Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
Scott Wood writes:
> On Wed, 2019-02-20 at 01:14 +1100, Michael Ellerman wrote:
>> Christophe Leroy writes:
>>
>> > On 02/08/2019 12:34 PM, Michael Ellerman wrote:
>> > > In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
>> > > 64Kpage size from 64bit booke") we dropped the 64K page size support
>> > > from the 64-bit nohash (Book3E) code.
>> > >
>> > > But we didn't update the dependencies of the PPC_64K_PAGES option,
>> > > meaning a randconfig can still trigger this code and cause a build
>> > > breakage, eg:
>> > >arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error
>> > > "Page size not supported"
>> > >arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error
>> > > Unsupported page size
>> > >
>> > > So remove PPC_BOOK3E_64 from the dependencies. This also means we
>> > > don't need to worry about PPC_FSL_BOOK3E, because that was just trying
>> > > to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
>> >
>> > Does it means some cleanup could be done, for instance:
>> >
>> > arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /*
>> > CONFIG_PPC_64K_PAGES */
>> > arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES
>> > */
>> > arch/powerpc/include/asm/nohash/64/slice.h:#endif /*
>> > !CONFIG_PPC_64K_PAGES */
>> > arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES
>> >
>> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
>> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
>> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
>> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
>> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
>>
>> Probably.
>>
>> Some of the FSL chips do support 64K pages at least according to some
>> datasheets. I don't know what would be required to get it working, or if
>> it even works in practice.
>>
>> So it would be nice to get 64K working on those chips, but probably no
>> one has time or motivation to do it. In which case yeah all that code
>> should be removed.
>
> The primary TLB (TLB0) on these chips only supports 4K pages. TLB1 supports
> many different sizes but is much smaller, hardware tablewalk only loads into
> TLB0, etc.
Aha thanks. I wondered if there was some reason for it.
So that makes it sound much less interesting, meaning all that 64K page
code should go.
cheers
Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
On Wed, 2019-02-20 at 01:14 +1100, Michael Ellerman wrote:
> Christophe Leroy writes:
>
> > On 02/08/2019 12:34 PM, Michael Ellerman wrote:
> > > In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
> > > 64Kpage size from 64bit booke") we dropped the 64K page size support
> > > from the 64-bit nohash (Book3E) code.
> > >
> > > But we didn't update the dependencies of the PPC_64K_PAGES option,
> > > meaning a randconfig can still trigger this code and cause a build
> > > breakage, eg:
> > >arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error
> > > "Page size not supported"
> > >arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error
> > > Unsupported page size
> > >
> > > So remove PPC_BOOK3E_64 from the dependencies. This also means we
> > > don't need to worry about PPC_FSL_BOOK3E, because that was just trying
> > > to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
> >
> > Does it means some cleanup could be done, for instance:
> >
> > arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES
> > arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /*
> > CONFIG_PPC_64K_PAGES */
> > arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES
> > arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES
> > arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES
> > */
> > arch/powerpc/include/asm/nohash/64/slice.h:#endif /*
> > !CONFIG_PPC_64K_PAGES */
> > arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES
> >
> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
>
> Probably.
>
> Some of the FSL chips do support 64K pages at least according to some
> datasheets. I don't know what would be required to get it working, or if
> it even works in practice.
>
> So it would be nice to get 64K working on those chips, but probably no
> one has time or motivation to do it. In which case yeah all that code
> should be removed.
The primary TLB (TLB0) on these chips only supports 4K pages. TLB1 supports
many different sizes but is much smaller, hardware tablewalk only loads into
TLB0, etc.
-Scott
Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
Christophe Leroy writes:
> On 02/08/2019 12:34 PM, Michael Ellerman wrote:
>> In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
>> 64Kpage size from 64bit booke") we dropped the 64K page size support
>> from the 64-bit nohash (Book3E) code.
>>
>> But we didn't update the dependencies of the PPC_64K_PAGES option,
>> meaning a randconfig can still trigger this code and cause a build
>> breakage, eg:
>>arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error "Page
>> size not supported"
>>arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error
>> Unsupported page size
>>
>> So remove PPC_BOOK3E_64 from the dependencies. This also means we
>> don't need to worry about PPC_FSL_BOOK3E, because that was just trying
>> to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
>
> Does it means some cleanup could be done, for instance:
>
> arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /*
> CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/64/slice.h:#endif /*
> !CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES
>
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
Probably.
Some of the FSL chips do support 64K pages at least according to some
datasheets. I don't know what would be required to get it working, or if
it even works in practice.
So it would be nice to get 64K working on those chips, but probably no
one has time or motivation to do it. In which case yeah all that code
should be removed.
cheers
Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
On Fri, 2019-02-08 at 13:01 +, Christophe Leroy wrote:
>
> On 02/08/2019 12:34 PM, Michael Ellerman wrote:
> > In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
> > 64Kpage size from 64bit booke") we dropped the 64K page size support
> > from the 64-bit nohash (Book3E) code.
> >
> > But we didn't update the dependencies of the PPC_64K_PAGES option,
> > meaning a randconfig can still trigger this code and cause a build
> > breakage, eg:
> >arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error "Page
> > size not supported"
> >arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error
> > Unsupported page size
> >
> > So remove PPC_BOOK3E_64 from the dependencies. This also means we
> > don't need to worry about PPC_FSL_BOOK3E, because that was just trying
> > to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
>
> Does it means some cleanup could be done, for instance:
>
> arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /*
> CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/64/slice.h:#endif /*
> !CONFIG_PPC_64K_PAGES */
> arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES
>
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
> arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
> arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
More generally, if fsl is the only supported book3e platform and that's not
expected to change, everything in tlb_low_64e.S except the bolted and e6500
variants could go away.
-Scott
Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
On 02/08/2019 12:34 PM, Michael Ellerman wrote:
In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
64Kpage size from 64bit booke") we dropped the 64K page size support
from the 64-bit nohash (Book3E) code.
But we didn't update the dependencies of the PPC_64K_PAGES option,
meaning a randconfig can still trigger this code and cause a build
breakage, eg:
arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error "Page size not
supported"
arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error
Unsupported page size
So remove PPC_BOOK3E_64 from the dependencies. This also means we
don't need to worry about PPC_FSL_BOOK3E, because that was just trying
to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
Does it means some cleanup could be done, for instance:
arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES
arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /*
CONFIG_PPC_64K_PAGES */
arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES */
arch/powerpc/include/asm/nohash/64/slice.h:#endif /*
!CONFIG_PPC_64K_PAGES */
arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */
arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES
arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES
Christophe
Signed-off-by: Michael Ellerman
---
arch/powerpc/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3f237ffa0649..7a16b8a7b54b 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -694,7 +694,7 @@ config PPC_16K_PAGES
config PPC_64K_PAGES
bool "64k page size"
- depends on !PPC_FSL_BOOK3E && (44x || PPC_BOOK3S_64 || PPC_BOOK3E_64)
+ depends on 44x || PPC_BOOK3S_64
select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
config PPC_256K_PAGES
[PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64
In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported
64Kpage size from 64bit booke") we dropped the 64K page size support
from the 64-bit nohash (Book3E) code.
But we didn't update the dependencies of the PPC_64K_PAGES option,
meaning a randconfig can still trigger this code and cause a build
breakage, eg:
arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error "Page size
not supported"
arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error Unsupported
page size
So remove PPC_BOOK3E_64 from the dependencies. This also means we
don't need to worry about PPC_FSL_BOOK3E, because that was just trying
to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case.
Signed-off-by: Michael Ellerman
---
arch/powerpc/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3f237ffa0649..7a16b8a7b54b 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -694,7 +694,7 @@ config PPC_16K_PAGES
config PPC_64K_PAGES
bool "64k page size"
- depends on !PPC_FSL_BOOK3E && (44x || PPC_BOOK3S_64 || PPC_BOOK3E_64)
+ depends on 44x || PPC_BOOK3S_64
select HAVE_ARCH_SOFT_DIRTY if PPC_BOOK3S_64
config PPC_256K_PAGES
--
2.20.1
