2019-06-13 16:33:25

by Christoph Hellwig

[permalink] [raw]
Subject: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

With the strict dma mask checking introduced with the switch to
the generic DMA direct code common wifi chips on 32-bit powerbooks
stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
to allow them to reliably allocate dma coherent memory.

Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
Reported-by: Aaro Koskinen <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
---
arch/powerpc/include/asm/page.h | 7 +++++++
arch/powerpc/mm/mem.c | 3 ++-
arch/powerpc/platforms/powermac/Kconfig | 1 +
3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index b8286a2013b4..0d52f57fca04 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -319,6 +319,13 @@ struct vm_area_struct;
#endif /* __ASSEMBLY__ */
#include <asm/slice.h>

+/*
+ * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
+ */
+#ifdef CONFIG_PPC32
+#define ARCH_ZONE_DMA_BITS 30
+#else
#define ARCH_ZONE_DMA_BITS 31
+#endif

#endif /* _ASM_POWERPC_PAGE_H */
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index cba29131bccc..2540d3b2588c 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -248,7 +248,8 @@ void __init paging_init(void)
(long int)((top_of_ram - total_ram) >> 20));

#ifdef CONFIG_ZONE_DMA
- max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
+ max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
+ ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
#endif
max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
#ifdef CONFIG_HIGHMEM
diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig
index f834a19ed772..c02d8c503b29 100644
--- a/arch/powerpc/platforms/powermac/Kconfig
+++ b/arch/powerpc/platforms/powermac/Kconfig
@@ -7,6 +7,7 @@ config PPC_PMAC
select PPC_INDIRECT_PCI if PPC32
select PPC_MPC106 if PPC32
select PPC_NATIVE
+ select ZONE_DMA if PPC32
default y

config PPC_PMAC64
--
2.20.1


2019-06-13 18:52:34

by Larry Finger

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On 6/13/19 3:24 AM, Christoph Hellwig wrote:
> With the strict dma mask checking introduced with the switch to
> the generic DMA direct code common wifi chips on 32-bit powerbooks
> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> to allow them to reliably allocate dma coherent memory.
>
> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> Reported-by: Aaro Koskinen <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>

As expected, it works. The patch needs
Cc: Stable <stable*vger.kernel.org> # v5.1+

Tested-by: Larry Finger <[email protected]>
Acked-by: Larry Finger <[email protected]>

Thanks for the help, and the patience with my debugging problems with u64 variables.

Larry

2019-06-14 07:25:45

by Mathieu Malaterre

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On Thu, Jun 13, 2019 at 10:27 AM Christoph Hellwig <[email protected]> wrote:
>
> With the strict dma mask checking introduced with the switch to
> the generic DMA direct code common wifi chips on 32-bit powerbooks
> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> to allow them to reliably allocate dma coherent memory.
>
> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> Reported-by: Aaro Koskinen <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
> arch/powerpc/include/asm/page.h | 7 +++++++
> arch/powerpc/mm/mem.c | 3 ++-
> arch/powerpc/platforms/powermac/Kconfig | 1 +
> 3 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> index b8286a2013b4..0d52f57fca04 100644
> --- a/arch/powerpc/include/asm/page.h
> +++ b/arch/powerpc/include/asm/page.h
> @@ -319,6 +319,13 @@ struct vm_area_struct;
> #endif /* __ASSEMBLY__ */
> #include <asm/slice.h>
>
> +/*
> + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.

nit: would it be possible to mention explicit reference to b43-legacy.
Using b43 on my macmini g4 never showed those symptoms (using
5.2.0-rc2+)

$ dmesg | grep b43
[ 14.327189] bus: 'pci': add driver b43-pci-bridge
[ 14.345354] bus: 'pci': driver_probe_device: matched device
0001:10:12.0 with driver b43-pci-bridge
[ 14.380110] bus: 'pci': really_probe: probing driver b43-pci-bridge
with device 0001:10:12.0
[ 14.440295] b43-pci-bridge 0001:10:12.0: enabling device (0004 -> 0006)
[ 14.637223] b43-pci-bridge 0001:10:12.0: Sonics Silicon Backplane
found on PCI device 0001:10:12.0
[ 14.644858] driver: 'b43-pci-bridge': driver_bound: bound to device
'0001:10:12.0'
[ 14.743341] bus: 'pci': really_probe: bound device 0001:10:12.0 to
driver b43-pci-bridge
[ 18.724343] bus: 'bcma': add driver b43
[ 18.728635] bus: 'ssb': add driver b43
[ 18.734305] bus: 'ssb': driver_probe_device: matched device ssb0:0
with driver b43
[ 18.743155] bus: 'ssb': really_probe: probing driver b43 with device ssb0:0
[ 18.747782] b43-phy0: Broadcom 4306 WLAN found (core revision 5)
[ 18.767439] b43-phy0: Found PHY: Analog 2, Type 2 (G), Revision 2
[ 18.771759] b43-phy0: Found Radio: Manuf 0x17F, ID 0x2050, Revision
2, Version 0
[ 18.795467] driver: 'b43': driver_bound: bound to device 'ssb0:0'
[ 18.801533] bus: 'ssb': really_probe: bound device ssb0:0 to driver b43
[ 22.143084] b43-phy0: Loading firmware version 666.2 (2011-02-23 01:15:07)
[ 25.133011] b43 ssb0:0 wlan0: disabling HT as WMM/QoS is not
supported by the AP
[ 25.140221] b43 ssb0:0 wlan0: disabling VHT as WMM/QoS is not
supported by the AP


> + */
> +#ifdef CONFIG_PPC32
> +#define ARCH_ZONE_DMA_BITS 30
> +#else
> #define ARCH_ZONE_DMA_BITS 31
> +#endif
>
> #endif /* _ASM_POWERPC_PAGE_H */
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index cba29131bccc..2540d3b2588c 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -248,7 +248,8 @@ void __init paging_init(void)
> (long int)((top_of_ram - total_ram) >> 20));
>
> #ifdef CONFIG_ZONE_DMA
> - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
> + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
> + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
> #endif
> max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> #ifdef CONFIG_HIGHMEM
> diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig
> index f834a19ed772..c02d8c503b29 100644
> --- a/arch/powerpc/platforms/powermac/Kconfig
> +++ b/arch/powerpc/platforms/powermac/Kconfig
> @@ -7,6 +7,7 @@ config PPC_PMAC
> select PPC_INDIRECT_PCI if PPC32
> select PPC_MPC106 if PPC32
> select PPC_NATIVE
> + select ZONE_DMA if PPC32
> default y
>
> config PPC_PMAC64
> --
> 2.20.1
>

2019-06-14 19:04:28

by Aaro Koskinen

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

Hi,

On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote:
> With the strict dma mask checking introduced with the switch to
> the generic DMA direct code common wifi chips on 32-bit powerbooks
> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> to allow them to reliably allocate dma coherent memory.
>
> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> Reported-by: Aaro Koskinen <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>

Tested-by: Aaro Koskinen <[email protected]>

A.

> ---
> arch/powerpc/include/asm/page.h | 7 +++++++
> arch/powerpc/mm/mem.c | 3 ++-
> arch/powerpc/platforms/powermac/Kconfig | 1 +
> 3 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> index b8286a2013b4..0d52f57fca04 100644
> --- a/arch/powerpc/include/asm/page.h
> +++ b/arch/powerpc/include/asm/page.h
> @@ -319,6 +319,13 @@ struct vm_area_struct;
> #endif /* __ASSEMBLY__ */
> #include <asm/slice.h>
>
> +/*
> + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
> + */
> +#ifdef CONFIG_PPC32
> +#define ARCH_ZONE_DMA_BITS 30
> +#else
> #define ARCH_ZONE_DMA_BITS 31
> +#endif
>
> #endif /* _ASM_POWERPC_PAGE_H */
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index cba29131bccc..2540d3b2588c 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -248,7 +248,8 @@ void __init paging_init(void)
> (long int)((top_of_ram - total_ram) >> 20));
>
> #ifdef CONFIG_ZONE_DMA
> - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
> + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
> + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
> #endif
> max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> #ifdef CONFIG_HIGHMEM
> diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig
> index f834a19ed772..c02d8c503b29 100644
> --- a/arch/powerpc/platforms/powermac/Kconfig
> +++ b/arch/powerpc/platforms/powermac/Kconfig
> @@ -7,6 +7,7 @@ config PPC_PMAC
> select PPC_INDIRECT_PCI if PPC32
> select PPC_MPC106 if PPC32
> select PPC_NATIVE
> + select ZONE_DMA if PPC32
> default y
>
> config PPC_PMAC64
> --
> 2.20.1
>

2019-06-14 19:15:55

by Aaro Koskinen

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

Hi,

On Fri, Jun 14, 2019 at 09:24:16AM +0200, Mathieu Malaterre wrote:
> On Thu, Jun 13, 2019 at 10:27 AM Christoph Hellwig <[email protected]> wrote:
> > With the strict dma mask checking introduced with the switch to
> > the generic DMA direct code common wifi chips on 32-bit powerbooks
> > stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> > to allow them to reliably allocate dma coherent memory.
> >
> > Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> > Reported-by: Aaro Koskinen <[email protected]>
> > Signed-off-by: Christoph Hellwig <[email protected]>
> > ---
> > arch/powerpc/include/asm/page.h | 7 +++++++
> > arch/powerpc/mm/mem.c | 3 ++-
> > arch/powerpc/platforms/powermac/Kconfig | 1 +
> > 3 files changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> > index b8286a2013b4..0d52f57fca04 100644
> > --- a/arch/powerpc/include/asm/page.h
> > +++ b/arch/powerpc/include/asm/page.h
> > @@ -319,6 +319,13 @@ struct vm_area_struct;
> > #endif /* __ASSEMBLY__ */
> > #include <asm/slice.h>
> >
> > +/*
> > + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
>
> nit: would it be possible to mention explicit reference to b43-legacy.
> Using b43 on my macmini g4 never showed those symptoms (using
> 5.2.0-rc2+)

According to Wikipedia Mac mini G4 is limited to 1 GB RAM, so that's
why you don't see the issue.

A.

2019-06-14 20:28:32

by Larry Finger

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On 6/14/19 2:15 PM, Aaro Koskinen wrote:
> Hi,
>
> On Fri, Jun 14, 2019 at 09:24:16AM +0200, Mathieu Malaterre wrote:
>> On Thu, Jun 13, 2019 at 10:27 AM Christoph Hellwig <[email protected]> wrote:
>>> With the strict dma mask checking introduced with the switch to
>>> the generic DMA direct code common wifi chips on 32-bit powerbooks
>>> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
>>> to allow them to reliably allocate dma coherent memory.
>>>
>>> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
>>> Reported-by: Aaro Koskinen <[email protected]>
>>> Signed-off-by: Christoph Hellwig <[email protected]>
>>> ---
>>> arch/powerpc/include/asm/page.h | 7 +++++++
>>> arch/powerpc/mm/mem.c | 3 ++-
>>> arch/powerpc/platforms/powermac/Kconfig | 1 +
>>> 3 files changed, 10 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
>>> index b8286a2013b4..0d52f57fca04 100644
>>> --- a/arch/powerpc/include/asm/page.h
>>> +++ b/arch/powerpc/include/asm/page.h
>>> @@ -319,6 +319,13 @@ struct vm_area_struct;
>>> #endif /* __ASSEMBLY__ */
>>> #include <asm/slice.h>
>>>
>>> +/*
>>> + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
>>
>> nit: would it be possible to mention explicit reference to b43-legacy.
>> Using b43 on my macmini g4 never showed those symptoms (using
>> 5.2.0-rc2+)
>
> According to Wikipedia Mac mini G4 is limited to 1 GB RAM, so that's
> why you don't see the issue.

He wouldn't see it with b43. Those cards have 32-bit DMA.

Larry


2019-06-19 10:51:29

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

Any chance this could get picked up to fix the regression?

On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote:
> With the strict dma mask checking introduced with the switch to
> the generic DMA direct code common wifi chips on 32-bit powerbooks
> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> to allow them to reliably allocate dma coherent memory.
>
> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> Reported-by: Aaro Koskinen <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
> arch/powerpc/include/asm/page.h | 7 +++++++
> arch/powerpc/mm/mem.c | 3 ++-
> arch/powerpc/platforms/powermac/Kconfig | 1 +
> 3 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> index b8286a2013b4..0d52f57fca04 100644
> --- a/arch/powerpc/include/asm/page.h
> +++ b/arch/powerpc/include/asm/page.h
> @@ -319,6 +319,13 @@ struct vm_area_struct;
> #endif /* __ASSEMBLY__ */
> #include <asm/slice.h>
>
> +/*
> + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
> + */
> +#ifdef CONFIG_PPC32
> +#define ARCH_ZONE_DMA_BITS 30
> +#else
> #define ARCH_ZONE_DMA_BITS 31
> +#endif
>
> #endif /* _ASM_POWERPC_PAGE_H */
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index cba29131bccc..2540d3b2588c 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -248,7 +248,8 @@ void __init paging_init(void)
> (long int)((top_of_ram - total_ram) >> 20));
>
> #ifdef CONFIG_ZONE_DMA
> - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
> + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
> + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
> #endif
> max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> #ifdef CONFIG_HIGHMEM
> diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig
> index f834a19ed772..c02d8c503b29 100644
> --- a/arch/powerpc/platforms/powermac/Kconfig
> +++ b/arch/powerpc/platforms/powermac/Kconfig
> @@ -7,6 +7,7 @@ config PPC_PMAC
> select PPC_INDIRECT_PCI if PPC32
> select PPC_MPC106 if PPC32
> select PPC_NATIVE
> + select ZONE_DMA if PPC32
> default y
>
> config PPC_PMAC64
> --
> 2.20.1
---end quoted text---

2019-06-19 12:34:43

by Michael Ellerman

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

Christoph Hellwig <[email protected]> writes:
> Any chance this could get picked up to fix the regression?

Was hoping Ben would Ack it. He's still powermac maintainer :)

I guess he OK'ed it in the other thread, will add it to my queue.

cheers

> On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote:
>> With the strict dma mask checking introduced with the switch to
>> the generic DMA direct code common wifi chips on 32-bit powerbooks
>> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
>> to allow them to reliably allocate dma coherent memory.
>>
>> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
>> Reported-by: Aaro Koskinen <[email protected]>
>> Signed-off-by: Christoph Hellwig <[email protected]>
>> ---
>> arch/powerpc/include/asm/page.h | 7 +++++++
>> arch/powerpc/mm/mem.c | 3 ++-
>> arch/powerpc/platforms/powermac/Kconfig | 1 +
>> 3 files changed, 10 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
>> index b8286a2013b4..0d52f57fca04 100644
>> --- a/arch/powerpc/include/asm/page.h
>> +++ b/arch/powerpc/include/asm/page.h
>> @@ -319,6 +319,13 @@ struct vm_area_struct;
>> #endif /* __ASSEMBLY__ */
>> #include <asm/slice.h>
>>
>> +/*
>> + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks.
>> + */
>> +#ifdef CONFIG_PPC32
>> +#define ARCH_ZONE_DMA_BITS 30
>> +#else
>> #define ARCH_ZONE_DMA_BITS 31
>> +#endif
>>
>> #endif /* _ASM_POWERPC_PAGE_H */
>> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
>> index cba29131bccc..2540d3b2588c 100644
>> --- a/arch/powerpc/mm/mem.c
>> +++ b/arch/powerpc/mm/mem.c
>> @@ -248,7 +248,8 @@ void __init paging_init(void)
>> (long int)((top_of_ram - total_ram) >> 20));
>>
>> #ifdef CONFIG_ZONE_DMA
>> - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT);
>> + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
>> + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT);
>> #endif
>> max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
>> #ifdef CONFIG_HIGHMEM
>> diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig
>> index f834a19ed772..c02d8c503b29 100644
>> --- a/arch/powerpc/platforms/powermac/Kconfig
>> +++ b/arch/powerpc/platforms/powermac/Kconfig
>> @@ -7,6 +7,7 @@ config PPC_PMAC
>> select PPC_INDIRECT_PCI if PPC32
>> select PPC_MPC106 if PPC32
>> select PPC_NATIVE
>> + select ZONE_DMA if PPC32
>> default y
>>
>> config PPC_PMAC64
>> --
>> 2.20.1
> ---end quoted text---

2019-06-19 13:35:00

by Benjamin Herrenschmidt

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On Wed, 2019-06-19 at 22:32 +1000, Michael Ellerman wrote:
> Christoph Hellwig <[email protected]> writes:
> > Any chance this could get picked up to fix the regression?
>
> Was hoping Ben would Ack it. He's still powermac maintainer :)
>
> I guess he OK'ed it in the other thread, will add it to my queue.

Yeah ack. If I had written it myself, I would have made the DMA bits a
variable and only set it down to 30 if I see that device in the DT
early on, but I can't be bothered now, if it works, ship it :-)

Note: The patch affects all ppc32, though I don't think it will cause
any significant issue on those who don't need it.

Cheers,
Ben.

> cheers
>
> > On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote:
> > > With the strict dma mask checking introduced with the switch to
> > > the generic DMA direct code common wifi chips on 32-bit
> > > powerbooks
> > > stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> > > to allow them to reliably allocate dma coherent memory.
> > >
> > > Fixes: 65a21b71f948 ("powerpc/dma: remove
> > > dma_nommu_dma_supported")
> > > Reported-by: Aaro Koskinen <[email protected]>
> > > Signed-off-by: Christoph Hellwig <[email protected]>
> > > ---
> > > arch/powerpc/include/asm/page.h | 7 +++++++
> > > arch/powerpc/mm/mem.c | 3 ++-
> > > arch/powerpc/platforms/powermac/Kconfig | 1 +
> > > 3 files changed, 10 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/arch/powerpc/include/asm/page.h
> > > b/arch/powerpc/include/asm/page.h
> > > index b8286a2013b4..0d52f57fca04 100644
> > > --- a/arch/powerpc/include/asm/page.h
> > > +++ b/arch/powerpc/include/asm/page.h
> > > @@ -319,6 +319,13 @@ struct vm_area_struct;
> > > #endif /* __ASSEMBLY__ */
> > > #include <asm/slice.h>
> > >
> > > +/*
> > > + * Allow 30-bit DMA for very limited Broadcom wifi chips on many
> > > powerbooks.
> > > + */
> > > +#ifdef CONFIG_PPC32
> > > +#define ARCH_ZONE_DMA_BITS 30
> > > +#else
> > > #define ARCH_ZONE_DMA_BITS 31
> > > +#endif
> > >
> > > #endif /* _ASM_POWERPC_PAGE_H */
> > > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> > > index cba29131bccc..2540d3b2588c 100644
> > > --- a/arch/powerpc/mm/mem.c
> > > +++ b/arch/powerpc/mm/mem.c
> > > @@ -248,7 +248,8 @@ void __init paging_init(void)
> > > (long int)((top_of_ram - total_ram) >> 20));
> > >
> > > #ifdef CONFIG_ZONE_DMA
> > > - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL
> > > >> PAGE_SHIFT);
> > > + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
> > > + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >>
> > > PAGE_SHIFT);
> > > #endif
> > > max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> > > #ifdef CONFIG_HIGHMEM
> > > diff --git a/arch/powerpc/platforms/powermac/Kconfig
> > > b/arch/powerpc/platforms/powermac/Kconfig
> > > index f834a19ed772..c02d8c503b29 100644
> > > --- a/arch/powerpc/platforms/powermac/Kconfig
> > > +++ b/arch/powerpc/platforms/powermac/Kconfig
> > > @@ -7,6 +7,7 @@ config PPC_PMAC
> > > select PPC_INDIRECT_PCI if PPC32
> > > select PPC_MPC106 if PPC32
> > > select PPC_NATIVE
> > > + select ZONE_DMA if PPC32
> > > default y
> > >
> > > config PPC_PMAC64
> > > --
> > > 2.20.1
> >
> > ---end quoted text---

2019-06-19 14:30:55

by Mathieu Malaterre

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On Wed, Jun 19, 2019 at 4:18 PM Benjamin Herrenschmidt
<[email protected]> wrote:
>
> On Wed, 2019-06-19 at 22:32 +1000, Michael Ellerman wrote:
> > Christoph Hellwig <[email protected]> writes:
> > > Any chance this could get picked up to fix the regression?
> >
> > Was hoping Ben would Ack it. He's still powermac maintainer :)
> >
> > I guess he OK'ed it in the other thread, will add it to my queue.
>
> Yeah ack. If I had written it myself, I would have made the DMA bits a
> variable and only set it down to 30 if I see that device in the DT
> early on, but I can't be bothered now, if it works, ship it :-)
>
> Note: The patch affects all ppc32, though I don't think it will cause
> any significant issue on those who don't need it.

Thanks, that answer my earlier question.

> Cheers,
> Ben.
>
> > cheers
> >
> > > On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote:
> > > > With the strict dma mask checking introduced with the switch to
> > > > the generic DMA direct code common wifi chips on 32-bit
> > > > powerbooks
> > > > stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> > > > to allow them to reliably allocate dma coherent memory.
> > > >
> > > > Fixes: 65a21b71f948 ("powerpc/dma: remove
> > > > dma_nommu_dma_supported")
> > > > Reported-by: Aaro Koskinen <[email protected]>
> > > > Signed-off-by: Christoph Hellwig <[email protected]>
> > > > ---
> > > > arch/powerpc/include/asm/page.h | 7 +++++++
> > > > arch/powerpc/mm/mem.c | 3 ++-
> > > > arch/powerpc/platforms/powermac/Kconfig | 1 +
> > > > 3 files changed, 10 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/arch/powerpc/include/asm/page.h
> > > > b/arch/powerpc/include/asm/page.h
> > > > index b8286a2013b4..0d52f57fca04 100644
> > > > --- a/arch/powerpc/include/asm/page.h
> > > > +++ b/arch/powerpc/include/asm/page.h
> > > > @@ -319,6 +319,13 @@ struct vm_area_struct;
> > > > #endif /* __ASSEMBLY__ */
> > > > #include <asm/slice.h>
> > > >
> > > > +/*
> > > > + * Allow 30-bit DMA for very limited Broadcom wifi chips on many
> > > > powerbooks.
> > > > + */
> > > > +#ifdef CONFIG_PPC32
> > > > +#define ARCH_ZONE_DMA_BITS 30
> > > > +#else
> > > > #define ARCH_ZONE_DMA_BITS 31
> > > > +#endif
> > > >
> > > > #endif /* _ASM_POWERPC_PAGE_H */
> > > > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> > > > index cba29131bccc..2540d3b2588c 100644
> > > > --- a/arch/powerpc/mm/mem.c
> > > > +++ b/arch/powerpc/mm/mem.c
> > > > @@ -248,7 +248,8 @@ void __init paging_init(void)
> > > > (long int)((top_of_ram - total_ram) >> 20));
> > > >
> > > > #ifdef CONFIG_ZONE_DMA
> > > > - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL
> > > > >> PAGE_SHIFT);
> > > > + max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
> > > > + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >>
> > > > PAGE_SHIFT);
> > > > #endif
> > > > max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> > > > #ifdef CONFIG_HIGHMEM
> > > > diff --git a/arch/powerpc/platforms/powermac/Kconfig
> > > > b/arch/powerpc/platforms/powermac/Kconfig
> > > > index f834a19ed772..c02d8c503b29 100644
> > > > --- a/arch/powerpc/platforms/powermac/Kconfig
> > > > +++ b/arch/powerpc/platforms/powermac/Kconfig
> > > > @@ -7,6 +7,7 @@ config PPC_PMAC
> > > > select PPC_INDIRECT_PCI if PPC32
> > > > select PPC_MPC106 if PPC32
> > > > select PPC_NATIVE
> > > > + select ZONE_DMA if PPC32
> > > > default y
> > > >
> > > > config PPC_PMAC64
> > > > --
> > > > 2.20.1
> > >
> > > ---end quoted text---
>

2019-06-20 13:49:51

by Michael Ellerman

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

Benjamin Herrenschmidt <[email protected]> writes:
> On Wed, 2019-06-19 at 22:32 +1000, Michael Ellerman wrote:
>> Christoph Hellwig <[email protected]> writes:
>> > Any chance this could get picked up to fix the regression?
>>
>> Was hoping Ben would Ack it. He's still powermac maintainer :)
>>
>> I guess he OK'ed it in the other thread, will add it to my queue.
>
> Yeah ack. If I had written it myself, I would have made the DMA bits a
> variable and only set it down to 30 if I see that device in the DT
> early on, but I can't be bothered now, if it works, ship it :-)

OK, we can do that next release if someone's motivated.

> Note: The patch affects all ppc32, though I don't think it will cause
> any significant issue on those who don't need it.

Yeah. We could always hide it behind CONFIG_PPC_PMAC if it becomes a problem.

cheers

2019-06-23 10:37:24

by Michael Ellerman

[permalink] [raw]
Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac

On Thu, 2019-06-13 at 08:24:46 UTC, Christoph Hellwig wrote:
> With the strict dma mask checking introduced with the switch to
> the generic DMA direct code common wifi chips on 32-bit powerbooks
> stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds
> to allow them to reliably allocate dma coherent memory.
>
> Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported")
> Reported-by: Aaro Koskinen <[email protected]>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Tested-by: Larry Finger <[email protected]>
> Acked-by: Larry Finger <[email protected]>
> Tested-by: Aaro Koskinen <[email protected]>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/9739ab7eda459f0669ec9807e0d9be5020bab88c

cheers