| 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 | #ifdef CONFIG_PPC_BOOK3S |
| 21 | |
| 22 | /* |
| 23 | * The structure which the hypervisor knows about - this structure |
| 24 | * should not cross a page boundary. The vpa_init/register_vpa call |
| 25 | * is now known to fail if the lppaca structure crosses a page |
| 26 | * boundary. The lppaca is also used on POWER5 pSeries boxes. |
| 27 | * The lppaca is 640 bytes long, and cannot readily |
| 28 | * change since the hypervisor knows its layout, so a 1kB alignment |
| 29 | * will suffice to ensure that it doesn't cross a page boundary. |
| 30 | */ |
| 31 | struct lppaca lppaca[] = { |
| 32 | [0 ... (NR_LPPACAS-1)] = { |
| 33 | .desc = cpu_to_be32(0xd397d781), /* "LpPa" */ |
| 34 | .size = cpu_to_be16(sizeof(struct lppaca)), |
| 35 | .fpregs_in_use = 1, |
| 36 | .slb_count = cpu_to_be16(64), |
| 37 | .vmxregs_in_use = 0, |
| 38 | .page_ins = 0, |
| 39 | }, |
| 40 | }; |
| 41 | |
| 42 | static struct lppaca *extra_lppacas; |
| 43 | static long __initdata lppaca_size; |
| 44 | |
| 45 | static void __init allocate_lppacas(int nr_cpus, unsigned long limit) |
| 46 | { |
| 47 | if (nr_cpus <= NR_LPPACAS) |
| 48 | return; |
| 49 | |
| 50 | lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * |
| 51 | (nr_cpus - NR_LPPACAS)); |
| 52 | extra_lppacas = __va(memblock_alloc_base(lppaca_size, |
| 53 | PAGE_SIZE, limit)); |
| 54 | } |
| 55 | |
| 56 | static struct lppaca * __init new_lppaca(int cpu) |
| 57 | { |
| 58 | struct lppaca *lp; |
| 59 | |
| 60 | if (cpu < NR_LPPACAS) |
| 61 | return &lppaca[cpu]; |
| 62 | |
| 63 | lp = extra_lppacas + (cpu - NR_LPPACAS); |
| 64 | *lp = lppaca[0]; |
| 65 | |
| 66 | return lp; |
| 67 | } |
| 68 | |
| 69 | static void __init free_lppacas(void) |
| 70 | { |
| 71 | long new_size = 0, nr; |
| 72 | |
| 73 | if (!lppaca_size) |
| 74 | return; |
| 75 | nr = num_possible_cpus() - NR_LPPACAS; |
| 76 | if (nr > 0) |
| 77 | new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); |
| 78 | if (new_size >= lppaca_size) |
| 79 | return; |
| 80 | |
| 81 | memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); |
| 82 | lppaca_size = new_size; |
| 83 | } |
| 84 | |
| 85 | #else |
| 86 | |
| 87 | static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } |
| 88 | static inline void free_lppacas(void) { } |
| 89 | |
| 90 | #endif /* CONFIG_PPC_BOOK3S */ |
| 91 | |
| 92 | #ifdef CONFIG_PPC_STD_MMU_64 |
| 93 | |
| 94 | /* |
| 95 | * 3 persistent SLBs are registered here. The buffer will be zero |
| 96 | * initially, hence will all be invaild until we actually write them. |
| 97 | * |
| 98 | * If you make the number of persistent SLB entries dynamic, please also |
| 99 | * update PR KVM to flush and restore them accordingly. |
| 100 | */ |
| 101 | static struct slb_shadow *slb_shadow; |
| 102 | |
| 103 | static void __init allocate_slb_shadows(int nr_cpus, int limit) |
| 104 | { |
| 105 | int size = PAGE_ALIGN(sizeof(struct slb_shadow) * nr_cpus); |
| 106 | slb_shadow = __va(memblock_alloc_base(size, PAGE_SIZE, limit)); |
| 107 | memset(slb_shadow, 0, size); |
| 108 | } |
| 109 | |
| 110 | static struct slb_shadow * __init init_slb_shadow(int cpu) |
| 111 | { |
| 112 | struct slb_shadow *s = &slb_shadow[cpu]; |
| 113 | |
| 114 | /* |
| 115 | * When we come through here to initialise boot_paca, the slb_shadow |
| 116 | * buffers are not allocated yet. That's OK, we'll get one later in |
| 117 | * boot, but make sure we don't corrupt memory at 0. |
| 118 | */ |
| 119 | if (!slb_shadow) |
| 120 | return NULL; |
| 121 | |
| 122 | s->persistent = cpu_to_be32(SLB_NUM_BOLTED); |
| 123 | s->buffer_length = cpu_to_be32(sizeof(*s)); |
| 124 | |
| 125 | return s; |
| 126 | } |
| 127 | |
| 128 | #else /* CONFIG_PPC_STD_MMU_64 */ |
| 129 | |
| 130 | static void __init allocate_slb_shadows(int nr_cpus, int limit) { } |
| 131 | |
| 132 | #endif /* CONFIG_PPC_STD_MMU_64 */ |
| 133 | |
| 134 | /* The Paca is an array with one entry per processor. Each contains an |
| 135 | * lppaca, which contains the information shared between the |
| 136 | * hypervisor and Linux. |
| 137 | * On systems with hardware multi-threading, there are two threads |
| 138 | * per processor. The Paca array must contain an entry for each thread. |
| 139 | * The VPD Areas will give a max logical processors = 2 * max physical |
| 140 | * processors. The processor VPD array needs one entry per physical |
| 141 | * processor (not thread). |
| 142 | */ |
| 143 | struct paca_struct *paca; |
| 144 | EXPORT_SYMBOL(paca); |
| 145 | |
| 146 | void __init initialise_paca(struct paca_struct *new_paca, int cpu) |
| 147 | { |
| 148 | #ifdef CONFIG_PPC_BOOK3S |
| 149 | new_paca->lppaca_ptr = new_lppaca(cpu); |
| 150 | #else |
| 151 | new_paca->kernel_pgd = swapper_pg_dir; |
| 152 | #endif |
| 153 | new_paca->lock_token = 0x8000; |
| 154 | new_paca->paca_index = cpu; |
| 155 | new_paca->kernel_toc = kernel_toc_addr(); |
| 156 | new_paca->kernelbase = (unsigned long) _stext; |
| 157 | /* Only set MSR:IR/DR when MMU is initialized */ |
| 158 | new_paca->kernel_msr = MSR_KERNEL & ~(MSR_IR | MSR_DR); |
| 159 | new_paca->hw_cpu_id = 0xffff; |
| 160 | new_paca->kexec_state = KEXEC_STATE_NONE; |
| 161 | new_paca->__current = &init_task; |
| 162 | new_paca->data_offset = 0xfeeeeeeeeeeeeeeeULL; |
| 163 | #ifdef CONFIG_PPC_STD_MMU_64 |
| 164 | new_paca->slb_shadow_ptr = init_slb_shadow(cpu); |
| 165 | #endif /* CONFIG_PPC_STD_MMU_64 */ |
| 166 | |
| 167 | #ifdef CONFIG_PPC_BOOK3E |
| 168 | /* For now -- if we have threads this will be adjusted later */ |
| 169 | new_paca->tcd_ptr = &new_paca->tcd; |
| 170 | #endif |
| 171 | } |
| 172 | |
| 173 | /* Put the paca pointer into r13 and SPRG_PACA */ |
| 174 | void setup_paca(struct paca_struct *new_paca) |
| 175 | { |
| 176 | /* Setup r13 */ |
| 177 | local_paca = new_paca; |
| 178 | |
| 179 | #ifdef CONFIG_PPC_BOOK3E |
| 180 | /* On Book3E, initialize the TLB miss exception frames */ |
| 181 | mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); |
| 182 | #else |
| 183 | /* In HV mode, we setup both HPACA and PACA to avoid problems |
| 184 | * if we do a GET_PACA() before the feature fixups have been |
| 185 | * applied |
| 186 | */ |
| 187 | if (cpu_has_feature(CPU_FTR_HVMODE)) |
| 188 | mtspr(SPRN_SPRG_HPACA, local_paca); |
| 189 | #endif |
| 190 | mtspr(SPRN_SPRG_PACA, local_paca); |
| 191 | |
| 192 | } |
| 193 | |
| 194 | static int __initdata paca_size; |
| 195 | |
| 196 | void __init allocate_pacas(void) |
| 197 | { |
| 198 | u64 limit; |
| 199 | int cpu; |
| 200 | |
| 201 | limit = ppc64_rma_size; |
| 202 | |
| 203 | #ifdef CONFIG_PPC_BOOK3S_64 |
| 204 | /* |
| 205 | * We can't take SLB misses on the paca, and we want to access them |
| 206 | * in real mode, so allocate them within the RMA and also within |
| 207 | * the first segment. |
| 208 | */ |
| 209 | limit = min(0x10000000ULL, limit); |
| 210 | #endif |
| 211 | |
| 212 | paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); |
| 213 | |
| 214 | paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); |
| 215 | memset(paca, 0, paca_size); |
| 216 | |
| 217 | printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", |
| 218 | paca_size, nr_cpu_ids, paca); |
| 219 | |
| 220 | allocate_lppacas(nr_cpu_ids, limit); |
| 221 | |
| 222 | allocate_slb_shadows(nr_cpu_ids, limit); |
| 223 | |
| 224 | /* Can't use for_each_*_cpu, as they aren't functional yet */ |
| 225 | for (cpu = 0; cpu < nr_cpu_ids; cpu++) |
| 226 | initialise_paca(&paca[cpu], cpu); |
| 227 | } |
| 228 | |
| 229 | void __init free_unused_pacas(void) |
| 230 | { |
| 231 | int new_size; |
| 232 | |
| 233 | new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); |
| 234 | |
| 235 | if (new_size >= paca_size) |
| 236 | return; |
| 237 | |
| 238 | memblock_free(__pa(paca) + new_size, paca_size - new_size); |
| 239 | |
| 240 | printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", |
| 241 | paca_size - new_size); |
| 242 | |
| 243 | paca_size = new_size; |
| 244 | |
| 245 | free_lppacas(); |
| 246 | } |