2 * c 2001 PPC 64 Team, IBM Corp
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.
10 #include <linux/threads.h>
11 #include <linux/module.h>
12 #include <linux/memblock.h>
14 #include <asm/firmware.h>
15 #include <asm/lppaca.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>
23 /* This symbol is provided by the linker - let it fill in the paca
25 extern unsigned long __toc_start;
27 #ifdef CONFIG_PPC_BOOK3S
30 * We only have to have statically allocated lppaca structs on
31 * legacy iSeries, which supports at most 64 cpus.
33 #ifdef CONFIG_PPC_ISERIES
35 #define NR_LPPACAS NR_CPUS
39 #else /* not iSeries */
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.
52 struct lppaca lppaca[] = {
53 [0 ... (NR_LPPACAS-1)] = {
54 .desc = 0xd397d781, /* "LpPa" */
55 .size = sizeof(struct lppaca),
57 .decr_val = 0x00ff0000,
59 .end_of_quantum = 0xfffffffffffffffful,
66 static struct lppaca *extra_lppacas;
67 static long __initdata lppaca_size;
69 static void allocate_lppacas(int nr_cpus, unsigned long limit)
71 if (nr_cpus <= NR_LPPACAS)
74 lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) *
75 (nr_cpus - NR_LPPACAS));
76 extra_lppacas = __va(memblock_alloc_base(lppaca_size,
80 static struct lppaca *new_lppaca(int cpu)
87 lp = extra_lppacas + (cpu - NR_LPPACAS);
93 static void free_lppacas(void)
95 long new_size = 0, nr;
99 nr = num_possible_cpus() - NR_LPPACAS;
101 new_size = PAGE_ALIGN(nr * sizeof(struct lppaca));
102 if (new_size >= lppaca_size)
105 memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size);
106 lppaca_size = new_size;
111 static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { }
112 static inline void free_lppacas(void) { }
114 #endif /* CONFIG_PPC_BOOK3S */
116 #ifdef CONFIG_PPC_STD_MMU_64
119 * 3 persistent SLBs are registered here. The buffer will be zero
120 * initially, hence will all be invaild until we actually write them.
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),
129 #endif /* CONFIG_PPC_STD_MMU_64 */
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).
140 struct paca_struct *paca;
143 struct paca_struct boot_paca;
145 void __init initialise_paca(struct paca_struct *new_paca, int cpu)
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.
150 unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL;
152 #ifdef CONFIG_PPC_BOOK3S
153 new_paca->lppaca_ptr = new_lppaca(cpu);
155 new_paca->kernel_pgd = swapper_pg_dir;
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 */
170 /* Put the paca pointer into r13 and SPRG_PACA */
171 void setup_paca(struct paca_struct *new_paca)
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);
180 static int __initdata paca_size;
182 void __init allocate_pacas(void)
184 int nr_cpus, cpu, limit;
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.
192 limit = min(0x10000000ULL, memblock.rmo_size);
193 if (firmware_has_feature(FW_FEATURE_ISERIES))
194 limit = min(limit, HvPagesToMap * HVPAGESIZE);
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);
201 paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpus);
203 paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit));
204 memset(paca, 0, paca_size);
206 printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n",
207 paca_size, nr_cpus, paca);
209 allocate_lppacas(nr_cpus, limit);
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);
216 void __init free_unused_pacas(void)
220 new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus());
222 if (new_size >= paca_size)
225 memblock_free(__pa(paca) + new_size, paca_size - new_size);
227 printk(KERN_DEBUG "Freed %u bytes for unused pacas\n",
228 paca_size - new_size);
230 paca_size = new_size;