mem: Move ruby protocols into a directory called ruby_protocol.

Now that the gem5 protocols are split out, it would be nice to put them
in their own protocol directory. It's also confusing to have files
called *_protocol which are not in the protocol directory.

Change-Id: I7475ee111630050a2421816dfd290921baab9f71
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20230
Reviewed-by: Gabe Black <gabeblack@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

gpu-compute: AMD's baseline GPU model

misc: Remove redundant compiler-specific defines

This patch moves away from using M5_ATTR_OVERRIDE and the m5::hashmap
(and similar) abstractions, as these are no longer needed with gcc 4.7
and clang 3.1 as minimum compiler versions.

ruby: call setMRU from L1 controllers, not from sequencer
Currently the sequencer calls the function setMRU that updates the replacement
policy structures with the first level caches. While functionally this is
correct, the problem is that this requires calling findTagInSet() which is an
expensive function. This patch removes the calls to setMRU from the sequencer.
All controllers should now update the replacement policy on their own.

The set and the way index for a given cache entry can be found within the
AbstractCacheEntry structure. Use these indicies to update the replacement
policy structures.

ruby: eliminate type uint64 and int64
These types are being replaced with uint64_t and int64_t.

ruby: handle llsc accesses through CacheEntry, not CacheMemory

The sequencer takes care of llsc accesses by calling upon functions
from the CacheMemory. This is unnecessary once the required CacheEntry object
is available. Thus some of the calls to findTagInSet() are avoided.

ruby: reverts to changeset: bf82f1f7b040

ruby: cache memory: drop {try,test}CacheAccess functions

ruby: call setMRU from L1 controllers, not from sequencer
Currently the sequencer calls the function setMRU that updates the replacement
policy structures with the first level caches. While functionally this is
correct, the problem is that this requires calling findTagInSet() which is an
expensive function. This patch removes the calls to setMRU from the sequencer.
All controllers should now update the replacement policy on their own.

The set and the way index for a given cache entry can be found within the
AbstractCacheEntry structure. Use these indicies to update the replacement
policy structures.

ruby: eliminate type uint64 and int64

These types are being replaced with uint64_t and int64_t.

ruby: handle llsc accesses through CacheEntry, not CacheMemory

The sequencer takes care of llsc accesses by calling upon functions
from the CacheMemory. This is unnecessary once the required CacheEntry object
is available. Thus some of the calls to findTagInSet() are avoided.

ruby: replace Address by Addr
This patch eliminates the type Address defined by the ruby memory system.
This memory system would now use the type Addr that is in use by the
rest of the system.

ruby: Remove the RubyCache/CacheMemory latency

The RubyCache (CacheMemory) latency parameter is only used for top-level caches
instantiated for Ruby coherence protocols. However, the top-level cache hit
latency is assessed by the Sequencer as accesses flow through to the cache
hierarchy. Further, protocol state machines should be enforcing these cache hit
latencies, but RubyCaches do not expose their latency to any existng state
machines through the SLICC/C++ interface. Thus, the RubyCache latency parameter
is superfluous for all caches. This is confusing for users.

As a step toward pushing L0/L1 cache hit latency into the top-level cache
controllers, move their latencies out of the RubyCache declarations and over to
their Sequencers. Eventually, these Sequencer parameters should be exposed as
parameters to the top-level cache controllers, which should assess the latency.
NOTE: Assessing these latencies in the cache controllers will require modifying
each to eliminate instantaneous Ruby hit callbacks in transitions that finish
accesses, which is likely a large undertaking.

ruby: expose access permission to replacement policies

This patch adds support that allows the replacement policy to identify each
cache block's access permission. This information can be useful when making
replacement decisions.

ruby: fix deadlock bug in banked array resource checks

The Ruby banked array resource checks (initiated from SLICC) did a check and
allocate at the same time. If a transition needs more than one resource, then
it might check/allocate resource #1, then fail to get resource #2. Another
transition might then try to get the same resources, but in reverse order.
Deadlock.

This patch separates resource checking and resource reservation into two
steps to avoid deadlock.

ruby: allocate a block in CacheMemory without updating LRU state

ruby: speed up function used for cache walks

This patch adds a few helpful functions that allow .sm files to directly
invalidate all cache blocks using a trigger queue rather than rely on each
individual cache block to be invalidated via requests from the mandatory
queue.

ruby: initialize replacement policies with their own simobjs

this is in preparation for other replacement policies that take additional
parameters.

ruby: give access to cache tag/data latencies from SLICC

This patch exposes the tag and data array latencies to the SLICC state machines
so that it can be used to determine the correct enqueue latency for response
messages.

ruby: structures: coorect #ifndef macros in header files

ruby: remove typedef of Index as int64
The Index type defined as typedef int64 does not really provide any help
since in most places we use primitive types instead of Index. Also, the name
Index is very generic that it does not merit being used as a typename.

ruby: move files from ruby/system to ruby/structures

The directory ruby/system is crowded and unorganized. Hence, the files the
hold actual physical structures, are being moved to the directory
ruby/structures. This includes Cache Memory, Directory Memory,
Memory Controller, Wire Buffer, TBE Table, Perfect Cache Memory, Timer Table,
Bank Array.

The directory ruby/systems has the glue code that holds these structures
together.