user/sven/linux.git/drivers/fsi, branch v5.10.42

fsi: Aspeed: Add mutex to protect HW access

2020-12-30T10:53:46Z

[ Upstream commit dfd7f2c1c532efaeff6084970bb60ec2f2e44191 ] There is nothing to prevent multiple commands being executed simultaneously. Add a mutex to prevent this. Fixes: 606397d67f41 ("fsi: Add ast2600 master driver") Reviewed-by: Joel Stanley Reviewed-by: Milton Miller Signed-off-by: Eddie James Signed-off-by: Joel Stanley Link: https://lore.kernel.org/r/20201120004929.185239-1-joel@jms.id.au Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

fsi: aspeed: Support CFAM reset GPIO

2020-09-10T02:56:43Z

Systems have a line for restting the remote CFAM. This is not part of the FSI master, but is associated with it, so it makes sense to include it in the master driver. This exposes a sysfs interface to reset the cfam, abstracting away the direction and polarity of the GPIO, as well as the timing of the reset pulse. Userspace will be blocked until the reset pulse is finished. The reset is hard coded to be in the range of (900, 1000) us. It was observed with a scope to regularly be just over 1ms. If the device tree property is not preset the driver will silently continue. Reviewed-by: Andrew Jeffery Link: https://lore.kernel.org/r/20200728025527.174503-6-joel@jms.id.au Signed-off-by: Joel Stanley

fsi: aspeed: Add module param for bus divisor

2020-09-10T02:53:19Z

For testing and hardware debugging a user may wish to override the divisor at runtime. By setting fsi_master_aspeed.bus_div=N, the divisor will be set to N, if 0 < N <= 0x3ff. This is a module parameter and not a device tree option as it will only need to be set when testing or debugging. Reviewed-by: Eddie James Link: https://lore.kernel.org/r/20200728025527.174503-5-joel@jms.id.au Signed-off-by: Joel Stanley

fsi: aspeed: Run the bus at maximum speed

2020-09-10T02:53:17Z

Testing of Tacoma has shown that the ASPEED master can be run at maximum speed. The exception is when wired externally with a cable, in which case we use a divisor of two to ensure reliable operation. Reviewed-by: Eddie James Link: https://lore.kernel.org/r/20200728025527.174503-4-joel@jms.id.au Signed-off-by: Joel Stanley

fsi: aspeed: Support cabled FSI

2020-09-10T02:53:14Z

Some FSI capable systems have internal FSI signals, and some have external cabled FSI. Software can detect which machine this is by reading a jumper GPIO, and also control which pins the signals are routed to through a mux GPIO. This attempts to find the GPIOs at probe time. If they are not present in the device tree the driver will not error and continue as before. The mux GPIO is owned by the FSI driver to ensure it is not modified at runtime. The routing jumper obtained as non-exclusive to allow other software to inspect it's state. Reviewed-by: Andrew Jeffery Link: https://lore.kernel.org/r/20200728025527.174503-3-joel@jms.id.au Signed-off-by: Joel Stanley

fsi: scom: Constify scom_ids

2020-09-10T02:52:51Z

The only usage of scom_ids is to assign its address to the id_table field in the fsi_driver struct, which is a const pointer, so make it const to allow the compiler to put it in read-only memory Signed-off-by: Rikard Falkeborn Signed-off-by: Joel Stanley

fsi: sbefifo: Constify sbefifo_ids

2020-09-10T02:52:50Z

The only usage of sbefifo_ids is to assign its address to the id_table field in the fsi_driver struct, which is a const pointer, so make it const to allow the compiler to put it in read-only memory Signed-off-by: Rikard Falkeborn Signed-off-by: Joel Stanley

fsi: master: Constify hub_master_ids

2020-09-10T02:52:50Z

The only usage of hub_master_ids is to assign its address to the id_table field in the fsi_driver struct, which is a const pointer, so make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn Signed-off-by: Joel Stanley

fsi: master: Remove link enable read-back

2020-09-10T02:52:49Z

Both the Aspeed and hub masters read back the link enable register after enabling the link, but this is unnecessary, so remove it. Signed-off-by: Eddie James Signed-off-by: Joel Stanley

fsi: core: Set slave local bus ownership during init

2020-09-10T02:52:49Z

The driver ought to claim local bus ownership of the slave it's communicating with. This is for multi-master setups. The slave (in theory) will deny access to masters who try to access the CFAM address space but who don't "own" the bus. As driver doesn't seem to perform any other teardown there is no need to "un-claim" ownership at teardown. Also I'm not aware of any multi-master setup using this driver so it shouldn't actually matter. Also, the hardware doesn't seem to enforce this despite being required in the specification... Signed-off-by: Eddie James Signed-off-by: Joel Stanley