1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 4 */ 5 #include <linux/init.h> 6 #include <linux/sched.h> 7 #include <linux/smp.h> 8 #include <linux/mm.h> 9 #include <linux/hugetlb.h> 10 #include <linux/export.h> 11 12 #include <asm/cpu.h> 13 #include <asm/bootinfo.h> 14 #include <asm/mmu_context.h> 15 #include <asm/pgtable.h> 16 #include <asm/tlb.h> 17 18 void local_flush_tlb_all(void) 19 { 20 invtlb_all(INVTLB_CURRENT_ALL, 0, 0); 21 } 22 EXPORT_SYMBOL(local_flush_tlb_all); 23 24 void local_flush_tlb_user(void) 25 { 26 invtlb_all(INVTLB_CURRENT_GFALSE, 0, 0); 27 } 28 EXPORT_SYMBOL(local_flush_tlb_user); 29 30 void local_flush_tlb_kernel(void) 31 { 32 invtlb_all(INVTLB_CURRENT_GTRUE, 0, 0); 33 } 34 EXPORT_SYMBOL(local_flush_tlb_kernel); 35 36 /* 37 * All entries common to a mm share an asid. To effectively flush 38 * these entries, we just bump the asid. 39 */ 40 void local_flush_tlb_mm(struct mm_struct *mm) 41 { 42 int cpu; 43 44 preempt_disable(); 45 46 cpu = smp_processor_id(); 47 48 if (asid_valid(mm, cpu)) 49 drop_mmu_context(mm, cpu); 50 else 51 cpumask_clear_cpu(cpu, mm_cpumask(mm)); 52 53 preempt_enable(); 54 } 55 56 void local_flush_tlb_range(struct vm_area_struct *vma, unsigned long start, 57 unsigned long end) 58 { 59 struct mm_struct *mm = vma->vm_mm; 60 int cpu = smp_processor_id(); 61 62 if (asid_valid(mm, cpu)) { 63 unsigned long size, flags; 64 65 local_irq_save(flags); 66 start = round_down(start, PAGE_SIZE << 1); 67 end = round_up(end, PAGE_SIZE << 1); 68 size = (end - start) >> (PAGE_SHIFT + 1); 69 if (size <= (current_cpu_data.tlbsizestlbsets ? 70 current_cpu_data.tlbsize / 8 : 71 current_cpu_data.tlbsize / 2)) { 72 int asid = cpu_asid(cpu, mm); 73 74 while (start < end) { 75 invtlb(INVTLB_ADDR_GFALSE_AND_ASID, asid, start); 76 start += (PAGE_SIZE << 1); 77 } 78 } else { 79 drop_mmu_context(mm, cpu); 80 } 81 local_irq_restore(flags); 82 } else { 83 cpumask_clear_cpu(cpu, mm_cpumask(mm)); 84 } 85 } 86 87 void local_flush_tlb_kernel_range(unsigned long start, unsigned long end) 88 { 89 unsigned long size, flags; 90 91 local_irq_save(flags); 92 size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 93 size = (size + 1) >> 1; 94 if (size <= (current_cpu_data.tlbsizestlbsets ? 95 current_cpu_data.tlbsize / 8 : 96 current_cpu_data.tlbsize / 2)) { 97 98 start &= (PAGE_MASK << 1); 99 end += ((PAGE_SIZE << 1) - 1); 100 end &= (PAGE_MASK << 1); 101 102 while (start < end) { 103 invtlb_addr(INVTLB_ADDR_GTRUE_OR_ASID, 0, start); 104 start += (PAGE_SIZE << 1); 105 } 106 } else { 107 local_flush_tlb_kernel(); 108 } 109 local_irq_restore(flags); 110 } 111 112 void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long page) 113 { 114 int cpu = smp_processor_id(); 115 116 if (asid_valid(vma->vm_mm, cpu)) { 117 int newpid; 118 119 newpid = cpu_asid(cpu, vma->vm_mm); 120 page &= (PAGE_MASK << 1); 121 invtlb(INVTLB_ADDR_GFALSE_AND_ASID, newpid, page); 122 } else { 123 cpumask_clear_cpu(cpu, mm_cpumask(vma->vm_mm)); 124 } 125 } 126 127 /* 128 * This one is only used for pages with the global bit set so we don't care 129 * much about the ASID. 130 */ 131 void local_flush_tlb_one(unsigned long page) 132 { 133 page &= (PAGE_MASK << 1); 134 invtlb_addr(INVTLB_ADDR_GTRUE_OR_ASID, 0, page); 135 } 136 137 static void __update_hugetlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) 138 { 139 #ifdef CONFIG_HUGETLB_PAGE 140 int idx; 141 unsigned long lo; 142 unsigned long flags; 143 144 local_irq_save(flags); 145 146 address &= (PAGE_MASK << 1); 147 write_csr_entryhi(address); 148 tlb_probe(); 149 idx = read_csr_tlbidx(); 150 write_csr_pagesize(PS_HUGE_SIZE); 151 lo = pmd_to_entrylo(pte_val(*ptep)); 152 write_csr_entrylo0(lo); 153 write_csr_entrylo1(lo + (HPAGE_SIZE >> 1)); 154 155 if (idx < 0) 156 tlb_write_random(); 157 else 158 tlb_write_indexed(); 159 write_csr_pagesize(PS_DEFAULT_SIZE); 160 161 local_irq_restore(flags); 162 #endif 163 } 164 165 void __update_tlb(struct vm_area_struct *vma, unsigned long address, pte_t *ptep) 166 { 167 int idx; 168 unsigned long flags; 169 170 if (cpu_has_ptw) 171 return; 172 173 /* 174 * Handle debugger faulting in for debugee. 175 */ 176 if (current->active_mm != vma->vm_mm) 177 return; 178 179 if (pte_val(*ptep) & _PAGE_HUGE) { 180 __update_hugetlb(vma, address, ptep); 181 return; 182 } 183 184 local_irq_save(flags); 185 186 if ((unsigned long)ptep & sizeof(pte_t)) 187 ptep--; 188 189 address &= (PAGE_MASK << 1); 190 write_csr_entryhi(address); 191 tlb_probe(); 192 idx = read_csr_tlbidx(); 193 write_csr_pagesize(PS_DEFAULT_SIZE); 194 write_csr_entrylo0(pte_val(*ptep++)); 195 write_csr_entrylo1(pte_val(*ptep)); 196 if (idx < 0) 197 tlb_write_random(); 198 else 199 tlb_write_indexed(); 200 201 local_irq_restore(flags); 202 } 203 204 static void setup_ptwalker(void) 205 { 206 unsigned long pwctl0, pwctl1; 207 unsigned long pgd_i = 0, pgd_w = 0; 208 unsigned long pud_i = 0, pud_w = 0; 209 unsigned long pmd_i = 0, pmd_w = 0; 210 unsigned long pte_i = 0, pte_w = 0; 211 212 pgd_i = PGDIR_SHIFT; 213 pgd_w = PAGE_SHIFT - 3; 214 #if CONFIG_PGTABLE_LEVELS > 3 215 pud_i = PUD_SHIFT; 216 pud_w = PAGE_SHIFT - 3; 217 #endif 218 #if CONFIG_PGTABLE_LEVELS > 2 219 pmd_i = PMD_SHIFT; 220 pmd_w = PAGE_SHIFT - 3; 221 #endif 222 pte_i = PAGE_SHIFT; 223 pte_w = PAGE_SHIFT - 3; 224 225 pwctl0 = pte_i | pte_w << 5 | pmd_i << 10 | pmd_w << 15 | pud_i << 20 | pud_w << 25; 226 pwctl1 = pgd_i | pgd_w << 6; 227 228 if (cpu_has_ptw) 229 pwctl1 |= CSR_PWCTL1_PTW; 230 231 csr_write64(pwctl0, LOONGARCH_CSR_PWCTL0); 232 csr_write64(pwctl1, LOONGARCH_CSR_PWCTL1); 233 csr_write64((long)swapper_pg_dir, LOONGARCH_CSR_PGDH); 234 csr_write64((long)invalid_pg_dir, LOONGARCH_CSR_PGDL); 235 csr_write64((long)smp_processor_id(), LOONGARCH_CSR_TMID); 236 } 237 238 static void output_pgtable_bits_defines(void) 239 { 240 #define pr_define(fmt, ...) \ 241 pr_debug("#define " fmt, ##__VA_ARGS__) 242 243 pr_debug("#include <asm/asm.h>\n"); 244 pr_debug("#include <asm/regdef.h>\n"); 245 pr_debug("\n"); 246 247 pr_define("_PAGE_VALID_SHIFT %d\n", _PAGE_VALID_SHIFT); 248 pr_define("_PAGE_DIRTY_SHIFT %d\n", _PAGE_DIRTY_SHIFT); 249 pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT); 250 pr_define("_PAGE_GLOBAL_SHIFT %d\n", _PAGE_GLOBAL_SHIFT); 251 pr_define("_PAGE_PRESENT_SHIFT %d\n", _PAGE_PRESENT_SHIFT); 252 pr_define("_PAGE_WRITE_SHIFT %d\n", _PAGE_WRITE_SHIFT); 253 pr_define("_PAGE_NO_READ_SHIFT %d\n", _PAGE_NO_READ_SHIFT); 254 pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT); 255 pr_define("PFN_PTE_SHIFT %d\n", PFN_PTE_SHIFT); 256 pr_debug("\n"); 257 } 258 259 #ifdef CONFIG_NUMA 260 unsigned long pcpu_handlers[NR_CPUS]; 261 #endif 262 extern long exception_handlers[VECSIZE * 128 / sizeof(long)]; 263 264 static void setup_tlb_handler(int cpu) 265 { 266 setup_ptwalker(); 267 local_flush_tlb_all(); 268 269 /* The tlb handlers are generated only once */ 270 if (cpu == 0) { 271 memcpy((void *)tlbrentry, handle_tlb_refill, 0x80); 272 local_flush_icache_range(tlbrentry, tlbrentry + 0x80); 273 if (!cpu_has_ptw) { 274 set_handler(EXCCODE_TLBI * VECSIZE, handle_tlb_load, VECSIZE); 275 set_handler(EXCCODE_TLBL * VECSIZE, handle_tlb_load, VECSIZE); 276 set_handler(EXCCODE_TLBS * VECSIZE, handle_tlb_store, VECSIZE); 277 set_handler(EXCCODE_TLBM * VECSIZE, handle_tlb_modify, VECSIZE); 278 } else { 279 set_handler(EXCCODE_TLBI * VECSIZE, handle_tlb_load_ptw, VECSIZE); 280 set_handler(EXCCODE_TLBL * VECSIZE, handle_tlb_load_ptw, VECSIZE); 281 set_handler(EXCCODE_TLBS * VECSIZE, handle_tlb_store_ptw, VECSIZE); 282 set_handler(EXCCODE_TLBM * VECSIZE, handle_tlb_modify_ptw, VECSIZE); 283 } 284 set_handler(EXCCODE_TLBNR * VECSIZE, handle_tlb_protect, VECSIZE); 285 set_handler(EXCCODE_TLBNX * VECSIZE, handle_tlb_protect, VECSIZE); 286 set_handler(EXCCODE_TLBPE * VECSIZE, handle_tlb_protect, VECSIZE); 287 } else { 288 int vec_sz __maybe_unused; 289 void *addr __maybe_unused; 290 struct page *page __maybe_unused; 291 292 /* Avoid lockdep warning */ 293 rcutree_report_cpu_starting(cpu); 294 295 #ifdef CONFIG_NUMA 296 vec_sz = sizeof(exception_handlers); 297 298 if (pcpu_handlers[cpu]) 299 return; 300 301 page = alloc_pages_node(cpu_to_node(cpu), GFP_ATOMIC, get_order(vec_sz)); 302 if (!page) 303 return; 304 305 addr = page_address(page); 306 pcpu_handlers[cpu] = (unsigned long)addr; 307 memcpy((void *)addr, (void *)eentry, vec_sz); 308 local_flush_icache_range((unsigned long)addr, (unsigned long)addr + vec_sz); 309 csr_write64(pcpu_handlers[cpu], LOONGARCH_CSR_EENTRY); 310 csr_write64(pcpu_handlers[cpu], LOONGARCH_CSR_MERRENTRY); 311 csr_write64(pcpu_handlers[cpu] + 80*VECSIZE, LOONGARCH_CSR_TLBRENTRY); 312 #endif 313 } 314 } 315 316 void tlb_init(int cpu) 317 { 318 write_csr_pagesize(PS_DEFAULT_SIZE); 319 write_csr_stlbpgsize(PS_DEFAULT_SIZE); 320 write_csr_tlbrefill_pagesize(PS_DEFAULT_SIZE); 321 322 setup_tlb_handler(cpu); 323 output_pgtable_bits_defines(); 324 } 325