[PATCH 2/5] drivers/bus: Split Arm CCI driver

Will Deacon will.deacon at arm.com
Wed Feb 14 03:51:19 PST 2018


On Wed, Feb 07, 2018 at 01:07:53PM +0000, Robin Murphy wrote:
> Hi Punit,
> 
> On 07/02/18 12:22, Punit Agrawal wrote:
> [...]
> >>-static void __iomem *cci_ctrl_base;
> >>+void __iomem *cci_ctrl_base __ro_after_init;
> >
> >Initially I wondered if cci_ctrl_base gets used in the pmu driver before
> >it's initialised. But as it gets set in early_initcall() that looks to
> >be fine.
> 
> In fact it's even more robust than initcall ordering, since the PMU device
> will only be created at all via cci_platform_probe(), thus cci_init() is
> guaranteed to have run successfully before the PMU driver probe can ever
> touch anything.

Could you hijack the platform data at this point by passing an of_dev_auxdata
to of_platform_populate and then use that to pass the __iomem address to the
PMU driver?

Will



More information about the linux-arm-kernel mailing list