Re: [PATCH v3 4/4] mfd: intel-m10-bmc: Manage access to MAX 10 fw handshake registers

From: Xu Yilun
Date: Thu Apr 20 2023 - 21:52:11 EST


On 2023-04-20 at 12:13:24 +0100, Lee Jones wrote:
> On Fri, 21 Apr 2023, Xu Yilun wrote:
>
> > On 2023-04-17 at 12:26:53 +0300, Ilpo Järvinen wrote:
> > > On some MAX 10 cards, the BMC firmware is not available to service
> > > handshake registers during secure update erase and write phases at
> > > normal speeds. This problem affects at least hwmon driver. When the MAX
> > > 10 hwmon driver tries to read the sensor values during a secure update,
> > > the reads are slowed down (e.g., reading all D5005 sensors takes ~24s
> > > which is magnitudes worse than the normal <0.02s).
> > >
> > > Manage access to the handshake registers using a rw semaphore and a FW
> > > state variable to prevent accesses during those secure update phases
> > > and return -EBUSY instead.
> > >
> > > If handshake_sys_reg_nranges == 0, don't update bwcfw_state as it is not
> > > used. This avoids the locking cost.
> > >
> > > Co-developed-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> > > Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
> > > Co-developed-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> > > Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
> >
> > Reviewed-by: Xu Yilun <yilun.xu@xxxxxxxxx>
> >
> > Hi Lee:
> >
> > Could the fpga part also been applied to mfd tree when everyone is good?
>
> Yes, with an Acked-by it can.

Acked-by: Xu Yilun <yilun.xu@xxxxxxxxx>

>
> --
> Lee Jones [李琼斯]