On 8/5/2016 06:00 AM, Mark Rutland wrote: > On Thu, Aug 04, 2016 at 05:11:10PM -0400, Neil Leeder wrote: >> L2 registers are accessed using a select register and data >> register pair. To prevent multiple concurrent writes to the >> select register by independent drivers, the write to the >> select register and the associated access of the data register >> are protected with a lock. All drivers accessing the L2 >> registers use the set and get functions provided by >> l2-accessors to ensure correct reads and writes to L2 registers. > > As of this series, this is only used by the PMU driver. Which other > drivers do you plan to use this for? > > If there's nothing else planned at the moment, it would be nicer to fold > these into the PMU driver. > I see a couple of other drivers on codeaurora.org using it: the Error Reporting (ERP) driver and an adaptive clock generator. I'd guess they'll be submitted to LKML but they're not mine so I don't know when. As the purpose of this is to be the common interface for multiple drivers to stop them walking over each other, I think it makes sense to keep it separate. > [...] > >> +config QCOM_L2_ACCESSORS >> + bool "Qualcomm Technologies L2-cache accessors" >> + depends on ARCH_QCOM && ARM64 >> + help >> + Say y here to enable support for the Qualcomm Technologies >> + L2 accessors. >> + Provides support for accessing registers in the L2 cache >> + for Qualcomm Technologies chips. > > Which chips have this? Qualcomm Technologies ARM64 chips, so currently QDF24xx family and anything Kryo based. I'd assume any future chip families as well. Given the 'depends on' line, I wasn't sure there was any benefit to essentially duplicating that in the help text. > > Have drivers select this as necessary. There's no reason for this to be > used-selectable given this is trivial common infrastructure. OK, I'll fix that > > [...] > >> +#include <linux/spinlock.h> >> +#include <linux/export.h> >> +#include <linux/soc/qcom/l2-accessors.h> >> +#include <asm/cputype.h> >> +#include <asm/sysreg.h> > > Nit: please sort these alphabetically. OK > > [...] > >> +EXPORT_SYMBOL(set_l2_indirect_reg); > > The PMU driver isn't a module, so this doesn't need to be exported. > Until there's a modular user, please get rid of EXPORT_SYMBOL. > >> +EXPORT_SYMBOL(get_l2_indirect_reg); > > Likewise. OK to both of these. > > Thanks, > Mark. > Thank you for the comments. Neil -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
