Message ID | 200901130149.43588.yur@emcraft.com (mailing list archive) |
---|---|
State | Superseded, archived |
Delegated to: | Josh Boyer |
Headers | show |
On Jan 12, 2009, at 4:49 PM, Yuri Tikhonov wrote: > This patch adds support for 256KB pages on ppc44x-based boards. Another day, another comment. The motivation for reply was the second comment below. > > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig > index 84b8613..18f33ef 100644 > --- a/arch/powerpc/Kconfig > +++ b/arch/powerpc/Kconfig > @@ -443,6 +443,19 @@ config PPC_64K_PAGES > bool "64k page size" if 44x || PPC_STD_MMU_64 > select PPC_HAS_HASH_64K if PPC_STD_MMU_64 > > +config PPC_256K_PAGES > + bool "256k page size" if 44x > + depends on !STDBINUTILS && !SHMEM depends on !STDBINUTILS && (!SHMEM || BROKEN) to identify that it is not fundamentally incompatable just not a chance of working without other changes. > + help > + Make the page size 256k. > + > + As the ELF standard only requires alignment to support page > + sizes up to 64k, you will need to compile all of your user > + space applications with a non-standard binutils settings > + (see the STDBINUTILS description for details). > + > + Say N unless you know what you are doing. > + > endchoice > > config FORCE_MAX_ZONEORDER > diff --git a/arch/powerpc/platforms/44x/Kconfig > b/arch/powerpc/platforms/44x/Kconfig > index 3496bc0..d02e8c8 100644 > --- a/arch/powerpc/platforms/44x/Kconfig > +++ b/arch/powerpc/platforms/44x/Kconfig > @@ -214,6 +214,18 @@ config 440SPe > bool > select IBM_NEW_EMAC_EMAC4 > > +config STDBINUTILS > + bool "Using standard binutils settings" > + depends on 44x > + default y I think this should be config STDBINUTILS bool "Using standard binutils settings" if 44x default y that way we imply that all powerpc users are using the standard binutils instead of only those using a 44x platform. We still get the intended effect of asking the user only on 44x. I haven't looked at the resulting question or config order to see if it makes sense to leave it here or put it closer to the page size. > + help > + Turning this option off allows you to select 256KB PAGE_SIZE on > 44x. > + Note, that kernel will be able to run only those applications, > + which had been compiled using binutils later than 2.17.50.0.3 with > + '-zmax-page-size' set to 256K (the default is 64K). Or, if using > + the older binutils, you can patch them with a trivial patch, which > + changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000. > + > config 460EX > bool > select PPC_FPU > -- > 1.6.0.6 milton
Hello Milton, On Friday, January 16, 2009 you wrote: > On Jan 12, 2009, at 4:49 PM, Yuri Tikhonov wrote: >> This patch adds support for 256KB pages on ppc44x-based boards. > Another day, another comment. The motivation for reply was the second > comment below. >> >> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >> index 84b8613..18f33ef 100644 >> --- a/arch/powerpc/Kconfig >> +++ b/arch/powerpc/Kconfig >> @@ -443,6 +443,19 @@ config PPC_64K_PAGES >> bool "64k page size" if 44x || PPC_STD_MMU_64 >> select PPC_HAS_HASH_64K if PPC_STD_MMU_64 >> >> +config PPC_256K_PAGES >> + bool "256k page size" if 44x >> + depends on !STDBINUTILS && !SHMEM > depends on !STDBINUTILS && (!SHMEM || BROKEN) > to identify that it is not fundamentally incompatable just not a chance > of working without other changes. This makes sense. [..] >> +config STDBINUTILS >> + bool "Using standard binutils settings" >> + depends on 44x >> + default y > I think this should be > config STDBINUTILS > bool "Using standard binutils settings" if 44x > default y > that way we imply that all powerpc users are using the standard > binutils instead of only those using a 44x platform. We still get the > intended effect of asking the user only on 44x. > I haven't looked at the resulting question or config order to see if it > makes sense to leave it here or put it closer to the page size. I'm not sure about this. For 44x platforms - the STDBINUTILS option is reasonable, because it's used in the PAGE_SIZE selection process. But as regarding the other powerpcs the STDBINUTILS option will do nothing, but taking a superfluous string in configs. Are you sure this will be better ? Regards, Yuri -- Yuri Tikhonov, Senior Software Engineer Emcraft Systems, www.emcraft.com
On Jan 16, 2009, at 9:18 AM, Yuri Tikhonov wrote: > On Friday, January 16, 2009 you wrote: >> On Jan 12, 2009, at 4:49 PM, Yuri Tikhonov wrote: > >>> This patch adds support for 256KB pages on ppc44x-based boards. > > >>> +config STDBINUTILS >>> + bool "Using standard binutils settings" >>> + depends on 44x >>> + default y > > >> I think this should be > >> config STDBINUTILS >> bool "Using standard binutils settings" if 44x >> default y > >> that way we imply that all powerpc users are using the standard >> binutils instead of only those using a 44x platform. We still get the >> intended effect of asking the user only on 44x. > >> I haven't looked at the resulting question or config order to see if >> it >> makes sense to leave it here or put it closer to the page size. > > I'm not sure about this. For 44x platforms - the STDBINUTILS option > is reasonable, because it's used in the PAGE_SIZE selection process. > But as regarding the other powerpcs the STDBINUTILS option will do > nothing, but taking a superfluous string in configs. Are you sure this > will be better ? Ok I tried this out in menuconfig. You are right that the depends on makes sense as it removes the option from the config file as not relevant. But right now to enable 256K pages one has to go to platform setup to find this dependency, then has to go to general setup to find the shmem option at the bottom of the list in the embedded/expert section, then finally go to the kernel options menu to finally choose the page size. Moving this question just before the page size choice removes one of those hidden menu, so I suggest that it be moved to just before the option that it allow be selected. milton
On Sat, Jan 17, 2009 at 08:32:25PM -0600, Milton Miller wrote: > On Jan 16, 2009, at 9:18 AM, Yuri Tikhonov wrote: >> On Friday, January 16, 2009 you wrote: >>> On Jan 12, 2009, at 4:49 PM, Yuri Tikhonov wrote: >> >>>> This patch adds support for 256KB pages on ppc44x-based boards. >> >> >>>> +config STDBINUTILS >>>> + bool "Using standard binutils settings" >>>> + depends on 44x >>>> + default y >> >> >>> I think this should be >> >>> config STDBINUTILS >>> bool "Using standard binutils settings" if 44x >>> default y >> >>> that way we imply that all powerpc users are using the standard >>> binutils instead of only those using a 44x platform. We still get the >>> intended effect of asking the user only on 44x. >> >>> I haven't looked at the resulting question or config order to see if >>> it >>> makes sense to leave it here or put it closer to the page size. >> >> I'm not sure about this. For 44x platforms - the STDBINUTILS option >> is reasonable, because it's used in the PAGE_SIZE selection process. >> But as regarding the other powerpcs the STDBINUTILS option will do >> nothing, but taking a superfluous string in configs. Are you sure this >> will be better ? > > > Ok I tried this out in menuconfig. You are right that the depends on > makes sense as it removes the option from the config file as not > relevant. But right now to enable 256K pages one has to go to platform > setup to find this dependency, then has to go to general setup to find > the shmem option at the bottom of the list in the embedded/expert > section, then finally go to the kernel options menu to finally choose > the page size. Which is fine with me. This is for people that really know what they're doing, so making it harder to enable isn't really a bad thing. josh
On Sunday, January 18, 2009 you wrote: > Ok I tried this out in menuconfig. You are right that the depends on > makes sense as it removes the option from the config file as not > relevant. But right now to enable 256K pages one has to go to platform > setup to find this dependency, then has to go to general setup to find > the shmem option at the bottom of the list in the embedded/expert > section, then finally go to the kernel options menu to finally choose > the page size. > Moving this question just before the page size choice removes one of > those hidden menu, so I suggest that it be moved to just before the > option that it allow be selected. Right, it'll me more convenient. My [v5] patch addresses this. Regards, Yuri -- Yuri Tikhonov, Senior Software Engineer Emcraft Systems, www.emcraft.com
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 84b8613..18f33ef 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -443,6 +443,19 @@ config PPC_64K_PAGES bool "64k page size" if 44x || PPC_STD_MMU_64 select PPC_HAS_HASH_64K if PPC_STD_MMU_64 +config PPC_256K_PAGES + bool "256k page size" if 44x + depends on !STDBINUTILS && !SHMEM + help + Make the page size 256k. + + As the ELF standard only requires alignment to support page + sizes up to 64k, you will need to compile all of your user + space applications with a non-standard binutils settings + (see the STDBINUTILS description for details). + + Say N unless you know what you are doing. + endchoice config FORCE_MAX_ZONEORDER @@ -455,6 +468,8 @@ config FORCE_MAX_ZONEORDER 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 5 64 if PPC_STD_MMU_32 && PPC_256K_PAGES + default "5" if PPC_STD_MMU_32 && PPC_256K_PAGES range 11 64 default "11" help diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h index 04e4a62..a290759 100644 --- a/arch/powerpc/include/asm/highmem.h +++ b/arch/powerpc/include/asm/highmem.h @@ -39,15 +39,15 @@ extern pte_t *pkmap_page_table; * chunk of RAM. */ /* - * 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. + * We use one full pte table with 4K pages. And with 16K/64K/256K pages pte + * table covers enough memory (32MB/512MB/2GB resp.), so that both FIXMAP + * and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP + * in case of 16K/64K/256K page sizes. */ #ifdef CONFIG_PPC_4K_PAGES #define PKMAP_ORDER PTE_SHIFT #else -#define PKMAP_ORDER 10 +#define PKMAP_ORDER 9 #endif #define LAST_PKMAP (1 << PKMAP_ORDER) #ifndef CONFIG_PPC_4K_PAGES diff --git a/arch/powerpc/include/asm/mmu-44x.h b/arch/powerpc/include/asm/mmu-44x.h index 27cc6fd..3c86576 100644 --- a/arch/powerpc/include/asm/mmu-44x.h +++ b/arch/powerpc/include/asm/mmu-44x.h @@ -83,6 +83,8 @@ typedef struct { #define PPC44x_TLBE_SIZE PPC44x_TLB_16K #elif (PAGE_SHIFT == 16) #define PPC44x_TLBE_SIZE PPC44x_TLB_64K +#elif (PAGE_SHIFT == 18) +#define PPC44x_TLBE_SIZE PPC44x_TLB_256K #else #error "Unsupported PAGE_SIZE" #endif diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index 197d569..32cbf16 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -19,12 +19,14 @@ #include <asm/kdump.h> /* - * On regular PPC32 page size is 4K (but we support 4K/16K/64K pages + * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K 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. */ -#if defined(CONFIG_PPC_64K_PAGES) +#if defined(CONFIG_PPC_256K_PAGES) +#define PAGE_SHIFT 18 +#elif defined(CONFIG_PPC_64K_PAGES) #define PAGE_SHIFT 16 #elif defined(CONFIG_PPC_16K_PAGES) #define PAGE_SHIFT 14 diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h index 1458d95..a0e3f6e 100644 --- a/arch/powerpc/include/asm/page_32.h +++ b/arch/powerpc/include/asm/page_32.h @@ -19,7 +19,11 @@ #define PTE_FLAGS_OFFSET 0 #endif +#ifdef CONFIG_PPC_256K_PAGES +#define PTE_SHIFT (PAGE_SHIFT - PTE_T_LOG2 - 2) /* 1/4 of a page */ +#else #define PTE_SHIFT (PAGE_SHIFT - PTE_T_LOG2) /* full page */ +#endif #ifndef __ASSEMBLY__ /* diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index 9665a26..e04286f 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -12,8 +12,10 @@ /* We have 8k stacks on ppc32 and 16k on ppc64 */ -#ifdef CONFIG_PPC64 +#if defined(CONFIG_PPC64) #define THREAD_SHIFT 14 +#elif defined(CONFIG_PPC_256K_PAGES) +#define THREAD_SHIFT 15 #else #define THREAD_SHIFT 13 #endif diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h index fce2df9..17803ad 100644 --- a/arch/powerpc/kernel/head_booke.h +++ b/arch/powerpc/kernel/head_booke.h @@ -10,6 +10,15 @@ mtspr SPRN_IVOR##vector_number,r26; \ sync +#if (THREAD_SHIFT < 15) +#define ALLOC_STACK_FRAME(reg, val) \ + addi reg,reg,val +#else +#define ALLOC_STACK_FRAME(reg, val) \ + addis reg,reg,val@ha; \ + addi reg,reg,val@l +#endif + #define NORMAL_EXCEPTION_PROLOG \ mtspr SPRN_SPRG0,r10; /* save two registers to work with */\ mtspr SPRN_SPRG1,r11; \ @@ -20,7 +29,7 @@ beq 1f; \ mfspr r1,SPRN_SPRG3; /* if from user, start at top of */\ lwz r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack */\ - addi r1,r1,THREAD_SIZE; \ + ALLOC_STACK_FRAME(r1, THREAD_SIZE); \ 1: subi r1,r1,INT_FRAME_SIZE; /* Allocate an exception frame */\ mr r11,r1; \ stw r10,_CCR(r11); /* save various registers */\ diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig index 3496bc0..d02e8c8 100644 --- a/arch/powerpc/platforms/44x/Kconfig +++ b/arch/powerpc/platforms/44x/Kconfig @@ -214,6 +214,18 @@ config 440SPe bool select IBM_NEW_EMAC_EMAC4 +config STDBINUTILS + bool "Using standard binutils settings" + depends on 44x + default y + help + Turning this option off allows you to select 256KB PAGE_SIZE on 44x. + Note, that kernel will be able to run only those applications, + which had been compiled using binutils later than 2.17.50.0.3 with + '-zmax-page-size' set to 256K (the default is 64K). Or, if using + the older binutils, you can patch them with a trivial patch, which + changes the ELF_MAXPAGESIZE definition from 0x10000 to 0x40000. + config 460EX bool select PPC_FPU