Files
android_kernel_xiaomi_sm8450/arch/sparc/include/asm/mmu_64.h
David Miller c460bec78d sparc64: Eliminate PTE table memory wastage.
We've split up the PTE tables so that they take up half a page instead of
a full page.  This is in order to facilitate transparent huge page
support, which works much better if our PMDs cover 4MB instead of 8MB.

What we do is have a one-behind cache for PTE table allocations in the
mm struct.

This logic triggers only on allocations.  For example, we don't try to
keep track of free'd up page table blocks in the style that the s390 port
does.

There were only two slightly annoying aspects to this change:

1) Changing pgtable_t to be a "pte_t *".  There's all of this special
   logic in the TLB free paths that needed adjustments, as did the
   PMD populate interfaces.

2) init_new_context() needs to zap the pointer, since the mm struct
   just gets copied from the parent on fork.

Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:23:05 +09:00

111 lines
3.1 KiB
C

#ifndef __MMU_H
#define __MMU_H
#include <linux/const.h>
#include <asm/page.h>
#include <asm/hypervisor.h>
#define CTX_NR_BITS 13
#define TAG_CONTEXT_BITS ((_AC(1,UL) << CTX_NR_BITS) - _AC(1,UL))
/* UltraSPARC-III+ and later have a feature whereby you can
* select what page size the various Data-TLB instances in the
* chip. In order to gracefully support this, we put the version
* field in a spot outside of the areas of the context register
* where this parameter is specified.
*/
#define CTX_VERSION_SHIFT 22
#define CTX_VERSION_MASK ((~0UL) << CTX_VERSION_SHIFT)
#define CTX_PGSZ_8KB _AC(0x0,UL)
#define CTX_PGSZ_64KB _AC(0x1,UL)
#define CTX_PGSZ_512KB _AC(0x2,UL)
#define CTX_PGSZ_4MB _AC(0x3,UL)
#define CTX_PGSZ_BITS _AC(0x7,UL)
#define CTX_PGSZ0_NUC_SHIFT 61
#define CTX_PGSZ1_NUC_SHIFT 58
#define CTX_PGSZ0_SHIFT 16
#define CTX_PGSZ1_SHIFT 19
#define CTX_PGSZ_MASK ((CTX_PGSZ_BITS << CTX_PGSZ0_SHIFT) | \
(CTX_PGSZ_BITS << CTX_PGSZ1_SHIFT))
#define CTX_PGSZ_BASE CTX_PGSZ_8KB
#define CTX_PGSZ_HUGE CTX_PGSZ_4MB
#define CTX_PGSZ_KERN CTX_PGSZ_4MB
/* Thus, when running on UltraSPARC-III+ and later, we use the following
* PRIMARY_CONTEXT register values for the kernel context.
*/
#define CTX_CHEETAH_PLUS_NUC \
((CTX_PGSZ_KERN << CTX_PGSZ0_NUC_SHIFT) | \
(CTX_PGSZ_BASE << CTX_PGSZ1_NUC_SHIFT))
#define CTX_CHEETAH_PLUS_CTX0 \
((CTX_PGSZ_KERN << CTX_PGSZ0_SHIFT) | \
(CTX_PGSZ_BASE << CTX_PGSZ1_SHIFT))
/* If you want "the TLB context number" use CTX_NR_MASK. If you
* want "the bits I program into the context registers" use
* CTX_HW_MASK.
*/
#define CTX_NR_MASK TAG_CONTEXT_BITS
#define CTX_HW_MASK (CTX_NR_MASK | CTX_PGSZ_MASK)
#define CTX_FIRST_VERSION ((_AC(1,UL) << CTX_VERSION_SHIFT) + _AC(1,UL))
#define CTX_VALID(__ctx) \
(!(((__ctx.sparc64_ctx_val) ^ tlb_context_cache) & CTX_VERSION_MASK))
#define CTX_HWBITS(__ctx) ((__ctx.sparc64_ctx_val) & CTX_HW_MASK)
#define CTX_NRBITS(__ctx) ((__ctx.sparc64_ctx_val) & CTX_NR_MASK)
#ifndef __ASSEMBLY__
#define TSB_ENTRY_ALIGNMENT 16
struct tsb {
unsigned long tag;
unsigned long pte;
} __attribute__((aligned(TSB_ENTRY_ALIGNMENT)));
extern void __tsb_insert(unsigned long ent, unsigned long tag, unsigned long pte);
extern void tsb_flush(unsigned long ent, unsigned long tag);
extern void tsb_init(struct tsb *tsb, unsigned long size);
struct tsb_config {
struct tsb *tsb;
unsigned long tsb_rss_limit;
unsigned long tsb_nentries;
unsigned long tsb_reg_val;
unsigned long tsb_map_vaddr;
unsigned long tsb_map_pte;
};
#define MM_TSB_BASE 0
#ifdef CONFIG_HUGETLB_PAGE
#define MM_TSB_HUGE 1
#define MM_NUM_TSBS 2
#else
#define MM_NUM_TSBS 1
#endif
typedef struct {
spinlock_t lock;
unsigned long sparc64_ctx_val;
unsigned long huge_pte_count;
struct page *pgtable_page;
struct tsb_config tsb_block[MM_NUM_TSBS];
struct hv_tsb_descr tsb_descr[MM_NUM_TSBS];
} mm_context_t;
#endif /* !__ASSEMBLY__ */
#define TSB_CONFIG_TSB 0x00
#define TSB_CONFIG_RSS_LIMIT 0x08
#define TSB_CONFIG_NENTRIES 0x10
#define TSB_CONFIG_REG_VAL 0x18
#define TSB_CONFIG_MAP_VADDR 0x20
#define TSB_CONFIG_MAP_PTE 0x28
#endif /* __MMU_H */