[PATCH] Provide a stub ioperm implementation for ARMv5 and later

[Aurelien Jarno]

On 2015-12-12 20:26, Phil Blundell wrote:
> On Sat, 2015-12-12 at 19:59 +0100, Aurelien Jarno wrote:
> > The ioperm, iopl, in{b,w,l} and out{b,w,l} functions only make sense
> > on ARMv4.
> 
> This statement isn't strictly true.  There is no inherent relationship
> between the architecture level and the availability or not of the
> port-mapped I/O functions.  And, in fact, a quick survey suggests that
> there is at least one counterexample in the kernel: CONFIG_ARCH_VIPER is
> a PXA25x board (hence ARMv5TE) and seems to include ISA.  So, I am not
> all that keen on this patch. 

This patch was actually in answer to the remark from Arnd Bergmann on
the other ioperm patch. I admit I should have checked more in details
about that.

> If you wanted to clean up the ioperm code a bit then it would probably
> make sense to remove all the legacy stuff that grubs around
> in /proc/cpuinfo and /etc/arm_systype to figure out what sort of machine
> it's on, since this is only needed for kernels that are so old as to
> lack the CTL_BUS_ISA sysctls.

OK, I'll have a look at that someday.

Aurelien

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                 http://www.aurel32.net