diff options
Diffstat (limited to 'arch/powerpc/kernel/paca.c')
| -rw-r--r-- | arch/powerpc/kernel/paca.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c new file mode 100644 index 00000000..0bb1f986 --- /dev/null +++ b/arch/powerpc/kernel/paca.c @@ -0,0 +1,219 @@ +/* + * c 2001 PPC 64 Team, IBM Corp + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/smp.h> +#include <linux/export.h> +#include <linux/memblock.h> + +#include <asm/lppaca.h> +#include <asm/paca.h> +#include <asm/sections.h> +#include <asm/pgtable.h> +#include <asm/kexec.h> + +/* This symbol is provided by the linker - let it fill in the paca + * field correctly */ +extern unsigned long __toc_start; + +#ifdef CONFIG_PPC_BOOK3S + +/* + * The structure which the hypervisor knows about - this structure + * should not cross a page boundary. The vpa_init/register_vpa call + * is now known to fail if the lppaca structure crosses a page + * boundary. The lppaca is also used on POWER5 pSeries boxes. + * The lppaca is 640 bytes long, and cannot readily + * change since the hypervisor knows its layout, so a 1kB alignment + * will suffice to ensure that it doesn't cross a page boundary. + */ +struct lppaca lppaca[] = { + [0 ... (NR_LPPACAS-1)] = { + .desc = 0xd397d781, /* "LpPa" */ + .size = sizeof(struct lppaca), + .dyn_proc_status = 2, + .decr_val = 0x00ff0000, + .fpregs_in_use = 1, + .end_of_quantum = 0xfffffffffffffffful, + .slb_count = 64, + .vmxregs_in_use = 0, + .page_ins = 0, + }, +}; + +static struct lppaca *extra_lppacas; +static long __initdata lppaca_size; + +static void allocate_lppacas(int nr_cpus, unsigned long limit) +{ + if (nr_cpus <= NR_LPPACAS) + return; + + lppaca_size = PAGE_ALIGN(sizeof(struct lppaca) * + (nr_cpus - NR_LPPACAS)); + extra_lppacas = __va(memblock_alloc_base(lppaca_size, + PAGE_SIZE, limit)); +} + +static struct lppaca *new_lppaca(int cpu) +{ + struct lppaca *lp; + + if (cpu < NR_LPPACAS) + return &lppaca[cpu]; + + lp = extra_lppacas + (cpu - NR_LPPACAS); + *lp = lppaca[0]; + + return lp; +} + +static void free_lppacas(void) +{ + long new_size = 0, nr; + + if (!lppaca_size) + return; + nr = num_possible_cpus() - NR_LPPACAS; + if (nr > 0) + new_size = PAGE_ALIGN(nr * sizeof(struct lppaca)); + if (new_size >= lppaca_size) + return; + + memblock_free(__pa(extra_lppacas) + new_size, lppaca_size - new_size); + lppaca_size = new_size; +} + +#else + +static inline void allocate_lppacas(int nr_cpus, unsigned long limit) { } +static inline void free_lppacas(void) { } + +#endif /* CONFIG_PPC_BOOK3S */ + +#ifdef CONFIG_PPC_STD_MMU_64 + +/* + * 3 persistent SLBs are registered here. The buffer will be zero + * initially, hence will all be invaild until we actually write them. + */ +struct slb_shadow slb_shadow[] __cacheline_aligned = { + [0 ... (NR_CPUS-1)] = { + .persistent = SLB_NUM_BOLTED, + .buffer_length = sizeof(struct slb_shadow), + }, +}; + +#endif /* CONFIG_PPC_STD_MMU_64 */ + +/* The Paca is an array with one entry per processor. Each contains an + * lppaca, which contains the information shared between the + * hypervisor and Linux. + * On systems with hardware multi-threading, there are two threads + * per processor. The Paca array must contain an entry for each thread. + * The VPD Areas will give a max logical processors = 2 * max physical + * processors. The processor VPD array needs one entry per physical + * processor (not thread). + */ +struct paca_struct *paca; +EXPORT_SYMBOL(paca); + +struct paca_struct boot_paca; + +void __init initialise_paca(struct paca_struct *new_paca, int cpu) +{ + /* The TOC register (GPR2) points 32kB into the TOC, so that 64kB + * of the TOC can be addressed using a single machine instruction. + */ + unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL; + +#ifdef CONFIG_PPC_BOOK3S + new_paca->lppaca_ptr = new_lppaca(cpu); +#else + new_paca->kernel_pgd = swapper_pg_dir; +#endif + new_paca->lock_token = 0x8000; + new_paca->paca_index = cpu; + new_paca->kernel_toc = kernel_toc; + new_paca->kernelbase = (unsigned long) _stext; + new_paca->kernel_msr = MSR_KERNEL; + new_paca->hw_cpu_id = 0xffff; + new_paca->kexec_state = KEXEC_STATE_NONE; + new_paca->__current = &init_task; +#ifdef CONFIG_PPC_STD_MMU_64 + new_paca->slb_shadow_ptr = &slb_shadow[cpu]; +#endif /* CONFIG_PPC_STD_MMU_64 */ +} + +/* Put the paca pointer into r13 and SPRG_PACA */ +void setup_paca(struct paca_struct *new_paca) +{ + /* Setup r13 */ + local_paca = new_paca; + +#ifdef CONFIG_PPC_BOOK3E + /* On Book3E, initialize the TLB miss exception frames */ + mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb); +#else + /* In HV mode, we setup both HPACA and PACA to avoid problems + * if we do a GET_PACA() before the feature fixups have been + * applied + */ + if (cpu_has_feature(CPU_FTR_HVMODE)) + mtspr(SPRN_SPRG_HPACA, local_paca); +#endif + mtspr(SPRN_SPRG_PACA, local_paca); + +} + +static int __initdata paca_size; + +void __init allocate_pacas(void) +{ + int cpu, limit; + + /* + * We can't take SLB misses on the paca, and we want to access them + * in real mode, so allocate them within the RMA and also within + * the first segment. + */ + limit = min(0x10000000ULL, ppc64_rma_size); + + paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); + + paca = __va(memblock_alloc_base(paca_size, PAGE_SIZE, limit)); + memset(paca, 0, paca_size); + + printk(KERN_DEBUG "Allocated %u bytes for %d pacas at %p\n", + paca_size, nr_cpu_ids, paca); + + allocate_lppacas(nr_cpu_ids, limit); + + /* Can't use for_each_*_cpu, as they aren't functional yet */ + for (cpu = 0; cpu < nr_cpu_ids; cpu++) + initialise_paca(&paca[cpu], cpu); +} + +void __init free_unused_pacas(void) +{ + int new_size; + + new_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpu_ids); + + if (new_size >= paca_size) + return; + + memblock_free(__pa(paca) + new_size, paca_size - new_size); + + printk(KERN_DEBUG "Freed %u bytes for unused pacas\n", + paca_size - new_size); + + paca_size = new_size; + + free_lppacas(); +} |