drm: POC drm on dyndbg - use in core, 2 helpers, 3 drivers.

Use DECLARE_DYNDBG_CLASSMAP across DRM:

 - in .c files, since macro defines/initializes a record

 - in drivers, $mod_{drv,drm,param}.c
   ie where param setup is done, since a classmap is param related

 - in drm/drm_print.c
   since existing __drm_debug param is defined there,
   and we ifdef it, and provide an elaborated alternative.

 - in drm_*_helper modules:
   dp/drm_dp - 1st item in makefile target
   drivers/gpu/drm/drm_crtc_helper.c - random pick iirc.

Since these modules all use identical CLASSMAP declarations (ie: names
and .class_id's) they will all respond together to "class DRM_UT_*"
query-commands:

  :#> echo class DRM_UT_KMS +p > /proc/dynamic_debug/control

NOTES:

This changes __drm_debug from int to ulong, so BIT() is usable on it.

DRM's enum drm_debug_category values need to sync with the index of
their respective class-names here.  Then .class_id == category, and
dyndbg's class FOO mechanisms will enable drm_dbg(DRM_UT_KMS, ...).

Though DRM needs consistent categories across all modules, thats not
generally needed; modules X and Y could define FOO differently (ie a
different NAME => class_id mapping), changes are made according to
each module's private class-map.

No callsites are actually selected by this patch, since none are
class'd yet.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20220912052852.1123868-3-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c

@@ -38,6 +38,8 @@
 #include <linux/mmu_notifier.h>
 #include <linux/suspend.h>
 #include <linux/cc_platform.h>
+#include <linux/fb.h>
+#include <linux/dynamic_debug.h>
 
 #include "amdgpu.h"
 #include "amdgpu_irq.h"
@@ -185,6 +187,18 @@ int amdgpu_vcnfw_log;
 
 static void amdgpu_drv_delayed_reset_work_handler(struct work_struct *work);
 
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
 struct amdgpu_mgpu_info mgpu_info = {
 	.mutex = __MUTEX_INITIALIZER(mgpu_info.mutex),
 	.delayed_reset_work = __DELAYED_WORK_INITIALIZER(

drivers/gpu/drm/display/drm_dp_helper.c

@@ -30,6 +30,7 @@
 #include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/string_helpers.h>
+#include <linux/dynamic_debug.h>
 
 #include <drm/display/drm_dp_helper.h>
 #include <drm/display/drm_dp_mst_helper.h>
@@ -40,6 +41,18 @@
 
 #include "drm_dp_helper_internal.h"
 
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
 struct dp_aux_backlight {
 	struct backlight_device *base;
 	struct drm_dp_aux *aux;

drivers/gpu/drm/drm_crtc_helper.c

@@ -32,6 +32,7 @@
 #include <linux/export.h>
 #include <linux/kernel.h>
 #include <linux/moduleparam.h>
+#include <linux/dynamic_debug.h>
 
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
@@ -51,6 +52,18 @@
 
 #include "drm_crtc_helper_internal.h"
 
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
 /**
  * DOC: overview
  *

drivers/gpu/drm/drm_print.c

@@ -40,7 +40,7 @@
  * __drm_debug: Enable debug output.
  * Bitmask of DRM_UT_x. See include/drm/drm_print.h for details.
  */
-unsigned int __drm_debug;
+unsigned long __drm_debug;
 EXPORT_SYMBOL(__drm_debug);
 
 MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug category.\n"
@@ -52,7 +52,30 @@ MODULE_PARM_DESC(debug, "Enable debug output, where each bit enables a debug cat
 "\t\tBit 5 (0x20)  will enable VBL messages (vblank code)\n"
 "\t\tBit 7 (0x80)  will enable LEASE messages (leasing code)\n"
 "\t\tBit 8 (0x100) will enable DP messages (displayport code)");
-module_param_named(debug, __drm_debug, int, 0600);
+
+#if !defined(CONFIG_DRM_USE_DYNAMIC_DEBUG)
+module_param_named(debug, __drm_debug, ulong, 0600);
+#else
+/* classnames must match vals of enum drm_debug_category */
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
+static struct ddebug_class_param drm_debug_bitmap = {
+	.bits = &__drm_debug,
+	.flags = "p",
+	.map = &drm_debug_classes,
+};
+module_param_cb(debug, &param_ops_dyndbg_classes, &drm_debug_bitmap, 0600);
+#endif
 
 void __drm_puts_coredump(struct drm_printer *p, const char *str)
 {

drivers/gpu/drm/i915/i915_params.c

@@ -29,6 +29,18 @@
 #include "i915_params.h"
 #include "i915_drv.h"
 
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
 #define i915_param_named(name, T, perm, desc) \
 	module_param_named(name, i915_modparams.name, T, perm); \
 	MODULE_PARM_DESC(name, desc)

drivers/gpu/drm/nouveau/nouveau_drm.c

@@ -28,6 +28,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/vga_switcheroo.h>
 #include <linux/mmu_notifier.h>
+#include <linux/dynamic_debug.h>
 
 #include <drm/drm_aperture.h>
 #include <drm/drm_crtc_helper.h>
@@ -70,6 +71,18 @@
 #include "nouveau_svm.h"
 #include "nouveau_dmem.h"
 
+DECLARE_DYNDBG_CLASSMAP(drm_debug_classes, DD_CLASS_TYPE_DISJOINT_BITS, 0,
+			"DRM_UT_CORE",
+			"DRM_UT_DRIVER",
+			"DRM_UT_KMS",
+			"DRM_UT_PRIME",
+			"DRM_UT_ATOMIC",
+			"DRM_UT_VBL",
+			"DRM_UT_STATE",
+			"DRM_UT_LEASE",
+			"DRM_UT_DP",
+			"DRM_UT_DRMRES");
+
 MODULE_PARM_DESC(config, "option string to pass to driver core");
 static char *nouveau_config;
 module_param_named(config, nouveau_config, charp, 0400);

include/drm/drm_print.h

@@ -35,7 +35,7 @@
 #include <drm/drm.h>
 
 /* Do *not* use outside of drm_print.[ch]! */
-extern unsigned int __drm_debug;
+extern unsigned long __drm_debug;
 
 /**
  * DOC: print
@@ -275,6 +275,7 @@ static inline struct drm_printer drm_err_printer(const char *prefix)
  *
  */
 enum drm_debug_category {
+	/* These names must match those in DYNAMIC_DEBUG_CLASSBITS */
 	/**
 	 * @DRM_UT_CORE: Used in the generic drm code: drm_ioctl.c, drm_mm.c,
 	 * drm_memory.c, ...