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2022-09-21arm64/sysreg: Fix a few missed conversionsNathan Chancellor2-3/+4
After the conversion to automatically generating the ID_AA64DFR0_EL1 definition names, the build fails in a few different places because some of the definitions were not changed to their new names along the way. Update the names to resolve the build errors. Fixes: c0357a73fa4a ("arm64/sysreg: Align field names in ID_AA64DFR0_EL1 with architecture") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/r/20220919160928.3905780-1-nathan@kernel.org Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-08-05Merge tag 'asm-generic-6.0' of ↵Linus Torvalds2-8/+8
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.
2022-07-11coresight: etm4x: avoid build failure with unrolled loopsNick Desaulniers1-1/+2
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
2022-07-06coresight: Add config flag to enable branch broadcastJames Clark2-0/+16
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
2022-06-29coresight: syscfg: Update load and unload operationsMike Leach3-41/+165
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: eb2ec49606c2 ("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>
2022-06-29coresight: configfs: Fix unload of configurations on module exitMike Leach1-11/+93
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: eb2ec49606c2 ("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>
2022-06-22coresight: Clear the connection field properlySuzuki K Poulose1-0/+1
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: 37ea1ffddffa ("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>
2022-06-15coresight: etm4x: Use asm-generic IO memory barriersSai Prakash Ranjan2-8/+8
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>
2022-05-09coresight: cpu-debug: Replace mutex with mutex_trylock on panic notifierGuilherme G. Piccoli1-3/+4
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: 2227b7c74634 ("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
2022-05-04coresight: core: Fix coresight device probe failure issueMao Jinlong1-11/+22
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>
2022-04-13coresight: etm4x: Cleanup TRCRSCTLRn register accessesJames Clark2-2/+10
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>
2022-04-13coresight: etm4x: Cleanup TRCBBCTLR register accessesJames Clark2-2/+5
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>
2022-04-13coresight: etm4x: Cleanup TRCSSPCICRn register accessesJames Clark2-1/+3
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>
2022-04-13coresight: etm4x: Cleanup TRCSSCCRn and TRCSSCSRn register accessesJames Clark3-4/+8
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>
2022-04-13coresight: etm4x: Cleanup TRCACATRn register accessesJames Clark2-25/+31
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>
2022-04-13coresight: etm3x: Cleanup ETMTECR1 register accessesJames Clark2-2/+2
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>
2022-04-13coresight: etm4x: Cleanup TRCVICTLR register accessesJames Clark3-37/+31
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>
2022-04-13coresight: etm4x: Cleanup TRCSTALLCTLR register accessesJames Clark2-6/+10
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>
2022-04-13coresight: etm4x: Cleanup TRCEVENTCTL1R register accessesJames Clark2-10/+23
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>
2022-04-13coresight: etm4x: Cleanup TRCCONFIGR register accessesJames Clark3-30/+44
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>
2022-04-13coresight: etm4x: Cleanup TRCIDR5 register accessesJames Clark2-12/+13
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>
2022-04-13coresight: etm4x: Cleanup TRCIDR4 register accessesJames Clark2-6/+14
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>
2022-04-13coresight: etm4x: Cleanup TRCIDR3 register accessesJames Clark2-30/+20
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>
2022-04-13coresight: etm4x: Cleanup TRCIDR2 register accessesJames Clark2-3/+7
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>
2022-04-13coresight: etm4x: Cleanup TRCIDR0 register accessesJames Clark2-28/+21
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>
2022-03-28Merge tag 'char-misc-5.18-rc1' of ↵Linus Torvalds8-54/+146
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 ...
2022-03-11coresight: Drop unused 'none' enum value for each componentAnshuman Khandual1-3/+0
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>
2022-03-11coresight: etm3x: Don't trace PID for non-root PID namespaceLeo Yan1-0/+4
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
2022-03-11coresight: etm4x: Don't trace PID for non-root PID namespaceLeo Yan1-2/+8
When runs in perf mode, the driver always enables the PID tracing. This can lead confusion when the profiling session runs in non-root PID namespace, whereas it records the PIDs from the root PID namespace. To avoid confusion for PID tracing, when runs in perf mode, this patch changes to only enable PID tracing for root PID namespace. As result, after apply this patch, the perf tool reports PID as '-1' for all samples: # unshare --fork --pid perf record -e cs_etm// -m 64K,64K -a \ -o perf_test.data -- uname # perf report -i perf_test.data --itrace=Zi1000i --stdio # Total Lost Samples: 0 # # Samples: 94 of event 'instructions' # Event count (approx.): 94000 # # Overhead Command Shared Object Symbol # ........ ....... ................. .............................. # 68.09% :-1 [kernel.kallsyms] [k] __sched_text_end 3.19% :-1 [kernel.kallsyms] [k] hrtimer_interrupt 2.13% :-1 [kernel.kallsyms] [k] __bitmap_and 2.13% :-1 [kernel.kallsyms] [k] trace_vbprintk 1.06% :-1 [kernel.kallsyms] [k] __fget_files 1.06% :-1 [kernel.kallsyms] [k] __schedule 1.06% :-1 [kernel.kallsyms] [k] __softirqentry_text_start 1.06% :-1 [kernel.kallsyms] [k] __update_load_avg_cfs_rq 1.06% :-1 [kernel.kallsyms] [k] __update_load_avg_se 1.06% :-1 [kernel.kallsyms] [k] arch_counter_get_cntpct 1.06% :-1 [kernel.kallsyms] [k] check_and_switch_context 1.06% :-1 [kernel.kallsyms] [k] format_decode 1.06% :-1 [kernel.kallsyms] [k] handle_percpu_devid_irq 1.06% :-1 [kernel.kallsyms] [k] irq_enter_rcu 1.06% :-1 [kernel.kallsyms] [k] irqtime_account_irq 1.06% :-1 [kernel.kallsyms] [k] ktime_get 1.06% :-1 [kernel.kallsyms] [k] ktime_get_coarse_real_ts64 1.06% :-1 [kernel.kallsyms] [k] memmove 1.06% :-1 [kernel.kallsyms] [k] perf_ioctl 1.06% :-1 [kernel.kallsyms] [k] perf_output_begin 1.06% :-1 [kernel.kallsyms] [k] perf_output_copy 1.06% :-1 [kernel.kallsyms] [k] profile_tick 1.06% :-1 [kernel.kallsyms] [k] sched_clock 1.06% :-1 [kernel.kallsyms] [k] timerqueue_add 1.06% :-1 [kernel.kallsyms] [k] trace_save_cmdline 1.06% :-1 [kernel.kallsyms] [k] update_load_avg 1.06% :-1 [kernel.kallsyms] [k] vbin_printf 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/20220204152403.71775-4-leo.yan@linaro.org
2022-03-11coresight: etm4x: Don't use virtual contextID for non-root PID namespaceLeo Yan1-0/+28
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
2022-03-11coresight: etm4x: Add lock for reading virtual context ID comparatorLeo Yan1-0/+2
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
2022-03-11coresight: trbe: Move check for kernel page table isolation from EL0 to probeSudeep Holla1-5/+6
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>
2022-03-11coresight: no-op refactor to make INSTP0 check more idiomaticJames Clark1-1/+1
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>
2022-03-11hwtracing: coresight: Replace acpi_bus_get_device()Rafael J. Wysocki1-4/+4
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>
2022-03-11coresight: syscfg: Fix memleak on registration failure in cscfg_create_deviceMiaoqian Lin1-1/+1
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: 85e2414c518a ("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>
2022-03-11coresight: Fix TRCCONFIGR.QE sysfs interfaceJames Clark1-2/+6
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: d8c66962084f ("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>
2022-03-11coresight: trbe: Work around the trace data corruptionAnshuman Khandual1-0/+12
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>
2022-03-11coresight: trbe: Work around the invalid prohibited statesAnshuman Khandual1-12/+36
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>
2022-03-11coresight: trbe: Work around the ignored system register writesAnshuman Khandual2-24/+38
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>
2022-02-17treewide: Replace zero-length arrays with flexible-array membersGustavo A. R. Silva1-1/+1
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>
2021-12-13coresight: core: Fix typo in a commentJason Wang1-1/+1
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>
2021-11-26coresight: configfs: Allow configfs to activate configurationMike Leach5-28/+186
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>
2021-11-26coresight: syscfg: Update load API for config loadable modulesMike Leach2-1/+39
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>
2021-11-26coresight: configuration: Update API to permit dynamic load/unloadMike Leach5-0/+160
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>
2021-11-26coresight: configuration: Update API to introduce load owner conceptMike Leach4-8/+56
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>
2021-11-16coresight: Use devm_bitmap_zalloc when applicableChristophe JAILLET1-7/+3
'drvdata->chs.guaranteed' is a bitmap. So use 'devm_bitmap_kzalloc()' to simplify code, improve the semantic and avoid some open-coded arithmetic in allocator arguments. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Link: https://lore.kernel.org/r/a4b8454f560b70cedf0e4d06275787f08d576ee5.1635964610.git.christophe.jaillet@wanadoo.fr Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
2021-10-27coresight: trbe: Work around write to out of rangeSuzuki K Poulose1-1/+62
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>
2021-10-27coresight: trbe: Make sure we have enough spaceSuzuki K Poulose1-1/+5
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>
2021-10-27coresight: trbe: Add a helper to determine the minimum buffer sizeSuzuki K Poulose1-1/+6
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>
2021-10-27coresight: trbe: Workaround TRBE errata overwrite in FILL modeSuzuki K Poulose1-11/+157
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>