1 /* 2 * c 2001 PPC 64 Team, IBM Corp 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 */ 9 10 #include <linux/smp.h> 11 #include <linux/export.h> 12 #include <linux/memblock.h> 13 #include <linux/sched/task.h> 14 15 #include <asm/lppaca.h> 16 #include <asm/paca.h> 17 #include <asm/sections.h> 18 #include <asm/pgtable.h> 19 #include <asm/kexec.h> 20 21 #ifdef CONFIG_PPC_BOOK3S 22 23 /* 24 * The structure which the hypervisor knows about - this structure 25 * should not cross a page boundary. The vpa_init/register_vpa call 26 * is now known to fail if the lppaca structure crosses a page 27 * boundary. The lppaca is also used on POWER5 pSeries boxes. 28 * The lppaca is 640 bytes long, and cannot readily 29 * change since the hypervisor knows its layout, so a 1kB alignment 30 * will suffice to ensure that it doesn't cross a page boundary. 31 */ 32 struct lppaca lppaca[] = { 33 [0 ... (NR_LPPACAS-1)] = { 34 .desc = cpu_to_be32(0xd397d781), /* "LpPa" */ 35 .size = cpu_to_be16(sizeof(struct lppaca)), 36 .fpregs_in_use = 1, 37 .slb_count = cpu_to_be16(64), 38 .vmxregs_in_use = 0, 39 .page_ins = 0, 40 }, 41 }; 42 43 static struct lppaca *extra_lppacas; 44 static long __initdata lppaca_size; 45 46 static void __init allocate_lppacas(int nr_cpus, unsigned long limit) 47 { 48 if (nr_cpus <= NR_LPPACAS) 49 return; 50 51 lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * 52 (nr_cpus - NR_LPPACAS)); 53 extra_lppacas = __va(memblock_alloc_base(lppaca_size, 54 PAGE_SIZE, limit)); 55 } 56 57 static struct lppaca * __init new_lppaca(int cpu) 58 { 59 struct lppaca *lp; 60 61 if (cpu < NR_LPPACAS) 62 return &lppaca[cpu]; 63 64 lp = extra_lppacas + (cpu - NR_LPPACAS); 65 *lp = lppaca[0]; 66 67 return lp; 68 } 69 70 static void __init free_lppacas(void) 71 { 72 long new_size = 0, nr; 73 74 if (!lppaca_size) 75 return; 76 nr = num_possible_cpus() - NR_LPPACAS; 77 if (nr > 0) 78 new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); 79 if (new_size >= lppaca_size) 80 return; 81 82 memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); 83 lppaca_size = new_size; 84 } 85 86 #else 87 88 static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } 89 static inline void free_lppacas(void) { } 90 91 #endif /* CONFIG_PPC_BOOK3S */ 92 93 #ifdef CONFIG_PPC_STD_MMU_64 94 95 /* 96 * 3 persistent SLBs are registered here. The buffer will be zero 97 * initially, hence will all be invaild until we actually write them. 98 * 99 * If you make the number of persistent SLB entries dynamic, please also 100 * update PR KVM to flush and restore them accordingly. 101 */ 102 static struct slb_shadow *slb_shadow; 103 104 static void __init allocate_slb_shadows(int nr_cpus, int limit) 105 { 106 int size = PAGE_ALIGN(sizeof(struct slb_shadow) * nr_cpus); 107 slb_shadow = __va(memblock_alloc_base(size, PAGE_SIZE, limit)); 108 memset(slb_shadow, 0, size); 109 } 110 111 static struct slb_shadow * __init init_slb_shadow(int cpu) 112 { 113 struct slb_shadow *s = &slb_shadow[cpu]; 114 115 /* 116 * When we come through here to initialise boot_paca, the slb_shadow 117 * buffers are not allocated yet. That's OK, we'll get one later in 118 * boot, but make sure we don't corrupt memory at 0. 119 */ 120 if (!slb_shadow) 121 return NULL; 122 123 s->persistent = cpu_to_be32(SLB_NUM_BOLTED); 124 s->buffer_length = cpu_to_be32(sizeof(*s)); 125 126 return s; 127 } 128 129 #else /* CONFIG_PPC_STD_MMU_64 */ 130 131 static void __init allocate_slb_shadows(int nr_cpus, int limit) { } 132 133 #endif /* CONFIG_PPC_STD_MMU_64 */ 134 135 /* The Paca is an array with one entry per processor. Each contains an 136 * lppaca, which contains the information shared between the 137 * hypervisor and Linux. 138 * On systems with hardware multi-threading, there are two threads 139 * per processor. The Paca array must contain an entry for each thread. 140 * The VPD Areas will give a max logical processors = 2 * max physical 141 * processors. The processor VPD array needs one entry per physical 142 * processor (not thread). 143 */ 144 struct paca_struct *paca; 145 EXPORT_SYMBOL(paca); 146 147 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 148 { 149 #ifdef CONFIG_PPC_BOOK3S 150 new_paca->lppaca_ptr = new_lppaca(cpu); 151 #else 152 new_paca->kernel_pgd = swapper_pg_dir; 153 #endif 154 new_paca->lock_token = 0x8000; 155 new_paca->paca_index = cpu; 156 new_paca->kernel_toc = kernel_toc_addr(); 157 new_paca->kernelbase = (unsigned long) _stext; 158 /* Only set MSR:IR/DR when MMU is initialized */ 159 new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR); 160 new_paca->hw_cpu_id = 0xffff; 161 new_paca->kexec_state = KEXEC_STATE_NONE; 162 new_paca->__current = &init_task; 163 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL; 164 #ifdef CONFIG_PPC_STD_MMU_64 165 new_paca->slb_shadow_ptr = init_slb_shadow(cpu); 166 #endif /* CONFIG_PPC_STD_MMU_64 */ 167 168 #ifdef CONFIG_PPC_BOOK3E 169 /* For now -- if we have threads this will be adjusted later */ 170 new_paca->tcd_ptr = &new_paca->tcd; 171 #endif 172 } 173 174 /* Put the paca pointer into r13 and SPRG_PACA */ 175 void setup_paca(struct paca_struct *new_paca) 176 { 177 /* Setup r13 */ 178 local_paca = new_paca; 179 180 #ifdef CONFIG_PPC_BOOK3E 181 /* On Book3E, initialize the TLB miss exception frames */ 182 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); 183 #else 184 /* In HV mode, we setup both HPACA and PACA to avoid problems 185 * if we do a GET_PACA() before the feature fixups have been 186 * applied 187 */ 188 if (early_cpu_has_feature(CPU_FTR_HVMODE)) 189 mtspr(SPRN_SPRG_HPACA, local_paca); 190 #endif 191 mtspr(SPRN_SPRG_PACA, local_paca); 192 193 } 194 195 static int __initdata paca_size; 196 197 void __init allocate_pacas(void) 198 { 199 u64 limit; 200 int cpu; 201 202 limit = ppc64_rma_size; 203 204 #ifdef CONFIG_PPC_BOOK3S_64 205 /* 206 * We can't take SLB misses on the paca, and we want to access them 207 * in real mode, so allocate them within the RMA and also within 208 * the first segment. 209 */ 210 limit = min(0x10000000ULL, limit); 211 #endif 212 213 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 214 215 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); 216 memset(paca, 0, paca_size); 217 218 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 219 paca_size, nr_cpu_ids, paca); 220 221 allocate_lppacas(nr_cpu_ids, limit); 222 223 allocate_slb_shadows(nr_cpu_ids, limit); 224 225 /* Can't use for_each_*_cpu, as they aren't functional yet */ 226 for (cpu = 0; cpu < nr_cpu_ids; cpu++) 227 initialise_paca(&paca[cpu], cpu); 228 } 229 230 void __init free_unused_pacas(void) 231 { 232 int new_size; 233 234 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 235 236 if (new_size >= paca_size) 237 return; 238 239 memblock_free(__pa(paca) + new_size, paca_size - new_size); 240 241 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 242 paca_size - new_size); 243 244 paca_size = new_size; 245 246 free_lppacas(); 247 } 248