[PATCH v3 13/26] coresight: etm4x: Add commentary on the registers

Suzuki K Poulose
2020-10-28T22:10:38Z

As we are about define a switch..case table for individual register
access by offset for implementing the system instruction support,
document the possible set of registers for each group to make
it easier to co-relate.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
drivers/hwtracing/coresight/coresight-etm4x.h | 21 ++++++++++++-------
1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index 14e0f29db6b3..510828c73db6 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -44,13 +44,13 @@
#define TRCVDSACCTLR 0x0A4
#define TRCVDARCCTLR 0x0A8
/* Derived resources registers */
-#define TRCSEQEVRn(n) (0x100 + (n * 4))
+#define TRCSEQEVRn(n) (0x100 + (n * 4)) /* n = 0-2 */
#define TRCSEQRSTEVR 0x118
#define TRCSEQSTR 0x11C
#define TRCEXTINSELR 0x120
-#define TRCCNTRLDVRn(n) (0x140 + (n * 4))
-#define TRCCNTCTLRn(n) (0x150 + (n * 4))
-#define TRCCNTVRn(n) (0x160 + (n * 4))
+#define TRCCNTRLDVRn(n) (0x140 + (n * 4)) /* n = 0-3 */
+#define TRCCNTCTLRn(n) (0x150 + (n * 4)) /* n = 0-3 */
+#define TRCCNTVRn(n) (0x160 + (n * 4)) /* n = 0-3 */
/* ID registers */
#define TRCIDR8 0x180
#define TRCIDR9 0x184
@@ -59,7 +59,7 @@
#define TRCIDR12 0x190
#define TRCIDR13 0x194
#define TRCIMSPEC0 0x1C0
-#define TRCIMSPECn(n) (0x1C0 + (n * 4))
+#define TRCIMSPECn(n) (0x1C0 + (n * 4)) /* n = 1-7 */
#define TRCIDR0 0x1E0
#define TRCIDR1 0x1E4
#define TRCIDR2 0x1E8
@@ -68,9 +68,12 @@
#define TRCIDR5 0x1F4
#define TRCIDR6 0x1F8
#define TRCIDR7 0x1FC
-/* Resource selection registers */
+/*
+ * Resource selection registers, n = 2-31.
+ * First pair (regs 0, 1) is always present and is reserved.
+ */
#define TRCRSCTLRn(n) (0x200 + (n * 4))
-/* Single-shot comparator registers */
+/* Single-shot comparator registers, n = 0-7 */
#define TRCSSCCRn(n) (0x280 + (n * 4))
#define TRCSSCSRn(n) (0x2A0 + (n * 4))
#define TRCSSPCICRn(n) (0x2C0 + (n * 4))
@@ -80,11 +83,13 @@
#define TRCPDCR 0x310
#define TRCPDSR 0x314
/* Trace registers (0x318-0xEFC) */
-/* Comparator registers */
+/* Address Comparator registers n = 0-15 */
#define TRCACVRn(n) (0x400 + (n * 8))
#define TRCACATRn(n) (0x480 + (n * 8))
+/* Data Value Comparator Value registers, n = 0-7 */
#define TRCDVCVRn(n) (0x500 + (n * 16))
#define TRCDVCMRn(n) (0x580 + (n * 16))
+/* ContextID/Virtual ContextID comparators, n = 0-7 */
#define TRCCIDCVRn(n) (0x600 + (n * 8))
#define TRCVMIDCVRn(n) (0x640 + (n * 8))
#define TRCCIDCCTLR0 0x680
--
2.24.1