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 .dyn_proc_status = 2, 40 .decr_val = 0x00ff0000, 41 .fpregs_in_use = 1, 42 .end_of_quantum = 0xfffffffffffffffful, 43 .slb_count = 64, 44 .vmxregs_in_use = 0, 45 .page_ins = 0, 46 }, 47 }; 48 49 static struct lppaca *extra_lppacas; 50 static long __initdata lppaca_size; 51 52 static void allocate_lppacas(int nr_cpus, unsigned long limit) 53 { 54 if (nr_cpus <= NR_LPPACAS) 55 return; 56 57 lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * 58 (nr_cpus - NR_LPPACAS)); 59 extra_lppacas = __va(memblock_alloc_base(lppaca_size, 60 PAGE_SIZE, limit)); 61 } 62 63 static struct lppaca *new_lppaca(int cpu) 64 { 65 struct lppaca *lp; 66 67 if (cpu < NR_LPPACAS) 68 return &lppaca[cpu]; 69 70 lp = extra_lppacas + (cpu - NR_LPPACAS); 71 *lp = lppaca[0]; 72 73 return lp; 74 } 75 76 static void free_lppacas(void) 77 { 78 long new_size = 0, nr; 79 80 if (!lppaca_size) 81 return; 82 nr = num_possible_cpus() - NR_LPPACAS; 83 if (nr > 0) 84 new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); 85 if (new_size >= lppaca_size) 86 return; 87 88 memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); 89 lppaca_size = new_size; 90 } 91 92 #else 93 94 static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } 95 static inline void free_lppacas(void) { } 96 97 #endif /* CONFIG_PPC_BOOK3S */ 98 99 #ifdef CONFIG_PPC_STD_MMU_64 100 101 /* 102 * 3 persistent SLBs are registered here. The buffer will be zero 103 * initially, hence will all be invaild until we actually write them. 104 */ 105 struct slb_shadow slb_shadow[] __cacheline_aligned = { 106 [0 ... (NR_CPUS-1)] = { 107 .persistent = SLB_NUM_BOLTED, 108 .buffer_length = sizeof(struct slb_shadow), 109 }, 110 }; 111 112 #endif /* CONFIG_PPC_STD_MMU_64 */ 113 114 /* The Paca is an array with one entry per processor. Each contains an 115 * lppaca, which contains the information shared between the 116 * hypervisor and Linux. 117 * On systems with hardware multi-threading, there are two threads 118 * per processor. The Paca array must contain an entry for each thread. 119 * The VPD Areas will give a max logical processors = 2 * max physical 120 * processors. The processor VPD array needs one entry per physical 121 * processor (not thread). 122 */ 123 struct paca_struct *paca; 124 EXPORT_SYMBOL(paca); 125 126 struct paca_struct boot_paca; 127 128 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 129 { 130 /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB 131 * of the TOC can be addressed using a single machine instruction. 132 */ 133 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; 134 135 #ifdef CONFIG_PPC_BOOK3S 136 new_paca->lppaca_ptr = new_lppaca(cpu); 137 #else 138 new_paca->kernel_pgd = swapper_pg_dir; 139 #endif 140 new_paca->lock_token = 0x8000; 141 new_paca->paca_index = cpu; 142 new_paca->kernel_toc = kernel_toc; 143 new_paca->kernelbase = (unsigned long) _stext; 144 new_paca->kernel_msr = MSR_KERNEL; 145 new_paca->hw_cpu_id = 0xffff; 146 new_paca->kexec_state = KEXEC_STATE_NONE; 147 new_paca->__current = &init_task; 148 #ifdef CONFIG_PPC_STD_MMU_64 149 new_paca->slb_shadow_ptr = &slb_shadow[cpu]; 150 #endif /* CONFIG_PPC_STD_MMU_64 */ 151 } 152 153 /* Put the paca pointer into r13 and SPRG_PACA */ 154 void setup_paca(struct paca_struct *new_paca) 155 { 156 /* Setup r13 */ 157 local_paca = new_paca; 158 159 #ifdef CONFIG_PPC_BOOK3E 160 /* On Book3E, initialize the TLB miss exception frames */ 161 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); 162 #else 163 /* In HV mode, we setup both HPACA and PACA to avoid problems 164 * if we do a GET_PACA() before the feature fixups have been 165 * applied 166 */ 167 if (cpu_has_feature(CPU_FTR_HVMODE)) 168 mtspr(SPRN_SPRG_HPACA, local_paca); 169 #endif 170 mtspr(SPRN_SPRG_PACA, local_paca); 171 172 } 173 174 static int __initdata paca_size; 175 176 void __init allocate_pacas(void) 177 { 178 int cpu, limit; 179 180 /* 181 * We can't take SLB misses on the paca, and we want to access them 182 * in real mode, so allocate them within the RMA and also within 183 * the first segment. 184 */ 185 limit = min(0x10000000ULL, ppc64_rma_size); 186 187 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 188 189 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); 190 memset(paca, 0, paca_size); 191 192 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 193 paca_size, nr_cpu_ids, paca); 194 195 allocate_lppacas(nr_cpu_ids, limit); 196 197 /* Can't use for_each_*_cpu, as they aren't functional yet */ 198 for (cpu = 0; cpu < nr_cpu_ids; cpu++) 199 initialise_paca(&paca[cpu], cpu); 200 } 201 202 void __init free_unused_pacas(void) 203 { 204 int new_size; 205 206 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); 207 208 if (new_size >= paca_size) 209 return; 210 211 memblock_free(__pa(paca) + new_size, paca_size - new_size); 212 213 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 214 paca_size - new_size); 215 216 paca_size = new_size; 217 218 free_lppacas(); 219 } 220