summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/riscv/rhct.c
blob: caa2c16e16974a6c76961240c08df8fbe4d598e1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2022-2023, Ventana Micro Systems Inc
 *	Author: Sunil V L <sunilvl@ventanamicro.com>
 *
 */

#define pr_fmt(fmt)     "ACPI: RHCT: " fmt

#include <linux/acpi.h>
#include <linux/bits.h>

static struct acpi_table_rhct *acpi_get_rhct(void)
{
	static struct acpi_table_header *rhct;
	acpi_status status;

	/*
	 * RHCT will be used at runtime on every CPU, so we
	 * don't need to call acpi_put_table() to release the table mapping.
	 */
	if (!rhct) {
		status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct);
		if (ACPI_FAILURE(status)) {
			pr_warn_once("No RHCT table found\n");
			return NULL;
		}
	}

	return (struct acpi_table_rhct *)rhct;
}

/*
 * During early boot, the caller should call acpi_get_table() and pass its pointer to
 * these functions(and free up later). At run time, since this table can be used
 * multiple times, NULL may be passed in order to use the cached table.
 */
int acpi_get_riscv_isa(struct acpi_table_header *table, unsigned int cpu, const char **isa)
{
	struct acpi_rhct_node_header *node, *ref_node, *end;
	u32 size_hdr = sizeof(struct acpi_rhct_node_header);
	u32 size_hartinfo = sizeof(struct acpi_rhct_hart_info);
	struct acpi_rhct_hart_info *hart_info;
	struct acpi_rhct_isa_string *isa_node;
	struct acpi_table_rhct *rhct;
	u32 *hart_info_node_offset;
	u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu);

	BUG_ON(acpi_disabled);

	if (!table) {
		rhct = acpi_get_rhct();
		if (!rhct)
			return -ENOENT;
	} else {
		rhct = (struct acpi_table_rhct *)table;
	}

	end = ACPI_ADD_PTR(struct acpi_rhct_node_header, rhct, rhct->header.length);

	for (node = ACPI_ADD_PTR(struct acpi_rhct_node_header, rhct, rhct->node_offset);
	     node < end;
	     node = ACPI_ADD_PTR(struct acpi_rhct_node_header, node, node->length)) {
		if (node->type == ACPI_RHCT_NODE_TYPE_HART_INFO) {
			hart_info = ACPI_ADD_PTR(struct acpi_rhct_hart_info, node, size_hdr);
			hart_info_node_offset = ACPI_ADD_PTR(u32, hart_info, size_hartinfo);
			if (acpi_cpu_id != hart_info->uid)
				continue;

			for (int i = 0; i < hart_info->num_offsets; i++) {
				ref_node = ACPI_ADD_PTR(struct acpi_rhct_node_header,
							rhct, hart_info_node_offset[i]);
				if (ref_node->type == ACPI_RHCT_NODE_TYPE_ISA_STRING) {
					isa_node = ACPI_ADD_PTR(struct acpi_rhct_isa_string,
								ref_node, size_hdr);
					*isa = isa_node->isa;
					return 0;
				}
			}
		}
	}

	return -1;
}

static void acpi_parse_hart_info_cmo_node(struct acpi_table_rhct *rhct,
					  struct acpi_rhct_hart_info *hart_info,
					  u32 *cbom_size, u32 *cboz_size, u32 *cbop_size)
{
	u32 size_hartinfo = sizeof(struct acpi_rhct_hart_info);
	u32 size_hdr = sizeof(struct acpi_rhct_node_header);
	struct acpi_rhct_node_header *ref_node;
	struct acpi_rhct_cmo_node *cmo_node;
	u32 *hart_info_node_offset;

	hart_info_node_offset = ACPI_ADD_PTR(u32, hart_info, size_hartinfo);
	for (int i = 0; i < hart_info->num_offsets; i++) {
		ref_node = ACPI_ADD_PTR(struct acpi_rhct_node_header,
					rhct, hart_info_node_offset[i]);
		if (ref_node->type == ACPI_RHCT_NODE_TYPE_CMO) {
			cmo_node = ACPI_ADD_PTR(struct acpi_rhct_cmo_node,
						ref_node, size_hdr);
			if (cbom_size && cmo_node->cbom_size <= 30) {
				if (!*cbom_size)
					*cbom_size = BIT(cmo_node->cbom_size);
				else if (*cbom_size != BIT(cmo_node->cbom_size))
					pr_warn("CBOM size is not the same across harts\n");
			}

			if (cboz_size && cmo_node->cboz_size <= 30) {
				if (!*cboz_size)
					*cboz_size = BIT(cmo_node->cboz_size);
				else if (*cboz_size != BIT(cmo_node->cboz_size))
					pr_warn("CBOZ size is not the same across harts\n");
			}

			if (cbop_size && cmo_node->cbop_size <= 30) {
				if (!*cbop_size)
					*cbop_size = BIT(cmo_node->cbop_size);
				else if (*cbop_size != BIT(cmo_node->cbop_size))
					pr_warn("CBOP size is not the same across harts\n");
			}
		}
	}
}

/*
 * During early boot, the caller should call acpi_get_table() and pass its pointer to
 * these functions (and free up later). At run time, since this table can be used
 * multiple times, pass NULL so that the table remains in memory.
 */
void acpi_get_cbo_block_size(struct acpi_table_header *table, u32 *cbom_size,
			     u32 *cboz_size, u32 *cbop_size)
{
	u32 size_hdr = sizeof(struct acpi_rhct_node_header);
	struct acpi_rhct_node_header *node, *end;
	struct acpi_rhct_hart_info *hart_info;
	struct acpi_table_rhct *rhct;

	if (acpi_disabled)
		return;

	if (table) {
		rhct = (struct acpi_table_rhct *)table;
	} else {
		rhct = acpi_get_rhct();
		if (!rhct)
			return;
	}

	if (cbom_size)
		*cbom_size = 0;

	if (cboz_size)
		*cboz_size = 0;

	if (cbop_size)
		*cbop_size = 0;

	end = ACPI_ADD_PTR(struct acpi_rhct_node_header, rhct, rhct->header.length);
	for (node = ACPI_ADD_PTR(struct acpi_rhct_node_header, rhct, rhct->node_offset);
	     node < end;
	     node = ACPI_ADD_PTR(struct acpi_rhct_node_header, node, node->length)) {
		if (node->type == ACPI_RHCT_NODE_TYPE_HART_INFO) {
			hart_info = ACPI_ADD_PTR(struct acpi_rhct_hart_info, node, size_hdr);
			acpi_parse_hart_info_cmo_node(rhct, hart_info, cbom_size,
						      cboz_size, cbop_size);
		}
	}
}