fpga: dfl: more kernel-doc corrections

Fix more kernel-doc warnings in drivers/fpga/:

$ ./scripts/kernel-doc -none drivers/fpga/*
drivers/fpga/dfl-afu.h:61: warning: expecting prototype for struct fpga_afu_dma_region. Prototype was for struct dfl_afu_dma_region instead
drivers/fpga/dfl-afu-region.c:52: warning: Function parameter or member 'pdata' not described in 'afu_mmio_region_add'
drivers/fpga/dfl-fme-perf.c:161: warning: Function parameter or member 'node' not described in 'fme_perf_priv'
drivers/fpga/dfl-fme-pr.h:70: warning: expecting prototype for struct dfl_fme_bridge_pdata. Prototype was for struct dfl_fme_br_pdata instead
drivers/fpga/dfl.h:256: warning: Function parameter or member 'revision' not described in 'dfl_feature'

Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230114155444.794712-1-yilun.xu@intel.com

fpga: dfl: fme: Fix cpu hotplug issue in performance reporting

The performance reporting driver added cpu hotplug
feature but it didn't add pmu migration call in cpu
offline function.
This can create an issue incase the current designated
cpu being used to collect fme pmu data got offline,
as based on current code we are not migrating fme pmu to
new target cpu. Because of that perf will still try to
fetch data from that offline cpu and hence we will not
get counter data.

Patch fixed this issue by adding pmu_migrate_context call
in fme_perf_offline_cpu function.

Fixes: 724142f8c42a ("fpga: dfl: fme: add performance reporting support")
Cc: stable@vger.kernel.org
Tested-by: Xu Yilun <yilun.xu@intel.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>

fpga: dfl: fme: Constify static attribute_group structs

The only usage of these is to put their addresses in arrays of pointers
to const attribute_groups. Make them const to allow the compiler to put
them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>

fpga: dfl: change data type of feature id to u16

The feature id is stored in a 12 bit field in DFH. So a u16 variable is
enough for feature id.

This patch changes all feature id related places to fit u16.

Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Acked-by: Wu Hao <hao.wu@intel.com>
Signed-off-by: Moritz Fischer <mdf@kernel.org>

fpga: dfl: fme: add performance reporting support

This patch adds support for performance reporting private feature
for FPGA Management Engine (FME). Now it supports several different
performance counters, including 'basic', 'cache', 'fabric', 'vtd'
and 'vtd_sip'. It allows user to use standard linux tools to access
these performance counters.

e.g. List all events by "perf list"

perf list | grep fme

dfl_fme0/cache_read_hit/ [Kernel PMU event]
dfl_fme0/cache_read_miss/ [Kernel PMU event]
...

dfl_fme0/fab_mmio_read/ [Kernel PMU event]
dfl_fme0/fab_mmio_write/ [Kernel PMU event]
...

dfl_fme0/fab_port_mmio_read,portid=?/ [Kernel PMU event]
dfl_fme0/fab_port_mmio_write,portid=?/ [Kernel PMU event]
...

dfl_fme0/vtd_port_devtlb_1g_fill,portid=?/ [Kernel PMU event]
dfl_fme0/vtd_port_devtlb_2m_fill,portid=?/ [Kernel PMU event]
...

dfl_fme0/vtd_sip_iotlb_1g_hit/ [Kernel PMU event]
dfl_fme0/vtd_sip_iotlb_1g_miss/ [Kernel PMU event]
...

dfl_fme0/clock [Kernel PMU event]
...

e.g. check increased counter value after run one application using
"perf stat" command.

perf stat -e dfl_fme0/fab_mmio_read/,dfl_fme0/fab_mmio_write/ ./test

Performance counter stats for './test':

1 dfl_fme0/fab_mmio_read/
2 dfl_fme0/fab_mmio_write/

1.009496520 seconds time elapsed

Please note that fabric counters support both fab_* and fab_port_*, but
actually they are sharing one set of performance counters in hardware.
If user wants to monitor overall data events on fab_* then fab_port_*
can't be supported at the same time, see example below:

perf stat -e dfl_fme0/fab_mmio_read/,dfl_fme0/fab_port_mmio_write,portid=0/

Performance counter stats for 'system wide':

0 dfl_fme0/fab_mmio_read/
<not supported> dfl_fme0/fab_port_mmio_write,portid=0/

2.141064085 seconds time elapsed

Signed-off-by: Luwei Kang <luwei.kang@intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Wu Hao <hao.wu@intel.com>
Link: https://lore.kernel.org/r/1587949583-12058-3-git-send-email-hao.wu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>