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 = 0xd397d781, /* "LpPa" */ 38 .size = sizeof(struct lppaca), 39 .fpregs_in_use = 1, 40 .slb_count = 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 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 *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 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 struct slb_shadow slb_shadow[] __cacheline_aligned = { 103 [0 ... (NR_CPUS-1)] = { 104 .persistent = SLB_NUM_BOLTED, 105 .buffer_length = sizeof(struct slb_shadow), 106 }, 107 }; 108 109 #endif /* CONFIG_PPC_STD_MMU_64 */ 110 111 /* The Paca is an array with one entry per processor. Each contains an 112 * lppaca, which contains the information shared between the 113 * hypervisor and Linux. 114 * On systems with hardware multi-threading, there are two threads 115 * per processor. The Paca array must contain an entry for each thread. 116 * The VPD Areas will give a max logical processors = 2 * max physical 117 * processors. The processor VPD array needs one entry per physical 118 * processor (not thread). 119 */ 120 struct paca_struct *paca; 121 EXPORT_SYMBOL(paca); 122 123 struct paca_struct boot_paca; 124 125 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 126 { 127 /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB 128 * of the TOC can be addressed using a single machine instruction. 129 */ 130 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; 131 132 #ifdef CONFIG_PPC_BOOK3S 133 new_paca->lppaca_ptr = new_lppaca(cpu); 134 #else 135 new_paca->kernel_pgd = swapper_pg_dir; 136 #endif 137 new_paca->lock_token = 0x8000; 138 new_paca->paca_index = cpu; 139 new_paca->kernel_toc = kernel_toc; 140 new_paca->kernelbase = (unsigned long) _stext; 141 new_paca->kernel_msr = MSR_KERNEL; 142 new_paca->hw_cpu_id = 0xffff; 143 new_paca->kexec_state = KEXEC_STATE_NONE; 144 new_paca->__current = &init_task; 145 new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL; 146 #ifdef CONFIG_PPC_STD_MMU_64 147 new_paca->slb_shadow_ptr = &slb_shadow[cpu]; 148 #endif /* CONFIG_PPC_STD_MMU_64 */ 149 } 150 151 /* Put the paca pointer into r13 and SPRG_PACA */ 152 void setup_paca(struct paca_struct *new_paca) 153 { 154 /* Setup r13 */ 155 local_paca = new_paca; 156 157 #ifdef CONFIG_PPC_BOOK3E 158 /* On Book3E, initialize the TLB miss exception frames */ 159 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); 160 #else 161 /* In HV mode, we setup both HPACA and PACA to avoid problems 162 * if we do a GET_PACA() before the feature fixups have been 163 * applied 164 */ 165 if (cpu_has_feature(CPU_FTR_HVMODE)) 166 mtspr(SPRN_SPRG_HPACA, local_paca); 167 #endif 168 mtspr(SPRN_SPRG_PACA, local_paca); 169 170 } 171 172 static int __initdata paca_size; 173 174 void __init allocate_pacas(void) 175 { 176 int cpu, limit; 177 178 /* 179 * We can't take SLB misses on the paca, and we want to access them 180 * in real mode, so allocate them within the RMA and also within 181 * the first segment. 182 */ 183 limit = min(0x10000000ULL, ppc64_rma_size); 184 185 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 186 187 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); 188 memset(paca, 0, paca_size); 189 190 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 191 paca_size, nr_cpu_ids, paca); 192 193 allocate_lppacas(nr_cpu_ids, limit); 194 195 /* Can't use for_each_*_cpu, as they aren't functional yet */ 196 for (cpu = 0; cpu < nr_cpu_ids; cpu++) 197 initialise_paca(&paca[cpu], cpu); 198 } 199 200 void __init free_unused_pacas(void) 201 { 202 int new_size; 203 204 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 205 206 if (new_size >= paca_size) 207 return; 208 209 memblock_free(__pa(paca) + new_size, paca_size - new_size); 210 211 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 212 paca_size - new_size); 213 214 paca_size = new_size; 215 216 free_lppacas(); 217 } 218