diff options
Diffstat (limited to 'libgloss/arm/crt0.S')
| -rw-r--r-- | libgloss/arm/crt0.S | 520 |
1 files changed, 0 insertions, 520 deletions
diff --git a/libgloss/arm/crt0.S b/libgloss/arm/crt0.S deleted file mode 100644 index cc1c37091..000000000 --- a/libgloss/arm/crt0.S +++ /dev/null @@ -1,520 +0,0 @@ -#include "newlib.h" -#include "arm.h" -#include "swi.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 - -#if defined(__ARM_EABI__) && defined(__thumb__) && !defined(__thumb2__) -/* For Thumb1 we need to force the architecture to be sure that we get the - correct attributes on the object file; otherwise the assembler will get - confused and mark the object as being v6T2. */ -#if defined(__ARM_ARCH_4T__) - .arch armv4t -#elif defined(__ARM_ARCH_5T__) || defined(__ARM_ARCH_5TE__) - /* Nothing in this object requires higher than v5. */ - .arch armv5t -#elif defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \ - || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \ - || defined(__ARM_ARCH_6ZK__) - /* Nothing in this object requires higher than v6. */ - .arch armv6 -#elif defined(__ARM_ARCH_6M__) -#ifdef ARM_RDP_MONITOR - /* Object file uses SVC, so mark as v6s-m. */ - .arch armv6s-m -#else - .arch armv6-m -#endif -#endif -#endif - -/* .text is used instead of .section .text so it works with arm-aout too. */ - .text - .syntax unified -#ifdef THUMB_V7_V6M - .thumb -.macro FUNC_START name - .global \name - .thumb_func -\name: -.endm -#else - .code 32 -.macro FUNC_START name - .global \name -\name: -.endm -#endif - -.macro indirect_call reg -#ifdef HAVE_CALL_INDIRECT - blx \reg -#else - mov lr, pc - mov pc, \reg -#endif -.endm - - .align 0 - - FUNC_START _mainCRTStartup - FUNC_START _start -#if defined(__ELF__) && !defined(__USING_SJLJ_EXCEPTIONS__) - /* Annotation for EABI unwinding tables. */ - .fnstart -#endif - - /* __ARM_ARCH_PROFILE is defined from GCC 4.8 onwards, however __ARM_ARCH_7A - has been defined since 4.2 onwards, which is when v7-a support was added - and hence 'A' profile support was added in the compiler. Allow for this - file to be built with older compilers. We only call this for A profile - cores. */ -#if defined (__ARM_ARCH_7A__) || (__ARM_ARCH_PROFILE == 'A') -/* The init hook does not use the stack and is called before the stack has been set up. */ -#ifdef ARM_RDI_MONITOR - bl _rdimon_hw_init_hook - .weak FUNCTION (_rdimon_hw_init_hook) -#endif -#endif - -/* Start by setting up a stack */ -#ifdef ARM_RDP_MONITOR - /* Issue Demon SWI to read stack info */ - swi SWI_GetEnv /* Returns command line in r0 */ - mov sp,r1 /* and the highest memory address in r1 */ - - /* stack limit is at end of data */ - /* allow slop for stack overflow handling and small frames */ -#ifdef __ARM_ARCH_6M__ - ldr r0, .LC2 - adds r0, #128 - adds r0, #128 - mov sl, r0 -#else - ldr sl, .LC2 - add sl, sl, #256 -#endif -#else -#ifdef ARM_RDI_MONITOR - /* Issue Angel SWI to read stack info */ - movs r0, #AngelSWI_Reason_HeapInfo - adr r1, .LC0 /* point at ptr to 4 words to receive data */ -#ifdef THUMB_V7M_V6M - bkpt AngelSWI -#elif defined(__thumb2__) - /* We are in thumb mode for startup on armv7 architectures. */ - AngelSWIAsm AngelSWI -#else - /* We are always in ARM mode for startup on pre armv7 archs. */ - AngelSWIAsm AngelSWI_ARM -#endif - ldr r0, .LC0 /* point at values read */ - - ldr r1, [r0, #0] - cmp r1, #0 - bne .LC32 - /* If the heap base value [r0, #0] is 0 then the heap base is actually - at the end of program data (i.e. __end__). See: - http://infocenter.arm.com/help/topic/com.arm.doc.dui0471-/Bacbefaa.html - for more information. */ - ldr r1, .LC31 - str r1, [r0, #0] -.LC32: - ldr r1, [r0, #8] - ldr r2, [r0, #12] - /* We skip setting sp/sl if 0 returned from semihosting. - - According to semihosting docs, if 0 returned from semihosting, - the system was unable to calculate the real value, so it's ok - to skip setting sp/sl to 0 here. - - Considering M-profile processors, We might want to initialize - sp by the first entry of vector table and return 0 to SYS_HEAPINFO - semihosting call, which will be skipped here. */ - cmp r1, #0 - beq .LC26 - mov sp, r1 -.LC26: - cmp r2, #0 - beq .LC27 - /* allow slop for stack overflow handling and small frames */ -#ifdef __ARM_ARCH_6M__ - adds r2, #128 - adds r2, #128 - mov sl, r2 -#else - add sl, r2, #256 -#endif -.LC27: -#else - /* Set up the stack pointer to a fixed value */ - /* Changes by toralf: - - Allow linker script to provide stack via __stack symbol - see - defintion of .Lstack - - Provide "hooks" that may be used by the application to add - custom init code - see .Lhwinit and .Lswinit - - Go through all execution modes and set up stack for each of them. - Loosely based on init.s from ARM/Motorola example code. - Note: Mode switch via CPSR is not allowed once in non-privileged - mode, so we take care not to enter "User" to set up its sp, - and also skip most operations if already in that mode. */ - - ldr r3, .Lstack - cmp r3, #0 -#ifdef __thumb2__ - it eq -#endif -#ifdef __ARM_ARCH_6M__ - bne .LC28 - ldr r3, .LC0 -.LC28: -#else - ldreq r3, .LC0 -#endif - /* Note: This 'mov' is essential when starting in User, and ensures we - always get *some* sp value for the initial mode, even if we - have somehow missed it below (in which case it gets the same - value as FIQ - not ideal, but better than nothing.) */ - mov sp, r3 -#ifdef THUMB_V7_V6M - /* XXX Fill in stack assignments for interrupt modes. */ -#else - mrs r2, CPSR - tst r2, #0x0F /* Test mode bits - in User of all are 0 */ - beq .LC23 /* "eq" means r2 AND #0x0F is 0 */ - msr CPSR_c, #0xD1 /* FIRQ mode, interrupts disabled */ - mov sp, r3 - sub sl, sp, #0x1000 /* This mode also has its own sl (see below) */ - - mov r3, sl - msr CPSR_c, #0xD7 /* Abort mode, interrupts disabled */ - mov sp, r3 - sub r3, r3, #0x1000 - - msr CPSR_c, #0xDB /* Undefined mode, interrupts disabled */ - mov sp, r3 - sub r3, r3, #0x1000 - - msr CPSR_c, #0xD2 /* IRQ mode, interrupts disabled */ - mov sp, r3 - sub r3, r3, #0x2000 - - msr CPSR_c, #0xD3 /* Supervisory mode, interrupts disabled */ - - mov sp, r3 - sub r3, r3, #0x8000 /* Min size 32k */ - bic r3, r3, #0x00FF /* Align with current 64k block */ - bic r3, r3, #0xFF00 - - str r3, [r3, #-4] /* Move value into user mode sp without */ - ldmdb r3, {sp}^ /* changing modes, via '^' form of ldm */ - orr r2, r2, #0xC0 /* Back to original mode, presumably SVC, */ - msr CPSR_c, r2 /* with FIQ/IRQ disable bits forced to 1 */ -#endif -.LC23: - /* Setup a default stack-limit in-case the code has been - compiled with "-mapcs-stack-check". Hard-wiring this value - is not ideal, since there is currently no support for - checking that the heap and stack have not collided, or that - this default 64k is enough for the program being executed. - However, it ensures that this simple crt0 world will not - immediately cause an overflow event: */ -#ifdef __ARM_ARCH_6M__ - movs r2, #64 - lsls r2, r2, #10 - subs r2, r3, r2 - mov sl, r2 -#else - sub sl, r3, #64 << 10 /* Still assumes 256bytes below sl */ -#endif -#endif -#endif - /* Zero the memory in the .bss section. */ - movs a2, #0 /* Second arg: fill value */ - mov fp, a2 /* Null frame pointer */ - mov r7, a2 /* Null frame pointer for Thumb */ - - ldr a1, .LC1 /* First arg: start of memory block */ - ldr a3, .LC2 - subs a3, a3, a1 /* Third arg: length of block */ - - -#if defined(__thumb__) && !defined(THUMB_V7_V6M) - /* Enter Thumb mode.... */ - add a4, pc, #1 /* Get the address of the Thumb block */ - bx a4 /* Go there and start Thumb decoding */ - - .code 16 - .global __change_mode - .thumb_func -__change_mode: -#endif - - bl FUNCTION (memset) -#if !defined (ARM_RDP_MONITOR) && !defined (ARM_RDI_MONITOR) -/* Changes by toralf: Taken from libgloss/m68k/crt0.S - * initialize target specific stuff. Only execute these - * functions it they exist. - */ - ldr r3, .Lhwinit - cmp r3, #0 - beq .LC24 - indirect_call r3 -.LC24: - ldr r3, .Lswinit - cmp r3, #0 - beq .LC25 - indirect_call r3 - -.LC25: - movs r0, #0 /* no arguments */ - movs r1, #0 /* no argv either */ -#else - /* Need to set up standard file handles */ - bl FUNCTION (initialise_monitor_handles) - -#ifdef ARM_RDP_MONITOR - swi SWI_GetEnv /* sets r0 to point to the command line */ - movs r1, r0 -#else - movs r0, #AngelSWI_Reason_GetCmdLine - adr r1, .LC30 /* Space for command line */ - AngelSWIAsm AngelSWI - ldr r1, .LC30 -#endif - /* Parse string at r1 */ - movs r0, #0 /* count of arguments so far */ - /* Push a NULL argument onto the end of the list. */ -#ifdef __thumb__ - push {r0} -#else - stmfd sp!, {r0} -#endif -.LC10: -/* Skip leading blanks */ -#ifdef __thumb__ - ldrb r3, [r1] - adds r1, #1 -#else - ldrb r3, [r1], #1 -#endif - cmp r3, #0 - beq .LC12 - cmp r3, #' ' - beq .LC10 - -/* See whether we are scanning a string */ - cmp r3, #'"' -#ifdef __thumb__ - beq .LC20 - cmp r3, #'\'' - bne .LC21 -.LC20: - movs r2, r3 - b .LC22 - -.LC21: - movs r2, #' ' /* terminator type */ - subs r1, r1, #1 /* adjust back to point at start char */ -.LC22: -#else - cmpne r3, #'\'' - moveq r2, r3 - movne r2, #' ' /* terminator type */ - subne r1, r1, #1 /* adjust back to point at start char */ -#endif - -/* Stack a pointer to the current argument */ -#ifdef __thumb__ - push {r1} -#else - stmfd sp!, {r1} -#endif - adds r0, r0, #1 -.LC11: -#ifdef __thumb__ - ldrb r3, [r1] - adds r1, #1 -#else - ldrb r3, [r1], #1 -#endif - cmp r3, #0 - beq .LC12 - cmp r2, r3 /* reached terminator? */ - bne .LC11 - movs r2, #0 - subs r3, r1, #1 - strb r2, [r3] /* terminate the arg string */ - b .LC10 - -.LC12: - mov r1, sp /* point at stacked arg pointers */ - /* We've now got the stacked args in order reverse the */ -#ifdef __thumb__ - movs r2, r0 - lsls r2, #2 - add r2, sp - mov r3, sp -.LC15: cmp r2, r3 - bls .LC14 - subs r2, #4 - ldr r4, [r2] - ldr r5, [r3] - str r5, [r2] - str r4, [r3] - adds r3, #4 - b .LC15 -.LC14: - /* Ensure doubleword stack alignment. */ - mov r4, sp - movs r5, #7 - bics r4, r5 - mov sp, r4 -#else - add r2, sp, r0, LSL #2 /* End of args */ - mov r3, sp /* Start of args */ -.LC13: cmp r2, r3 - ldrhi r4,[r2, #-4] /* Reverse ends of list */ - ldrhi r5, [r3] - strhi r5, [r2, #-4]! - strhi r4, [r3], #4 - bhi .LC13 - /* Ensure doubleword stack alignment. */ - bic sp, sp, #7 -#endif -#endif - -#ifdef __USES_INITFINI__ - /* Some arm/elf targets use the .init and .fini sections - to create constructors and destructors, and for these - targets we need to call the _init function and arrange - for _fini to be called at program exit. */ - movs r4, r0 - movs r5, r1 -#ifdef _LITE_EXIT - /* Make reference to atexit weak to avoid unconditionally pulling in - support code. Refer to comments in __atexit.c for more details. */ - .weak FUNCTION(atexit) - ldr r0, .Latexit - cmp r0, #0 - beq .Lweak_atexit -#endif - ldr r0, .Lfini - bl FUNCTION (atexit) -.Lweak_atexit: - bl FUNCTION (_init) - movs r0, r4 - movs r1, r5 -#endif - bl FUNCTION (main) - - bl FUNCTION (exit) /* Should not return. */ - -#if defined(__thumb__) && !defined(THUMB_V7_V6M) - /* Come out of Thumb mode. This code should be redundant. */ - - mov a4, pc - bx a4 - - .code 32 - .global change_back -change_back: - /* Halt the execution. This code should never be executed. */ - /* With no debug monitor, this probably aborts (eventually). - With a Demon debug monitor, this halts cleanly. - With an Angel debug monitor, this will report 'Unknown SWI'. */ - swi SWI_Exit -#endif - - /* For Thumb, constants must be after the code since only - positive offsets are supported for PC relative addresses. */ - - .align 0 -.LC0: -#ifdef ARM_RDI_MONITOR - .word HeapBase -#else -#ifndef ARM_RDP_MONITOR - /* Changes by toralf: Provide alternative "stack" variable whose value - may be defined externally; .Lstack will be used instead of .LC0 if - it points to a non-0 value. Also set up references to "hooks" that - may be used by the application to provide additional init code. */ - -#ifdef __pe__ - .word 0x800000 -#else - .word 0x80000 /* Top of RAM on the PIE board. */ -#endif -.Lstack: - .word __stack -.Lhwinit: - .word FUNCTION (hardware_init_hook) -.Lswinit: - .word FUNCTION (software_init_hook) - - /* Set up defaults for the above variables in the form of weak symbols - - so that application will link correctly, and get value 0 in - runtime (meaning "ignore setting") for the variables, when the user - does not provide the symbols. (The linker uses a weak symbol if, - and only if, a normal version of the same symbol isn't provided - e.g. by a linker script or another object file.) */ - - .weak __stack - .weak FUNCTION (hardware_init_hook) - .weak FUNCTION (software_init_hook) -#endif - -#endif -#if defined(__ELF__) && !defined(__USING_SJLJ_EXCEPTIONS__) - /* Protect against unhandled exceptions. */ - .cantunwind - .fnend -#endif -.LC1: - .word __bss_start__ -.LC2: - .word __bss_end__ -#ifdef __USES_INITFINI__ -#ifdef _LITE_EXIT -.Latexit: - .word FUNCTION(atexit) - - /* Weak reference _fini in case of lite exit. */ - .weak FUNCTION(_fini) -#endif -.Lfini: - .word FUNCTION(_fini) -#endif -#ifdef ARM_RDI_MONITOR -.LC30: - .word CommandLine - .word 255 -.LC31: - .word __end__ - -/* Workspace for Angel calls. */ - .data -/* Data returned by monitor SWI. */ -.global __stack_base__ -HeapBase: .word 0 -HeapLimit: .word 0 -__stack_base__: .word 0 -StackLimit: .word 0 -CommandLine: .space 256,0 /* Maximum length of 255 chars handled. */ -#endif - -#ifdef __pe__ - .section .idata$3 - .long 0,0,0,0,0,0,0,0 -#endif |