powerpc/44x: Support 16K/64K base page sizes on 44x

This adds support for 16k and 64k page sizes on PowerPC 44x processors.

The PGDIR table is much smaller than a page when using 16k or 64k
pages (512 and 32 bytes respectively) so we allocate the PGDIR with
kzalloc() instead of __get_free_pages().

One PTE table covers rather a large memory area when using 16k or 64k
pages (32MB or 512MB respectively), so we can easily put FIXMAP and
PKMAP in the area covered by one PTE table.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vladimir Panfilov <pvr@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Ilya Yanok 2008-12-11 04:55:41 +03:00 committed by Paul Mackerras
parent 6ca4f7494b
commit ca9153a3a2
10 changed files with 130 additions and 48 deletions

View file

@ -405,23 +405,53 @@ config PPC_HAS_HASH_64K
depends on PPC64
default n
config PPC_64K_PAGES
bool "64k page size"
depends on PPC64
select PPC_HAS_HASH_64K
choice
prompt "Page size"
default PPC_4K_PAGES
help
This option changes the kernel logical page size to 64k. On machines
without processor support for 64k pages, the kernel will simulate
them by loading each individual 4k page on demand transparently,
while on hardware with such support, it will be used to map
normal application pages.
Select the kernel logical page size. Increasing the page size
will reduce software overhead at each page boundary, allow
hardware prefetch mechanisms to be more effective, and allow
larger dma transfers increasing IO efficiency and reducing
overhead. However the utilization of memory will increase.
For example, each cached file will using a multiple of the
page size to hold its contents and the difference between the
end of file and the end of page is wasted.
Some dedicated systems, such as software raid serving with
accelerated calculations, have shown significant increases.
If you configure a 64 bit kernel for 64k pages but the
processor does not support them, then the kernel will simulate
them with 4k pages, loading them on demand, but with the
reduced software overhead and larger internal fragmentation.
For the 32 bit kernel, a large page option will not be offered
unless it is supported by the configured processor.
If unsure, choose 4K_PAGES.
config PPC_4K_PAGES
bool "4k page size"
config PPC_16K_PAGES
bool "16k page size" if 44x
config PPC_64K_PAGES
bool "64k page size" if 44x || PPC_STD_MMU_64
select PPC_HAS_HASH_64K if PPC_STD_MMU_64
endchoice
config FORCE_MAX_ZONEORDER
int "Maximum zone order"
range 9 64 if PPC_64K_PAGES
default "9" if PPC_64K_PAGES
range 13 64 if PPC64 && !PPC_64K_PAGES
default "13" if PPC64 && !PPC_64K_PAGES
range 9 64 if PPC_STD_MMU_64 && PPC_64K_PAGES
default "9" if PPC_STD_MMU_64 && PPC_64K_PAGES
range 13 64 if PPC_STD_MMU_64 && !PPC_64K_PAGES
default "13" if PPC_STD_MMU_64 && !PPC_64K_PAGES
range 9 64 if PPC_STD_MMU_32 && PPC_16K_PAGES
default "9" if PPC_STD_MMU_32 && PPC_16K_PAGES
range 7 64 if PPC_STD_MMU_32 && PPC_64K_PAGES
default "7" if PPC_STD_MMU_32 && PPC_64K_PAGES
range 11 64
default "11"
help
@ -441,7 +471,7 @@ config FORCE_MAX_ZONEORDER
config PPC_SUBPAGE_PROT
bool "Support setting protections for 4k subpages"
depends on PPC_64K_PAGES
depends on PPC_STD_MMU_64 && PPC_64K_PAGES
help
This option adds support for a system call to allow user programs
to set access permissions (read/write, readonly, or no access)

View file

@ -38,9 +38,24 @@ extern pte_t *pkmap_page_table;
* easily, subsequent pte tables have to be allocated in one physical
* chunk of RAM.
*/
#define LAST_PKMAP (1 << PTE_SHIFT)
#define LAST_PKMAP_MASK (LAST_PKMAP-1)
/*
* We use one full pte table with 4K pages. And with 16K/64K pages pte
* table covers enough memory (32MB and 512MB resp.) that both FIXMAP
* and PKMAP can be placed in single pte table. We use 1024 pages for
* PKMAP in case of 16K/64K pages.
*/
#ifdef CONFIG_PPC_4K_PAGES
#define PKMAP_ORDER PTE_SHIFT
#else
#define PKMAP_ORDER 10
#endif
#define LAST_PKMAP (1 << PKMAP_ORDER)
#ifndef CONFIG_PPC_4K_PAGES
#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
#else
#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
#endif
#define LAST_PKMAP_MASK (LAST_PKMAP-1)
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))

View file

@ -4,6 +4,8 @@
* PPC440 support
*/
#include <asm/page.h>
#define PPC44x_MMUCR_TID 0x000000ff
#define PPC44x_MMUCR_STS 0x00010000
@ -74,4 +76,19 @@ typedef struct {
/* Size of the TLBs used for pinning in lowmem */
#define PPC_PIN_SIZE (1 << 28) /* 256M */
#if (PAGE_SHIFT == 12)
#define PPC44x_TLBE_SIZE PPC44x_TLB_4K
#elif (PAGE_SHIFT == 14)
#define PPC44x_TLBE_SIZE PPC44x_TLB_16K
#elif (PAGE_SHIFT == 16)
#define PPC44x_TLBE_SIZE PPC44x_TLB_64K
#else
#error "Unsupported PAGE_SIZE"
#endif
#define PPC44x_PGD_OFF_SHIFT (32 - PGDIR_SHIFT + PGD_T_LOG2)
#define PPC44x_PGD_OFF_MASK_BIT (PGDIR_SHIFT - PGD_T_LOG2)
#define PPC44x_PTE_ADD_SHIFT (32 - PGDIR_SHIFT + PTE_SHIFT + PTE_T_LOG2)
#define PPC44x_PTE_ADD_MASK_BIT (32 - PTE_T_LOG2 - PTE_SHIFT)
#endif /* _ASM_POWERPC_MMU_44X_H_ */

View file

@ -19,12 +19,15 @@
#include <asm/kdump.h>
/*
* On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software
* On regular PPC32 page size is 4K (but we support 4K/16K/64K pages
* on PPC44x). For PPC64 we support either 4K or 64K software
* page size. When using 64K pages however, whether we are really supporting
* 64K pages in HW or not is irrelevant to those definitions.
*/
#ifdef CONFIG_PPC_64K_PAGES
#if defined(CONFIG_PPC_64K_PAGES)
#define PAGE_SHIFT 16
#elif defined(CONFIG_PPC_16K_PAGES)
#define PAGE_SHIFT 14
#else
#define PAGE_SHIFT 12
#endif
@ -151,7 +154,7 @@ typedef struct { pte_basic_t pte; } pte_t;
/* 64k pages additionally define a bigger "real PTE" type that gathers
* the "second half" part of the PTE for pseudo 64k pages
*/
#ifdef CONFIG_PPC_64K_PAGES
#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
#else
typedef struct { pte_t pte; } real_pte_t;
@ -191,10 +194,10 @@ typedef pte_basic_t pte_t;
#define pte_val(x) (x)
#define __pte(x) (x)
#ifdef CONFIG_PPC_64K_PAGES
#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
#else
typedef unsigned long real_pte_t;
typedef pte_t real_pte_t;
#endif

View file

@ -19,6 +19,8 @@
#define PTE_FLAGS_OFFSET 0
#endif
#define PTE_SHIFT (PAGE_SHIFT - PTE_T_LOG2) /* full page */
#ifndef __ASSEMBLY__
/*
* The basic type of a PTE - 64 bits for those CPUs with > 32 bit
@ -26,10 +28,8 @@
*/
#ifdef CONFIG_PTE_64BIT
typedef unsigned long long pte_basic_t;
#define PTE_SHIFT (PAGE_SHIFT - 3) /* 512 ptes per page */
#else
typedef unsigned long pte_basic_t;
#define PTE_SHIFT (PAGE_SHIFT - 2) /* 1024 ptes per page */
#endif
struct page;
@ -39,6 +39,9 @@ extern void copy_page(void *to, void *from);
#include <asm-generic/page.h>
#define PGD_T_LOG2 (__builtin_ffs(sizeof(pgd_t)) - 1)
#define PTE_T_LOG2 (__builtin_ffs(sizeof(pte_t)) - 1)
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_PAGE_32_H */

View file

@ -380,6 +380,10 @@ int main(void)
DEFINE(VCPU_FAULT_DEAR, offsetof(struct kvm_vcpu, arch.fault_dear));
DEFINE(VCPU_FAULT_ESR, offsetof(struct kvm_vcpu, arch.fault_esr));
#endif
#ifdef CONFIG_44x
DEFINE(PGD_T_LOG2, PGD_T_LOG2);
DEFINE(PTE_T_LOG2, PTE_T_LOG2);
#endif
return 0;
}

View file

@ -402,12 +402,14 @@ interrupt_base:
rlwimi r13,r12,10,30,30
/* Load the PTE */
rlwinm r12, r10, 13, 19, 29 /* Compute pgdir/pmd offset */
/* Compute pgdir/pmd offset */
rlwinm r12, r10, PPC44x_PGD_OFF_SHIFT, PPC44x_PGD_OFF_MASK_BIT, 29
lwzx r11, r12, r11 /* Get pgd/pmd entry */
rlwinm. r12, r11, 0, 0, 20 /* Extract pt base address */
beq 2f /* Bail if no table */
rlwimi r12, r10, 23, 20, 28 /* Compute pte address */
/* Compute pte address */
rlwimi r12, r10, PPC44x_PTE_ADD_SHIFT, PPC44x_PTE_ADD_MASK_BIT, 28
lwz r11, 0(r12) /* Get high word of pte entry */
lwz r12, 4(r12) /* Get low word of pte entry */
@ -496,12 +498,14 @@ tlb_44x_patch_hwater_D:
/* Make up the required permissions */
li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_HWEXEC
rlwinm r12, r10, 13, 19, 29 /* Compute pgdir/pmd offset */
/* Compute pgdir/pmd offset */
rlwinm r12, r10, PPC44x_PGD_OFF_SHIFT, PPC44x_PGD_OFF_MASK_BIT, 29
lwzx r11, r12, r11 /* Get pgd/pmd entry */
rlwinm. r12, r11, 0, 0, 20 /* Extract pt base address */
beq 2f /* Bail if no table */
rlwimi r12, r10, 23, 20, 28 /* Compute pte address */
/* Compute pte address */
rlwimi r12, r10, PPC44x_PTE_ADD_SHIFT, PPC44x_PTE_ADD_MASK_BIT, 28
lwz r11, 0(r12) /* Get high word of pte entry */
lwz r12, 4(r12) /* Get low word of pte entry */
@ -565,15 +569,16 @@ tlb_44x_patch_hwater_I:
*/
finish_tlb_load:
/* Combine RPN & ERPN an write WS 0 */
rlwimi r11,r12,0,0,19
rlwimi r11,r12,0,0,31-PAGE_SHIFT
tlbwe r11,r13,PPC44x_TLB_XLAT
/*
* Create WS1. This is the faulting address (EPN),
* page size, and valid flag.
*/
li r11,PPC44x_TLB_VALID | PPC44x_TLB_4K
rlwimi r10,r11,0,20,31 /* Insert valid and page size*/
li r11,PPC44x_TLB_VALID | PPC44x_TLBE_SIZE
/* Insert valid and page size */
rlwimi r10,r11,0,PPC44x_PTE_ADD_MASK_BIT,31
tlbwe r10,r13,PPC44x_TLB_PAGEID /* Write PAGEID */
/* And WS 2 */
@ -645,12 +650,12 @@ _GLOBAL(set_context)
* goes at the beginning of the data segment, which is page-aligned.
*/
.data
.align 12
.align PAGE_SHIFT
.globl sdata
sdata:
.globl empty_zero_page
empty_zero_page:
.space 4096
.space PAGE_SIZE
/*
* To support >32-bit physical addresses, we use an 8KB pgdir.

View file

@ -426,8 +426,8 @@ _GLOBAL(__flush_dcache_icache)
BEGIN_FTR_SECTION
blr
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
rlwinm r3,r3,0,0,19 /* Get page base address */
li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
rlwinm r3,r3,0,0,31-PAGE_SHIFT /* Get page base address */
li r4,PAGE_SIZE/L1_CACHE_BYTES /* Number of lines in a page */
mtctr r4
mr r6,r3
0: dcbst 0,r3 /* Write line to ram */
@ -467,8 +467,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
rlwinm r0,r10,0,28,26 /* clear DR */
mtmsr r0
isync
rlwinm r3,r3,0,0,19 /* Get page base address */
li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
rlwinm r3,r3,0,0,31-PAGE_SHIFT /* Get page base address */
li r4,PAGE_SIZE/L1_CACHE_BYTES /* Number of lines in a page */
mtctr r4
mr r6,r3
0: dcbst 0,r3 /* Write line to ram */
@ -492,7 +492,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
* void clear_pages(void *page, int order) ;
*/
_GLOBAL(clear_pages)
li r0,4096/L1_CACHE_BYTES
li r0,PAGE_SIZE/L1_CACHE_BYTES
slw r0,r0,r4
mtctr r0
#ifdef CONFIG_8xx
@ -550,7 +550,7 @@ _GLOBAL(copy_page)
dcbt r5,r4
li r11,L1_CACHE_BYTES+4
#endif /* MAX_COPY_PREFETCH */
li r0,4096/L1_CACHE_BYTES - MAX_COPY_PREFETCH
li r0,PAGE_SIZE/L1_CACHE_BYTES - MAX_COPY_PREFETCH
crclr 4*cr0+eq
2:
mtctr r0

View file

@ -68,24 +68,29 @@ extern unsigned long p_mapped_by_tlbcam(unsigned long pa);
#define p_mapped_by_tlbcam(x) (0UL)
#endif /* HAVE_TLBCAM */
#ifdef CONFIG_PTE_64BIT
/* Some processors use an 8kB pgdir because they have 8-byte Linux PTEs. */
#define PGDIR_ORDER 1
#else
#define PGDIR_ORDER 0
#endif
#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *ret;
ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER);
/* pgdir take page or two with 4K pages and a page fraction otherwise */
#ifndef CONFIG_PPC_4K_PAGES
ret = (pgd_t *)kzalloc(1 << PGDIR_ORDER, GFP_KERNEL);
#else
ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
PGDIR_ORDER - PAGE_SHIFT);
#endif
return ret;
}
void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
free_pages((unsigned long)pgd, PGDIR_ORDER);
#ifndef CONFIG_PPC_4K_PAGES
kfree((void *)pgd);
#else
free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
#endif
}
__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
@ -385,7 +390,7 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
#endif /* CONFIG_DEBUG_PAGEALLOC */
static int fixmaps;
unsigned long FIXADDR_TOP = 0xfffff000;
unsigned long FIXADDR_TOP = (-PAGE_SIZE);
EXPORT_SYMBOL(FIXADDR_TOP);
void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)

View file

@ -212,7 +212,7 @@ config PPC_MMU_NOHASH
config PPC_MM_SLICES
bool
default y if HUGETLB_PAGE || PPC_64K_PAGES
default y if HUGETLB_PAGE || (PPC_STD_MMU_64 && PPC_64K_PAGES)
default n
config VIRT_CPU_ACCOUNTING