1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_LINKAGE_H 3 #define __ASM_LINKAGE_H 4 5 #define __ALIGN .align 2 6 #define __ALIGN_STR __stringify(__ALIGN) 7 8 #define SYM_FUNC_START(name) \ 9 SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) \ 10 .cfi_startproc; 11 12 #define SYM_FUNC_START_NOALIGN(name) \ 13 SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) \ 14 .cfi_startproc; 15 16 #define SYM_FUNC_START_LOCAL(name) \ 17 SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN) \ 18 .cfi_startproc; 19 20 #define SYM_FUNC_START_LOCAL_NOALIGN(name) \ 21 SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) \ 22 .cfi_startproc; 23 24 #define SYM_FUNC_START_WEAK(name) \ 25 SYM_START(name, SYM_L_WEAK, SYM_A_ALIGN) \ 26 .cfi_startproc; 27 28 #define SYM_FUNC_START_WEAK_NOALIGN(name) \ 29 SYM_START(name, SYM_L_WEAK, SYM_A_NONE) \ 30 .cfi_startproc; 31 32 #define SYM_FUNC_END(name) \ 33 .cfi_endproc; \ 34 SYM_END(name, SYM_T_FUNC) 35 36 #define SYM_CODE_START(name) \ 37 SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) \ 38 .cfi_startproc; 39 40 #define SYM_CODE_END(name) \ 41 .cfi_endproc; \ 42 SYM_END(name, SYM_T_NONE) 43 44 /* 45 * This is for the signal handler trampoline, which is used as the return 46 * address of the signal handlers in userspace instead of called normally. 47 * The long standing libgcc bug https://gcc.gnu.org/PR124050 requires a 48 * nop between .cfi_startproc and the actual address of the trampoline, so 49 * we cannot simply use SYM_FUNC_START. 50 * 51 * This wrapper also contains all the .cfi_* directives for recovering 52 * the content of the GPRs and the "return address" (where the rt_sigreturn 53 * syscall will jump to), assuming there is a struct rt_sigframe (where 54 * a struct sigcontext containing those information we need to recover) at 55 * $sp. The "DWARF for the LoongArch(TM) Architecture" manual states 56 * column 0 is for $zero, but it does not make too much sense to 57 * save/restore the hardware zero register. Repurpose this column here 58 * for the return address (here it's not the content of $ra we cannot use 59 * the default column 3). 60 */ 61 #define SYM_SIGFUNC_START(name) \ 62 .cfi_startproc; \ 63 .cfi_signal_frame; \ 64 .cfi_def_cfa 3, RT_SIGFRAME_SC; \ 65 .cfi_return_column 0; \ 66 .cfi_offset 0, SC_PC; \ 67 \ 68 .irp num, 1, 2, 3, 4, 5, 6, 7, 8, \ 69 9, 10, 11, 12, 13, 14, 15, 16, \ 70 17, 18, 19, 20, 21, 22, 23, 24, \ 71 25, 26, 27, 28, 29, 30, 31; \ 72 .cfi_offset \num, SC_REGS + \num * 8; \ 73 .endr; \ 74 \ 75 nop; \ 76 SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) 77 78 #define SYM_SIGFUNC_END(name) SYM_FUNC_END(name) 79 80 #endif 81