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/lmb.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_CPUS-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 #endif /* CONFIG_PPC_BOOK3S */ 53 54 #ifdef CONFIG_PPC_STD_MMU_64 55 56 /* 57 * 3 persistent SLBs are registered here. The buffer will be zero 58 * initially, hence will all be invaild until we actually write them. 59 */ 60 struct slb_shadow slb_shadow[] __cacheline_aligned = { 61 [0 ... (NR_CPUS-1)] = { 62 .persistent = SLB_NUM_BOLTED, 63 .buffer_length = sizeof(struct slb_shadow), 64 }, 65 }; 66 67 #endif /* CONFIG_PPC_STD_MMU_64 */ 68 69 /* The Paca is an array with one entry per processor. Each contains an 70 * lppaca, which contains the information shared between the 71 * hypervisor and Linux. 72 * On systems with hardware multi-threading, there are two threads 73 * per processor. The Paca array must contain an entry for each thread. 74 * The VPD Areas will give a max logical processors = 2 * max physical 75 * processors. The processor VPD array needs one entry per physical 76 * processor (not thread). 77 */ 78 struct paca_struct *paca; 79 EXPORT_SYMBOL(paca); 80 81 struct paca_struct boot_paca; 82 83 void __init initialise_paca(struct paca_struct *new_paca, int cpu) 84 { 85 /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB 86 * of the TOC can be addressed using a single machine instruction. 87 */ 88 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; 89 90 #ifdef CONFIG_PPC_BOOK3S 91 new_paca->lppaca_ptr = &lppaca[cpu]; 92 #else 93 new_paca->kernel_pgd = swapper_pg_dir; 94 #endif 95 new_paca->lock_token = 0x8000; 96 new_paca->paca_index = cpu; 97 new_paca->kernel_toc = kernel_toc; 98 new_paca->kernelbase = (unsigned long) _stext; 99 new_paca->kernel_msr = MSR_KERNEL; 100 new_paca->hw_cpu_id = 0xffff; 101 new_paca->kexec_state = KEXEC_STATE_NONE; 102 new_paca->__current = &init_task; 103 #ifdef CONFIG_PPC_STD_MMU_64 104 new_paca->slb_shadow_ptr = &slb_shadow[cpu]; 105 #endif /* CONFIG_PPC_STD_MMU_64 */ 106 } 107 108 static int __initdata paca_size; 109 110 void __init allocate_pacas(void) 111 { 112 int nr_cpus, cpu, limit; 113 114 /* 115 * We can't take SLB misses on the paca, and we want to access them 116 * in real mode, so allocate them within the RMA and also within 117 * the first segment. On iSeries they must be within the area mapped 118 * by the HV, which is HvPagesToMap * HVPAGESIZE bytes. 119 */ 120 limit = min(0x10000000ULL, lmb.rmo_size); 121 if (firmware_has_feature(FW_FEATURE_ISERIES)) 122 limit = min(limit, HvPagesToMap * HVPAGESIZE); 123 124 nr_cpus = NR_CPUS; 125 /* On iSeries we know we can never have more than 64 cpus */ 126 if (firmware_has_feature(FW_FEATURE_ISERIES)) 127 nr_cpus = min(64, nr_cpus); 128 129 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpus); 130 131 paca = __va(lmb_alloc_base(paca_size, PAGE_SIZE, limit)); 132 memset(paca, 0, paca_size); 133 134 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", 135 paca_size, nr_cpus, paca); 136 137 /* Can't use for_each_*_cpu, as they aren't functional yet */ 138 for (cpu = 0; cpu < nr_cpus; cpu++) 139 initialise_paca(&paca[cpu], cpu); 140 } 141 142 void __init free_unused_pacas(void) 143 { 144 int new_size; 145 146 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus()); 147 148 if (new_size >= paca_size) 149 return; 150 151 lmb_free(__pa(paca) + new_size, paca_size - new_size); 152 153 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", 154 paca_size - new_size); 155 156 paca_size = new_size; 157 } 158