From: Gabe Black Date: Mon, 27 Jul 2009 07:52:31 +0000 (-0700) Subject: ARM: Set up the initial stack frame to match a recent Linux. X-Git-Tag: Calvin_Submission~194^2~24 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b8bf34be05648d73d1ff6cdb9b831145544a38df;p=gem5.git ARM: Set up the initial stack frame to match a recent Linux. --- diff --git a/src/arch/arm/process.cc b/src/arch/arm/process.cc index 365d5b22c..cd7cc9736 100644 --- a/src/arch/arm/process.cc +++ b/src/arch/arm/process.cc @@ -46,7 +46,7 @@ using namespace ArmISA; ArmLiveProcess::ArmLiveProcess(LiveProcessParams *params, ObjectFile *objFile) : LiveProcess(params, objFile) { - stack_base = 0xc0000000L; + stack_base = 0xbf000000L; // Set pointer for next thread stack. Reserve 8M for main stack. next_thread_stack_base = stack_base - (8 * 1024 * 1024); @@ -88,73 +88,239 @@ ArmLiveProcess::copyStringArray32(std::vector &strings, void ArmLiveProcess::argsInit(int intSize, int pageSize) { + typedef AuxVector auxv_t; + std::vector auxv; + + string filename; + if (argv.size() < 1) + filename = ""; + else + filename = argv[0]; + + //We want 16 byte alignment + uint64_t align = 16; + // Overloaded argsInit so that we can fine-tune for ARM architecture Process::startup(); // load object file into target memory objFile->loadSections(initVirtMem); - // Calculate how much space we need for arg & env arrays. - int argv_array_size = intSize * (argv.size() + 1); - int envp_array_size = intSize * (envp.size() + 1); - int arg_data_size = 0; - for (int i = 0; i < argv.size(); ++i) { - arg_data_size += argv[i].size() + 1; + enum ArmCpuFeature { + Arm_Swp = 1 << 0, + Arm_Half = 1 << 1, + Arm_Thumb = 1 << 2, + Arm_26Bit = 1 << 3, + Arm_FastMult = 1 << 4, + Arm_Fpa = 1 << 5, + Arm_Vfp = 1 << 6, + Arm_Edsp = 1 << 7, + Arm_Java = 1 << 8, + Arm_Iwmmxt = 1 << 9, + Arm_Crunch = 1 << 10 + }; + + //Setup the auxilliary vectors. These will already have endian conversion. + //Auxilliary vectors are loaded only for elf formatted executables. + ElfObject * elfObject = dynamic_cast(objFile); + if (elfObject) { + uint32_t features = + Arm_Swp | + Arm_Half | + Arm_Thumb | +// Arm_26Bit | + Arm_FastMult | +// Arm_Fpa | + Arm_Vfp | + Arm_Edsp | + Arm_Java | +// Arm_Iwmmxt | +// Arm_Crunch | + 0; + + //Bits which describe the system hardware capabilities + //XXX Figure out what these should be + auxv.push_back(auxv_t(M5_AT_HWCAP, features)); + //The system page size + auxv.push_back(auxv_t(M5_AT_PAGESZ, ArmISA::VMPageSize)); + //Frequency at which times() increments + auxv.push_back(auxv_t(M5_AT_CLKTCK, 0x64)); + // For statically linked executables, this is the virtual address of the + // program header tables if they appear in the executable image + auxv.push_back(auxv_t(M5_AT_PHDR, elfObject->programHeaderTable())); + // This is the size of a program header entry from the elf file. + auxv.push_back(auxv_t(M5_AT_PHENT, elfObject->programHeaderSize())); + // This is the number of program headers from the original elf file. + auxv.push_back(auxv_t(M5_AT_PHNUM, elfObject->programHeaderCount())); + //This is the address of the elf "interpreter", It should be set + //to 0 for regular executables. It should be something else + //(not sure what) for dynamic libraries. + auxv.push_back(auxv_t(M5_AT_BASE, 0)); + + //XXX Figure out what this should be. + auxv.push_back(auxv_t(M5_AT_FLAGS, 0)); + //The entry point to the program + auxv.push_back(auxv_t(M5_AT_ENTRY, objFile->entryPoint())); + //Different user and group IDs + auxv.push_back(auxv_t(M5_AT_UID, uid())); + auxv.push_back(auxv_t(M5_AT_EUID, euid())); + auxv.push_back(auxv_t(M5_AT_GID, gid())); + auxv.push_back(auxv_t(M5_AT_EGID, egid())); + //Whether to enable "secure mode" in the executable + auxv.push_back(auxv_t(M5_AT_SECURE, 0)); + //The filename of the program + auxv.push_back(auxv_t(M5_AT_EXECFN, 0)); + //The string "v51" with unknown meaning + auxv.push_back(auxv_t(M5_AT_PLATFORM, 0)); } + + //Figure out how big the initial stack nedes to be + + // A sentry NULL void pointer at the top of the stack. + int sentry_size = intSize; + + string platform = "v51"; + int platform_size = platform.size() + 1; + + // The aux vectors are put on the stack in two groups. The first group are + // the vectors that are generated as the elf is loaded. The second group + // are the ones that were computed ahead of time and include the platform + // string. + int aux_data_size = filename.size() + 1; + int env_data_size = 0; for (int i = 0; i < envp.size(); ++i) { env_data_size += envp[i].size() + 1; } + int arg_data_size = 0; + for (int i = 0; i < argv.size(); ++i) { + arg_data_size += argv[i].size() + 1; + } - int space_needed = - argv_array_size + envp_array_size + arg_data_size + env_data_size; - if (space_needed < 16*1024) - space_needed = 16*1024; + int info_block_size = + sentry_size + env_data_size + arg_data_size + + aux_data_size + platform_size; + + //Each auxilliary vector is two 4 byte words + int aux_array_size = intSize * 2 * (auxv.size() + 1); + + int envp_array_size = intSize * (envp.size() + 1); + int argv_array_size = intSize * (argv.size() + 1); + + int argc_size = intSize; + + //Figure out the size of the contents of the actual initial frame + int frame_size = + info_block_size + + aux_array_size + + envp_array_size + + argv_array_size + + argc_size; + + //There needs to be padding after the auxiliary vector data so that the + //very bottom of the stack is aligned properly. + int partial_size = frame_size; + int aligned_partial_size = roundUp(partial_size, align); + int aux_padding = aligned_partial_size - partial_size; + + int space_needed = frame_size + aux_padding; - // set bottom of stack stack_min = stack_base - space_needed; - // align it - stack_min = roundDown(stack_min, pageSize); + stack_min = roundDown(stack_min, align); stack_size = stack_base - stack_min; + // map memory - pTable->allocate(stack_min, roundUp(stack_size, pageSize)); + pTable->allocate(roundDown(stack_min, pageSize), + roundUp(stack_size, pageSize)); // map out initial stack contents - Addr argv_array_base = stack_min + intSize; // room for argc - Addr envp_array_base = argv_array_base + argv_array_size; - Addr arg_data_base = envp_array_base + envp_array_size; - Addr env_data_base = arg_data_base + arg_data_size; + uint32_t sentry_base = stack_base - sentry_size; + uint32_t aux_data_base = sentry_base - aux_data_size; + uint32_t env_data_base = aux_data_base - env_data_size; + uint32_t arg_data_base = env_data_base - arg_data_size; + uint32_t platform_base = arg_data_base - platform_size; + uint32_t auxv_array_base = platform_base - aux_array_size - aux_padding; + uint32_t envp_array_base = auxv_array_base - envp_array_size; + uint32_t argv_array_base = envp_array_base - argv_array_size; + uint32_t argc_base = argv_array_base - argc_size; + + DPRINTF(Stack, "The addresses of items on the initial stack:\n"); + DPRINTF(Stack, "0x%x - aux data\n", aux_data_base); + DPRINTF(Stack, "0x%x - env data\n", env_data_base); + DPRINTF(Stack, "0x%x - arg data\n", arg_data_base); + DPRINTF(Stack, "0x%x - platform base\n", platform_base); + DPRINTF(Stack, "0x%x - auxv array\n", auxv_array_base); + DPRINTF(Stack, "0x%x - envp array\n", envp_array_base); + DPRINTF(Stack, "0x%x - argv array\n", argv_array_base); + DPRINTF(Stack, "0x%x - argc \n", argc_base); + DPRINTF(Stack, "0x%x - stack min\n", stack_min); // write contents to stack - uint64_t argc = argv.size(); - if (intSize == 8) - argc = htog((uint64_t)argc); - else if (intSize == 4) - argc = htog((uint32_t)argc); - else - panic("Unknown int size"); - initVirtMem->writeBlob(stack_min, (uint8_t*)&argc, intSize); + // figure out argc + uint32_t argc = argv.size(); + uint32_t guestArgc = ArmISA::htog(argc); - copyStringArray32(argv, argv_array_base, arg_data_base, initVirtMem); - copyStringArray32(envp, envp_array_base, env_data_base, initVirtMem); + //Write out the sentry void * + uint32_t sentry_NULL = 0; + initVirtMem->writeBlob(sentry_base, + (uint8_t*)&sentry_NULL, sentry_size); - /* - //uint8_t insns[] = {0xe5, 0x9f, 0x00, 0x08, 0xe1, 0xa0, 0xf0, 0x0e}; - uint8_t insns[] = {0x08, 0x00, 0x9f, 0xe5, 0x0e, 0xf0, 0xa0, 0xe1}; + //Fix up the aux vectors which point to other data + for (int i = auxv.size() - 1; i >= 0; i--) { + if (auxv[i].a_type == M5_AT_PLATFORM) { + auxv[i].a_val = platform_base; + initVirtMem->writeString(platform_base, platform.c_str()); + } else if (auxv[i].a_type == M5_AT_EXECFN) { + auxv[i].a_val = aux_data_base; + initVirtMem->writeString(aux_data_base, filename.c_str()); + } + } - initVirtMem->writeBlob(0xffff0fe0, insns, 8); - */ + //Copy the aux stuff + for(int x = 0; x < auxv.size(); x++) + { + initVirtMem->writeBlob(auxv_array_base + x * 2 * intSize, + (uint8_t*)&(auxv[x].a_type), intSize); + initVirtMem->writeBlob(auxv_array_base + (x * 2 + 1) * intSize, + (uint8_t*)&(auxv[x].a_val), intSize); + } + //Write out the terminating zeroed auxilliary vector + const uint64_t zero = 0; + initVirtMem->writeBlob(auxv_array_base + 2 * intSize * auxv.size(), + (uint8_t*)&zero, 2 * intSize); - ThreadContext *tc = system->getThreadContext(contextIds[0]); + copyStringArray(envp, envp_array_base, env_data_base, initVirtMem); + copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem); + + initVirtMem->writeBlob(argc_base, (uint8_t*)&guestArgc, intSize); - tc->setIntReg(ArgumentReg1, argc); - tc->setIntReg(ArgumentReg2, argv_array_base); + ThreadContext *tc = system->getThreadContext(contextIds[0]); + //Set the stack pointer register tc->setIntReg(StackPointerReg, stack_min); + //A pointer to a function to run when the program exits. We'll set this + //to zero explicitly to make sure this isn't used. + tc->setIntReg(ArgumentReg0, 0); + //Set argument regs 1 and 2 to argv[0] and envp[0] respectively + if (argv.size() > 0) { + tc->setIntReg(ArgumentReg1, arg_data_base + arg_data_size - + argv[argv.size() - 1].size() - 1); + } else { + tc->setIntReg(ArgumentReg1, 0); + } + if (envp.size() > 0) { + tc->setIntReg(ArgumentReg2, env_data_base + env_data_size - + envp[envp.size() - 1].size() - 1); + } else { + tc->setIntReg(ArgumentReg2, 0); + } Addr prog_entry = objFile->entryPoint(); tc->setPC(prog_entry); tc->setNextPC(prog_entry + sizeof(MachInst)); + + //Align the "stack_min" to a page boundary. + stack_min = roundDown(stack_min, pageSize); } ArmISA::IntReg