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/threads.h> 11 #include <linux/module.h> 12 #include <linux/memblock.h> 13 14 #include <asm/firmware.h> 15 #include <asm/lppaca.h> 16 #include <asm/paca.h> 17 #include <asm/sections.h> 18 #include <asm/pgtable.h> 19 #include <asm/iseries/lpar_map.h> 20 #include <asm/iseries/hv_types.h> 21 #include <asm/kexec.h> 22 23 /* This symbol is provided by the linker - let it fill in the paca 24 * field correctly */ 25 extern unsigned long __toc_start; 26 27 #ifdef CONFIG_PPC_BOOK3S 28 29 /* 30 * We only have to have statically allocated lppaca structs on 31 * legacy iSeries, which supports at most 64 cpus. 32 */ 33 #ifdef CONFIG_PPC_ISERIES 34 #if NR_CPUS < 64 35 #define NR_LPPACAS NR_CPUS 36 #else 37 #define NR_LPPACAS 64 38 #endif 39 #else /* not iSeries */ 40 #define NR_LPPACAS 1 41 #endif 42 43 /* 44 * The structure which the hypervisor knows about - this structure 45 * should not cross a page boundary. The vpa_init/register_vpa call 46 * is now known to fail if the lppaca structure crosses a page 47 * boundary. The lppaca is also used on legacy iSeries and POWER5 48 * pSeries boxes. The lppaca is 640 bytes long, and cannot readily 49 * change since the hypervisor knows its layout, so a 1kB alignment 50 * will suffice to ensure that it doesn't cross a page boundary. 51 */ 52 struct lppaca lppaca[] = { 53 [0 ... (NR_LPPACAS-1)] = { 54 .desc = 0xd397d781, /* "LpPa" */ 55 .size = sizeof(struct lppaca), 56 .dyn_proc_status = 2, 57 .decr_val = 0x00ff0000, 58 .fpregs_in_use = 1, 59 .end_of_quantum = 0xfffffffffffffffful, 60 .slb_count = 64, 61 .vmxregs_in_use = 0, 62 .page_ins = 0, 63 }, 64 }; 65 66 static struct lppaca *extra_lppacas; 67 static long __initdata lppaca_size; 68 69 static void allocate_lppacas(int nr_cpus, unsigned long limit) 70 { 71 if (nr_cpus <= NR_LPPACAS) 72 return; 73 74 lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * 75 (nr_cpus - NR_LPPACAS)); 76 extra_lppacas = __va(memblock_alloc_base(lppaca_size, 77 PAGE_SIZE, limit)); 78 } 79 80 static struct lppaca *new_lppaca(int cpu) 81 { 82 struct lppaca *lp; 83 84 if (cpu < NR_LPPACAS) 85 return &lppaca[cpu]; 86 87 lp = extra_lppacas + (cpu - NR_LPPACAS); 88 *lp = lppaca[0]; 89 90 return lp; 91 } 92 93 static void free_lppacas(void) 94 { 95 long new_size = 0, nr; 96 97 if (!lppaca_size) 98 return; 99 nr = num_possible_cpus() - NR_LPPACAS; 100 if (nr > 0) 101 new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); 102 if (new_size >= lppaca_size) 103 return; 104 105 memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); 106 lppaca_size = new_size; 107 } 108 109 #else 110 111 static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } 112 static inline void free_lppacas(void) { } 113 114 #endif /* CONFIG_PPC_BOOK3S */ 115 116 #ifdef CONFIG_PPC_STD_MMU_64 117 118 /* 119 * 3 persistent SLBs are registered here. The buffer will be zero 120 * initially, hence will all be invaild until we actually write them. 121 */ 122 struct slb_shadow slb_shadow[] __cacheline_aligned = { 123 [0 ... (NR_CPUS-1)] = { 124 .persistent = SLB_NUM_BOLTED, 125 .buffer_length = sizeof(struct slb_shadow), 126 }, 127 }; 128 129 #endif /* CONFIG_PPC_STD_MMU_64 */ 130 131 /* The Paca is an array with one entry per processor. Each contains an 132 * lppaca, which contains the information shared between the 133 * hypervisor and Linux. 134 * On systems with hardware multi-threading, there are two threads 135 * per processor. The Paca array must contain an entry for each thread. 136 * The VPD Areas will give a max logical processors = 2 * max physical 137 * processors. The processor VPD array needs one entry per physical 138 * processor (not thread). 139 */ 140 struct paca_struct *paca; 141 EXPORT_SYMBOL(paca); 142 143 struct paca_struct boot_paca; 144 145 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 146 { 147 /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB 148 * of the TOC can be addressed using a single machine instruction. 149 */ 150 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; 151 152 #ifdef CONFIG_PPC_BOOK3S 153 new_paca->lppaca_ptr = new_lppaca(cpu); 154 #else 155 new_paca->kernel_pgd = swapper_pg_dir; 156 #endif 157 new_paca->lock_token = 0x8000; 158 new_paca->paca_index = cpu; 159 new_paca->kernel_toc = kernel_toc; 160 new_paca->kernelbase = (unsigned long) _stext; 161 new_paca->kernel_msr = MSR_KERNEL; 162 new_paca->hw_cpu_id = 0xffff; 163 new_paca->kexec_state = KEXEC_STATE_NONE; 164 new_paca->__current = &init_task; 165 #ifdef CONFIG_PPC_STD_MMU_64 166 new_paca->slb_shadow_ptr = &slb_shadow[cpu]; 167 #endif /* CONFIG_PPC_STD_MMU_64 */ 168 } 169 170 /* Put the paca pointer into r13 and SPRG_PACA */ 171 void setup_paca(struct paca_struct *new_paca) 172 { 173 local_paca = new_paca; 174 mtspr(SPRN_SPRG_PACA, local_paca); 175 #ifdef CONFIG_PPC_BOOK3E 176 mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); 177 #endif 178 } 179 180 static int __initdata paca_size; 181 182 void __init allocate_pacas(void) 183 { 184 int nr_cpus, cpu, limit; 185 186 /* 187 * We can't take SLB misses on the paca, and we want to access them 188 * in real mode, so allocate them within the RMA and also within 189 * the first segment. On iSeries they must be within the area mapped 190 * by the HV, which is HvPagesToMap * HVPAGESIZE bytes. 191 */ 192 limit = min(0x10000000ULL, ppc64_rma_size); 193 if (firmware_has_feature(FW_FEATURE_ISERIES)) 194 limit = min(limit, HvPagesToMap * HVPAGESIZE); 195 196 nr_cpus = NR_CPUS; 197 /* On iSeries we know we can never have more than 64 cpus */ 198 if (firmware_has_feature(FW_FEATURE_ISERIES)) 199 nr_cpus = min(64, nr_cpus); 200 201 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpus); 202 203 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); 204 memset(paca, 0, paca_size); 205 206 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 207 paca_size, nr_cpus, paca); 208 209 allocate_lppacas(nr_cpus, limit); 210 211 /* Can't use for_each_*_cpu, as they aren't functional yet */ 212 for (cpu = 0; cpu < nr_cpus; cpu++) 213 initialise_paca(&paca[cpu], cpu); 214 } 215 216 void __init free_unused_pacas(void) 217 { 218 int new_size; 219 220 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus()); 221 222 if (new_size >= paca_size) 223 return; 224 225 memblock_free(__pa(paca) + new_size, paca_size - new_size); 226 227 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 228 paca_size - new_size); 229 230 paca_size = new_size; 231 232 free_lppacas(); 233 } 234