[PATCH] coresight: etm4x: Match all ETM4 instances based on DEVARCH and DEVTYPE

Suzuki K Poulose suzuki.poulose at arm.com
Mon Jun 5 06:30:30 PDT 2023


Instead of adding the PIDs forever to the list for the new CPUs, let us detect
a component to be ETMv4 based on the CoreSight CID, DEVTYPE=PE_TRACE and
DEVARCH=ETMv4. This is already done for some of the ETMs. We can extend the PID
matching to match the PIDR2:JEDEC, BIT[3], which must be 1 (RA0) always.

Link: https://lkml.kernel.org/r/20230317030501.1811905-1-anshuman.khandual@arm.com
Cc: Anshuman Khandual <anshuman.khandual at arm.com>
Cc: Rob Herring <robh+dt at kernel.org>
Cc: frowand.list at gmail.com
Cc: linux at armlinux.org.uk
Cc: Mike Leach <mike.leach at linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
 .../coresight/coresight-etm4x-core.c          |  5 +++++
 drivers/hwtracing/coresight/coresight-priv.h  | 19 +++++++++++++++++--
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 4c15fae534f3..8a2e24d5686a 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -2260,6 +2260,11 @@ static const struct amba_id etm4_ids[] = {
 	CS_AMBA_UCI_ID(0x000cc0af, uci_id_etm4),/* Marvell ThunderX2 */
 	CS_AMBA_UCI_ID(0x000b6d01, uci_id_etm4),/* HiSilicon-Hip08 */
 	CS_AMBA_UCI_ID(0x000b6d02, uci_id_etm4),/* HiSilicon-Hip09 */
+	/*
+	 * Match all PIDs with ETM4 DEVARCH. No need for adding any of the new
+	 * CPUs to the list here.
+	 */
+	CS_AMBA_MATCH_ALL_UCI(uci_id_etm4),
 	{},
 };
 
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index 595ce5862056..72ec36c9232c 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -193,12 +193,27 @@ extern void coresight_remove_cti_ops(void);
 	}
 
 /* coresight AMBA ID, full UCI structure: id table entry. */
-#define CS_AMBA_UCI_ID(pid, uci_ptr)		\
+#define __CS_AMBA_UCI_ID(pid, m, uci_ptr)	\
 	{					\
 		.id	= pid,			\
-		.mask	= 0x000fffff,		\
+		.mask	= m,			\
 		.data	= (void *)uci_ptr	\
 	}
+#define CS_AMBA_UCI_ID(pid, uci)	__CS_AMBA_UCI_ID(pid, 0x000fffff, uci)
+/*
+ * PIDR2[JEDEC], BIT(3) must be 1 (Read As One) to indicate that rest of the
+ * PIDR1, PIDR2 DES_* fields follow JEDEC encoding for the designer. Use that
+ * as a match value for blanket matching all devices in the given CoreSight
+ * device type and architecture.
+ */
+#define PIDR2_JEDEC			BIT(3)
+#define PID_PIDR2_JEDEC			(PIDR2_JEDEC << 16)
+/*
+ * Match all PIDs in a given CoreSight device type and architecture, defined
+ * by the uci.
+ */
+#define CS_AMBA_MATCH_ALL_UCI(uci)					\
+	__CS_AMBA_UCI_ID(PID_PIDR2_JEDEC, PID_PIDR2_JEDEC, uci)
 
 /* extract the data value from a UCI structure given amba_id pointer. */
 static inline void *coresight_get_uci_data(const struct amba_id *id)
-- 
2.34.1




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