kernel-ark/include/asm-ppc64/paca.h
Benjamin Herrenschmidt 3c726f8dee [PATCH] ppc64: support 64k pages
Adds a new CONFIG_PPC_64K_PAGES which, when enabled, changes the kernel
base page size to 64K.  The resulting kernel still boots on any
hardware.  On current machines with 4K pages support only, the kernel
will maintain 16 "subpages" for each 64K page transparently.

Note that while real 64K capable HW has been tested, the current patch
will not enable it yet as such hardware is not released yet, and I'm
still verifying with the firmware architects the proper to get the
information from the newer hypervisors.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-06 16:56:47 -08:00

122 lines
3.9 KiB
C

#ifndef _PPC64_PACA_H
#define _PPC64_PACA_H
/*
* include/asm-ppc64/paca.h
*
* This control block defines the PACA which defines the processor
* specific data for each logical processor on the system.
* There are some pointers defined that are utilized by PLIC.
*
* 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/config.h>
#include <asm/types.h>
#include <asm/lppaca.h>
#include <asm/iseries/it_lp_reg_save.h>
#include <asm/mmu.h>
register struct paca_struct *local_paca asm("r13");
#define get_paca() local_paca
struct task_struct;
/*
* Defines the layout of the paca.
*
* This structure is not directly accessed by firmware or the service
* processor except for the first two pointers that point to the
* lppaca area and the ItLpRegSave area for this CPU. Both the
* lppaca and ItLpRegSave objects are currently contained within the
* PACA but they do not need to be.
*/
struct paca_struct {
/*
* Because hw_cpu_id, unlike other paca fields, is accessed
* routinely from other CPUs (from the IRQ code), we stick to
* read-only (after boot) fields in the first cacheline to
* avoid cacheline bouncing.
*/
/*
* MAGIC: These first two pointers can't be moved - they're
* accessed by the firmware
*/
struct lppaca *lppaca_ptr; /* Pointer to LpPaca for PLIC */
struct ItLpRegSave *reg_save_ptr; /* Pointer to LpRegSave for PLIC */
/*
* MAGIC: the spinlock functions in arch/ppc64/lib/locks.c
* load lock_token and paca_index with a single lwz
* instruction. They must travel together and be properly
* aligned.
*/
u16 lock_token; /* Constant 0x8000, used in locks */
u16 paca_index; /* Logical processor number */
u32 default_decr; /* Default decrementer value */
u64 kernel_toc; /* Kernel TOC address */
u64 stab_real; /* Absolute address of segment table */
u64 stab_addr; /* Virtual address of segment table */
void *emergency_sp; /* pointer to emergency stack */
s16 hw_cpu_id; /* Physical processor number */
u8 cpu_start; /* At startup, processor spins until */
/* this becomes non-zero. */
/*
* Now, starting in cacheline 2, the exception save areas
*/
/* used for most interrupts/exceptions */
u64 exgen[10] __attribute__((aligned(0x80)));
u64 exmc[10]; /* used for machine checks */
u64 exslb[10]; /* used for SLB/segment table misses
* on the linear mapping */
#ifdef CONFIG_PPC_64K_PAGES
pgd_t *pgdir;
#endif /* CONFIG_PPC_64K_PAGES */
mm_context_t context;
u16 slb_cache[SLB_CACHE_ENTRIES];
u16 slb_cache_ptr;
/*
* then miscellaneous read-write fields
*/
struct task_struct *__current; /* Pointer to current */
u64 kstack; /* Saved Kernel stack addr */
u64 stab_rr; /* stab/slb round-robin counter */
u64 next_jiffy_update_tb; /* TB value for next jiffy update */
u64 saved_r1; /* r1 save for RTAS calls */
u64 saved_msr; /* MSR saved here by enter_rtas */
u8 proc_enabled; /* irq soft-enable flag */
/* not yet used */
u64 exdsi[8]; /* used for linear mapping hash table misses */
/*
* iSeries 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 __attribute__((__aligned__(0x400)));
#ifdef CONFIG_PPC_ISERIES
struct ItLpRegSave reg_save;
#endif
};
extern struct paca_struct paca[];
#endif /* _PPC64_PACA_H */