[PATCH] Coresight: ETMv4: Prevent TRCRSCTLR0&1 from being accessed
From: Chunyan Zhang <hidden>
Date: 2015-08-27 04:09:05
1. TRCRSCTLRn - Resource Selection Control Registers n=0~1 are reserved, we shouldn't access them. 2. The max number of 'n' here is defined in TRCIDR4.NUMRSPAIR whoes value indicates the number of resource selection *pairs*, and 0 indicates one resource selection pair, 1 indicates two pairs, and so on ... So, the total number of resource selection control registers which we can access is (TRCIDR4.NUMRSPAIR * 2) Signed-off-by: Chunyan Zhang <redacted> --- drivers/hwtracing/coresight/coresight-etm4x.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 1312e99..9425249 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c@@ -136,7 +136,9 @@ static void etm4_enable_hw(void *info) writel_relaxed(drvdata->cntr_val[i], drvdata->base + TRCCNTVRn(i)); } - for (i = 0; i < drvdata->nr_resource; i++) + + /* Resource selector pair 0 is always implemented and reserved */ + for (i = 2; i < (drvdata->nr_resource + 1) * 2; i++) writel_relaxed(drvdata->res_ctrl[i], drvdata->base + TRCRSCTLRn(i));
@@ -489,8 +491,9 @@ static ssize_t reset_store(struct device *dev, drvdata->cntr_val[i] = 0x0; } - drvdata->res_idx = 0x0; - for (i = 0; i < drvdata->nr_resource; i++) + /* Resource selector pair 0 is always implemented and reserved */ + drvdata->res_idx = 0x2; + for (i = 2; i < (drvdata->nr_resource + 1) * 2; i++) drvdata->res_ctrl[i] = 0x0; for (i = 0; i < drvdata->nr_ss_cmp; i++) {
@@ -1729,7 +1732,7 @@ static ssize_t res_idx_store(struct device *dev, if (kstrtoul(buf, 16, &val)) return -EINVAL; /* Resource selector pair 0 is always implemented and reserved */ - if ((val == 0) || (val >= drvdata->nr_resource)) + if (val < 2 || val > (drvdata->nr_resource + 1) * 2) return -EINVAL; /*
@@ -2498,7 +2501,9 @@ static void etm4_init_default_data(struct etmv4_drvdata *drvdata) drvdata->cntr_val[i] = 0x0; } - for (i = 2; i < drvdata->nr_resource * 2; i++) + /* Resource selector pair 0 is always implemented and reserved */ + drvdata->res_idx = 0x2; + for (i = 2; i < (drvdata->nr_resource + 1) * 2; i++) drvdata->res_ctrl[i] = 0x0; for (i = 0; i < drvdata->nr_ss_cmp; i++) {
--
1.9.1