* [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
@ 2010-10-01 21:12 akpm
2010-10-02 1:31 ` Josh Boyer
0 siblings, 1 reply; 6+ messages in thread
From: akpm @ 2010-10-01 21:12 UTC (permalink / raw)
To: benh; +Cc: fujita.tomonori, linuxppc-dev, akpm
From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
arch/powerpc/Kconfig | 3 +++
1 file changed, 3 insertions(+)
diff -puN arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-arch_phys_addr_t_64bit arch/powerpc/Kconfig
--- a/arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-arch_phys_addr_t_64bit
+++ a/arch/powerpc/Kconfig
@@ -16,6 +16,9 @@ config WORD_SIZE
config ARCH_PHYS_ADDR_T_64BIT
def_bool PPC64 || PHYS_64BIT
+config ARCH_DMA_ADDR_T_64BIT
+ def_bool ARCH_PHYS_ADDR_T_64BIT
+
config MMU
bool
default y
_
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
2010-10-01 21:12 [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT akpm
@ 2010-10-02 1:31 ` Josh Boyer
2010-10-02 3:20 ` Benjamin Herrenschmidt
0 siblings, 1 reply; 6+ messages in thread
From: Josh Boyer @ 2010-10-02 1:31 UTC (permalink / raw)
To: akpm; +Cc: fujita.tomonori, linuxppc-dev
On Fri, Oct 1, 2010 at 5:12 PM, <akpm@linux-foundation.org> wrote:
> From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
>
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
>
> =A0arch/powerpc/Kconfig | =A0 =A03 +++
> =A01 file changed, 3 insertions(+)
>
> diff -puN arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-=
arch_phys_addr_t_64bit arch/powerpc/Kconfig
> --- a/arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-arch=
_phys_addr_t_64bit
> +++ a/arch/powerpc/Kconfig
> @@ -16,6 +16,9 @@ config WORD_SIZE
> =A0config ARCH_PHYS_ADDR_T_64BIT
> =A0 =A0 =A0 =A0def_bool PPC64 || PHYS_64BIT
>
> +config ARCH_DMA_ADDR_T_64BIT
> + =A0 =A0 =A0 def_bool ARCH_PHYS_ADDR_T_64BIT
> +
I seemed to have missed what this is about entirely. Is there some
place I can look that describes what that is supposed to do? The PPC
4xx boards set PHYS_ADDR_T_64BIT because the MMU uses 36 bit
addressing, but the CPU is only 32 bits. I want to make sure this DMA
thing isn't going to cause problems.
josh
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
2010-10-02 1:31 ` Josh Boyer
@ 2010-10-02 3:20 ` Benjamin Herrenschmidt
2010-10-02 10:11 ` FUJITA Tomonori
0 siblings, 1 reply; 6+ messages in thread
From: Benjamin Herrenschmidt @ 2010-10-02 3:20 UTC (permalink / raw)
To: Josh Boyer; +Cc: fujita.tomonori, linuxppc-dev, akpm
On Fri, 2010-10-01 at 21:31 -0400, Josh Boyer wrote:
> > +config ARCH_DMA_ADDR_T_64BIT
> > + def_bool ARCH_PHYS_ADDR_T_64BIT
> > +
>
> I seemed to have missed what this is about entirely. Is there some
> place I can look that describes what that is supposed to do? The PPC
> 4xx boards set PHYS_ADDR_T_64BIT because the MMU uses 36 bit
> addressing, but the CPU is only 32 bits. I want to make sure this DMA
> thing isn't going to cause problems.
Yes, we need to test a bit. Our dma_addr_t has remained 32-bit so far
because despite the fact that we've had routinely to deal with >32-bit
physical addresses for MMIO, physical memory support has been
constrained afaik to 32-bit.
We might be better off keeping this as something individual platforms
can select...
Cheers,
Ben.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
2010-10-02 3:20 ` Benjamin Herrenschmidt
@ 2010-10-02 10:11 ` FUJITA Tomonori
2010-10-03 6:20 ` Benjamin Herrenschmidt
0 siblings, 1 reply; 6+ messages in thread
From: FUJITA Tomonori @ 2010-10-02 10:11 UTC (permalink / raw)
To: benh; +Cc: fujita.tomonori, linuxppc-dev, akpm
On Sat, 02 Oct 2010 13:20:54 +1000
Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
> On Fri, 2010-10-01 at 21:31 -0400, Josh Boyer wrote:
> > > +config ARCH_DMA_ADDR_T_64BIT
> > > + def_bool ARCH_PHYS_ADDR_T_64BIT
> > > +
> >
> > I seemed to have missed what this is about entirely. Is there some
> > place I can look that describes what that is supposed to do? The PPC
This patchset unifies dma_addr_t typedef.
> > 4xx boards set PHYS_ADDR_T_64BIT because the MMU uses 36 bit
> > addressing, but the CPU is only 32 bits. I want to make sure this DMA
> > thing isn't going to cause problems.
this patchset changes nothing. Please see below.
> Yes, we need to test a bit. Our dma_addr_t has remained 32-bit so far
> because despite the fact that we've had routinely to deal with >32-bit
> physical addresses for MMIO, physical memory support has been
> constrained afaik to 32-bit.
Really?
The current dma_addr_t is:
#if defined(__powerpc64__) || defined(CONFIG_PHYS_64BIT)
typedef u64 dma_addr_t;
#else
typedef u32 dma_addr_t;
#endif
typedef u64 dma64_addr_t;
I think that this patch doesn't change anything. Or I miss something?
@@ -22,6 +22,9 @@ config WORD_SIZE
config ARCH_PHYS_ADDR_T_64BIT
def_bool PPC64 || PHYS_64BIT
+config ARCH_DMA_ADDR_T_64BIT
+ def_bool ARCH_PHYS_ADDR_T_64BIT
+
config MMU
bool
default y
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
2010-10-02 10:11 ` FUJITA Tomonori
@ 2010-10-03 6:20 ` Benjamin Herrenschmidt
0 siblings, 0 replies; 6+ messages in thread
From: Benjamin Herrenschmidt @ 2010-10-03 6:20 UTC (permalink / raw)
To: FUJITA Tomonori; +Cc: linuxppc-dev, akpm
> Really?
>
> The current dma_addr_t is:
>
> #if defined(__powerpc64__) || defined(CONFIG_PHYS_64BIT)
> typedef u64 dma_addr_t;
> #else
> typedef u32 dma_addr_t;
> #endif
> typedef u64 dma64_addr_t;
-EBRAINFAI ... either I wasn't looking when we changed it or I just
forgot :-) We -used-, I'm pretty sure, to have it always 32-bit :-)
Anyways, doesn't matter. Patch looks good. We can always tweak the
config option if we want to later.
Cheers,
Ben.
>
> I think that this patch doesn't change anything. Or I miss something?
>
> @@ -22,6 +22,9 @@ config WORD_SIZE
> config ARCH_PHYS_ADDR_T_64BIT
> def_bool PPC64 || PHYS_64BIT
>
> +config ARCH_DMA_ADDR_T_64BIT
> + def_bool ARCH_PHYS_ADDR_T_64BIT
> +
> config MMU
> bool
> default y
^ permalink raw reply [flat|nested] 6+ messages in thread
* [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT
@ 2010-10-20 22:56 akpm
0 siblings, 0 replies; 6+ messages in thread
From: akpm @ 2010-10-20 22:56 UTC (permalink / raw)
To: benh; +Cc: fujita.tomonori, linuxppc-dev, akpm
From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
arch/powerpc/Kconfig | 3 +++
1 file changed, 3 insertions(+)
diff -puN arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-arch_phys_addr_t_64bit arch/powerpc/Kconfig
--- a/arch/powerpc/Kconfig~powerpc-enable-arch_dma_addr_t_64bit-with-arch_phys_addr_t_64bit
+++ a/arch/powerpc/Kconfig
@@ -16,6 +16,9 @@ config WORD_SIZE
config ARCH_PHYS_ADDR_T_64BIT
def_bool PPC64 || PHYS_64BIT
+config ARCH_DMA_ADDR_T_64BIT
+ def_bool ARCH_PHYS_ADDR_T_64BIT
+
config MMU
bool
default y
_
^ permalink raw reply [flat|nested] 6+ messages in thread
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2010-10-01 21:12 [patch 1/1] powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT akpm
2010-10-02 1:31 ` Josh Boyer
2010-10-02 3:20 ` Benjamin Herrenschmidt
2010-10-02 10:11 ` FUJITA Tomonori
2010-10-03 6:20 ` Benjamin Herrenschmidt
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2010-10-20 22:56 akpm
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