firmware: xilinx: Switch Michal Simek's email to new one

@xilinx.com is still working but better to switch to new amd.com after
AMD/Xilinx acquisition.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/36d119221aa12369c601cd37160306aeb84fc973.1684244767.git.michal.simek@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: xilinx: Remove eemi ops for query_data

Use direct function call for query_data instead of using eemi ops.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-4-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: xilinx: Remove eemi ops for get_api_version

Use direct function calls instead of using eemi ops. So remove
eemi ops for get_api_version and use direct function call.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jolly.shah@xilinx.com>
Link: https://lore.kernel.org/r/1587761887-4279-2-git-send-email-jolly.shah@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

firmware: xilinx: make firmware_debugfs_root static

Fix the following sparse warning:

drivers/firmware/xilinx/zynqmp-debug.c:38:15: warning: symbol
'firmware_debugfs_root' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200415084311.24857-1-yanaijie@huawei.com
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

drivers: Defer probe if firmware is not ready

Driver needs ZynqMP firmware interface to call EEMI
APIs. In case firmware is not ready, dependent drivers
should wait until the firmware is ready.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

firmware: xilinx: fix debugfs write handler

- Userspace wants to write a string with `len` bytes, not counting the
terminating NULL, so we should allocate `len+1` bytes. It looks like the
current code relied on having a nullbyte directly behind `kern_buff`,
which happens to work reliably as long as `len` isn't one of the kmalloc
size classes.
- strncpy_from_user() is completely wrong here; userspace is giving us a
(not necessarily null-terminated) buffer and its length.
strncpy_from_user() is for cases in which we don't know the length.
- Don't let broken userspace allocate arbitrarily big kmalloc allocations.

Just use memdup_user_nul(), which is designed precisely for things like
this.

Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Jolly Shah <jolly.shah@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

firmware: xilinx: Add debugfs for query data API

Add debugfs file to query platform specific data from firmware
using debugfs interface.

Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

firmware: xilinx: Add debugfs interface

Firmware-debug provides debugfs interface to all APIs.
Debugfs can be used to call firmware APIs with required
parameters.

Usage:
* Calling firmware API through debugfs:
# echo "<api-name> <arg1> .. <argn>" > /sys/.../zynqmp-firmware/pm

* Read output of last called firmware API:
# cat /sys/.../zynqmp-firmware/pm

Refer ug1200 for more information on these APIs:
* https://www.xilinx.com/support/documentation/user_guides/ug1200-eemi-api.pdf

Add basic debugfs file to get API version.

Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>