| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| #include "textflag.h" |
| |
| TEXT _rt0_arm_linux(SB),NOSPLIT,$-4 |
| MOVW (R13), R0 // argc |
| MOVW $4(R13), R1 // argv |
| MOVW $_rt0_arm_linux1(SB), R4 |
| B (R4) |
| |
| // When building with -buildmode=c-shared, this symbol is called when the shared |
| // library is loaded. |
| TEXT _rt0_arm_linux_lib(SB),NOSPLIT,$104 |
| // Preserve callee-save registers. Raspberry Pi's dlopen(), for example, |
| // actually cares that R11 is preserved. |
| MOVW R4, 12(R13) |
| MOVW R5, 16(R13) |
| MOVW R6, 20(R13) |
| MOVW R7, 24(R13) |
| MOVW R8, 28(R13) |
| MOVW R11, 32(R13) |
| |
| // Skip floating point registers on GOARM < 6. |
| MOVB runtime·goarm(SB), R11 |
| CMP $6, R11 |
| BLT skipfpsave |
| MOVD F8, (32+8*1)(R13) |
| MOVD F9, (32+8*2)(R13) |
| MOVD F10, (32+8*3)(R13) |
| MOVD F11, (32+8*4)(R13) |
| MOVD F12, (32+8*5)(R13) |
| MOVD F13, (32+8*6)(R13) |
| MOVD F14, (32+8*7)(R13) |
| MOVD F15, (32+8*8)(R13) |
| skipfpsave: |
| // Save argc/argv. |
| MOVW R0, _rt0_arm_linux_lib_argc<>(SB) |
| MOVW R1, _rt0_arm_linux_lib_argv<>(SB) |
| |
| // Synchronous initialization. |
| MOVW $runtime·libpreinit(SB), R2 |
| CALL (R2) |
| |
| // Create a new thread to do the runtime initialization. |
| MOVW _cgo_sys_thread_create(SB), R2 |
| CMP $0, R2 |
| BEQ nocgo |
| MOVW $_rt0_arm_linux_lib_go<>(SB), R0 |
| MOVW $0, R1 |
| BL (R2) |
| B rr |
| nocgo: |
| MOVW $0x800000, R0 // stacksize = 8192KB |
| MOVW $_rt0_arm_linux_lib_go<>(SB), R1 // fn |
| MOVW R0, 4(R13) |
| MOVW R1, 8(R13) |
| BL runtime·newosproc0(SB) |
| rr: |
| // Restore callee-save registers and return. |
| MOVB runtime·goarm(SB), R11 |
| CMP $6, R11 |
| BLT skipfprest |
| MOVD (32+8*1)(R13), F8 |
| MOVD (32+8*2)(R13), F9 |
| MOVD (32+8*3)(R13), F10 |
| MOVD (32+8*4)(R13), F11 |
| MOVD (32+8*5)(R13), F12 |
| MOVD (32+8*6)(R13), F13 |
| MOVD (32+8*7)(R13), F14 |
| MOVD (32+8*8)(R13), F15 |
| skipfprest: |
| MOVW 12(R13), R4 |
| MOVW 16(R13), R5 |
| MOVW 20(R13), R6 |
| MOVW 24(R13), R7 |
| MOVW 28(R13), R8 |
| MOVW 32(R13), R11 |
| RET |
| |
| TEXT _rt0_arm_linux_lib_go<>(SB),NOSPLIT,$8 |
| MOVW _rt0_arm_linux_lib_argc<>(SB), R0 |
| MOVW _rt0_arm_linux_lib_argv<>(SB), R1 |
| MOVW R0, 0(R13) |
| MOVW R1, 4(R13) |
| B runtime·rt0_go(SB) |
| |
| DATA _rt0_arm_linux_lib_argc<>(SB)/4,$0 |
| GLOBL _rt0_arm_linux_lib_argc<>(SB),NOPTR,$4 |
| DATA _rt0_arm_linux_lib_argv<>(SB)/4,$0 |
| GLOBL _rt0_arm_linux_lib_argv<>(SB),NOPTR,$4 |
| |
| TEXT _rt0_arm_linux1(SB),NOSPLIT,$-4 |
| // We first need to detect the kernel ABI, and warn the user |
| // if the system only supports OABI |
| // The strategy here is to call some EABI syscall to see if |
| // SIGILL is received. |
| // To catch SIGILL, we have to first setup sigaction, this is |
| // a chicken-and-egg problem, because we can't do syscall if |
| // we don't know the kernel ABI... Oh, not really, we can do |
| // syscall in Thumb mode. |
| |
| // Save argc and argv |
| MOVM.DB.W [R0-R1], (R13) |
| |
| // Thumb mode OABI check disabled because there are some |
| // EABI systems that do not support Thumb execution. |
| // We can run on them except for this check! |
| |
| // // set up sa_handler |
| // MOVW $bad_abi<>(SB), R0 // sa_handler |
| // MOVW $0, R1 // sa_flags |
| // MOVW $0, R2 // sa_restorer |
| // MOVW $0, R3 // sa_mask |
| // MOVM.DB.W [R0-R3], (R13) |
| // MOVW $4, R0 // SIGILL |
| // MOVW R13, R1 // sa |
| // SUB $16, R13 |
| // MOVW R13, R2 // old_sa |
| // MOVW $8, R3 // c |
| // MOVW $174, R7 // sys_sigaction |
| // BL oabi_syscall<>(SB) |
| |
| // do an EABI syscall |
| MOVW $20, R7 // sys_getpid |
| SWI $0 // this will trigger SIGILL on OABI systems |
| |
| // MOVW $4, R0 // SIGILL |
| // MOVW R13, R1 // sa |
| // MOVW $0, R2 // old_sa |
| // MOVW $8, R3 // c |
| // MOVW $174, R7 // sys_sigaction |
| // SWI $0 // restore signal handler |
| // ADD $32, R13 |
| |
| B runtime·rt0_go(SB) |
| |
| TEXT bad_abi<>(SB),NOSPLIT,$-4 |
| // give diagnosis and exit |
| MOVW $2, R0 // stderr |
| MOVW $bad_abi_msg(SB), R1 // data |
| MOVW $45, R2 // len |
| MOVW $4, R7 // sys_write |
| BL oabi_syscall<>(SB) |
| MOVW $1, R0 |
| MOVW $1, R7 // sys_exit |
| BL oabi_syscall<>(SB) |
| B 0(PC) |
| |
| DATA bad_abi_msg+0x00(SB)/8, $"This pro" |
| DATA bad_abi_msg+0x08(SB)/8, $"gram can" |
| DATA bad_abi_msg+0x10(SB)/8, $" only be" |
| DATA bad_abi_msg+0x18(SB)/8, $" run on " |
| DATA bad_abi_msg+0x20(SB)/8, $"EABI ker" |
| DATA bad_abi_msg+0x28(SB)/4, $"nels" |
| DATA bad_abi_msg+0x2c(SB)/1, $0xa |
| GLOBL bad_abi_msg(SB), RODATA, $45 |
| |
| TEXT oabi_syscall<>(SB),NOSPLIT,$-4 |
| ADD $1, R15, R4 // R15 is hardware PC |
| WORD $0xe12fff14 //BX (R4) // enter thumb mode |
| // TODO(minux): only supports little-endian CPUs |
| WORD $0x4770df01 // swi $1; bx lr |
| |
| TEXT main(SB),NOSPLIT,$-4 |
| MOVW $_rt0_arm_linux1(SB), R4 |
| B (R4) |
| |
