xref: /openbmc/linux/arch/arm64/kernel/perf_regs.c (revision 5b75a6af11357813a7eeb4a29d0261adbbfab556)
12ee0d7fdSJean Pihet #include <linux/errno.h>
22ee0d7fdSJean Pihet #include <linux/kernel.h>
32ee0d7fdSJean Pihet #include <linux/perf_event.h>
42ee0d7fdSJean Pihet #include <linux/bug.h>
5ff268ff7SMark Salter 
6ff268ff7SMark Salter #include <asm/compat.h>
72ee0d7fdSJean Pihet #include <asm/perf_regs.h>
82ee0d7fdSJean Pihet #include <asm/ptrace.h>
92ee0d7fdSJean Pihet 
102ee0d7fdSJean Pihet u64 perf_reg_value(struct pt_regs *regs, int idx)
112ee0d7fdSJean Pihet {
122ee0d7fdSJean Pihet 	if (WARN_ON_ONCE((u32)idx >= PERF_REG_ARM64_MAX))
132ee0d7fdSJean Pihet 		return 0;
142ee0d7fdSJean Pihet 
152ee0d7fdSJean Pihet 	/*
162ee0d7fdSJean Pihet 	 * Compat (i.e. 32 bit) mode:
172ee0d7fdSJean Pihet 	 * - PC has been set in the pt_regs struct in kernel_entry,
182ee0d7fdSJean Pihet 	 * - Handle SP and LR here.
192ee0d7fdSJean Pihet 	 */
202ee0d7fdSJean Pihet 	if (compat_user_mode(regs)) {
212ee0d7fdSJean Pihet 		if ((u32)idx == PERF_REG_ARM64_SP)
222ee0d7fdSJean Pihet 			return regs->compat_sp;
232ee0d7fdSJean Pihet 		if ((u32)idx == PERF_REG_ARM64_LR)
242ee0d7fdSJean Pihet 			return regs->compat_lr;
252ee0d7fdSJean Pihet 	}
262ee0d7fdSJean Pihet 
27*5b75a6afSWill Deacon 	if ((u32)idx == PERF_REG_ARM64_SP)
28*5b75a6afSWill Deacon 		return regs->sp;
29*5b75a6afSWill Deacon 
30*5b75a6afSWill Deacon 	if ((u32)idx == PERF_REG_ARM64_PC)
31*5b75a6afSWill Deacon 		return regs->pc;
32*5b75a6afSWill Deacon 
332ee0d7fdSJean Pihet 	return regs->regs[idx];
342ee0d7fdSJean Pihet }
352ee0d7fdSJean Pihet 
362ee0d7fdSJean Pihet #define REG_RESERVED (~((1ULL << PERF_REG_ARM64_MAX) - 1))
372ee0d7fdSJean Pihet 
382ee0d7fdSJean Pihet int perf_reg_validate(u64 mask)
392ee0d7fdSJean Pihet {
402ee0d7fdSJean Pihet 	if (!mask || mask & REG_RESERVED)
412ee0d7fdSJean Pihet 		return -EINVAL;
422ee0d7fdSJean Pihet 
432ee0d7fdSJean Pihet 	return 0;
442ee0d7fdSJean Pihet }
452ee0d7fdSJean Pihet 
462ee0d7fdSJean Pihet u64 perf_reg_abi(struct task_struct *task)
472ee0d7fdSJean Pihet {
482ee0d7fdSJean Pihet 	if (is_compat_thread(task_thread_info(task)))
492ee0d7fdSJean Pihet 		return PERF_SAMPLE_REGS_ABI_32;
502ee0d7fdSJean Pihet 	else
512ee0d7fdSJean Pihet 		return PERF_SAMPLE_REGS_ABI_64;
522ee0d7fdSJean Pihet }
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