Re: [PATCH] irqchip/gic-v3: do not access GICR_WAKER if its secured register.

From: Srinivas Kandagatla
Date: Tue Jun 12 2018 - 11:51:48 EST

On 12/06/18 16:24, Sudeep Holla wrote:
On Tue, Jun 12, 2018 at 3:55 PM, Srinivas Kandagatla
<srinivas.kandagatla@xxxxxxxxxx> wrote:
GICR_WAKER can be a secured register, check this before accessing it
as its done in power management code.

Without this patch Qualcomm DB820c board crashes.

Are you sure this is the one causing the crash ?

Yep, am 100% sure its the write in gic_enable_redist(). Very first zero write to GICR_WAKER is the one which is crashing my system.

If I add return before writing then I can boot my system fine.

Not sure why writes are not ignored?

Also why does other parts of the code have checks while accessing this register?


As per GIC specification:
"When GICD_CTLR.DS==1, this register is always accessible.
When GICD_CTLR.DS==0, this is a Secure register. This register is RAZ/WI
to Non-secure accesses."