Re: [PATCH-RFC 1/2 v2] tile: don't panic on iomap

Re: [PATCH-RFC 1/2 v2] tile: don't panic on iomap

[Chris Metcalf]

On 11/30/2011 4:08 AM, Michael S. Tsirkin wrote:
> I think panic on iomap is there just for debugging.
> If we return NULL instead, the generic pci_iomap will
> do the same thing as the custom one that tile currently has
> (that is, return NULL on an IO BAR)
> so tile won't need to roll its own anymore.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> Note: the other patch in the series is unchanged.
> Changes from v1:
>   - tweaked pr_info message
>
>  arch/tile/include/asm/io.h |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
> index c9ea165..d2152de 100644
> --- a/arch/tile/include/asm/io.h
> +++ b/arch/tile/include/asm/io.h
> @@ -204,7 +204,8 @@ static inline long ioport_panic(void)
>  
>  static inline void __iomem *ioport_map(unsigned long port, unsigned int len)
>  {
> -	return (void __iomem *) ioport_panic();
> +	pr_info("ioport_map: mapping IO resources is unsupported on tile.\n");
> +	return NULL;
>  }
>  
>  static inline void ioport_unmap(void __iomem *addr)

Acked-by: Chris Metcalf <cmetcalf@tilera.com>

I agree with Arnd that this isn't necessarily the best solution (build-time
failures are always preferable) but given that he's planning some more
ambitious work, this seems reasonable to me.

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com

[PATCH-RFC 1/2] tile: don't panic on iomap

[Michael S. Tsirkin]

I think panic on iomap is there just for debugging.
If we return NULL instead, the generic pci_iomap will
DTRT so we don't need to roll our own.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 arch/tile/include/asm/io.h |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
index c9ea165..be6090d 100644
--- a/arch/tile/include/asm/io.h
+++ b/arch/tile/include/asm/io.h
@@ -204,7 +204,8 @@ static inline long ioport_panic(void)
 
 static inline void __iomem *ioport_map(unsigned long port, unsigned int len)
 {
-	return (void __iomem *) ioport_panic();
+	pr_info("Trying to map an IO resource - it does not exit on tile.\n");
+	return NULL;
 }
 
 static inline void ioport_unmap(void __iomem *addr)
-- 
1.7.5.53.gc233e

[PATCH-RFC 1/2 v2] tile: don't panic on iomap

[Michael S. Tsirkin]

I think panic on iomap is there just for debugging.
If we return NULL instead, the generic pci_iomap will
do the same thing as the custom one that tile currently has
(that is, return NULL on an IO BAR)
so tile won't need to roll its own anymore.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

Note: the other patch in the series is unchanged.
Changes from v1:
  - tweaked pr_info message

 arch/tile/include/asm/io.h |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/tile/include/asm/io.h b/arch/tile/include/asm/io.h
index c9ea165..d2152de 100644
--- a/arch/tile/include/asm/io.h
+++ b/arch/tile/include/asm/io.h
@@ -204,7 +204,8 @@ static inline long ioport_panic(void)
 
 static inline void __iomem *ioport_map(unsigned long port, unsigned int len)
 {
-	return (void __iomem *) ioport_panic();
+	pr_info("ioport_map: mapping IO resources is unsupported on tile.\n");
+	return NULL;
 }
 
 static inline void ioport_unmap(void __iomem *addr)
-- 
1.7.5.53.gc233e