There are three independent sets of changes:
- Sai Prakash Ranjan adds tracing support to the asm-generic
version of the MMIO accessors, which is intended to help
understand problems with device drivers and has been part
of Qualcomm's vendor kernels for many years.
- A patch from Sebastian Siewior to rework the handling of
IRQ stacks in softirqs across architectures, which is
needed for enabling PREEMPT_RT.
- The last patch to remove the CONFIG_VIRT_TO_BUS option and
some of the code behind that, after the last users of this
old interface made it in through the netdev, scsi, media and
staging trees.
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Merge tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull asm-generic updates from Arnd Bergmann:
"There are three independent sets of changes:
- Sai Prakash Ranjan adds tracing support to the asm-generic version
of the MMIO accessors, which is intended to help understand
problems with device drivers and has been part of Qualcomm's vendor
kernels for many years
- A patch from Sebastian Siewior to rework the handling of IRQ stacks
in softirqs across architectures, which is needed for enabling
PREEMPT_RT
- The last patch to remove the CONFIG_VIRT_TO_BUS option and some of
the code behind that, after the last users of this old interface
made it in through the netdev, scsi, media and staging trees"
* tag 'asm-generic-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
uapi: asm-generic: fcntl: Fix typo 'the the' in comment
arch/*/: remove CONFIG_VIRT_TO_BUS
soc: qcom: geni: Disable MMIO tracing for GENI SE
serial: qcom_geni_serial: Disable MMIO tracing for geni serial
asm-generic/io: Add logging support for MMIO accessors
KVM: arm64: Add a flag to disable MMIO trace for nVHE KVM
lib: Add register read/write tracing support
drm/meson: Fix overflow implicit truncation warnings
irqchip/tegra: Fix overflow implicit truncation warnings
coresight: etm4x: Use asm-generic IO memory barriers
arm64: io: Use asm-generic high level MMIO accessors
arch/*: Disable softirq stacks on PREEMPT_RT.
When the following configs are enabled:
* CORESIGHT
* CORESIGHT_SOURCE_ETM4X
* UBSAN
* UBSAN_TRAP
Clang fails assemble the kernel with the error:
<instantiation>:1:7: error: expected constant expression in '.inst' directive
.inst (0xd5200000|((((2) << 19) | ((1) << 16) | (((((((((((0x160 + (i * 4))))) >> 2))) >> 7) & 0x7)) << 12) | ((((((((((0x160 + (i * 4))))) >> 2))) & 0xf)) << 8) | (((((((((((0x160 + (i * 4))))) >> 2))) >> 4) & 0x7)) << 5)))|(.L__reg_num_x8))
^
drivers/hwtracing/coresight/coresight-etm4x-core.c:702:4: note: while in
macro instantiation
etm4x_relaxed_read32(csa, TRCCNTVRn(i));
^
drivers/hwtracing/coresight/coresight-etm4x.h:403:4: note: expanded from
macro 'etm4x_relaxed_read32'
read_etm4x_sysreg_offset((offset), false)))
^
drivers/hwtracing/coresight/coresight-etm4x.h:383:12: note: expanded
from macro 'read_etm4x_sysreg_offset'
__val = read_etm4x_sysreg_const_offset((offset)); \
^
drivers/hwtracing/coresight/coresight-etm4x.h:149:2: note: expanded from
macro 'read_etm4x_sysreg_const_offset'
READ_ETM4x_REG(ETM4x_OFFSET_TO_REG(offset))
^
drivers/hwtracing/coresight/coresight-etm4x.h:144:2: note: expanded from
macro 'READ_ETM4x_REG'
read_sysreg_s(ETM4x_REG_NUM_TO_SYSREG((reg)))
^
arch/arm64/include/asm/sysreg.h:1108:15: note: expanded from macro
'read_sysreg_s'
asm volatile(__mrs_s("%0", r) : "=r" (__val)); \
^
arch/arm64/include/asm/sysreg.h:1074:2: note: expanded from macro '__mrs_s'
" mrs_s " v ", " __stringify(r) "\n" \
^
Consider the definitions of TRCSSCSRn and TRCCNTVRn:
drivers/hwtracing/coresight/coresight-etm4x.h:56
#define TRCCNTVRn(n) (0x160 + (n * 4))
drivers/hwtracing/coresight/coresight-etm4x.h:81
#define TRCSSCSRn(n) (0x2A0 + (n * 4))
Where the macro parameter is expanded to i; a loop induction variable
from etm4_disable_hw.
When any compiler can determine that loops may be unrolled, then the
__builtin_constant_p check in read_etm4x_sysreg_offset() defined in
drivers/hwtracing/coresight/coresight-etm4x.h may evaluate to true. This
can lead to the expression `(0x160 + (i * 4))` being passed to
read_etm4x_sysreg_const_offset. Via the trace above, this is passed
through READ_ETM4x_REG, read_sysreg_s, and finally to __mrs_s where it
is string-ified and used directly in inline asm.
Regardless of which compiler or compiler options determine whether a
loop can or can't be unrolled, which determines whether
__builtin_constant_p evaluates to true when passed an expression using a
loop induction variable, it is NEVER safe to allow the preprocessor to
construct inline asm like:
asm volatile (".inst (0x160 + (i * 4))" : "=r"(__val));
^ expected constant expression
Instead of read_etm4x_sysreg_offset() using __builtin_constant_p(), use
__is_constexpr from include/linux/const.h instead to ensure only
expressions that are valid integer constant expressions get passed
through to read_sysreg_s().
This is not a bug in clang; it's a potentially unsafe use of the macro
arguments in read_etm4x_sysreg_offset dependent on __builtin_constant_p.
Link: https://github.com/ClangBuiltLinux/linux/issues/1310
Reported-by: Arnd Bergmann <arnd@kernel.org>
Reported-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220708231520.3958391-1-ndesaulniers@google.com
When enabled, all taken branch addresses are output, even if the branch
was because of a direct branch instruction. This enables reconstruction
of the program flow without having access to the memory image of the
code being executed.
Use bit 8 for the config option which would be the correct bit for
programming ETMv3. Although branch broadcast can't be enabled on ETMv3
because it's not in the define ETM3X_SUPPORTED_OPTIONS, using the
correct bit might help prevent future collisions or allow it to be
enabled if needed.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-2-james.clark@arm.com
The configfs system is a source of access to the config information in the
configuration and feature lists.
This can result in additional LOCKDEP issues as a result of the mutex
ordering between the config list mutex (cscfg_mutex) and the configfs
system mutexes.
As such we need to adjust how load/unload operations work to ensure correct
operation.
1) Previously the cscfg_mutex was held throughout the load/unload
operation. This is now only held during configuration list manipulations,
resulting in a multi-stage load/unload process.
2) All operations that manipulate the configfs representation of the
configurations and features are now separated out and run without the
cscfg_mutex being held. This avoids circular lock_dep issue with the
built-in configfs mutexes and semaphores
3) As the load and unload is now multi-stage, some parts under the
cscfg_mutex and others not:
i) A flag indicating a load / unload operation in progress is used to
serialise load / unload operations.
ii) activating any configuration not possible when unload is in progress.
iii) Configurations have an "available" flag set only after the last load
stage for the configuration is complete. Activation of the configuration
not possible till flag is set.
4) Following load/unload rules remain:
i) Unload prevented while any configuration is active remains.
ii) Unload in strict reverse order of load.
iii) Existing configurations can be activated while a new load operation
is underway. (by definition there can be no dependencies between an
existing configuration and a new loading one due to ii) above.)
Fixes: eb2ec49606 ("coresight: syscfg: Update load API for config loadable modules")
Reported-by: Suzuki Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-and-tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220628173004.30002-3-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Any loaded configurations must be correctly unloaded on coresight module
exit, or issues can arise with nested locking in the configfs directory
code if built with CONFIG_LOCKDEP.
Prior to this patch, the preloaded configuration configfs directory entries
were being unloaded by the recursive code in
configfs_unregister_subsystem().
However, when built with CONFIG_LOCKDEP, this caused a nested lock warning,
which was not mitigated by the LOCKDEP dependent code in fs/configfs/dir.c
designed to prevent this, due to the different directory levels for the
root of the directory being removed.
As the preloaded (and all other) configurations are registered after
configfs_register_subsystem(), we now explicitly unload them before the
call to configfs_unregister_subsystem().
The new routine cscfg_unload_cfgs_on_exit() iterates through the load
owner list to unload any remaining configurations that were not unloaded
by the user before the module exits. This covers both the
CSCFG_OWNER_PRELOAD and CSCFG_OWNER_MODULE owner types, and will be
extended to cover future load owner types for CoreSight configurations.
Fixes: eb2ec49606 ("coresight: syscfg: Update load API for config loadable modules")
Reported-by: Suzuki Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-and-tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220628173004.30002-2-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
coresight devices track their connections (output connections) and
hold a reference to the fwnode. When a device goes away, we walk through
the devices on the coresight bus and make sure that the references
are dropped. This happens both ways:
a) For all output connections from the device, drop the reference to
the target device via coresight_release_platform_data()
b) Iterate over all the devices on the coresight bus and drop the
reference to fwnode if *this* device is the target of the output
connection, via coresight_remove_conns()->coresight_remove_match().
However, the coresight_remove_match() doesn't clear the fwnode field,
after dropping the reference, this causes use-after-free and
additional refcount drops on the fwnode.
e.g., if we have two devices, A and B, with a connection, A -> B.
If we remove B first, B would clear the reference on B, from A
via coresight_remove_match(). But when A is removed, it still has
a connection with fwnode still pointing to B. Thus it tries to drops
the reference in coresight_release_platform_data(), raising the bells
like :
[ 91.990153] ------------[ cut here ]------------
[ 91.990163] refcount_t: addition on 0; use-after-free.
[ 91.990212] WARNING: CPU: 0 PID: 461 at lib/refcount.c:25 refcount_warn_saturate+0xa0/0x144
[ 91.990260] Modules linked in: coresight_funnel coresight_replicator coresight_etm4x(-)
crct10dif_ce coresight ip_tables x_tables ipv6 [last unloaded: coresight_cpu_debug]
[ 91.990398] CPU: 0 PID: 461 Comm: rmmod Tainted: G W T 5.19.0-rc2+ #53
[ 91.990418] Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Feb 1 2019
[ 91.990434] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 91.990454] pc : refcount_warn_saturate+0xa0/0x144
[ 91.990476] lr : refcount_warn_saturate+0xa0/0x144
[ 91.990496] sp : ffff80000c843640
[ 91.990509] x29: ffff80000c843640 x28: ffff800009957c28 x27: ffff80000c8439a8
[ 91.990560] x26: ffff00097eff1990 x25: ffff8000092b6ad8 x24: ffff00097eff19a8
[ 91.990610] x23: ffff80000c8439a8 x22: 0000000000000000 x21: ffff80000c8439c2
[ 91.990659] x20: 0000000000000000 x19: ffff00097eff1a10 x18: ffff80000ab99c40
[ 91.990708] x17: 0000000000000000 x16: 0000000000000000 x15: ffff80000abf6fa0
[ 91.990756] x14: 000000000000001d x13: 0a2e656572662d72 x12: 657466612d657375
[ 91.990805] x11: 203b30206e6f206e x10: 6f69746964646120 x9 : ffff8000081aba28
[ 91.990854] x8 : 206e6f206e6f6974 x7 : 69646461203a745f x6 : 746e756f63666572
[ 91.990903] x5 : ffff00097648ec58 x4 : 0000000000000000 x3 : 0000000000000027
[ 91.990952] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff00080260ba00
[ 91.991000] Call trace:
[ 91.991012] refcount_warn_saturate+0xa0/0x144
[ 91.991034] kobject_get+0xac/0xb0
[ 91.991055] of_node_get+0x2c/0x40
[ 91.991076] of_fwnode_get+0x40/0x60
[ 91.991094] fwnode_handle_get+0x3c/0x60
[ 91.991116] fwnode_get_nth_parent+0xf4/0x110
[ 91.991137] fwnode_full_name_string+0x48/0xc0
[ 91.991158] device_node_string+0x41c/0x530
[ 91.991178] pointer+0x320/0x3ec
[ 91.991198] vsnprintf+0x23c/0x750
[ 91.991217] vprintk_store+0x104/0x4b0
[ 91.991238] vprintk_emit+0x8c/0x360
[ 91.991257] vprintk_default+0x44/0x50
[ 91.991276] vprintk+0xcc/0xf0
[ 91.991295] _printk+0x68/0x90
[ 91.991315] of_node_release+0x13c/0x14c
[ 91.991334] kobject_put+0x98/0x114
[ 91.991354] of_node_put+0x24/0x34
[ 91.991372] of_fwnode_put+0x40/0x5c
[ 91.991390] fwnode_handle_put+0x38/0x50
[ 91.991411] coresight_release_platform_data+0x74/0xb0 [coresight]
[ 91.991472] coresight_unregister+0x64/0xcc [coresight]
[ 91.991525] etm4_remove_dev+0x64/0x78 [coresight_etm4x]
[ 91.991563] etm4_remove_amba+0x1c/0x2c [coresight_etm4x]
[ 91.991598] amba_remove+0x3c/0x19c
Reproducible by: (Build all coresight components as modules):
#!/bin/sh
while true
do
for m in tmc stm cpu_debug etm4x replicator funnel
do
modprobe coresight_${m}
done
for m in tmc stm cpu_debug etm4x replicator funnel
do
rmmode coresight_${m}
done
done
Cc: stable@vger.kernel.org
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Fixes: 37ea1ffddf ("coresight: Use fwnode handle instead of device names")
Link: https://lore.kernel.org/r/20220614214024.3005275-1-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Per discussion in [1], it was decided to move to using architecture
independent/asm-generic IO memory barriers to have just one set of
them and deprecate use of arm64 specific IO memory barriers in driver
code. So replace current usage of __io_rmb()/__iowmb() in drivers to
__io_ar()/__io_bw().
[1] https://lore.kernel.org/lkml/CAK8P3a0L2tLeF1Q0+0ijUxhGNaw+Z0fyPC1oW6_ELQfn0=i4iw@mail.gmail.com/
Signed-off-by: Sai Prakash Ranjan <quic_saipraka@quicinc.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The panic notifier infrastructure executes registered callbacks when
a panic event happens - such callbacks are executed in atomic context,
with interrupts and preemption disabled in the running CPU and all other
CPUs disabled. That said, mutexes in such context are not a good idea.
This patch replaces a regular mutex with a mutex_trylock safer approach;
given the nature of the mutex used in the driver, it should be pretty
uncommon being unable to acquire such mutex in the panic path, hence
no functional change should be observed (and if it is, that would be
likely a deadlock with the regular mutex).
Fixes: 2227b7c746 ("coresight: add support for CPU debug module")
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220427224924.592546-10-gpiccoli@igalia.com
It is possibe that probe failure issue happens when the device
and its child_device's probe happens at the same time.
In coresight_make_links, has_conns_grp is true for parent, but
has_conns_grp is false for child device as has_conns_grp is set
to true in coresight_create_conns_sysfs_group. The probe of parent
device will fail at this condition. Add has_conns_grp check for
child device before make the links and make the process from
device_register to connection_create be atomic to avoid this
probe failure issue.
Cc: stable@vger.kernel.org
Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Suggested-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Link: https://lore.kernel.org/r/20220309142206.15632-1-quic_jinlmao@quicinc.com
[ Added Cc stable ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-16-james.clark@arm.com
/* Removed extra new lines */
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-15-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-14-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-13-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-12-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. These fields already have macros
to define them so use them instead of magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-11-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-10-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-9-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-8-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-7-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-6-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-5-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-4-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-3-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
This is a no-op change for style and consistency and has no effect on
the binary output by the compiler. In sysreg.h fields are defined as
the register name followed by the field name and then _MASK. This
allows for grepping for fields by name rather than using magic numbers.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220304171913.2292458-2-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Here is the big set of char/misc and other small driver subsystem
updates for 5.18-rc1.
Included in here are merges from driver subsystems which contain:
- iio driver updates and new drivers
- fsi driver updates
- fpga driver updates
- habanalabs driver updates and support for new hardware
- soundwire driver updates and new drivers
- phy driver updates and new drivers
- coresight driver updates
- icc driver updates
Individual changes include:
- mei driver updates
- interconnect driver updates
- new PECI driver subsystem added
- vmci driver updates
- lots of tiny misc/char driver updates
There will be two merge conflicts with your tree, one in MAINTAINERS
which is obvious to fix up, and one in drivers/phy/freescale/Kconfig
which also should be easy to resolve.
All of these have been in linux-next for a while with no reported
problems.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc and other driver updates from Greg KH:
"Here is the big set of char/misc and other small driver subsystem
updates for 5.18-rc1.
Included in here are merges from driver subsystems which contain:
- iio driver updates and new drivers
- fsi driver updates
- fpga driver updates
- habanalabs driver updates and support for new hardware
- soundwire driver updates and new drivers
- phy driver updates and new drivers
- coresight driver updates
- icc driver updates
Individual changes include:
- mei driver updates
- interconnect driver updates
- new PECI driver subsystem added
- vmci driver updates
- lots of tiny misc/char driver updates
All of these have been in linux-next for a while with no reported
problems"
* tag 'char-misc-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (556 commits)
firmware: google: Properly state IOMEM dependency
kgdbts: fix return value of __setup handler
firmware: sysfb: fix platform-device leak in error path
firmware: stratix10-svc: add missing callback parameter on RSU
arm64: dts: qcom: add non-secure domain property to fastrpc nodes
misc: fastrpc: Add dma handle implementation
misc: fastrpc: Add fdlist implementation
misc: fastrpc: Add helper function to get list and page
misc: fastrpc: Add support to secure memory map
dt-bindings: misc: add fastrpc domain vmid property
misc: fastrpc: check before loading process to the DSP
misc: fastrpc: add secure domain support
dt-bindings: misc: add property to support non-secure DSP
misc: fastrpc: Add support to get DSP capabilities
misc: fastrpc: add support for FASTRPC_IOCTL_MEM_MAP/UNMAP
misc: fastrpc: separate fastrpc device from channel context
dt-bindings: nvmem: brcm,nvram: add basic NVMEM cells
dt-bindings: nvmem: make "reg" property optional
nvmem: brcm_nvram: parse NVRAM content into NVMEM cells
nvmem: dt-bindings: Fix the error of dt-bindings check
...
CORESIGHT_DEV_TYPE_NONE/CORESIGHT_DEV_SUBTYPE_XXXX_NONE values are not used
any where. Actual enumeration can start from 0. Just drop these unused enum
values.
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1645005118-10561-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
ETMv3 driver enables PID tracing by directly using perf config from
userspace, this means the tracer will capture PID packets from root
namespace but the profiling session runs in non-root PID namespace.
Finally, the recorded packets can mislead perf reporting with the
mismatched PID values.
This patch changes to only enable PID tracing for root PID namespace.
Note, the hardware supports VMID tracing from ETMv3.5, but the driver
never enables VMID trace, this patch doesn't handle VMID trace (bit 30
in ETMCR register) particularly.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220204152403.71775-5-leo.yan@linaro.org
As commented in the function ctxid_pid_store(), it can cause the PID
values mismatching between context ID tracing and PID allocated in a
non-root namespace.
For this reason, when a process runs in non-root PID namespace, the
driver doesn't allow PID tracing and returns failure when access
contextID related sysfs nodes.
VMID works for virtual contextID when the kernel runs in EL2 mode with
VHE; on the other hand, the driver doesn't prevent users from accessing
it when programs run in the non-root namespace. Thus this can lead
to same issues with contextID described above.
This patch imposes the checking on VMID related sysfs knobs and returns
failure if current process runs in non-root PID namespace.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220204152403.71775-3-leo.yan@linaro.org
Updates to the values and the index are protected via the spinlock.
Ensure we use the same lock to read the value safely.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220204152403.71775-2-leo.yan@linaro.org
Currently with the check present in the module initialisation, it shouts
on all the systems irrespective of presence of coresight trace buffer
extensions.
Similar to Arm SPE perf driver, move the check for kernel page table
isolation from EL0 to the device probe stage instead of the module
initialisation so that it complains only on the systems that support TRBE.
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: coresight@lists.linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220203190159.3145272-1-sudeep.holla@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
The spec says this:
P0 tracing support field. The permitted values are:
0b00 Tracing of load and store instructions as P0 elements is not
supported.
0b11 Tracing of load and store instructions as P0 elements is
supported, so TRCCONFIGR.INSTP0 is supported.
All other values are reserved.
The value we are looking for is 0b11 so simplify this. The double read
and && was a bit obfuscated.
Suggested-by: Suzuki Poulose <suzuki.poulose@arm.com>
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20220203115336.119735-2-james.clark@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Replace acpi_bus_get_device() that is going to be dropped with
acpi_fetch_acpi_dev().
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/5790600.lOV4Wx5bFT@kreacher
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
device_register() calls device_initialize(),
according to doc of device_initialize:
Use put_device() to give up your reference instead of freeing
* @dev directly once you have called this function.
To prevent potential memleak, use put_device() for error handling.
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Fixes: 85e2414c51 ("coresight: syscfg: Initial coresight system configuration")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220124124121.8888-1-linmq006@gmail.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
It's impossible to program a valid value for TRCCONFIGR.QE
when TRCIDR0.QSUPP==0b10. In that case the following is true:
Q element support is implemented, and only supports Q elements without
instruction counts. TRCCONFIGR.QE can only take the values 0b00 or 0b11.
Currently the low bit of QSUPP is checked to see if the low bit of QE can
be written to, but as you can see when QSUPP==0b10 the low bit is cleared
making it impossible to ever write the only valid value of 0b11 to QE.
0b10 would be written instead, which is a reserved QE value even for all
values of QSUPP.
The fix is to allow writing the low bit of QE for any non zero value of
QSUPP.
This change also ensures that the low bit is always set, even when the
user attempts to only set the high bit.
Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Fixes: d8c6696208 ("coresight-etm4x: Controls pertaining to the reset, mode, pe and events")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220120113047.2839622-2-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
TRBE implementations affected by Arm erratum #1902691 might corrupt trace
data or deadlock, when it's being written into the memory. Workaround this
problem in the driver, by preventing TRBE initialization on affected cpus.
The firmware must have disabled the access to TRBE for the kernel on such
implementations. This will cover the kernel for any firmware that doesn't
do this already. This just updates the TRBE driver as required.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1643120437-14352-8-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
TRBE implementations affected by Arm erratum #2038923 might get TRBE into
an inconsistent view on whether trace is prohibited within the CPU. As a
result, the trace buffer or trace buffer state might be corrupted. This
happens after TRBE buffer has been enabled by setting TRBLIMITR_EL1.E,
followed by just a single context synchronization event before execution
changes from a context, in which trace is prohibited to one where it isn't,
or vice versa. In these mentioned conditions, the view of whether trace is
prohibited is inconsistent between parts of the CPU, and the trace buffer
or the trace buffer state might be corrupted.
Work around this problem in the TRBE driver by preventing an inconsistent
view of whether the trace is prohibited or not based on TRBLIMITR_EL1.E by
immediately following a change to TRBLIMITR_EL1.E with at least one ISB
instruction before an ERET, or two ISB instructions if no ERET is to take
place. This just updates the TRBE driver as required.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1643120437-14352-7-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
TRBE implementations affected by Arm erratum #2064142 might fail to write
into certain system registers after the TRBE has been disabled. Under some
conditions after TRBE has been disabled, writes into certain TRBE registers
TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1 and TRBTRG_EL1 will be
ignored and not be effected.
Work around this problem in the TRBE driver by executing TSB CSYNC and DSB
just after the trace collection has stopped and before performing a system
register write to one of the affected registers. This just updates the TRBE
driver as required.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki Poulose <suzuki.poulose@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/1643120437-14352-6-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].
This code was transformed with the help of Coccinelle:
(next-20220214$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)
@@
identifier S, member, array;
type T1, T2;
@@
struct S {
...
T1 member;
T2 array[
- 0
];
};
UAPI and wireless changes were intentionally excluded from this patch
and will be sent out separately.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/78
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
The double `the' in the comment in line 732 is repeated. Remove one
of them from the comment.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Link: https://lore.kernel.org/r/20211211090221.241529-1-wangborong@cdjrlc.com
[Fixed capital letter in title]
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Adds configfs attributes to allow a configuration to be enabled for use
when sysfs is used to control CoreSight.
perf retains independent enabling of configurations.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20211124200038.28662-6-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
CoreSight configurations and features can be added as kernel loadable
modules. This patch updates the load owner API to ensure that the module
cannot be unloaded either:
1) if the config it supplies is in use
2) if the module is not the last in the load order list.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20211124200038.28662-4-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Expand the configuration API to allow dynamic runtime load and unload of
configurations and features.
On load, configurations and features are tagged with a "load owner" that
is used to determine sets that were loaded together in a given API call.
To unload the API uses the load owner to unload all elements previously
loaded by that owner.
The API also records the order in which different owners loaded
their elements into the system. Later loading configurations can use
previously loaded features, creating load dependencies. Therefore unload
is enforced strictly in the reverse order to load.
A load owner will be an additional loadable module, or a configuration
loaded via configfs.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20211124200038.28662-3-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Update the existing load API to introduce a "load owner" concept.
This allows the tracking of the loaded configurations and features against
the loading owner type, to allow later unload according to owner.
A list of loaded configurations by owner is created.
The load owner infrastructure will be used in following patches
to implement dynanic load and unload, alongside dependency tracking.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20211124200038.28662-2-mike.leach@linaro.org
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
TRBE implementations affected by Arm erratum (2253138 or 2224489), could
write to the next address after the TRBLIMITR.LIMIT, instead of wrapping
to the TRBBASER. This implies that the TRBE could potentially corrupt :
- A page used by the rest of the kernel/user (if the LIMIT = end of
perf ring buffer)
- A page within the ring buffer, but outside the driver's range.
[head, head + size]. This may contain some trace data, may be
consumed by the userspace.
We workaround this erratum by :
- Making sure that there is at least an extra PAGE space left in the
TRBE's range than we normally assign. This will be additional to other
restrictions (e.g, the TRBE alignment for working around
TRBE_WORKAROUND_OVERWRITE_IN_FILL_MODE, where there is a minimum of
PAGE_SIZE. Thus we would have 2 * PAGE_SIZE)
- Adjust the LIMIT to leave the last PAGE_SIZE out of the TRBE's allowed
range (i.e, TRBEBASER...TRBLIMITR.LIMIT), by :
TRBLIMITR.LIMIT -= PAGE_SIZE
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-14-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
The TRBE driver makes sure that there is enough space for a meaningful
run, otherwise pads the given space and restarts the offset calculation
once. But there is no guarantee that we may find space or hit "no space".
Make sure that we repeat the step until, either :
- We have the minimum space
OR
- There is NO space at all.
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-13-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
For the TRBE to operate, we need a minimum space available to collect
meaningful trace session. This is currently a few bytes, but we may need
to extend this for working around errata. So, abstract this into a helper
function.
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-12-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
ARM Neoverse-N2 (#2139208) and Cortex-A710(##2119858) suffers from
an erratum, which when triggered, might cause the TRBE to overwrite
the trace data already collected in FILL mode, in the event of a WRAP.
i.e, the TRBE doesn't stop writing the data, instead wraps to the base
and could write upto 3 cache line size worth trace. Thus, this could
corrupt the trace at the "BASE" pointer.
The workaround is to program the write pointer 256bytes from the
base, such that if the erratum is triggered, it doesn't overwrite
the trace data that was captured. This skipped region could be
padded with ignore packets at the end of the session, so that
the decoder sees a continuous buffer with some padding at the
beginning. The trace data written at the base is considered
lost as the limit could have been in the middle of the perf
ring buffer, and jumping to the "base" is not acceptable.
We set the flags already to indicate that some amount of trace
was lost during the FILL event IRQ. So this is fine.
One important change with the work around is, we program the
TRBBASER_EL1 to current page where we are allowed to write.
Otherwise, it could overwrite a region that may be consumed
by the perf. Towards this, we always make sure that the
"handle->head" and thus the trbe_write is PAGE_SIZE aligned,
so that we can set the BASE to the PAGE base and move the
TRBPTR to the 256bytes offset.
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-11-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Add a minimal infrastructure to keep track of the errata
affecting the given TRBE instance. Given that we have
heterogeneous CPUs, we have to manage the list per-TRBE
instance to be able to apply the work around as needed.
Thus we will need to check if individual CPUs are affected
by the erratum.
We rely on the arm64 errata framework for the actual
description and the discovery of a given erratum, to
keep the Erratum work around at a central place and
benefit from the code and the advertisement from the
kernel. Though we could reuse the "this_cpu_has_cap()"
to apply an erratum work around, it is a bit of a heavy
operation, as it must go through the "erratum" detection
check on the CPU every time it is called (e.g, scanning
through a table of affected MIDRs). Since we need
to do this check for every session, may be multiple
times (depending on the wrok around), we could save
the cycles by caching the affected errata per-CPU
instance in the per-CPU struct trbe_cpudata.
Since we are only interested in the errata affecting
the TRBE driver, we only need to track a very few of them
per-CPU. Thus we use a local mapping of the CPUCAP for the
erratum to avoid bloating up a bitmap for trbe_cpudata.
i.e, each arm64 TRBE erratum bit is assigned a "index"
within the driver to track. Each trbe instance updates
the list of affected erratum at probe time on the CPU.
This makes sure that we can easily access the list of
errata on a given TRBE instance without much overhead.
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20211019163153.3692640-10-suzuki.poulose@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Linus Torvalds