From 14ea4db18c069816e7ff0441a2f39a12d2feb11c Mon Sep 17 00:00:00 2001 From: Mike Leach Date: Wed, 16 Sep 2020 13:17:37 -0600 Subject: [PATCH] coresight: etm4x: Fix number of resources check for ETM 4.3 and above The initialisation code checks TRCIDR4 to determine the number of resource selectors available on the system. Since ETM v 4.3, the value 0 has a different meaning. This patch takes into account this change. Signed-off-by: Mike Leach [Removed '.' in patch title, added stable] Signed-off-by: Mathieu Poirier Link: https://lore.kernel.org/r/20200916191737.4001561-17-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-etm4x.c | 8 +++++++- drivers/hwtracing/coresight/coresight-etm4x.h | 3 +++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index b29ad4f7fac2..f5ab13aaecea 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -742,8 +742,14 @@ static void etm4_init_arch_data(void *info) * The number of resource pairs conveyed by the HW starts at 0, i.e a * value of 0x0 indicate 1 resource pair, 0x1 indicate two and so on. * As such add 1 to the value of NUMRSPAIR for a better representation. + * + * For ETM v4.3 and later, 0x0 means 0, and no pairs are available - + * the default TRUE and FALSE resource selectors are omitted. + * Otherwise for values 0x1 and above the number is N + 1 as per v4.2. */ - drvdata->nr_resource = BMVAL(etmidr4, 16, 19) + 1; + drvdata->nr_resource = BMVAL(etmidr4, 16, 19); + if ((drvdata->arch < ETM4X_ARCH_4V3) || (drvdata->nr_resource > 0)) + drvdata->nr_resource += 1; /* * NUMSSCC, bits[23:20] the number of single-shot * comparator control for tracing. Read any status regs as these diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h index 5259f96fd28a..eefc7371c6c4 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.h +++ b/drivers/hwtracing/coresight/coresight-etm4x.h @@ -200,6 +200,9 @@ /* NS MON (EL3) mode never implemented */ #define ETM_EXLEVEL_NS_VICTLR_MASK GENMASK(22, 20) +/* Interpretation of resource numbers change at ETM v4.3 architecture */ +#define ETM4X_ARCH_4V3 0x43 + /** * struct etmv4_config - configuration information related to an ETMv4 * @mode: Controls various modes supported by this ETM. -- GitLab