kernel_optimize_test/arch/powerpc/kernel/paca.c
Benjamin Herrenschmidt cd3db0c4ca memblock: Remove rmo_size, burry it in arch/powerpc where it belongs
The RMA (RMO is a misnomer) is a concept specific to ppc64 (in fact
server ppc64 though I hijack it on embedded ppc64 for similar purposes)
and represents the area of memory that can be accessed in real mode
(aka with MMU off), or on embedded, from the exception vectors (which
is bolted in the TLB) which pretty much boils down to the same thing.

We take that out of the generic MEMBLOCK data structure and move it into
arch/powerpc where it belongs, renaming it to "RMA" while at it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:08 +10:00

158 lines
4.6 KiB
C

/*
* 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, ppc64_rma_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;
}