On 14/06/16 17:49, Russell King - ARM Linux wrote:

On Tue, Jun 14, 2016 at 05:44:26PM +0100, Sudeep Holla wrote:

quoted

Even with higher latency if the platform is unusable, I agree to remove.
If you think it's usable with the updated latency(<2 2 1>) then we can
update it.

The kernels I'm booting have that updated latency.  It used to improve
things, but for most of this year, it fails most boot attempts.  Out
of the last 21 boot attempts, all 21 attempts failed with the above
latency value.

Thanks, I do see that, it's unreliable with higher latencies too. If I
increase them, it seem to work, but again as the size of the image
increases the behavior changes.

So, apart from increasing the latency or removing the DT completely, I
was thinking of 3rd option of disabling L2CC on Vexpress CA9 coretile.
Let me know if that's acceptable. I thought it's reasonable as we
still can the platform support without L2CC enabled.

Regards,
Sudeep


-->8

diff --git i/arch/arm/boot/dts/vexpress-v2p-ca9.dts 

w/arch/arm/boot/dts/vexpress-v2p-ca9.dts
index b608a03ee02f..9742448b4e85 100644

--- i/arch/arm/boot/dts/vexpress-v2p-ca9.dts
+++ w/arch/arm/boot/dts/vexpress-v2p-ca9.dts

@@ -174,6 +174,7 @@
                 cache-level = <2>;
                 arm,data-latency = <1 1 1>;
                 arm,tag-latency = <1 1 1>;
+               status = "disabled";
         };

         pmu {

diff --git i/arch/arm/mm/cache-l2x0.c w/arch/arm/mm/cache-l2x0.c
index c61996c256cc..569fb1f0994b 100644
--- i/arch/arm/mm/cache-l2x0.c
+++ w/arch/arm/mm/cache-l2x0.c

@@ -1750,6 +1750,9 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
         if (!np)
                 return -ENODEV;

+       if (!of_device_is_available(np))
+               return -ENODEV;
+
         if (of_address_to_resource(np, 0, &res))
                 return -ENODEV;