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 14 #include <asm/lppaca.h> 15 #include <asm/paca.h> 16 #include <asm/sections.h> 17 #include <asm/pgtable.h> 18 #include <asm/kexec.h> 19 20 /* This symbol is provided by the linker - let it fill in the paca 21 * field correctly */ 22 extern unsigned long __toc_start; 23 24 #ifdef CONFIG_PPC_BOOK3S 25 26 /* 27 * The structure which the hypervisor knows about - this structure 28 * should not cross a page boundary. The vpa_init/register_vpa call 29 * is now known to fail if the lppaca structure crosses a page 30 * boundary. The lppaca is also used on POWER5 pSeries boxes. 31 * The lppaca is 640 bytes long, and cannot readily 32 * change since the hypervisor knows its layout, so a 1kB alignment 33 * will suffice to ensure that it doesn't cross a page boundary. 34 */ 35 struct lppaca lppaca[] = { 36 [0 ... (NR_LPPACAS-1)] = { 37 .desc = cpu_to_be32(0xd397d781), /* "LpPa" */ 38 .size = cpu_to_be16(sizeof(struct lppaca)), 39 .fpregs_in_use = 1, 40 .slb_count = cpu_to_be16(64), 41 .vmxregs_in_use = 0, 42 .page_ins = 0, 43 }, 44 }; 45 46 static struct lppaca *extra_lppacas; 47 static long __initdata lppaca_size; 48 49 static void __init allocate_lppacas(int nr_cpus, unsigned long limit) 50 { 51 if (nr_cpus <= NR_LPPACAS) 52 return; 53 54 lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * 55 (nr_cpus - NR_LPPACAS)); 56 extra_lppacas = __va(memblock_alloc_base(lppaca_size, 57 PAGE_SIZE, limit)); 58 } 59 60 static struct lppaca * __init new_lppaca(int cpu) 61 { 62 struct lppaca *lp; 63 64 if (cpu < NR_LPPACAS) 65 return &lppaca[cpu]; 66 67 lp = extra_lppacas + (cpu - NR_LPPACAS); 68 *lp = lppaca[0]; 69 70 return lp; 71 } 72 73 static void __init free_lppacas(void) 74 { 75 long new_size = 0, nr; 76 77 if (!lppaca_size) 78 return; 79 nr = num_possible_cpus() - NR_LPPACAS; 80 if (nr > 0) 81 new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); 82 if (new_size >= lppaca_size) 83 return; 84 85 memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); 86 lppaca_size = new_size; 87 } 88 89 #else 90 91 static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } 92 static inline void free_lppacas(void) { } 93 94 #endif /* CONFIG_PPC_BOOK3S */ 95 96 #ifdef CONFIG_PPC_STD_MMU_64 97 98 /* 99 * 3 persistent SLBs are registered here. The buffer will be zero 100 * initially, hence will all be invaild until we actually write them. 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 s->persistent = cpu_to_be32(SLB_NUM_BOLTED); 116 s->buffer_length = cpu_to_be32(sizeof(*s)); 117 118 return s; 119 } 120 121 #else /* CONFIG_PPC_STD_MMU_64 */ 122 123 static void __init allocate_slb_shadows(int nr_cpus, int limit) { } 124 125 #endif /* CONFIG_PPC_STD_MMU_64 */ 126 127 /* The Paca is an array with one entry per processor. Each contains an 128 * lppaca, which contains the information shared between the 129 * hypervisor and Linux. 130 * On systems with hardware multi-threading, there are two threads 131 * per processor. The Paca array must contain an entry for each thread. 132 * The VPD Areas will give a max logical processors = 2 * max physical 133 * processors. The processor VPD array needs one entry per physical 134 * processor (not thread). 135 */ 136 struct paca_struct *paca; 137 EXPORT_SYMBOL(paca); 138 139 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 140 { 141 /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB 142 * of the TOC can be addressed using a single machine instruction. 143 */ 144 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; 145 146 #ifdef CONFIG_PPC_BOOK3S 147 new_paca->lppaca_ptr = new_lppaca(cpu); 148 #else 149 new_paca->kernel_pgd = swapper_pg_dir; 150 #endif 151 new_paca->lock_token = 0x8000; 152 new_paca->paca_index = cpu; 153 new_paca->kernel_toc = kernel_toc; 154 new_paca->kernelbase = (unsigned long) _stext; 155 new_paca->kernel_msr = MSR_KERNEL; 156 new_paca->hw_cpu_id = 0xffff; 157 new_paca->kexec_state = KEXEC_STATE_NONE; 158 new_paca->__current = &init_task; 159 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL; 160 #ifdef CONFIG_PPC_STD_MMU_64 161 new_paca->slb_shadow_ptr = init_slb_shadow(cpu); 162 #endif /* CONFIG_PPC_STD_MMU_64 */ 163 164 #ifdef CONFIG_PPC_BOOK3E 165 /* For now -- if we have threads this will be adjusted later */ 166 new_paca->tcd_ptr = &new_paca->tcd; 167 #endif 168 } 169 170 /* Put the paca pointer into r13 and SPRG_PACA */ 171 void setup_paca(struct paca_struct *new_paca) 172 { 173 /* Setup r13 */ 174 local_paca = new_paca; 175 176 #ifdef CONFIG_PPC_BOOK3E 177 /* On Book3E, initialize the TLB miss exception frames */ 178 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); 179 #else 180 /* In HV mode, we setup both HPACA and PACA to avoid problems 181 * if we do a GET_PACA() before the feature fixups have been 182 * applied 183 */ 184 if (cpu_has_feature(CPU_FTR_HVMODE)) 185 mtspr(SPRN_SPRG_HPACA, local_paca); 186 #endif 187 mtspr(SPRN_SPRG_PACA, local_paca); 188 189 } 190 191 static int __initdata paca_size; 192 193 void __init allocate_pacas(void) 194 { 195 int cpu, limit; 196 197 /* 198 * We can't take SLB misses on the paca, and we want to access them 199 * in real mode, so allocate them within the RMA and also within 200 * the first segment. 201 */ 202 limit = min(0x10000000ULL, ppc64_rma_size); 203 204 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 205 206 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); 207 memset(paca, 0, paca_size); 208 209 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 210 paca_size, nr_cpu_ids, paca); 211 212 allocate_lppacas(nr_cpu_ids, limit); 213 214 allocate_slb_shadows(nr_cpu_ids, limit); 215 216 /* Can't use for_each_*_cpu, as they aren't functional yet */ 217 for (cpu = 0; cpu < nr_cpu_ids; cpu++) 218 initialise_paca(&paca[cpu], cpu); 219 } 220 221 void __init free_unused_pacas(void) 222 { 223 int new_size; 224 225 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 226 227 if (new_size >= paca_size) 228 return; 229 230 memblock_free(__pa(paca) + new_size, paca_size - new_size); 231 232 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 233 paca_size - new_size); 234 235 paca_size = new_size; 236 237 free_lppacas(); 238 } 239