[U-Boot] [PATCH 2/2] arm: socfpga: enable data/inst prefetch and shared override in the L2

[Marek Vasut]

On Thursday, October 15, 2015 at 08:18:43 PM, Dinh Nguyen wrote:
> On Thu, Oct 15, 2015 at 1:08 PM, Marek Vasut <marex at denx.de> wrote:
> > On Thursday, October 15, 2015 at 05:04:38 PM, Dinh Nguyen wrote:
> > 
> > Hi!
> > 
> >> >>> diff --git a/arch/arm/include/asm/pl310.h
> >> >>> b/arch/arm/include/asm/pl310.h index 18b90b7..7a11405 100644
> >> >>> --- a/arch/arm/include/asm/pl310.h
> >> >>> +++ b/arch/arm/include/asm/pl310.h
> >> >>> @@ -17,6 +17,8 @@
> >> >>> 
> >> >>>  #define L2X0_CTRL_EN                             1
> >> >>>  
> >> >>>  #define PL310_SHARED_ATT_OVERRIDE_ENABLE         (1 << 22)
> >> >>> 
> >> >>> +#define PL310_AUX_CTRL_DATA_PREFETCH_MASK        (1 << 28)
> >> >>> +#define PL310_AUX_CTRL_INST_PREFETCH_MASK        (1 << 29)
> >> >> 
> >> >> These would be
> >> >> 
> >> >> arch/arm/include/asm/hardware/cache-l2x0.h:#define
> >> >> L310_PREFETCH_CTRL_DATA_PREFETCH     BIT(28)
> >> >> arch/arm/include/asm/hardware/cache-l2x0.h:#define
> >> >> L310_PREFETCH_CTRL_INSTR_PREFETCH    BIT(29)
> >> >> 
> >> >> ...in kernel. So maybe staying with L310_ prefix makes sense?
> >> >> Otherwise it looks ok.
> >> > 
> >> > Why is it L... in one and PL... in the other one ? What does the "PL"
> >> > prefix stand for anyway ?
> >> 
> >> As Pavel pointed out, it should be L310_x as this is how the Linux
> >> kernel is defining it. It's my mistake in the previous patch to change
> >> the define to PL310.
> >> 
> >> I'll respin this patch with L310_PREFETCH_CTRL_DATA_PREFETCH and
> >> L310_PREFETCH_CTRL_INSTR_PREFETCH.
> > 
> > Well that didn't answer either of my questions ;-)
> 
> It should have been just 'L" and not "PL" at all.

Why ? What does that "PL" stand for and why can we omit the P ?

I don't mean to grind you, don't get me wrong, I'm gonna pick the V2 tomorrow,
I just want to understand why it's enough to omit the P .

Best regards,
Marek Vasut