From: Anup Patel <anup.patel@oss.qualcomm.com>
To: Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>,
Palmer Dabbelt <palmer@dabbelt.com>,
Paul Walmsley <pjw@kernel.org>,
Greg KH <gregkh@linuxfoundation.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Ian Rogers <irogers@google.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Namhyung Kim <namhyung@kernel.org>,
Mark Rutland <mark.rutland@arm.com>, Jiri Olsa <jolsa@kernel.org>,
Adrian Hunter <adrian.hunter@intel.com>,
Liang Kan <kan.liang@linux.intel.com>,
Mayuresh Chitale <mchitale@gmail.com>,
Anup Patel <anup@brainfault.org>,
Atish Patra <atish.patra@linux.dev>,
Andrew Jones <andrew.jones@oss.qualcomm.com>,
Sunil V L <sunilvl@oss.qualcomm.com>,
linux-riscv@lists.infradead.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org,
Mayuresh Chitale <mayuresh.chitale@oss.qualcomm.com>,
Anup Patel <anup.patel@oss.qualcomm.com>
Subject: [PATCH v3 05/12] rvtrace: Add trace encoder driver
Date: Wed, 25 Feb 2026 11:54:41 +0530 [thread overview]
Message-ID: <20260225062448.4027948-6-anup.patel@oss.qualcomm.com> (raw)
In-Reply-To: <20260225062448.4027948-1-anup.patel@oss.qualcomm.com>
From: Mayuresh Chitale <mayuresh.chitale@oss.qualcomm.com>
Add initial implementation of RISC-V trace encoder driver. The encoder
is defined in the RISC-V Trace Control Interface specification.
Co-developed-by: Anup Patel <anup.patel@oss.qualcomm.com>
Signed-off-by: Anup Patel <anup.patel@oss.qualcomm.com>
Signed-off-by: Mayuresh Chitale <mayuresh.chitale@oss.qualcomm.com>
---
drivers/hwtracing/rvtrace/Kconfig | 7 ++
drivers/hwtracing/rvtrace/Makefile | 1 +
drivers/hwtracing/rvtrace/rvtrace-encoder.c | 130 ++++++++++++++++++++
3 files changed, 138 insertions(+)
create mode 100644 drivers/hwtracing/rvtrace/rvtrace-encoder.c
diff --git a/drivers/hwtracing/rvtrace/Kconfig b/drivers/hwtracing/rvtrace/Kconfig
index f8f6feea1953..ba35c05f3f54 100644
--- a/drivers/hwtracing/rvtrace/Kconfig
+++ b/drivers/hwtracing/rvtrace/Kconfig
@@ -14,3 +14,10 @@ menuconfig RVTRACE
To compile this driver as a module, choose M here: the module
will be called rvtrace.
+
+config RVTRACE_ENCODER
+ tristate "RISC-V Trace Encoder driver"
+ depends on RVTRACE
+ default y
+ help
+ This driver provides support for RISC-V Trace Encoder component.
diff --git a/drivers/hwtracing/rvtrace/Makefile b/drivers/hwtracing/rvtrace/Makefile
index 988525a379cf..f320693a1fc5 100644
--- a/drivers/hwtracing/rvtrace/Makefile
+++ b/drivers/hwtracing/rvtrace/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_RVTRACE) += rvtrace.o
rvtrace-y := rvtrace-core.o rvtrace-platform.o
+obj-$(CONFIG_RVTRACE_ENCODER) += rvtrace-encoder.o
diff --git a/drivers/hwtracing/rvtrace/rvtrace-encoder.c b/drivers/hwtracing/rvtrace/rvtrace-encoder.c
new file mode 100644
index 000000000000..d189819aecf7
--- /dev/null
+++ b/drivers/hwtracing/rvtrace/rvtrace-encoder.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2026 Qualcomm Technologies, Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/rvtrace.h>
+#include <linux/types.h>
+
+#define RVTRACE_COMPONENT_CTRL_ITRACE_SHIFT 2
+#define RVTRACE_COMPONENT_CTRL_INSTMODE_SHIFT 4
+#define RVTRACE_COMPONENT_CTRL_INSTMODE_OPIT 0x6
+
+static int rvtrace_encoder_start(struct rvtrace_component *comp)
+{
+ int ret;
+ u32 val;
+
+ val = rvtrace_read32(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET);
+ val |= BIT(RVTRACE_COMPONENT_CTRL_ENABLE_SHIFT);
+ rvtrace_write32(comp->pdata, val, RVTRACE_COMPONENT_CTRL_OFFSET);
+ ret = rvtrace_poll_bit(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET,
+ RVTRACE_COMPONENT_CTRL_ENABLE_SHIFT, 1,
+ comp->pdata->control_poll_timeout_usecs);
+ if (ret) {
+ dev_err(&comp->dev, "failed to enable encoder.\n");
+ return ret;
+ }
+
+ /* set mode */
+ val = rvtrace_read32(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET);
+ val |= (RVTRACE_COMPONENT_CTRL_INSTMODE_OPIT << RVTRACE_COMPONENT_CTRL_INSTMODE_SHIFT);
+ rvtrace_write32(comp->pdata, val, RVTRACE_COMPONENT_CTRL_OFFSET);
+
+ val = rvtrace_read32(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET);
+ val |= BIT(RVTRACE_COMPONENT_CTRL_ITRACE_SHIFT);
+ rvtrace_write32(comp->pdata, val, RVTRACE_COMPONENT_CTRL_OFFSET);
+ ret = rvtrace_poll_bit(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET,
+ RVTRACE_COMPONENT_CTRL_ITRACE_SHIFT, 1,
+ comp->pdata->control_poll_timeout_usecs);
+ if (ret)
+ dev_err(&comp->dev, "failed to enable tracing.\n");
+
+ return ret;
+}
+
+static int rvtrace_encoder_stop(struct rvtrace_component *comp)
+{
+ int ret;
+ u32 val;
+
+ val = rvtrace_read32(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET);
+ val &= ~BIT(RVTRACE_COMPONENT_CTRL_ITRACE_SHIFT);
+ rvtrace_write32(comp->pdata, val, RVTRACE_COMPONENT_CTRL_OFFSET);
+ ret = rvtrace_poll_bit(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET,
+ RVTRACE_COMPONENT_CTRL_ITRACE_SHIFT, 0,
+ comp->pdata->control_poll_timeout_usecs);
+ if (ret) {
+ dev_err(&comp->dev, "failed to stop tracing.\n");
+ return ret;
+ }
+
+ val = rvtrace_read32(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET);
+ val &= ~BIT(RVTRACE_COMPONENT_CTRL_ENABLE_SHIFT);
+ rvtrace_write32(comp->pdata, val, RVTRACE_COMPONENT_CTRL_OFFSET);
+ ret = rvtrace_poll_bit(comp->pdata, RVTRACE_COMPONENT_CTRL_OFFSET,
+ RVTRACE_COMPONENT_CTRL_ENABLE_SHIFT, 0,
+ comp->pdata->control_poll_timeout_usecs);
+ if (ret) {
+ dev_err(&comp->dev, "failed to disable encoder.\n");
+ return ret;
+ }
+
+ return rvtrace_comp_poll_empty(comp);
+}
+
+static int rvtrace_encoder_probe(struct rvtrace_component *comp)
+{
+ int ret;
+
+ ret = rvtrace_enable_component(comp->pdata);
+ if (ret)
+ return dev_err_probe(&comp->dev, ret, "failed to enable encoder.\n");
+
+ return 0;
+}
+
+static void rvtrace_encoder_remove(struct rvtrace_component *comp)
+{
+ int ret;
+
+ ret = rvtrace_disable_component(comp->pdata);
+ if (ret)
+ dev_err(&comp->dev, "failed to disable encoder.\n");
+}
+
+static struct rvtrace_component_id rvtrace_encoder_ids[] = {
+ { .type = RVTRACE_COMPONENT_TYPE_ENCODER,
+ .version = rvtrace_component_mkversion(1, 0), },
+ {},
+};
+
+static struct rvtrace_driver rvtrace_encoder_driver = {
+ .id_table = rvtrace_encoder_ids,
+ .start = rvtrace_encoder_start,
+ .stop = rvtrace_encoder_stop,
+ .probe = rvtrace_encoder_probe,
+ .remove = rvtrace_encoder_remove,
+ .driver = {
+ .name = "rvtrace-encoder",
+ },
+};
+
+static int __init rvtrace_encoder_init(void)
+{
+ return rvtrace_register_driver(&rvtrace_encoder_driver);
+}
+
+static void __exit rvtrace_encoder_exit(void)
+{
+ rvtrace_unregister_driver(&rvtrace_encoder_driver);
+}
+
+module_init(rvtrace_encoder_init);
+module_exit(rvtrace_encoder_exit);
+
+/* Module information */
+MODULE_AUTHOR("Mayuresh Chitale");
+MODULE_DESCRIPTION("RISC-V Trace Encoder Driver");
+MODULE_LICENSE("GPL");
--
2.43.0
next prev parent reply other threads:[~2026-02-25 6:25 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-25 6:24 [PATCH v3 00/12] Linux RISC-V trace framework and drivers Anup Patel
2026-02-25 6:24 ` [PATCH v3 01/12] dt-bindings: Add RISC-V trace component bindings Anup Patel
2026-02-25 6:24 ` [PATCH v3 02/12] rvtrace: Initial implementation of driver framework Anup Patel
2026-02-25 6:24 ` [PATCH v3 03/12] rvtrace: Add functions to create/destroy a trace component path Anup Patel
2026-02-25 6:24 ` [PATCH v3 04/12] rvtrace: Add functions to start/stop tracing on a " Anup Patel
2026-02-25 6:24 ` Anup Patel [this message]
2026-02-25 6:24 ` [PATCH v3 06/12] rvtrace: Add function to copy into perf AUX buffer Anup Patel
2026-02-25 6:24 ` [PATCH v3 07/12] rvtrace: Add trace ramsink driver Anup Patel
2026-04-16 10:14 ` Eric Lin
2026-04-21 11:30 ` Mayuresh Chitale
2026-04-27 12:25 ` Mayuresh Chitale
2026-02-25 6:24 ` [PATCH v3 08/12] riscv: Enable DMA_RESTRICTED_POOL in defconfig Anup Patel
2026-02-25 6:24 ` [PATCH v3 09/12] rvtrace: Add perf driver for tracing using perf tool Anup Patel
2026-02-25 6:24 ` [PATCH v3 10/12] perf tools: Add RISC-V trace PMU record capabilities Anup Patel
2026-02-25 6:24 ` [PATCH v3 11/12] perf tools: Initial support for RISC-V trace decoder Anup Patel
2026-02-25 6:24 ` [PATCH v3 12/12] MAINTAINERS: Add entry for RISC-V trace framework Anup Patel
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