xref: /linux/tools/perf/util/arm-spe-decoder/arm-spe-decoder.c (revision 8cf4d17ec7f0bebff8f3de3131e0c7e422a36da6)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * arm_spe_decoder.c: ARM SPE support
4  */
5 
6 #ifndef _GNU_SOURCE
7 #define _GNU_SOURCE
8 #endif
9 #include <errno.h>
10 #include <inttypes.h>
11 #include <stdbool.h>
12 #include <string.h>
13 #include <stdint.h>
14 #include <stdlib.h>
15 #include <linux/bitops.h>
16 #include <linux/compiler.h>
17 #include <linux/zalloc.h>
18 
19 #include "../auxtrace.h"
20 #include "../debug.h"
21 #include "../util.h"
22 
23 #include "arm-spe-decoder.h"
24 
25 static u64 arm_spe_calc_ip(int index, u64 payload)
26 {
27 	u64 ns, el, val;
28 
29 	/* Instruction virtual address or Branch target address */
30 	if (index == SPE_ADDR_PKT_HDR_INDEX_INS ||
31 	    index == SPE_ADDR_PKT_HDR_INDEX_BRANCH ||
32 	    index == SPE_ADDR_PKT_HDR_INDEX_PREV_BRANCH) {
33 		ns = SPE_ADDR_PKT_GET_NS(payload);
34 		el = SPE_ADDR_PKT_GET_EL(payload);
35 
36 		/* Clean highest byte */
37 		payload = SPE_ADDR_PKT_ADDR_GET_BYTES_0_6(payload);
38 
39 		/* Fill highest byte for EL1 or EL2 (VHE) mode */
40 		if (ns && (el == SPE_ADDR_PKT_EL1 || el == SPE_ADDR_PKT_EL2))
41 			payload |= 0xffULL << SPE_ADDR_PKT_ADDR_BYTE7_SHIFT;
42 
43 	/* Data access virtual address */
44 	} else if (index == SPE_ADDR_PKT_HDR_INDEX_DATA_VIRT) {
45 
46 		/* Clean tags */
47 		payload = SPE_ADDR_PKT_ADDR_GET_BYTES_0_6(payload);
48 
49 		/*
50 		 * Armv8 ARM (ARM DDI 0487F.c), chapter "D10.2.1 Address packet"
51 		 * defines the data virtual address payload format, the top byte
52 		 * (bits [63:56]) is assigned as top-byte tag; so we only can
53 		 * retrieve address value from bits [55:0].
54 		 *
55 		 * According to Documentation/arch/arm64/memory.rst, if detects the
56 		 * specific pattern in bits [55:52] of payload which falls in
57 		 * the kernel space, should fixup the top byte and this allows
58 		 * perf tool to parse DSO symbol for data address correctly.
59 		 *
60 		 * For this reason, if detects the bits [55:52] is 0xf, will
61 		 * fill 0xff into the top byte.
62 		 */
63 		val = SPE_ADDR_PKT_ADDR_GET_BYTE_6(payload);
64 		if ((val & 0xf0ULL) == 0xf0ULL)
65 			payload |= 0xffULL << SPE_ADDR_PKT_ADDR_BYTE7_SHIFT;
66 
67 	/* Data access physical address */
68 	} else if (index == SPE_ADDR_PKT_HDR_INDEX_DATA_PHYS) {
69 		/* Clean highest byte */
70 		payload = SPE_ADDR_PKT_ADDR_GET_BYTES_0_6(payload);
71 	} else {
72 		static u32 seen_idx = 0;
73 		if (!(seen_idx & BIT(index))) {
74 			seen_idx |= BIT(index);
75 			pr_warning("ignoring unsupported address packet index: 0x%x\n", index);
76 		}
77 	}
78 
79 	return payload;
80 }
81 
82 struct arm_spe_decoder *arm_spe_decoder_new(struct arm_spe_params *params)
83 {
84 	struct arm_spe_decoder *decoder;
85 
86 	if (!params->get_trace)
87 		return NULL;
88 
89 	decoder = zalloc(sizeof(struct arm_spe_decoder));
90 	if (!decoder)
91 		return NULL;
92 
93 	decoder->get_trace = params->get_trace;
94 	decoder->data = params->data;
95 
96 	return decoder;
97 }
98 
99 void arm_spe_decoder_free(struct arm_spe_decoder *decoder)
100 {
101 	free(decoder);
102 }
103 
104 static int arm_spe_get_data(struct arm_spe_decoder *decoder)
105 {
106 	struct arm_spe_buffer buffer = { .buf = 0, };
107 	int ret;
108 
109 	pr_debug("Getting more data\n");
110 	ret = decoder->get_trace(&buffer, decoder->data);
111 	if (ret < 0)
112 		return ret;
113 
114 	decoder->buf = buffer.buf;
115 	decoder->len = buffer.len;
116 
117 	if (!decoder->len)
118 		pr_debug("No more data\n");
119 
120 	return decoder->len;
121 }
122 
123 static int arm_spe_get_next_packet(struct arm_spe_decoder *decoder,
124 				  struct arm_spe_pkt *packet)
125 {
126 	int ret;
127 
128 	do {
129 		if (!decoder->len) {
130 			ret = arm_spe_get_data(decoder);
131 
132 			/* Failed to read out trace data */
133 			if (ret <= 0)
134 				return ret;
135 		}
136 
137 		ret = arm_spe_get_packet(decoder->buf, decoder->len,
138 					 packet, decoder->midr);
139 
140 		if (ret <= 0) {
141 			/* Move forward for 1 byte */
142 			decoder->buf += 1;
143 			decoder->len -= 1;
144 			return -EBADMSG;
145 		}
146 
147 		decoder->buf += ret;
148 		decoder->len -= ret;
149 	} while (packet->type == ARM_SPE_PAD);
150 
151 	return 1;
152 }
153 
154 static int arm_spe_read_record(struct arm_spe_decoder *decoder)
155 {
156 	int err;
157 	int idx;
158 	u64 payload, ip;
159 	struct arm_spe_pkt packet;
160 
161 	memset(&decoder->record, 0x0, sizeof(decoder->record));
162 	decoder->record.context_id = (u64)-1;
163 
164 	while (1) {
165 		err = arm_spe_get_next_packet(decoder, &packet);
166 		if (err <= 0)
167 			return err;
168 
169 		idx = packet.index;
170 		payload = packet.payload;
171 
172 		switch (packet.type) {
173 		case ARM_SPE_TIMESTAMP:
174 			decoder->record.timestamp = payload;
175 			return 1;
176 		case ARM_SPE_END:
177 			return 1;
178 		case ARM_SPE_ADDRESS:
179 			ip = arm_spe_calc_ip(idx, payload);
180 			if (idx == SPE_ADDR_PKT_HDR_INDEX_INS)
181 				decoder->record.from_ip = ip;
182 			else if (idx == SPE_ADDR_PKT_HDR_INDEX_BRANCH)
183 				decoder->record.to_ip = ip;
184 			else if (idx == SPE_ADDR_PKT_HDR_INDEX_DATA_VIRT)
185 				decoder->record.virt_addr = ip;
186 			else if (idx == SPE_ADDR_PKT_HDR_INDEX_DATA_PHYS)
187 				decoder->record.phys_addr = ip;
188 			else if (idx == SPE_ADDR_PKT_HDR_INDEX_PREV_BRANCH)
189 				decoder->record.prev_br_tgt = ip;
190 			break;
191 		case ARM_SPE_COUNTER:
192 			if (idx == SPE_CNT_PKT_HDR_INDEX_TOTAL_LAT)
193 				decoder->record.latency = payload;
194 			break;
195 		case ARM_SPE_CONTEXT:
196 			decoder->record.context_id = payload;
197 			break;
198 		case ARM_SPE_OP_TYPE:
199 			switch (idx) {
200 			case SPE_OP_PKT_HDR_CLASS_LD_ST_ATOMIC:
201 				decoder->record.op |= ARM_SPE_OP_LDST;
202 				if (payload & SPE_OP_PKT_ST)
203 					decoder->record.op |= ARM_SPE_OP_ST;
204 				else
205 					decoder->record.op |= ARM_SPE_OP_LD;
206 
207 				if (SPE_OP_PKT_LDST_SUBCLASS_GP_REG(payload)) {
208 					decoder->record.op |= ARM_SPE_OP_GP_REG;
209 				} else if (SPE_OP_PKT_LDST_SUBCLASS_SIMD_FP(payload)) {
210 					decoder->record.op |= ARM_SPE_OP_SIMD_FP;
211 				} else if (SPE_OP_PKT_LDST_SUBCLASS_UNSPEC_REG(payload)) {
212 					decoder->record.op |= ARM_SPE_OP_UNSPEC_REG;
213 				} else if (SPE_OP_PKT_LDST_SUBCLASS_NV_SYSREG(payload)) {
214 					decoder->record.op |= ARM_SPE_OP_NV_SYSREG;
215 				} else if (SPE_OP_PKT_LDST_SUBCLASS_MTE_TAG(payload)) {
216 					decoder->record.op |= ARM_SPE_OP_MTE_TAG;
217 				} else if (SPE_OP_PKT_LDST_SUBCLASS_EXTENDED(payload)) {
218 					if (payload & SPE_OP_PKT_AR)
219 						decoder->record.op |= ARM_SPE_OP_AR;
220 					if (payload & SPE_OP_PKT_EXCL)
221 						decoder->record.op |= ARM_SPE_OP_EXCL;
222 					if (payload & SPE_OP_PKT_AT)
223 						decoder->record.op |= ARM_SPE_OP_ATOMIC;
224 				} else if (SPE_OP_PKT_LDST_SUBCLASS_SVE_SME_REG(payload)) {
225 					decoder->record.op |= ARM_SPE_OP_SVE;
226 					if (payload & SPE_OP_PKT_SVE_PRED)
227 						decoder->record.op |= ARM_SPE_OP_PRED;
228 					if (payload & SPE_OP_PKT_SVE_SG)
229 						decoder->record.op |= ARM_SPE_OP_SG;
230 				} else if (SPE_OP_PKT_LDST_SUBCLASS_MEMCPY(payload)) {
231 					decoder->record.op |= ARM_SPE_OP_MEMCPY;
232 				} else if (SPE_OP_PKT_LDST_SUBCLASS_MEMSET(payload)) {
233 					decoder->record.op |= ARM_SPE_OP_MEMSET;
234 				} else if (SPE_OP_PKT_LDST_SUBCLASS_GCS(payload)) {
235 					decoder->record.op |= ARM_SPE_OP_GCS;
236 					if (payload & SPE_OP_PKT_GCS_COMM)
237 						decoder->record.op |= ARM_SPE_OP_COMM;
238 				}
239 
240 				break;
241 			case SPE_OP_PKT_HDR_CLASS_OTHER:
242 				decoder->record.op |= ARM_SPE_OP_OTHER;
243 				if (SPE_OP_PKT_OTHER_SUBCLASS_SVE(payload)) {
244 					decoder->record.op |= ARM_SPE_OP_SVE | ARM_SPE_OP_DP;
245 					if (payload & SPE_OP_PKT_OTHER_FP)
246 						decoder->record.op |= ARM_SPE_OP_FP;
247 					if (payload & SPE_OP_PKT_SVE_PRED)
248 						decoder->record.op |= ARM_SPE_OP_PRED;
249 				} else if (SPE_OP_PKT_OTHER_SUBCLASS_SME(payload)) {
250 					decoder->record.op |= ARM_SPE_OP_SME;
251 					if (payload & SPE_OP_PKT_OTHER_FP)
252 						decoder->record.op |= ARM_SPE_OP_FP;
253 				} else if (SPE_OP_PKT_OTHER_SUBCLASS_OTHER(payload)) {
254 					if (payload & SPE_OP_PKT_OTHER_ASE)
255 						decoder->record.op |= ARM_SPE_OP_ASE;
256 					if (payload & SPE_OP_PKT_OTHER_FP)
257 						decoder->record.op |= ARM_SPE_OP_FP;
258 					if (payload & SPE_OP_PKT_COND)
259 						decoder->record.op |= ARM_SPE_OP_COND;
260 				}
261 				break;
262 			case SPE_OP_PKT_HDR_CLASS_BR_ERET:
263 				decoder->record.op |= ARM_SPE_OP_BRANCH_ERET;
264 				if (payload & SPE_OP_PKT_COND)
265 					decoder->record.op |= ARM_SPE_OP_BR_COND;
266 				if (payload & SPE_OP_PKT_INDIRECT_BRANCH)
267 					decoder->record.op |= ARM_SPE_OP_BR_INDIRECT;
268 				if (payload & SPE_OP_PKT_GCS)
269 					decoder->record.op |= ARM_SPE_OP_BR_GCS;
270 				if (SPE_OP_PKT_CR_BL(payload))
271 					decoder->record.op |= ARM_SPE_OP_BR_CR_BL;
272 				if (SPE_OP_PKT_CR_RET(payload))
273 					decoder->record.op |= ARM_SPE_OP_BR_CR_RET;
274 				if (SPE_OP_PKT_CR_NON_BL_RET(payload))
275 					decoder->record.op |= ARM_SPE_OP_BR_CR_NON_BL_RET;
276 				break;
277 			default:
278 				pr_err("Get packet error!\n");
279 				return -1;
280 			}
281 			break;
282 		case ARM_SPE_EVENTS:
283 			decoder->record.type = payload;
284 			break;
285 		case ARM_SPE_DATA_SOURCE:
286 			decoder->record.source = payload;
287 			break;
288 		case ARM_SPE_BAD:
289 			break;
290 		case ARM_SPE_PAD:
291 			break;
292 		default:
293 			pr_err("Get packet error!\n");
294 			return -1;
295 		}
296 	}
297 
298 	return 0;
299 }
300 
301 int arm_spe_decode(struct arm_spe_decoder *decoder)
302 {
303 	return arm_spe_read_record(decoder);
304 }
305