1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Regents of the University of California 4 */ 5 6 #include <linux/init.h> 7 #include <linux/seq_file.h> 8 #include <linux/of.h> 9 #include <asm/hwcap.h> 10 #include <asm/smp.h> 11 #include <asm/pgtable.h> 12 13 /* 14 * Returns the hart ID of the given device tree node, or -ENODEV if the node 15 * isn't an enabled and valid RISC-V hart node. 16 */ 17 int riscv_of_processor_hartid(struct device_node *node) 18 { 19 const char *isa; 20 u32 hart; 21 22 if (!of_device_is_compatible(node, "riscv")) { 23 pr_warn("Found incompatible CPU\n"); 24 return -ENODEV; 25 } 26 27 hart = of_get_cpu_hwid(node, 0); 28 if (hart == ~0U) { 29 pr_warn("Found CPU without hart ID\n"); 30 return -ENODEV; 31 } 32 33 if (!of_device_is_available(node)) { 34 pr_info("CPU with hartid=%d is not available\n", hart); 35 return -ENODEV; 36 } 37 38 if (of_property_read_string(node, "riscv,isa", &isa)) { 39 pr_warn("CPU with hartid=%d has no \"riscv,isa\" property\n", hart); 40 return -ENODEV; 41 } 42 if (isa[0] != 'r' || isa[1] != 'v') { 43 pr_warn("CPU with hartid=%d has an invalid ISA of \"%s\"\n", hart, isa); 44 return -ENODEV; 45 } 46 47 return hart; 48 } 49 50 /* 51 * Find hart ID of the CPU DT node under which given DT node falls. 52 * 53 * To achieve this, we walk up the DT tree until we find an active 54 * RISC-V core (HART) node and extract the cpuid from it. 55 */ 56 int riscv_of_parent_hartid(struct device_node *node) 57 { 58 for (; node; node = node->parent) { 59 if (of_device_is_compatible(node, "riscv")) 60 return riscv_of_processor_hartid(node); 61 } 62 63 return -1; 64 } 65 66 #ifdef CONFIG_PROC_FS 67 #define __RISCV_ISA_EXT_DATA(UPROP, EXTID) \ 68 { \ 69 .uprop = #UPROP, \ 70 .isa_ext_id = EXTID, \ 71 } 72 /* 73 * Here are the ordering rules of extension naming defined by RISC-V 74 * specification : 75 * 1. All extensions should be separated from other multi-letter extensions 76 * by an underscore. 77 * 2. The first letter following the 'Z' conventionally indicates the most 78 * closely related alphabetical extension category, IMAFDQLCBKJTPVH. 79 * If multiple 'Z' extensions are named, they should be ordered first 80 * by category, then alphabetically within a category. 81 * 3. Standard supervisor-level extensions (starts with 'S') should be 82 * listed after standard unprivileged extensions. If multiple 83 * supervisor-level extensions are listed, they should be ordered 84 * alphabetically. 85 * 4. Non-standard extensions (starts with 'X') must be listed after all 86 * standard extensions. They must be separated from other multi-letter 87 * extensions by an underscore. 88 */ 89 static struct riscv_isa_ext_data isa_ext_arr[] = { 90 __RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF), 91 __RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX), 92 }; 93 94 static void print_isa_ext(struct seq_file *f) 95 { 96 struct riscv_isa_ext_data *edata; 97 int i = 0, arr_sz; 98 99 arr_sz = ARRAY_SIZE(isa_ext_arr) - 1; 100 101 /* No extension support available */ 102 if (arr_sz <= 0) 103 return; 104 105 for (i = 0; i <= arr_sz; i++) { 106 edata = &isa_ext_arr[i]; 107 if (!__riscv_isa_extension_available(NULL, edata->isa_ext_id)) 108 continue; 109 seq_printf(f, "_%s", edata->uprop); 110 } 111 } 112 113 /* 114 * These are the only valid base (single letter) ISA extensions as per the spec. 115 * It also specifies the canonical order in which it appears in the spec. 116 * Some of the extension may just be a place holder for now (B, K, P, J). 117 * This should be updated once corresponding extensions are ratified. 118 */ 119 static const char base_riscv_exts[13] = "imafdqcbkjpvh"; 120 121 static void print_isa(struct seq_file *f, const char *isa) 122 { 123 int i; 124 125 seq_puts(f, "isa\t\t: "); 126 /* Print the rv[64/32] part */ 127 seq_write(f, isa, 4); 128 for (i = 0; i < sizeof(base_riscv_exts); i++) { 129 if (__riscv_isa_extension_available(NULL, base_riscv_exts[i] - 'a')) 130 /* Print only enabled the base ISA extensions */ 131 seq_write(f, &base_riscv_exts[i], 1); 132 } 133 print_isa_ext(f); 134 seq_puts(f, "\n"); 135 } 136 137 static void print_mmu(struct seq_file *f) 138 { 139 char sv_type[16]; 140 141 #if defined(CONFIG_32BIT) 142 strncpy(sv_type, "sv32", 5); 143 #elif defined(CONFIG_64BIT) 144 if (pgtable_l5_enabled) 145 strncpy(sv_type, "sv57", 5); 146 else if (pgtable_l4_enabled) 147 strncpy(sv_type, "sv48", 5); 148 else 149 strncpy(sv_type, "sv39", 5); 150 #endif 151 seq_printf(f, "mmu\t\t: %s\n", sv_type); 152 } 153 154 static void *c_start(struct seq_file *m, loff_t *pos) 155 { 156 *pos = cpumask_next(*pos - 1, cpu_online_mask); 157 if ((*pos) < nr_cpu_ids) 158 return (void *)(uintptr_t)(1 + *pos); 159 return NULL; 160 } 161 162 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 163 { 164 (*pos)++; 165 return c_start(m, pos); 166 } 167 168 static void c_stop(struct seq_file *m, void *v) 169 { 170 } 171 172 static int c_show(struct seq_file *m, void *v) 173 { 174 unsigned long cpu_id = (unsigned long)v - 1; 175 struct device_node *node = of_get_cpu_node(cpu_id, NULL); 176 const char *compat, *isa; 177 178 seq_printf(m, "processor\t: %lu\n", cpu_id); 179 seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id)); 180 if (!of_property_read_string(node, "riscv,isa", &isa)) 181 print_isa(m, isa); 182 print_mmu(m); 183 if (!of_property_read_string(node, "compatible", &compat) 184 && strcmp(compat, "riscv")) 185 seq_printf(m, "uarch\t\t: %s\n", compat); 186 seq_puts(m, "\n"); 187 of_node_put(node); 188 189 return 0; 190 } 191 192 const struct seq_operations cpuinfo_op = { 193 .start = c_start, 194 .next = c_next, 195 .stop = c_stop, 196 .show = c_show 197 }; 198 199 #endif /* CONFIG_PROC_FS */ 200