/*
* 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/threads.h>
#include <linux/module.h>
#include <linux/memblock.h>
#include <asm/firmware.h>
#include <asm/lppaca.h>
#include <asm/paca.h>
#include <asm/sections.h>
#include <asm/pgtable.h>
#include <asm/iseries/lpar_map.h>
#include <asm/iseries/hv_types.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 legacy iSeries and 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_CPUS-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,
},
};
#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 = &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 */
}
static int __initdata paca_size;
void __init allocate_pacas(void)
{
int nr_cpus, 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. On iSeries they must be within the area mapped
* by the HV, which is HvPagesToMap * HVPAGESIZE bytes.
*/
limit = min(0x10000000ULL, memblock.rmo_size);
if (firmware_has_feature(FW_FEATURE_ISERIES))
limit = min(limit, HvPagesToMap * HVPAGESIZE);
nr_cpus = NR_CPUS;
/* On iSeries we know we can never have more than 64 cpus */
if (firmware_has_feature(FW_FEATURE_ISERIES))
nr_cpus = min(64, nr_cpus);
paca_size = PAGE_ALIGN(sizeof(struct paca_struct) * nr_cpus);
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_cpus, paca);
/* Can't use for_each_*_cpu, as they aren't functional yet */
for (cpu = 0; cpu < nr_cpus; cpu++)
initialise_paca(&paca[cpu], cpu);
}
void __init free_unused_pacas(void)
{
int new_size;
new_size = PAGE_ALIGN(sizeof(struct paca_struct) * num_possible_cpus());
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;
}
