18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */ 28c2ecf20Sopenharmony_ci#include <linux/linkage.h> 38c2ecf20Sopenharmony_ci 48c2ecf20Sopenharmony_ci#define R0 0x00 58c2ecf20Sopenharmony_ci#define R1 0x08 68c2ecf20Sopenharmony_ci#define R2 0x10 78c2ecf20Sopenharmony_ci#define R3 0x18 88c2ecf20Sopenharmony_ci#define R4 0x20 98c2ecf20Sopenharmony_ci#define R5 0x28 108c2ecf20Sopenharmony_ci#define R6 0x30 118c2ecf20Sopenharmony_ci#define R7 0x38 128c2ecf20Sopenharmony_ci#define R8 0x40 138c2ecf20Sopenharmony_ci#define R9 0x48 148c2ecf20Sopenharmony_ci#define SL 0x50 158c2ecf20Sopenharmony_ci#define FP 0x58 168c2ecf20Sopenharmony_ci#define IP 0x60 178c2ecf20Sopenharmony_ci#define SP 0x68 188c2ecf20Sopenharmony_ci#define LR 0x70 198c2ecf20Sopenharmony_ci#define PC 0x78 208c2ecf20Sopenharmony_ci 218c2ecf20Sopenharmony_ci/* 228c2ecf20Sopenharmony_ci * Implementation of void perf_regs_load(u64 *regs); 238c2ecf20Sopenharmony_ci * 248c2ecf20Sopenharmony_ci * This functions fills in the 'regs' buffer from the actual registers values, 258c2ecf20Sopenharmony_ci * in the way the perf built-in unwinding test expects them: 268c2ecf20Sopenharmony_ci * - the PC at the time at the call to this function. Since this function 278c2ecf20Sopenharmony_ci * is called using a bl instruction, the PC value is taken from LR. 288c2ecf20Sopenharmony_ci * The built-in unwinding test then unwinds the call stack from the dwarf 298c2ecf20Sopenharmony_ci * information in unwind__get_entries. 308c2ecf20Sopenharmony_ci * 318c2ecf20Sopenharmony_ci * Notes: 328c2ecf20Sopenharmony_ci * - the 8 bytes stride in the registers offsets comes from the fact 338c2ecf20Sopenharmony_ci * that the registers are stored in an u64 array (u64 *regs), 348c2ecf20Sopenharmony_ci * - the regs buffer needs to be zeroed before the call to this function, 358c2ecf20Sopenharmony_ci * in this case using a calloc in dwarf-unwind.c. 368c2ecf20Sopenharmony_ci */ 378c2ecf20Sopenharmony_ci 388c2ecf20Sopenharmony_ci.text 398c2ecf20Sopenharmony_ci.type perf_regs_load,%function 408c2ecf20Sopenharmony_ciSYM_FUNC_START(perf_regs_load) 418c2ecf20Sopenharmony_ci str r0, [r0, #R0] 428c2ecf20Sopenharmony_ci str r1, [r0, #R1] 438c2ecf20Sopenharmony_ci str r2, [r0, #R2] 448c2ecf20Sopenharmony_ci str r3, [r0, #R3] 458c2ecf20Sopenharmony_ci str r4, [r0, #R4] 468c2ecf20Sopenharmony_ci str r5, [r0, #R5] 478c2ecf20Sopenharmony_ci str r6, [r0, #R6] 488c2ecf20Sopenharmony_ci str r7, [r0, #R7] 498c2ecf20Sopenharmony_ci str r8, [r0, #R8] 508c2ecf20Sopenharmony_ci str r9, [r0, #R9] 518c2ecf20Sopenharmony_ci str sl, [r0, #SL] 528c2ecf20Sopenharmony_ci str fp, [r0, #FP] 538c2ecf20Sopenharmony_ci str ip, [r0, #IP] 548c2ecf20Sopenharmony_ci str sp, [r0, #SP] 558c2ecf20Sopenharmony_ci str lr, [r0, #LR] 568c2ecf20Sopenharmony_ci str lr, [r0, #PC] // store pc as lr in order to skip the call 578c2ecf20Sopenharmony_ci // to this function 588c2ecf20Sopenharmony_ci mov pc, lr 598c2ecf20Sopenharmony_ciSYM_FUNC_END(perf_regs_load) 60