src/arch/mips/process.cc

   1 /*
   2  * Copyright (c) 2004-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Gabe Black
  29  *          Ali Saidi
  30  *          Korey Sewell
  31  */
  32
  33 #include "arch/mips/isa_traits.hh"
  34 #include "arch/mips/process.hh"
  35
  36 #include "base/loader/object_file.hh"
  37 #include "base/misc.hh"
  38 #include "cpu/thread_context.hh"
  39
  40 #include "mem/page_table.hh"
  41
  42 #include "sim/process.hh"
  43 #include "sim/process_impl.hh"
  44 #include "sim/system.hh"
  45
  46 using namespace std;
  47 using namespace MipsISA;
  48
  49 MipsLiveProcess::MipsLiveProcess(LiveProcessParams * params,
  50         ObjectFile *objFile)
  51     : LiveProcess(params, objFile)
  52 {
  53     // Set up stack. On MIPS, stack starts at the top of kuseg
  54     // user address space. MIPS stack grows down from here
  55     stack_base = 0x7FFFFFFF;
  56
  57     // Set pointer for next thread stack.  Reserve 8M for main stack.
  58     next_thread_stack_base = stack_base - (8 * 1024 * 1024);
  59
  60     // Set up break point (Top of Heap)
  61     brk_point = objFile->dataBase() + objFile->dataSize() + objFile->bssSize();
  62     brk_point = roundUp(brk_point, VMPageSize);
  63
  64     // Set up region for mmaps. For now, start at bottom of kuseg space.
  65     mmap_start = mmap_end = 0x10000;
  66 }
  67
  68 void
  69 MipsLiveProcess::startup()
  70 {
  71     Process::startup();
  72
  73     argsInit(MachineBytes, VMPageSize);
  74 }
  75
  76 void
  77 MipsLiveProcess::argsInit(int intSize, int pageSize)
  78 {
  79     // load object file into target memory
  80     objFile->loadSections(initVirtMem);
  81
  82     // Calculate how much space we need for arg & env arrays.
  83     int argv_array_size = intSize * (argv.size() + 1);
  84     int envp_array_size = intSize * (envp.size() + 1);
  85     int arg_data_size = 0;
  86     for (vector<string>::size_type i = 0; i < argv.size(); ++i) {
  87         arg_data_size += argv[i].size() + 1;
  88     }
  89     int env_data_size = 0;
  90     for (vector<string>::size_type i = 0; i < envp.size(); ++i) {
  91         env_data_size += envp[i].size() + 1;
  92     }
  93
  94     int space_needed =
  95          argv_array_size + envp_array_size + arg_data_size + env_data_size;
  96     if (space_needed < 32*1024)
  97         space_needed = 32*1024;
  98
  99     // set bottom of stack
 100     stack_min = stack_base - space_needed;
 101     // align it
 102     stack_min = roundDown(stack_min, pageSize);
 103     stack_size = stack_base - stack_min;
 104     // map memory
 105     pTable->allocate(stack_min, roundUp(stack_size, pageSize));
 106
 107     // map out initial stack contents
 108     // ========
 109     // NOTE: Using uint32_t hardcodes MIPS32 and not MIPS64
 110     // even if MIPS64 was intended. This is because the
 111     // copyStringArray function templates on the parameters.
 112     // Elegant way to check intSize and vary between 32/64?
 113     // ========
 114     uint32_t argv_array_base = stack_min + intSize; // room for argc
 115     uint32_t envp_array_base = argv_array_base + argv_array_size;
 116     uint32_t arg_data_base = envp_array_base + envp_array_size;
 117     uint32_t env_data_base = arg_data_base + arg_data_size;
 118
 119     // write contents to stack
 120     uint32_t argc = argv.size();
 121
 122     if (intSize == 8)
 123         argc = htog((uint64_t)argc);
 124     else if (intSize == 4)
 125         argc = htog((uint32_t)argc);
 126     else
 127         panic("Unknown int size");
 128
 129
 130     initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize);
 131
 132     copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
 133
 134     copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
 135
 136     ThreadContext *tc = system->getThreadContext(contextIds[0]);
 137
 138     setSyscallArg(tc, 0, argc);
 139     setSyscallArg(tc, 1, argv_array_base);
 140     tc->setIntReg(StackPointerReg, stack_min);
 141
 142     Addr prog_entry = objFile->entryPoint();
 143     tc->setPC(prog_entry);
 144     tc->setNextPC(prog_entry + sizeof(MachInst));
 145     tc->setNextNPC(prog_entry + (2 * sizeof(MachInst)));
 146 }
 147
 148
 149 MipsISA::IntReg
 150 MipsLiveProcess::getSyscallArg(ThreadContext *tc, int &i)
 151 {
 152     assert(i < 6);
 153     return tc->readIntReg(FirstArgumentReg + i++);
 154 }
 155
 156 void
 157 MipsLiveProcess::setSyscallArg(ThreadContext *tc,
 158         int i, MipsISA::IntReg val)
 159 {
 160     assert(i < 6);
 161     tc->setIntReg(FirstArgumentReg + i, val);
 162 }
 163
 164 void
 165 MipsLiveProcess::setSyscallReturn(ThreadContext *tc,
 166         SyscallReturn return_value)
 167 {
 168     if (return_value.successful()) {
 169         // no error
 170         tc->setIntReg(SyscallSuccessReg, 0);
 171         tc->setIntReg(ReturnValueReg, return_value.value());
 172     } else {
 173         // got an error, return details
 174         tc->setIntReg(SyscallSuccessReg, (IntReg) -1);
 175         tc->setIntReg(ReturnValueReg, -return_value.value());
 176     }
 177 }