If the CPU implements Arm v8.4 Trace filter controls (FEAT_TRF), move the ETM to trace prohibited region using TRFCR, while disabling.
Cc: Mathieu Poirier mathieu.poirier@linaro.org Cc: Mike Leach mike.leach@linaro.org Cc: Anshuman Khandual anshuman.khandual@arm.com Reviewed-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com --- .../coresight/coresight-etm4x-core.c | 21 +++++++++++++++++-- drivers/hwtracing/coresight/coresight-etm4x.h | 2 ++ 2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c index 15016f757828..00297906669c 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -31,6 +31,7 @@ #include <linux/pm_runtime.h> #include <linux/property.h>
+#include <asm/barrier.h> #include <asm/sections.h> #include <asm/sysreg.h> #include <asm/local.h> @@ -654,6 +655,7 @@ static int etm4_enable(struct coresight_device *csdev, static void etm4_disable_hw(void *info) { u32 control; + u64 trfcr; struct etmv4_drvdata *drvdata = info; struct etmv4_config *config = &drvdata->config; struct coresight_device *csdev = drvdata->csdev; @@ -676,6 +678,16 @@ static void etm4_disable_hw(void *info) /* EN, bit[0] Trace unit enable bit */ control &= ~0x1;
+ /* + * If the CPU supports v8.4 Trace filter Control, + * set the ETM to trace prohibited region. + */ + if (drvdata->trfc) { + trfcr = read_sysreg_s(SYS_TRFCR_EL1); + write_sysreg_s(trfcr & ~(TRFCR_ELx_ExTRE | TRFCR_ELx_E0TRE), + SYS_TRFCR_EL1); + isb(); + } /* * Make sure everything completes before disabling, as recommended * by section 7.3.77 ("TRCVICTLR, ViewInst Main Control Register, @@ -683,12 +695,16 @@ static void etm4_disable_hw(void *info) */ dsb(sy); isb(); + /* Trace synchronization barrier, is a nop if not supported */ + tsb_csync(); etm4x_relaxed_write32(csa, control, TRCPRGCTLR);
/* wait for TRCSTATR.PMSTABLE to go to '1' */ if (coresight_timeout(csa, TRCSTATR, TRCSTATR_PMSTABLE_BIT, 1)) dev_err(etm_dev, "timeout while waiting for PM stable Trace Status\n"); + if (drvdata->trfc) + write_sysreg_s(trfcr, SYS_TRFCR_EL1);
/* read the status of the single shot comparators */ for (i = 0; i < drvdata->nr_ss_cmp; i++) { @@ -873,7 +889,7 @@ static bool etm4_init_csdev_access(struct etmv4_drvdata *drvdata, return false; }
-static void cpu_enable_tracing(void) +static void cpu_enable_tracing(struct etmv4_drvdata *drvdata) { u64 dfr0 = read_sysreg(id_aa64dfr0_el1); u64 trfcr; @@ -881,6 +897,7 @@ static void cpu_enable_tracing(void) if (!cpuid_feature_extract_unsigned_field(dfr0, ID_AA64DFR0_TRACE_FILT_SHIFT)) return;
+ drvdata->trfc = true; /* * If the CPU supports v8.4 SelfHosted Tracing, enable * tracing at the kernel EL and EL0, forcing to use the @@ -1082,7 +1099,7 @@ static void etm4_init_arch_data(void *info) /* NUMCNTR, bits[30:28] number of counters available for tracing */ drvdata->nr_cntr = BMVAL(etmidr5, 28, 30); etm4_cs_lock(drvdata, csa); - cpu_enable_tracing(); + cpu_enable_tracing(drvdata); }
static inline u32 etm4_get_victlr_access_type(struct etmv4_config *config) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 0af60571aa23..f6478ef642bf 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -862,6 +862,7 @@ struct etmv4_save_state { * @nooverflow: Indicate if overflow prevention is supported. * @atbtrig: If the implementation can support ATB triggers * @lpoverride: If the implementation can support low-power state over. + * @trfc: If the implementation supports Arm v8.4 trace filter controls. * @config: structure holding configuration parameters. * @save_state: State to be preserved across power loss * @state_needs_restore: True when there is context to restore after PM exit @@ -912,6 +913,7 @@ struct etmv4_drvdata { bool nooverflow; bool atbtrig; bool lpoverride; + bool trfc; struct etmv4_config config; struct etmv4_save_state *save_state; bool state_needs_restore;