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