[PATCH] net: thunderx: add 64-bit dependency

[PATCH] net: thunderx: add 64-bit dependency

[Arnd Bergmann]

The thunderx ethernet driver fails to build on architectures
that do not have an atomic readq() and writeq() function for
64-bit PCI bus access:

drivers/net/ethernet/cavium/thunder/thunder_bgx.c: In function 'bgx_reg_read':
include/asm-generic/io.h:195:23: error: implicit declaration of function 'readq' [-Werror=implicit-function-declaration]

It seems impossible to get this driver to work on most 32-bit
hardware, so it's better to add an explicit dependency, in
order to let us keep building 'allmodconfig' kernels on
all architectures.

As the driver is meant for the internal hardware on an arm64 SoC, this
is not a problem for usability. Allowing the build on all 64-bit
architectures rather than just CONFIG_ARM64 on the other hand means that
we get the benefit of build testing on x86.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

diff --git a/drivers/net/ethernet/cavium/Kconfig b/drivers/net/ethernet/cavium/Kconfig
index 6365fb4242be..fc3d8e3ee807 100644
--- a/drivers/net/ethernet/cavium/Kconfig
+++ b/drivers/net/ethernet/cavium/Kconfig
@@ -4,7 +4,7 @@
 
 config NET_VENDOR_CAVIUM
 	tristate "Cavium ethernet drivers"
-	depends on PCI
+	depends on PCI && 64BIT
 	---help---
 	  Enable support for the Cavium ThunderX Network Interface
 	  Controller (NIC). The NIC provides the controller and DMA

Re: [PATCH] net: thunderx: add 64-bit dependency

[David Daney]

On 05/28/2015 07:00 AM, Arnd Bergmann wrote:
> The thunderx ethernet driver fails to build on architectures
> that do not have an atomic readq() and writeq() function for
> 64-bit PCI bus access:
>
> drivers/net/ethernet/cavium/thunder/thunder_bgx.c: In function 'bgx_reg_read':
> include/asm-generic/io.h:195:23: error: implicit declaration of function 'readq' [-Werror=implicit-function-declaration]
>
> It seems impossible to get this driver to work on most 32-bit
> hardware, so it's better to add an explicit dependency, in
> order to let us keep building 'allmodconfig' kernels on
> all architectures.
>
> As the driver is meant for the internal hardware on an arm64 SoC, this
> is not a problem for usability. Allowing the build on all 64-bit
> architectures rather than just CONFIG_ARM64 on the other hand means that
> we get the benefit of build testing on x86.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


Thanks for the quick fix.  I agree with your analysis...

Acked-by: David Daney <david.daney@cavium.com>

>
> diff --git a/drivers/net/ethernet/cavium/Kconfig b/drivers/net/ethernet/cavium/Kconfig
> index 6365fb4242be..fc3d8e3ee807 100644
> --- a/drivers/net/ethernet/cavium/Kconfig
> +++ b/drivers/net/ethernet/cavium/Kconfig
> @@ -4,7 +4,7 @@
>
>   config NET_VENDOR_CAVIUM
>   	tristate "Cavium ethernet drivers"
> -	depends on PCI
> +	depends on PCI && 64BIT
>   	---help---
>   	  Enable support for the Cavium ThunderX Network Interface
>   	  Controller (NIC). The NIC provides the controller and DMA
>

Re: [PATCH] net: thunderx: add 64-bit dependency

[David Miller]

From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 28 May 2015 16:00:46 +0200

> The thunderx ethernet driver fails to build on architectures
> that do not have an atomic readq() and writeq() function for
> 64-bit PCI bus access:
> 
> drivers/net/ethernet/cavium/thunder/thunder_bgx.c: In function 'bgx_reg_read':
> include/asm-generic/io.h:195:23: error: implicit declaration of function 'readq' [-Werror=implicit-function-declaration]
> 
> It seems impossible to get this driver to work on most 32-bit
> hardware, so it's better to add an explicit dependency, in
> order to let us keep building 'allmodconfig' kernels on
> all architectures.
> 
> As the driver is meant for the internal hardware on an arm64 SoC, this
> is not a problem for usability. Allowing the build on all 64-bit
> architectures rather than just CONFIG_ARM64 on the other hand means that
> we get the benefit of build testing on x86.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Applied, thanks Arnd.