;
 }
 
 /**
@@ -576,6 +763,35 @@ int arm_semihosting(struct target *target, int *retval)
                return 0;
        }
 
-       *retval = do_semihosting(target);
-       return 1;
+       /* Perform semihosting if we are not waiting on a fileio
+        * operation to complete.
+        */
+       if (!arm->semihosting_hit_fileio) {
+               *retval = do_semihosting(target);
+               if (*retval != ERROR_OK) {
+                       LOG_ERROR("Failed semihosting operation");
+                       return 0;
+               }
+       }
+
+       /* Post result to target if we are not waiting on a fileio
+        * operation to complete:
+        */
+       if (!arm->semihosting_hit_fileio) {
+               *retval = post_result(target);
+               if (*retval != ERROR_OK) {
+                       LOG_ERROR("Failed to post semihosting result");
+                       return 0;
+               }
+
+               *retval = target_resume(target, 1, 0, 0, 0);
+               if (*retval != ERROR_OK) {
+                       LOG_ERROR("Failed to resume target");
+                       return 0;
+               }
+
+               return 1;
+       }
+
+       return 0;
 }
index 7b5c0b2..011f19f 100644 (file)
@@ -19,6 +19,7 @@
 #ifndef OPENOCD_TARGET_ARM_SEMIHOSTING_H
 #define OPENOCD_TARGET_ARM_SEMIHOSTING_H
 
+int arm_semihosting_init(struct target *target);
 int arm_semihosting(struct target *target, int *retval);
 
 #endif /* OPENOCD_TARGET_ARM_SEMIHOSTING_H */
index 1a31d40..624a254 100644 (file)
@@ -666,14 +666,19 @@ int arm_arch_state(struct target *target)
                return ERROR_FAIL;
        }
 
+       /* avoid filling log waiting for fileio reply */
+       if (arm->semihosting_hit_fileio)
+               return ERROR_OK;
+
        LOG_USER("target halted in %s state due to %s, current mode: %s\n"
-               "cpsr: 0x%8.8" PRIx32 " pc: 0x%8.8" PRIx32 "%s",
+               "cpsr: 0x%8.8" PRIx32 " pc: 0x%8.8" PRIx32 "%s%s",
                arm_state_strings[arm->core_state],
                debug_reason_name(target),
                arm_mode_name(arm->core_mode),
                buf_get_u32(arm->cpsr->value, 0, 32),
                buf_get_u32(arm->pc->value, 0, 32),
-               arm->is_semihosting ? ", semihosting" : "");
+               arm->is_semihosting ? ", semihosting" : "",
+               arm->is_semihosting_fileio ? " fileio" : "");
 
        return ERROR_OK;
 }
@@ -1055,6 +1060,37 @@ COMMAND_HANDLER(handle_arm_semihosting_command)
        return ERROR_OK;
 }
 
+COMMAND_HANDLER(handle_arm_semihosting_fileio_command)
+{
+       struct target *target = get_current_target(CMD_CTX);
+
+       if (target == NULL) {
+               LOG_ERROR("No target selected");
+               return ERROR_FAIL;
+       }
+
+       struct arm *arm = target_to_arm(target);
+
+       if (!is_arm(arm)) {
+               command_print(CMD_CTX, "current target isn't an ARM");
+               return ERROR_FAIL;
+       }
+
+       if (!arm->is_semihosting) {
+               command_print(CMD_CTX, "semihosting is not enabled");
+               return ERROR_FAIL;
+       }
+
+       if (CMD_ARGC > 0)
+               COMMAND_PARSE_ENABLE(CMD_ARGV[0], arm->is_semihosting_fileio);
+
+       command_print(CMD_CTX, "semihosting fileio is %s",
+               arm->is_semihosting_fileio
+               ? "enabled" : "disabled");
+
+       return ERROR_OK;
+}
+
 static const struct command_registration arm_exec_command_handlers[] = {
        {
                .name = "reg",
@@ -1097,6 +1133,13 @@ static const struct command_registration arm_exec_command_handlers[] = {
                .usage = "['enable'|'disable']",
                .help = "activate support for semihosting operations",
        },
+       {
+               "semihosting_fileio",
+               .handler = handle_arm_semihosting_fileio_command,
+               .mode = COMMAND_EXEC,
+               .usage = "['enable'|'disable']",
+               .help = "activate support for semihosting fileio operations",
+       },
 
        COMMAND_REGISTRATION_DONE
 };
index 60b244a..64d18d7 100644 (file)
@@ -536,11 +536,15 @@ int armv7m_arch_state(struct target *target)
        struct arm *arm = &armv7m->arm;
        uint32_t ctrl, sp;
 
+       /* avoid filling log waiting for fileio reply */
+       if (arm->semihosting_hit_fileio)
+               return ERROR_OK;
+
        ctrl = buf_get_u32(arm->core_cache->reg_list[ARMV7M_CONTROL].value, 0, 32);
        sp = buf_get_u32(arm->core_cache->reg_list[ARMV7M_R13].value, 0, 32);
 
        LOG_USER("target halted due to %s, current mode: %s %s\n"
-               "xPSR: %#8.8" PRIx32 " pc: %#8.8" PRIx32 " %csp: %#8.8" PRIx32 "%s",
+               "xPSR: %#8.8" PRIx32 " pc: %#8.8" PRIx32 " %csp: %#8.8" PRIx32 "%s%s",
                debug_reason_name(target),
                arm_mode_name(arm->core_mode),
                armv7m_exception_string(armv7m->exception_number),
@@ -548,7 +552,8 @@ int armv7m_arch_state(struct target *target)
                buf_get_u32(arm->pc->value, 0, 32),
                (ctrl & 0x02) ? 'p' : 'm',
                sp,
-               arm->is_semihosting ? ", semihosting" : "");
+               arm->is_semihosting ? ", semihosting" : "",
+               arm->is_semihosting_fileio ? " fileio" : "");
 
        return ERROR_OK;
 }
index 91fa48e..ed2f613 100644 (file)
@@ -3103,6 +3103,7 @@ static int cortex_a_init_target(struct command_context *cmd_ctx,
        struct target *target)
 {
        /* examine_first() does a bunch of this */
+       arm_semihosting_init(target);
        return ERROR_OK;
 }
 
index 4270f8f..f674cc5 100644 (file)
@@ -1696,6 +1696,7 @@ static int cortex_m_init_target(struct command_context *cmd_ctx,
        struct target *target)
 {
        armv7m_build_reg_cache(target);
+       arm_semihosting_init(target);
        return ERROR_OK;
 }
 
index e02abc4..feeb11f 100644 (file)
@@ -341,7 +341,7 @@ static int adapter_init_target(struct command_context *cmd_ctx,
        LOG_DEBUG("%s", __func__);
 
        armv7m_build_reg_cache(target);
-
+       arm_semihosting_init(target);
        return ERROR_OK;
 }
 
index 26bae4b..17902a5 100644 (file)
@@ -1944,13 +1944,10 @@ int target_arch_state(struct target *target)
 {
        int retval;
        if (target == NULL) {
-               LOG_USER("No target has been configured");
+               LOG_WARNING("No target has been configured");
                return ERROR_OK;
        }
 
-       LOG_USER("%s: target state: %s", target_name(target),
-                target_state_name(target));
-
        if (target->state != TARGET_HALTED)
                return ERROR_OK;