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

From: Suzuki K Poulose
Date: Mon Jun 05 2023 - 09:30:49 EST


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@xxxxxxx
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: frowand.list@xxxxxxxxx
Cc: linux@xxxxxxxxxxxxxxx
Cc: Mike Leach <mike.leach@xxxxxxxxxx>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
.../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