xref: /linux/drivers/gpu/drm/xe/xe_guc_klv_helpers.c (revision 001821b0e79716c4e17c71d8e053a23599a7a508)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2024 Intel Corporation
4  */
5 
6 #include <linux/bitfield.h>
7 #include <drm/drm_print.h>
8 
9 #include "abi/guc_klvs_abi.h"
10 #include "xe_guc_klv_helpers.h"
11 
12 #define make_u64(hi, lo) ((u64)((u64)(u32)(hi) << 32 | (u32)(lo)))
13 
14 /**
15  * xe_guc_klv_key_to_string - Convert KLV key into friendly name.
16  * @key: the `GuC KLV`_ key
17  *
18  * Return: name of the KLV key.
19  */
20 const char *xe_guc_klv_key_to_string(u16 key)
21 {
22 	switch (key) {
23 	/* VGT POLICY keys */
24 	case GUC_KLV_VGT_POLICY_SCHED_IF_IDLE_KEY:
25 		return "sched_if_idle";
26 	case GUC_KLV_VGT_POLICY_ADVERSE_SAMPLE_PERIOD_KEY:
27 		return "sample_period";
28 	case GUC_KLV_VGT_POLICY_RESET_AFTER_VF_SWITCH_KEY:
29 		return "reset_engine";
30 	/* VF CFG keys */
31 	case GUC_KLV_VF_CFG_GGTT_START_KEY:
32 		return "ggtt_start";
33 	case GUC_KLV_VF_CFG_GGTT_SIZE_KEY:
34 		return "ggtt_size";
35 	case GUC_KLV_VF_CFG_LMEM_SIZE_KEY:
36 		return "lmem_size";
37 	case GUC_KLV_VF_CFG_NUM_CONTEXTS_KEY:
38 		return "num_contexts";
39 	case GUC_KLV_VF_CFG_TILE_MASK_KEY:
40 		return "tile_mask";
41 	case GUC_KLV_VF_CFG_NUM_DOORBELLS_KEY:
42 		return "num_doorbells";
43 	case GUC_KLV_VF_CFG_EXEC_QUANTUM_KEY:
44 		return "exec_quantum";
45 	case GUC_KLV_VF_CFG_PREEMPT_TIMEOUT_KEY:
46 		return "preempt_timeout";
47 	case GUC_KLV_VF_CFG_BEGIN_DOORBELL_ID_KEY:
48 		return "begin_db_id";
49 	case GUC_KLV_VF_CFG_BEGIN_CONTEXT_ID_KEY:
50 		return "begin_ctx_id";
51 	default:
52 		return "(unknown)";
53 	}
54 }
55 
56 /**
57  * xe_guc_klv_print - Print content of the buffer with `GuC KLV`_.
58  * @klvs: the buffer with KLVs
59  * @num_dwords: number of dwords (u32) available in the buffer
60  * @p: the &drm_printer
61  *
62  * The buffer may contain more than one KLV.
63  */
64 void xe_guc_klv_print(const u32 *klvs, u32 num_dwords, struct drm_printer *p)
65 {
66 	while (num_dwords >= GUC_KLV_LEN_MIN) {
67 		u32 key = FIELD_GET(GUC_KLV_0_KEY, klvs[0]);
68 		u32 len = FIELD_GET(GUC_KLV_0_LEN, klvs[0]);
69 
70 		klvs += GUC_KLV_LEN_MIN;
71 		num_dwords -= GUC_KLV_LEN_MIN;
72 
73 		if (num_dwords < len) {
74 			drm_printf(p, "{ key %#06x : truncated %zu of %zu bytes %*ph } # %s\n",
75 				   key, num_dwords * sizeof(u32), len * sizeof(u32),
76 				   (int)(num_dwords * sizeof(u32)), klvs,
77 				   xe_guc_klv_key_to_string(key));
78 			return;
79 		}
80 
81 		switch (len) {
82 		case 0:
83 			drm_printf(p, "{ key %#06x : no value } # %s\n",
84 				   key, xe_guc_klv_key_to_string(key));
85 			break;
86 		case 1:
87 			drm_printf(p, "{ key %#06x : 32b value %u } # %s\n",
88 				   key, klvs[0], xe_guc_klv_key_to_string(key));
89 			break;
90 		case 2:
91 			drm_printf(p, "{ key %#06x : 64b value %#llx } # %s\n",
92 				   key, make_u64(klvs[1], klvs[0]),
93 				   xe_guc_klv_key_to_string(key));
94 			break;
95 		default:
96 			drm_printf(p, "{ key %#06x : %zu bytes %*ph } # %s\n",
97 				   key, len * sizeof(u32), (int)(len * sizeof(u32)),
98 				   klvs, xe_guc_klv_key_to_string(key));
99 			break;
100 		}
101 
102 		klvs += len;
103 		num_dwords -= len;
104 	}
105 
106 	/* we don't expect any leftovers, fix if KLV header is ever changed */
107 	BUILD_BUG_ON(GUC_KLV_LEN_MIN > 1);
108 }
109 
110 /**
111  * xe_guc_klv_count - Count KLVs present in the buffer.
112  * @klvs: the buffer with KLVs
113  * @num_dwords: number of dwords (u32) in the buffer
114  *
115  * Return: number of recognized KLVs or
116  *         a negative error code if KLV buffer is truncated.
117  */
118 int xe_guc_klv_count(const u32 *klvs, u32 num_dwords)
119 {
120 	int num_klvs = 0;
121 
122 	while (num_dwords >= GUC_KLV_LEN_MIN) {
123 		u32 len = FIELD_GET(GUC_KLV_0_LEN, klvs[0]);
124 
125 		if (num_dwords < len + GUC_KLV_LEN_MIN)
126 			break;
127 
128 		klvs += GUC_KLV_LEN_MIN + len;
129 		num_dwords -= GUC_KLV_LEN_MIN + len;
130 		num_klvs++;
131 	}
132 
133 	return num_dwords ? -ENODATA : num_klvs;
134 }
135