[PATCH v6 1/8] ethdev: support report register names and filter

[Jie Hai <haijie1@huawei.com>]

This patch adds "filter" and "names" fields to "rte_dev_reg_info"
structure. Names of registers in data fields can be reported and
the registers can be filtered by their module names.

The new API rte_eth_dev_get_reg_info_ext() is added to support
reporting names and filtering by modules. And the original API
rte_eth_dev_get_reg_info() does not use the names and filter fields.
A local variable is used in rte_eth_dev_get_reg_info for
compatibility. If the drivers does not report the names, set them
to "index_XXX", which means the location in the register table.

Signed-off-by: Jie Hai <haijie1@huawei.com>
Acked-by: Huisong Li <lihuisong@huawei.com>
Acked-by: Chengwen Feng <fengchengwen@huawei.com>
---
 doc/guides/rel_notes/release_24_07.rst |  8 ++++++
 lib/ethdev/ethdev_trace.h              |  2 ++
 lib/ethdev/rte_dev_info.h              | 11 ++++++++
 lib/ethdev/rte_ethdev.c                | 38 ++++++++++++++++++++++++++
 lib/ethdev/rte_ethdev.h                | 29 ++++++++++++++++++++
 lib/ethdev/version.map                 |  3 ++
 6 files changed, 91 insertions(+)

diff --git a/doc/guides/rel_notes/release_24_07.rst b/doc/guides/rel_notes/release_24_07.rst
index 058609b0f36b..b0bb49c8f29e 100644
--- a/doc/guides/rel_notes/release_24_07.rst
+++ b/doc/guides/rel_notes/release_24_07.rst
@@ -186,6 +186,12 @@ New Features
   * Added defer queue reclamation via RCU.
   * Added SVE support for bulk lookup.
 
+* **Added support for dumping registers with names and filtering by modules.**
+
+  * Added new API functions ``rte_eth_dev_get_reg_info_ext()`` to filter the
+    registers by module names and get the information (names, values and other
+    attributes) of the filtered registers.
+
 
 Removed Items
 -------------
@@ -241,6 +247,8 @@ ABI Changes
    This section is a comment. Do not overwrite or remove it.
    Also, make sure to start the actual text at the margin.
    =======================================================
+   * ethdev: Added ``filter`` and ``names`` fields to ``rte_dev_reg_info``
+     structure for filtering by modules and reporting names of registers.
 
 * No ABI change that would break compatibility with 23.11.
 
diff --git a/lib/ethdev/ethdev_trace.h b/lib/ethdev/ethdev_trace.h
index 3bec87bfdb70..0c4780a09ef5 100644
--- a/lib/ethdev/ethdev_trace.h
+++ b/lib/ethdev/ethdev_trace.h
@@ -1152,6 +1152,8 @@ RTE_TRACE_POINT(
 	rte_trace_point_emit_u32(info->length);
 	rte_trace_point_emit_u32(info->width);
 	rte_trace_point_emit_u32(info->version);
+	rte_trace_point_emit_ptr(info->names);
+	rte_trace_point_emit_ptr(info->filter);
 	rte_trace_point_emit_int(ret);
 )
 
diff --git a/lib/ethdev/rte_dev_info.h b/lib/ethdev/rte_dev_info.h
index 67cf0ae52668..26b777f9836e 100644
--- a/lib/ethdev/rte_dev_info.h
+++ b/lib/ethdev/rte_dev_info.h
@@ -11,6 +11,11 @@ extern "C" {
 
 #include <stdint.h>
 
+#define RTE_ETH_REG_NAME_SIZE 64
+struct rte_eth_reg_name {
+	char name[RTE_ETH_REG_NAME_SIZE];
+};
+
 /*
  * Placeholder for accessing device registers
  */
@@ -20,6 +25,12 @@ struct rte_dev_reg_info {
 	uint32_t length; /**< Number of registers to fetch */
 	uint32_t width; /**< Size of device register */
 	uint32_t version; /**< Device version */
+	/**
+	 * Name of target module, filter for target subset of registers.
+	 * This field could affects register selection for data/length/names.
+	 */
+	const char *filter;
+	struct rte_eth_reg_name *names; /**< Registers name saver */
 };
 
 /*
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index f1c658f49e80..30ca4a0043c5 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -6388,8 +6388,37 @@ rte_eth_read_clock(uint16_t port_id, uint64_t *clock)
 
 int
 rte_eth_dev_get_reg_info(uint16_t port_id, struct rte_dev_reg_info *info)
+{
+	struct rte_dev_reg_info reg_info = { 0 };
+	int ret;
+
+	if (info == NULL) {
+		RTE_ETHDEV_LOG_LINE(ERR,
+			"Cannot get ethdev port %u register info to NULL",
+			port_id);
+		return -EINVAL;
+	}
+
+	reg_info.length = info->length;
+	reg_info.data = info->data;
+
+	ret = rte_eth_dev_get_reg_info_ext(port_id, &reg_info);
+	if (ret != 0)
+		return ret;
+
+	info->length = reg_info.length;
+	info->width = reg_info.width;
+	info->version = reg_info.version;
+	info->offset = reg_info.offset;
+
+	return 0;
+}
+
+int
+rte_eth_dev_get_reg_info_ext(uint16_t port_id, struct rte_dev_reg_info *info)
 {
 	struct rte_eth_dev *dev;
+	uint32_t i;
 	int ret;
 
 	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
@@ -6402,12 +6431,21 @@ rte_eth_dev_get_reg_info(uint16_t port_id, struct rte_dev_reg_info *info)
 		return -EINVAL;
 	}
 
+	if (info->names != NULL && info->length != 0)
+		memset(info->names, 0, sizeof(struct rte_eth_reg_name) * info->length);
+
 	if (*dev->dev_ops->get_reg == NULL)
 		return -ENOTSUP;
 	ret = eth_err(port_id, (*dev->dev_ops->get_reg)(dev, info));
 
 	rte_ethdev_trace_get_reg_info(port_id, info, ret);
 
+	/* Report the default names if drivers not report. */
+	if (ret == 0 && info->names != NULL && strlen(info->names[0].name) == 0) {
+		for (i = 0; i < info->length; i++)
+			snprintf(info->names[i].name, RTE_ETH_REG_NAME_SIZE,
+				"index_%u", info->offset + i);
+	}
 	return ret;
 }
 
diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index 548fada1c7ad..02cb3c07f742 100644
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -5071,6 +5071,35 @@ __rte_experimental
 int rte_eth_get_monitor_addr(uint16_t port_id, uint16_t queue_id,
 		struct rte_power_monitor_cond *pmc);
 
+/**
+ * Retrieve the filtered device registers (values and names) and
+ * register attributes (number of registers and register size)
+ *
+ * @param port_id
+ *   The port identifier of the Ethernet device.
+ * @param info
+ *   Pointer to rte_dev_reg_info structure to fill in.
+ *   - If info->filter is NULL, return info for all registers (seen as filter
+ *     none).
+ *   - If info->filter is not NULL, return error if the driver does not support
+ *     filter. Fill the length field with filtered register number.
+ *   - If info->data is NULL, the function fills in the width and length fields.
+ *   - If info->data is not NULL, ethdev considers there are enough spaces to
+ *     store the registers, and the values of registers with the filter string
+ *     as the module name are put into the buffer pointed at by info->data.
+ *   - If info->names is not NULL, drivers should fill it or the ethdev fills it
+ *     with default names.
+ * @return
+ *   - (0) if successful.
+ *   - (-ENOTSUP) if hardware doesn't support.
+ *   - (-EINVAL) if bad parameter.
+ *   - (-ENODEV) if *port_id* invalid.
+ *   - (-EIO) if device is removed.
+ *   - others depends on the specific operations implementation.
+ */
+__rte_experimental
+int rte_eth_dev_get_reg_info_ext(uint16_t port_id, struct rte_dev_reg_info *info);
+
 /**
  * Retrieve device registers and register attributes (number of registers and
  * register size)
diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
index 79f6f5293b5c..e3289e999382 100644
--- a/lib/ethdev/version.map
+++ b/lib/ethdev/version.map
@@ -325,6 +325,9 @@ EXPERIMENTAL {
 	rte_flow_template_table_resizable;
 	rte_flow_template_table_resize;
 	rte_flow_template_table_resize_complete;
+
+	# added in 24.07
+	rte_eth_dev_get_reg_info_ext;
 };
 
 INTERNAL {
-- 
2.33.0