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/* Copyright (c) 2009, 2010, 2011, 2012 ARM Ltd. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. The name of the company may not be used to endorse or promote
products derived from this software without specific prior written
permission.
THIS SOFTWARE IS PROVIDED BY ARM LTD ``AS IS'' AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL ARM LTD BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
#include "newlib.h"
#include "svc.h"
/* ANSI concatenation macros. */
#define CONCAT(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b
#ifdef __USER_LABEL_PREFIX__
#define FUNCTION( name ) CONCAT (__USER_LABEL_PREFIX__, name)
#else
#error __USER_LABEL_PREFIX is not defined
#endif
#ifdef HAVE_INITFINI_ARRAY
#define _init __libc_init_array
#define _fini __libc_fini_array
#endif
/* In ELF64, the large addressing model is used and R_AARCH64_ABS64
reloc is generated to relocate a 64-bit address. Since 64-bit
relocation is not available in ELF32, in order to have
a single code path for both ELF64 and ELF32 classes, we synthesize
a 64-bit relocation by using R_AARCH64_P32_ABS32 on one of the two
.word directives, depending on the endianness. */
.macro GEN_DWORD name
#if defined(__ILP32__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
.word \name
.word 0
#elif defined(__ILP32__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
.word 0
.word \name
#else
.dword \name
#endif
.endm
/* Help tackle the pointer size difference between ELF64 and ELF32. */
#ifdef __ILP32__
#define PTR_REG(n) w##n
#define PTR_SIZE 4
#define PTR_LOG_SIZE 2
#else
#define PTR_REG(n) x##n
#define PTR_SIZE 8
#define PTR_LOG_SIZE 3
#endif
.text
.macro FUNC_START name
.global \name
\name:
.endm
.align 2
FUNC_START _mainCRTStartup
FUNC_START _start
/* Start by setting up a stack */
/* Issue Angel SVC to read memory info.
ptr to ptr to 4 words to receive data. */
adr x1, .LC0
mov w0, #AngelSVC_Reason_HeapInfo
AngelSVCAsm AngelSVC
/* Initialise the stack pointer */
/* We currently choose to use the heap_limit field rather than
stack_base because the AEM validation model
returns sane values in the heap fields, but 0 in the stack
fields. Note on the VE AEM model it is necessary to pass
command line options to the AEM in order to define the values
exposed here in the HeapInfo Angel call. */
ldr x0, .LC0 /* point at returned values */
ldr x1, [x0, #8] /* get heap_limit */
#ifdef __ILP32__
/* Sanity check on the heap base. */
ldr x0, [x0] /* get heap_base */
tst x0, #0xffffffff00000000
beq 1f
/* Exit with 1 if the heap base is not within the 32-bit address
space. */
mov x0, ADP_Stopped_ApplicationExit & 0xff
movk x0, ADP_Stopped_ApplicationExit >> 16, lsl #16
adrp x1, HeapBase /* Reuse to construct the parameter block. */
add x1, x1, #:lo12:HeapBase
str x0, [x1]
mov x0, 1
str x0, [x1, #8]
mov w0, #AngelSVC_Reason_ReportException
AngelSVCAsm AngelSVC
1:
/* For the sake of safety, set the stack base to the top end of
the 32-bit address space if the returned value from the
Angel API call is larger than or equal to 4 GiB. */
tst x1, #0xffffffff00000000
csinv w1, w1, wzr, eq
#endif
/* Ensure quad-word stack alignment. */
and x0, x1, #~15
mov sp, x0
/* Setup an initial dummy frame with saved fp=0 and saved lr=0 */
mov x29, 0
stp x29, x29, [sp, #-16]!
mov x29, sp
/* Initialize exception vector table, flatmap, etc. */
bl FUNCTION (_cpu_init_hook)
/* Zero the memory in the .bss section. */
ldr x0, .LC1 /* First arg: start of memory block */
mov w1, #0 /* Second arg: fill value */
ldr x2, .LC2
sub x2, x2, x0 /* Third arg: length of block */
bl FUNCTION (memset)
#ifdef ARM_RDI_MONITOR
/* Need to set up standard file handles */
bl FUNCTION (initialise_monitor_handles)
#endif
/* .init and .fini sections are used to create constructors
and destructors. Here we call the _init function and arrange
for _fini to be called at program exit. */
ldr x0, .Lfini
bl FUNCTION (atexit)
bl FUNCTION (_init)
#ifdef ARM_RDI_MONITOR
/* Fetch and parse the command line. */
ldr x1, .Lcmdline /* Command line descriptor. */
mov w0, #AngelSVC_Reason_GetCmdLine
AngelSVCAsm AngelSVC
ldr x8, .Lcmdline
ldr x8, [x8]
mov x0, #0 /* argc */
mov x1, sp /* argv */
ldr x2, .Lenvp /* envp */
/* Put NULL at end of argv array. */
str PTR_REG (0), [x1, #-PTR_SIZE]!
/* Skip leading blanks. */
.Lnext: ldrb w3, [x8], #1
cbz w3, .Lendstr
cmp w3, #' '
b.eq .Lnext
mov w4, #' ' /* Terminator is space. */
/* See whether we are scanning a quoted string by checking for
opening quote (" or '). */
subs w9, w3, #'\"'
sub x8, x8, #1 /* Backup if no match. */
ccmp w9, #('\'' - '\"'), 0x4 /* FLG_Z */, ne
csel w4, w3, w4, eq /* Terminator = quote if match. */
cinc x8, x8, eq
/* Push arg pointer to argv, and bump argc. */
str PTR_REG (8), [x1, #-PTR_SIZE]!
add x0, x0, #1
/* Find end of arg string. */
1: ldrb w3, [x8], #1
cbz w3, .Lendstr
cmp w4, w3 /* Reached terminator? */
b.ne 1b
/* Terminate the arg string with NUL char. */
mov w4, #0
strb w4, [x8, #-1]
b .Lnext
/* Reverse argv array. */
.Lendstr:
add x3, x1, #0 /* sp = &argv[0] */
add x4, x1, w0, uxtw #PTR_LOG_SIZE /* ep = &argv[argc] */
cmp x4, x3
b.lo 2f
1: ldr PTR_REG (5), [x4, #-PTR_SIZE] /* PTR_REG (5) = ep[-1] */
ldr PTR_REG (6), [x3] /* PTR_REG (6) = *sp */
str PTR_REG (6), [x4, #-PTR_SIZE]! /* *--ep = PTR_REG (6) */
str PTR_REG (5), [x3], #PTR_SIZE /* *sp++ = PTR_REG (5) */
cmp x4, x3
b.hi 1b
2:
/* Move sp to the 16B boundary below argv. */
and x4, x1, ~15
mov sp, x4
#else
mov x0, #0 /* argc = 0 */
mov x1, #0 /* argv = NULL */
#endif
bl FUNCTION (main)
b FUNCTION (exit) /* Cannot return. */
/* Function initializing exception vector table, flatmap, etc.
Declared as weak symbol so that user can override this definition
by linking in their own version of the function. */
.weak FUNCTION (_cpu_init_hook)
FUNCTION (_cpu_init_hook):
ret
.align 3
.LC0:
GEN_DWORD HeapBase
.LC1:
GEN_DWORD __bss_start__
.LC2:
GEN_DWORD __bss_end__
.Lfini:
GEN_DWORD FUNCTION(_fini)
.Lenvp:
GEN_DWORD env
.Lcmdline:
GEN_DWORD AngelSVCArgs
/* Workspace for Angel calls. */
.data
.align 3
/* Data returned by monitor SVC. */
#if defined(__ILP32__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
.set __stack_base__, StackBase + 4
#else
.set __stack_base__, StackBase
#endif
.global __stack_base__
HeapBase: .dword 0
HeapLimit: .dword 0
StackBase: .dword 0
StackLimit: .dword 0
env: .dword 0 /* Dummy environment array */
CommandLine: .space 256,0 /* Maximum length of 255 chars handled. */
AngelSVCArgs:
GEN_DWORD CommandLine
.dword 255
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