[PATCH v2] Coresight: ETMv4: Prevent TRCRSCTLR0&1 from being accessed
Chunyan Zhang
zhang.chunyan at linaro.org
Thu Aug 27 21:10:01 PDT 2015
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 at linaro.org>
---
drivers/hwtracing/coresight/coresight-etm4x.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 1312e99..fe93b47 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++) {
@@ -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 * 2)
return -EINVAL;
/*
@@ -2410,8 +2413,8 @@ 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 minus one */
+ drvdata->nr_resource = BMVAL(etmidr4, 16, 19) + 1;
/*
* NUMSSCC, bits[23:20] the number of single-shot
* comparator control for tracing
@@ -2498,6 +2501,8 @@ 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;
--
1.9.1
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