summaryrefslogtreecommitdiffstats
path: root/drivers/hwtracing/coresight
diff options
context:
space:
mode:
authorChunyan Zhang <zhang.chunyan@linaro.org>2015-10-07 17:26:38 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-10-07 18:54:09 +0200
commit497b59565b25d6dd2441bc483f3811ee27a0c7b0 (patch)
tree2aa5156d0f75f9bac8a6603c519fd7087f288a6c /drivers/hwtracing/coresight
parentMerge 4.3-rc4 into char-misc-next (diff)
downloadlinux-497b59565b25d6dd2441bc483f3811ee27a0c7b0.tar.xz
linux-497b59565b25d6dd2441bc483f3811ee27a0c7b0.zip
Coresight: ETMv4: Prevent TRCRSCTLR0&1 from being accessed
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 <zhang.chunyan@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing/coresight')
-rw-r--r--drivers/hwtracing/coresight/coresight-etm4x.c22
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 254a81a4e6f4..a6707642bb23 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 * 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 * 2; i++)
drvdata->res_ctrl[i] = 0x0;
for (i = 0; i < drvdata->nr_ss_cmp; i++) {
@@ -1732,7 +1735,7 @@ 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 * 2)
return -EINVAL;
/*
@@ -2416,8 +2419,13 @@ static void etm4_init_arch_data(void *info)
drvdata->nr_addr_cmp = BMVAL(etmidr4, 0, 3);
/* NUMPC, bits[15:12] number of PE comparator inputs for tracing */
drvdata->nr_pe_cmp = BMVAL(etmidr4, 12, 15);
- /* NUMRSPAIR, bits[19:16] the number of resource pairs for tracing */
- drvdata->nr_resource = BMVAL(etmidr4, 16, 19);
+ /*
+ * NUMRSPAIR, bits[19:16]
+ * 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.
+ */
+ drvdata->nr_resource = BMVAL(etmidr4, 16, 19) + 1;
/*
* NUMSSCC, bits[23:20] the number of single-shot
* comparator control for tracing
@@ -2504,6 +2512,8 @@ static void etm4_init_default_data(struct etmv4_drvdata *drvdata)
drvdata->cntr_val[i] = 0x0;
}
+ /* Resource selector pair 0 is always implemented and reserved */
+ drvdata->res_idx = 0x2;
for (i = 2; i < drvdata->nr_resource * 2; i++)
drvdata->res_ctrl[i] = 0x0;