1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2021 Sifive. 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/module.h> 8 #include <linux/string.h> 9 #include <linux/bug.h> 10 #include <asm/patch.h> 11 #include <asm/alternative.h> 12 #include <asm/vendorid_list.h> 13 #include <asm/errata_list.h> 14 15 struct errata_info_t { 16 char name[ERRATA_STRING_LENGTH_MAX]; 17 bool (*check_func)(unsigned long arch_id, unsigned long impid); 18 }; 19 20 static bool errata_cip_453_check_func(unsigned long arch_id, unsigned long impid) 21 { 22 /* 23 * Affected cores: 24 * Architecture ID: 0x8000000000000007 25 * Implement ID: 0x20181004 <= impid <= 0x20191105 26 */ 27 if (arch_id != 0x8000000000000007 || 28 (impid < 0x20181004 || impid > 0x20191105)) 29 return false; 30 return true; 31 } 32 33 static bool errata_cip_1200_check_func(unsigned long arch_id, unsigned long impid) 34 { 35 /* 36 * Affected cores: 37 * Architecture ID: 0x8000000000000007 or 0x1 38 * Implement ID: mimpid[23:0] <= 0x200630 and mimpid != 0x01200626 39 */ 40 if (arch_id != 0x8000000000000007 && arch_id != 0x1) 41 return false; 42 if ((impid & 0xffffff) > 0x200630 || impid == 0x1200626) 43 return false; 44 return true; 45 } 46 47 static struct errata_info_t errata_list[ERRATA_SIFIVE_NUMBER] = { 48 { 49 .name = "cip-453", 50 .check_func = errata_cip_453_check_func 51 }, 52 { 53 .name = "cip-1200", 54 .check_func = errata_cip_1200_check_func 55 }, 56 }; 57 58 static u32 __init_or_module sifive_errata_probe(unsigned long archid, 59 unsigned long impid) 60 { 61 int idx; 62 u32 cpu_req_errata = 0; 63 64 for (idx = 0; idx < ERRATA_SIFIVE_NUMBER; idx++) 65 if (errata_list[idx].check_func(archid, impid)) 66 cpu_req_errata |= (1U << idx); 67 68 return cpu_req_errata; 69 } 70 71 static void __init_or_module warn_miss_errata(u32 miss_errata) 72 { 73 int i; 74 75 pr_warn("----------------------------------------------------------------\n"); 76 pr_warn("WARNING: Missing the following errata may cause potential issues\n"); 77 for (i = 0; i < ERRATA_SIFIVE_NUMBER; i++) 78 if (miss_errata & 0x1 << i) 79 pr_warn("\tSiFive Errata[%d]:%s\n", i, errata_list[i].name); 80 pr_warn("Please enable the corresponding Kconfig to apply them\n"); 81 pr_warn("----------------------------------------------------------------\n"); 82 } 83 84 void __init_or_module sifive_errata_patch_func(struct alt_entry *begin, 85 struct alt_entry *end, 86 unsigned long archid, 87 unsigned long impid, 88 unsigned int stage) 89 { 90 struct alt_entry *alt; 91 u32 cpu_req_errata; 92 u32 cpu_apply_errata = 0; 93 u32 tmp; 94 95 if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) 96 return; 97 98 cpu_req_errata = sifive_errata_probe(archid, impid); 99 100 for (alt = begin; alt < end; alt++) { 101 if (alt->vendor_id != SIFIVE_VENDOR_ID) 102 continue; 103 if (alt->errata_id >= ERRATA_SIFIVE_NUMBER) { 104 WARN(1, "This errata id:%d is not in kernel errata list", alt->errata_id); 105 continue; 106 } 107 108 tmp = (1U << alt->errata_id); 109 if (cpu_req_errata & tmp) { 110 patch_text_nosync(alt->old_ptr, alt->alt_ptr, alt->alt_len); 111 cpu_apply_errata |= tmp; 112 } 113 } 114 if (cpu_apply_errata != cpu_req_errata) 115 warn_miss_errata(cpu_req_errata - cpu_apply_errata); 116 } 117