Re: [PATCH v1 1/3] Coresight: Add driver to support for CSR

From: Trilok Soni
Date: Tue May 30 2023 - 15:21:32 EST


On 5/26/2023 8:35 AM, Mao Jinlong wrote:
This driver provides support for CoreSight Slave Register block
that hosts miscellaneous configuration registers. Those
configuration registers can be used to control, various coresight
configurations.

Signed-off-by: Hao Zhang <quic_hazha@xxxxxxxxxxx>
Signed-off-by: Mao Jinlong <quic_jinlmao@xxxxxxxxxxx>
---
drivers/hwtracing/coresight/Kconfig | 12 ++
drivers/hwtracing/coresight/Makefile | 1 +
drivers/hwtracing/coresight/coresight-csr.c | 142 ++++++++++++++++++++
drivers/hwtracing/coresight/coresight-csr.h | 54 ++++++++
4 files changed, 209 insertions(+)
create mode 100644 drivers/hwtracing/coresight/coresight-csr.c
create mode 100644 drivers/hwtracing/coresight/coresight-csr.h

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 2b5bbfffbc4f..e769ea3709d9 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -236,4 +236,16 @@ config CORESIGHT_TPDA
To compile this driver as a module, choose M here: the module will be
called coresight-tpda.
+
+config CORESIGHT_CSR
+ tristate "CoreSight Slave Register driver"
+ help
+ This driver provides support for CoreSight Slave Register block
+ that hosts miscellaneous configuration registers.
+ Those configuration registers can be used to control, various
+ coresight configurations.
+
+ To compile this driver as a module, choose M here: the module will be
+ called coresight-csr.
+
endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 33bcc3f7b8ae..956c642d05f6 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -30,3 +30,4 @@ obj-$(CONFIG_CORESIGHT_TPDA) += coresight-tpda.o
coresight-cti-y := coresight-cti-core.o coresight-cti-platform.o \
coresight-cti-sysfs.o
obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o
+obj-$(CONFIG_CORESIGHT_CSR) += coresight-csr.o
diff --git a/drivers/hwtracing/coresight/coresight-csr.c b/drivers/hwtracing/coresight/coresight-csr.c
new file mode 100644
index 000000000000..a1403e8531ee
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-csr.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#include "coresight-priv.h"
+#include "coresight-csr.h"
+
+DEFINE_CORESIGHT_DEVLIST(csr_devs, "csr");
+
+static LIST_HEAD(csr_list);
+
+/*
+ * Get the CSR by name.
+ */
+struct coresight_csr *coresight_csr_get(const char *name)
+{
+ struct coresight_csr *csr;
+
+ list_for_each_entry(csr, &csr_list, link) {
+ if (!strcmp(csr->name, name))
+ return csr;
+ }
+ return ERR_PTR(-EINVAL);
+}
+EXPORT_SYMBOL(coresight_csr_get);

EXPORT_SYMBOL_GPL everywhere in this driver please.

+
+/*
+ * Get the device node's name from device tree.
+ */
+int of_get_coresight_csr_name(struct device_node *node, const char **csr_name)
+{
+ struct device_node *csr_node;
+
+ csr_node = of_parse_phandle(node, "coresight-csr", 0);
+ if (!csr_node)
+ return -EINVAL;
+
+ *csr_name = csr_node->full_name;
+ of_node_put(csr_node);
+ return 0;
+}
+EXPORT_SYMBOL(of_get_coresight_csr_name);

---Trilok Soni