diff mbox series

[v2] ACPICA: Add support for printing AML arguments when trace point enabled

Message ID 20250417031040.514460-1-superm1@kernel.org
State New
Headers show
Series [v2] ACPICA: Add support for printing AML arguments when trace point enabled | expand

Commit Message

Mario Limonciello April 17, 2025, 3:10 a.m. UTC 
From: Mario Limonciello <mario.limonciello@amd.com>

When debug level is set to `ACPI_LV_TRACE_POINT` method start and
exit are emitted into the debug logs. This can be useful to understand
call paths, however none of the arguments for the method calls are
populated even when turning up other debug levels.

This can be useful for BIOSes that contain debug strings to see those
strings. When `ACPI_LV_TRACE_POINT` is set also output all of the arguments
for a given method call.

This enables this type of debugging:

```
extrace-0138 ex_trace_point        : Method Begin [0x0000000096b240c4:\M460] execution.
extrace-0173 ex_trace_args         :  "  POST CODE: %X  ACPI TIMER: %X  TIME: %d.%d ms\n", b0003f53, 1a26a8b2, 0, 15e, 0, 0
extrace-0138 ex_trace_point        : Method End [0x0000000096b240c4:\M460] execution.
```

Link: https://github.com/acpica/acpica/commit/08219d91b5678ae2fae6e4f208df790a4e108c1c
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
This is a backport from upstream ACPICA.  I'm not sure if there is a script
that converts code style, so I just manually adjusted to kernel code style.
It is really useful for me for debugging; so I would ideally like to see it
go for 6.16 if possible.

v2:
 * handle non-CONFIG_ACPI_DEBUG W=1 build
---
 drivers/acpi/acpica/acinterp.h |  3 ++
 drivers/acpi/acpica/dsmthdat.c |  1 +
 drivers/acpi/acpica/extrace.c  | 51 ++++++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+)
diff mbox series

Patch

diff --git a/drivers/acpi/acpica/acinterp.h b/drivers/acpi/acpica/acinterp.h
index 955114c926bd0..d02779ee92103 100644
--- a/drivers/acpi/acpica/acinterp.h
+++ b/drivers/acpi/acpica/acinterp.h
@@ -120,6 +120,9 @@  void
 acpi_ex_trace_point(acpi_trace_event_type type,
 		    u8 begin, u8 *aml, char *pathname);
 
+void
+acpi_ex_trace_args(union acpi_operand_object **params, u32 count);
+
 /*
  * exfield - ACPI AML (p-code) execution - field manipulation
  */
diff --git a/drivers/acpi/acpica/dsmthdat.c b/drivers/acpi/acpica/dsmthdat.c
index eca50517ad824..5393de4dbc4ca 100644
--- a/drivers/acpi/acpica/dsmthdat.c
+++ b/drivers/acpi/acpica/dsmthdat.c
@@ -188,6 +188,7 @@  acpi_ds_method_data_init_args(union acpi_operand_object **params,
 
 		index++;
 	}
+	acpi_ex_trace_args(params, index);
 
 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "%u args passed to method\n", index));
 	return_ACPI_STATUS(AE_OK);
diff --git a/drivers/acpi/acpica/extrace.c b/drivers/acpi/acpica/extrace.c
index b5e4bb4ae3ce6..e4721504c390d 100644
--- a/drivers/acpi/acpica/extrace.c
+++ b/drivers/acpi/acpica/extrace.c
@@ -147,6 +147,57 @@  acpi_ex_trace_point(acpi_trace_event_type type,
 	}
 }
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ex_trace_args
+ *
+ * PARAMETERS:  params            - AML method arguments
+ *              count             - numer of method arguments
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Trace any arguments
+ *
+ ******************************************************************************/
+
+void
+acpi_ex_trace_args(union acpi_operand_object **params, u32 count)
+{
+	u32 i;
+
+	ACPI_FUNCTION_NAME(ex_trace_args);
+
+	for (i = 0; i < count; i++) {
+		union acpi_operand_object *obj_desc = params[i];
+
+		if (!i) {
+			ACPI_DEBUG_PRINT((ACPI_DB_TRACE_POINT, " "));
+		}
+
+		switch (obj_desc->common.type) {
+		case ACPI_TYPE_INTEGER:
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_TRACE_POINT, "%llx", obj_desc->integer.value));
+			break;
+		case ACPI_TYPE_STRING:
+			if (!obj_desc->string.length) {
+				ACPI_DEBUG_PRINT_RAW((ACPI_DB_TRACE_POINT, "NULL"));
+				continue;
+			}
+			if (ACPI_IS_DEBUG_ENABLED(ACPI_LV_TRACE_POINT, _COMPONENT))
+				acpi_ut_print_string(obj_desc->string.pointer, ACPI_UINT8_MAX);
+			break;
+		default:
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_TRACE_POINT, "Unknown"));
+			break;
+		}
+		if (i+1 == count) {
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_TRACE_POINT, "\n"));
+		} else {
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_TRACE_POINT, ", "));
+		}
+	}
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_start_trace_method