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