This patch adds support for initialising & maintaining L2 caches on MIPS
systems. The L2 cache configuration may be advertised through either
coprocessor 0 or the MIPS Coherence Manager depending upon the system,
and support for both is included.
If the L2 can be bypassed then we bypass it early in boot & initialise
the L1 caches first, such that we can start making use of the L1
instruction cache as early as possible. Otherwise we initialise the L2
first such that the L1s have no opportunity to generate access to the
uninitialised L2.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Rather than probing the cache line sizes on every call of any cache
maintenance function, probe them once during boot & store the values in
the global data structure for later use. This will reduce the overhead
of the cache maintenance functions, which isn't a big deal yet but
becomes more important once L2 caches which may expose their properties
via coprocessor 2 or the CM are supported.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Commit fb64cda579 ("MIPS: Abstract cache op loops with a macro")
accidentally modified invalidate_dcache_range to operate on the L1
Icache instead of the Dcache. Fix the cache op used to operate on the
Dcache.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: fb64cda579 ("MIPS: Abstract cache op loops with a macro")
The various cache maintenance routines perform a number of loops over
cache lines. Rather than duplicate the code for performing such loops,
abstract it out into a new cache_loop macro which performs an arbitrary
number of cache ops on a range of addresses. This reduces duplication in
the existing L1 cache maintenance code & will allow for not adding
further duplication when introducing L2 cache support.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Allow L1 Icache & L1 Dcache line size to be specified separately, since
there's no architectural mandate that they be the same. The
[id]cache_line_size functions are tidied up to take advantage of the
fact that the Kconfig entries are always present to simply check them
for zero rather than needing to #ifdef on their presence.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
[removed CONFIG_SYS_CACHELINE_SIZE in include/configs/pic32mzdask.h]
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Move details of the L1 cache line sizes & total sizes into Kconfig,
defaulting to 0. A new CONFIG_SYS_CACHE_SIZE_AUTO Kconfig entry is
introduced to allow platforms to select auto-detection of cache sizes,
and it defaults to being enabled if none of the cache sizes are set by
the configuration (ie. sizes are all the default 0), and code is
adjusted to #ifdef on that rather than on the definition of the sizes
(which will always be defined even if 0).
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
This patch makes sure that the flush/invalidate_dcache_range() functions
can handle corner-case calls like this -- invalidate_dcache_range(0, 0, 0);
This call is valid and is happily produced by USB EHCI code for example.
The expected behavior of the cache function(s) in this case is that they
will do no operation, since the size is zero.
The current implementation though has a problem where such invocation will
result in a hard CPU hang. This is because under such conditions, where the
start_addr = 0 and stop = 0, the addr = 0 and aend = 0xffffffe0 . The loop
will then try to iterate over the entire address space, which in itself is
wrong. But iterating over the entire address space might also hit some odd
address which will cause bus hang. The later happens on the Atheros MIPS.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Move the more developed mips32 version of the cache maintenance
functions to a common arch/mips/lib/cache.c, in order to reduce
duplication between mips32 & mips64.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
