xref: /openbmc/linux/arch/s390/include/asm/pai.h (revision 404e077a)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Processor Activity Instrumentation support for cryptography counters
4  *
5  *  Copyright IBM Corp. 2022
6  *  Author(s): Thomas Richter <tmricht@linux.ibm.com>
7  */
8 #ifndef _ASM_S390_PAI_H
9 #define _ASM_S390_PAI_H
10 
11 #include <linux/jump_label.h>
12 #include <asm/lowcore.h>
13 #include <asm/ptrace.h>
14 
15 struct qpaci_info_block {
16 	u64 header;
17 	struct {
18 		u64 : 8;
19 		u64 num_cc : 8;	/* # of supported crypto counters */
20 		u64 : 9;
21 		u64 num_nnpa : 7;	/* # of supported NNPA counters */
22 		u64 : 32;
23 	};
24 };
25 
26 static inline int qpaci(struct qpaci_info_block *info)
27 {
28 	/* Size of info (in double words minus one) */
29 	size_t size = sizeof(*info) / sizeof(u64) - 1;
30 	int cc;
31 
32 	asm volatile(
33 		"	lgr	0,%[size]\n"
34 		"	.insn	s,0xb28f0000,%[info]\n"
35 		"	lgr	%[size],0\n"
36 		"	ipm	%[cc]\n"
37 		"	srl	%[cc],28\n"
38 		: [cc] "=d" (cc), [info] "=Q" (*info), [size] "+&d" (size)
39 		:
40 		: "0", "cc", "memory");
41 	return cc ? (size + 1) * sizeof(u64) : 0;
42 }
43 
44 #define PAI_CRYPTO_BASE			0x1000	/* First event number */
45 #define PAI_CRYPTO_MAXCTR		256	/* Max # of event counters */
46 #define PAI_CRYPTO_KERNEL_OFFSET	2048
47 #define PAI_NNPA_BASE			0x1800	/* First event number */
48 #define PAI_NNPA_MAXCTR			128	/* Max # of event counters */
49 
50 DECLARE_STATIC_KEY_FALSE(pai_key);
51 
52 static __always_inline void pai_kernel_enter(struct pt_regs *regs)
53 {
54 	if (!IS_ENABLED(CONFIG_PERF_EVENTS))
55 		return;
56 	if (!static_branch_unlikely(&pai_key))
57 		return;
58 	if (!S390_lowcore.ccd)
59 		return;
60 	if (!user_mode(regs))
61 		return;
62 	WRITE_ONCE(S390_lowcore.ccd, S390_lowcore.ccd | PAI_CRYPTO_KERNEL_OFFSET);
63 }
64 
65 static __always_inline void pai_kernel_exit(struct pt_regs *regs)
66 {
67 	if (!IS_ENABLED(CONFIG_PERF_EVENTS))
68 		return;
69 	if (!static_branch_unlikely(&pai_key))
70 		return;
71 	if (!S390_lowcore.ccd)
72 		return;
73 	if (!user_mode(regs))
74 		return;
75 	WRITE_ONCE(S390_lowcore.ccd, S390_lowcore.ccd & ~PAI_CRYPTO_KERNEL_OFFSET);
76 }
77 
78 enum paievt_mode {
79 	PAI_MODE_NONE,
80 	PAI_MODE_SAMPLING,
81 	PAI_MODE_COUNTING,
82 };
83 
84 #endif
85