On 2023-04-05 at 11:01:52 +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. > > 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> > --- > drivers/fpga/intel-m10-bmc-sec-update.c | 17 +++++-- > drivers/mfd/intel-m10-bmc-core.c | 63 ++++++++++++++++++++++++- > drivers/mfd/intel-m10-bmc-pmci.c | 4 ++ > drivers/mfd/intel-m10-bmc-spi.c | 14 ++++++ > include/linux/mfd/intel-m10-bmc.h | 27 +++++++++++ > 5 files changed, 120 insertions(+), 5 deletions(-) > [...] > > +void m10bmc_fw_state_set(struct intel_m10bmc *m10bmc, enum m10bmc_fw_state new_state) > +{ > + down_write(&m10bmc->bmcfw_lock); > + m10bmc->bmcfw_state = new_state; > + up_write(&m10bmc->bmcfw_lock); Could we also skip this if no handshake is possible like for PMCI? Thanks, Yilun