[PATCH 3/5] drm/komeda: Optionally dump DRM state on interrupts

From: Mihail Atanassov
Date: Mon Oct 21 2019 - 12:47:46 EST


It's potentially useful information when diagnosing error/warn IRQs, so
dump it to dmesg with a drm_info_printer. Hide this extra debug dumping
behind another komeda_dev->err_verbosity bit.

Note that there's not much sense in dumping it for INFO events,
since the VSYNC event will swamp the log.

Signed-off-by: Mihail Atanassov <mihail.atanassov@xxxxxxx>
---
drivers/gpu/drm/arm/display/komeda/komeda_dev.h | 5 ++++-
drivers/gpu/drm/arm/display/komeda/komeda_event.c | 8 +++++++-
2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
index 831c375180f8..4809000c1efb 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
@@ -205,11 +205,14 @@ struct komeda_dev {
/**
* @err_verbosity: bitmask for how much extra info to print on error
*
- * See KOMEDA_DEV_* macros for details.
+ * See KOMEDA_DEV_* macros for details. Low byte contains the debug
+ * level categories, the high byte contains extra debug options.
*/
u16 err_verbosity;
/* Print a single line per error per frame with error events. */
#define KOMEDA_DEV_PRINT_ERR_EVENTS BIT(0)
+ /* Dump DRM state on an error or warning event. */
+#define KOMEDA_DEV_PRINT_DUMP_STATE_ON_EVENT BIT(8)
};

static inline bool
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_event.c b/drivers/gpu/drm/arm/display/komeda/komeda_event.c
index 575ed4df74ed..5da61e7d75d5 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_event.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_event.c
@@ -4,6 +4,7 @@
* Author: James.Qian.Wang <james.qian.wang@xxxxxxx>
*
*/
+#include <drm/drm_atomic.h>
#include <drm/drm_print.h>

#include "komeda_dev.h"
@@ -113,6 +114,7 @@ void komeda_print_events(struct komeda_events *evts, struct drm_device *dev)
static bool en_print = true;
struct komeda_dev *mdev = dev->dev_private;
u16 const err_verbosity = mdev->err_verbosity;
+ u64 evts_mask = evts->global | evts->pipes[0] | evts->pipes[1];

/* reduce the same msg print, only print the first evt for one frame */
if (evts->global || is_new_frame(evts))
@@ -123,9 +125,10 @@ void komeda_print_events(struct komeda_events *evts, struct drm_device *dev)
if (err_verbosity & KOMEDA_DEV_PRINT_ERR_EVENTS)
print_evts |= KOMEDA_ERR_EVENTS;

- if ((evts->global | evts->pipes[0] | evts->pipes[1]) & print_evts) {
+ if (evts_mask & print_evts) {
char msg[256];
struct komeda_str str;
+ struct drm_printer p = drm_info_printer(dev->dev);

str.str = msg;
str.sz = sizeof(msg);
@@ -139,6 +142,9 @@ void komeda_print_events(struct komeda_events *evts, struct drm_device *dev)
evt_str(&str, evts->pipes[1]);

DRM_ERROR("err detect: %s\n", msg);
+ if ((err_verbosity & KOMEDA_DEV_PRINT_DUMP_STATE_ON_EVENT)
+ && (evts_mask & (KOMEDA_ERR_EVENTS | KOMEDA_WARN_EVENTS)))
+ drm_state_dump(dev, &p);

en_print = false;
}
--
2.23.0