The unit control address of some CXL units may be wrongly calculated
under some configuration on a EMR machine.

The current implementation only saves the unit control address of the
units from the first die, and the first unit of the rest of dies. Perf
assumed that the units from the other dies have the same offset as the
first die. So the unit control address of the rest of the units can be
calculated. However, the assumption is wrong, especially for the CXL
units.

Introduce an RB tree for each uncore type to save the unit control
address and three kinds of ID information (unit ID, PMU ID, and die ID)
for all units.
The unit ID is a physical ID of a unit.
The PMU ID is a logical ID assigned to a unit. The logical IDs start
from 0 and must be contiguous. The physical ID and the logical ID are
1:1 mapping. The units with the same physical ID in different dies share
the same PMU.
The die ID indicates which die a unit belongs to.

The RB tree can be searched by two different keys (unit ID or PMU ID +
die ID). During the RB tree setup, the unit ID is used as a key to look
up the RB tree. The perf can create/assign a proper PMU ID to the unit.
Later, after the RB tree is setup, PMU ID + die ID is used as a key to
look up the RB tree to fill the cpumask of a PMU. It's used more
frequently, so PMU ID + die ID is compared in the unit_less().
The uncore_find_unit() has to be O(N). But the RB tree setup only occurs
once during the driver load time. It should be acceptable.

Compared with the current implementation, more space is required to save
the information of all units. The extra size should be acceptable.
For example, on EMR, there are 221 units at most. For a 2-socket machine,
the extra space is ~6KB at most.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240614134631.1092359-2-kan.liang@linux.intel.com