The CCSIDR_EL1.{NumSets,Associativity,LineSize} fields are only for use
in conjunction with set/way cache maintenance and are not guaranteed to
represent the actual microarchitectural features of a design.
The architecture explicitly states:
| You cannot make any inference about the actual sizes of caches based
| on these parameters.
Furthermore, CCSIDR_EL1.{WT,WB,RA,WA} have been removed retrospectively
from ARMv8 and are now considered to be UNKNOWN.
Since the kernel doesn't make use of set/way cache maintenance and it is
not possible for userspace to execute these instructions, we have no
need for the CCSIDR information in the kernel.
This patch removes the accessors, along with the related portions of the
cacheinfo support, which should instead be reintroduced when firmware has
a mechanism to provide us with reliable information.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The cache hierarchy can be identified through Cache Level ID(CLIDR)
architected system register. However in some cases it will provide
only the number of cache levels that are integrated into the processor
itself. In other words, it can't provide any information about the
caches that are external and/or transparent.
Some platforms require to export the information about all such external
caches to the userspace applications via the sysfs interface.
This patch adds support to override the cache levels using device tree
to take such external non-architected caches into account.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Tested-by: Tan Xiaojun <tanxiaojun@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
A while back we added {read,write}_sysreg accessors to handle accesses
to system registers, without the usual boilerplate asm volatile,
temporary variable, etc.
This patch makes use of these across arm64 to make code shorter and
clearer. For sequences with a trailing ISB, the existing isb() macro is
also used so that asm blocks can be removed entirely.
A few uses of inline assembly for msr/mrs are left as-is. Those
manipulating sp_el0 for the current thread_info value have special
clobber requiremends.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch adds support for cacheinfo on ARM64.
On ARMv8, the cache hierarchy can be identified through Cache Level ID
(CLIDR) register while the cache geometry is provided by Cache Size ID
(CCSIDR) register.
Since the architecture doesn't provide any way of detecting the cpus
sharing particular cache, device tree is used for the same purpose.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
