Signed-off-by: Thomas Zimmermann <[email protected]>
---
MAINTAINERS | 3 +-
.../amd/display/amdgpu_dm/amdgpu_dm_plane.c | 2 +
drivers/gpu/drm/ast/ast_mode.c | 2 +
drivers/gpu/drm/drm_panic.c | 78 ++++++++++---------
drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 2 +
drivers/gpu/drm/i915/display/i9xx_plane.c | 3 +
.../drm/i915/display/skl_universal_plane.c | 4 +
drivers/gpu/drm/imx/ipuv3/ipuv3-plane.c | 2 +
drivers/gpu/drm/mgag200/mgag200_drv.h | 4 +-
drivers/gpu/drm/nouveau/dispnv50/wndw.c | 2 +
.../gpu/drm/renesas/rcar-du/rcar_du_plane.c | 2 +
.../drm/renesas/shmobile/shmob_drm_plane.c | 2 +
drivers/gpu/drm/sysfb/drm_sysfb_helper.h | 4 +-
drivers/gpu/drm/sysfb/vesadrm.c | 1 +
drivers/gpu/drm/tidss/tidss_plane.c | 2 +
drivers/gpu/drm/tiny/bochs.c | 4 +-
drivers/gpu/drm/virtio/virtgpu_plane.c | 2 +
include/drm/drm_mode_config.h | 4 +-
include/drm/drm_modeset_helper_vtables.h | 11 ++-
include/drm/drm_panic.h | 49 +++---------
include/drm/drm_panic_helper.h | 27 +++++++
include/drm/drm_plane.h | 57 ++++++++++++++
22 files changed, 180 insertions(+), 87 deletions(-)
create mode 100644 include/drm/drm_panic_helper.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 928b3ba23a76..472c5c48729d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9020,7 +9020,8 @@ F: drivers/gpu/drm/drm_draw.c
F: drivers/gpu/drm/drm_draw_internal.h
F: drivers/gpu/drm/drm_panic*.c
F: drivers/gpu/drm/tests/drm_panic_test.c
-F: include/drm/drm_panic*
+F: include/drm/drm_panic.h
+F: include/drm/drm_panic_helper.h
DRM PANIC QR CODE
M: Jocelyn Falempe <[email protected]>
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
index 824ef3ce5de0..eadc22a255bb 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c
@@ -28,6 +28,7 @@
#include <drm/drm_blend.h>
#include "drm/drm_framebuffer.h"
#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_fourcc.h>
@@ -2177,6 +2178,7 @@ static const struct drm_plane_funcs dm_plane_funcs = {
.atomic_set_property = dm_atomic_plane_set_property,
.atomic_get_property = dm_atomic_plane_get_property,
#endif
+ DRM_PANIC_PLANE_FUNCS,
};
int amdgpu_dm_plane_init(struct amdgpu_display_manager *dm,
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index d5ed8c5c7925..ceebf9421100 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -43,6 +43,7 @@
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
@@ -652,6 +653,7 @@ static const struct drm_plane_funcs ast_primary_plane_funcs = {
.disable_plane = drm_atomic_helper_disable_plane,
.destroy = drm_plane_cleanup,
DRM_GEM_SHADOW_PLANE_FUNCS,
+ DRM_PANIC_PLANE_FUNCS,
};
static int ast_primary_plane_init(struct ast_device *ast)
diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
index 2263a11efdf6..2ecb4d1f6d47 100644
--- a/drivers/gpu/drm/drm_panic.c
+++ b/drivers/gpu/drm/drm_panic.c
@@ -28,6 +28,7 @@
#include <drm/drm_framebuffer.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_plane.h>
#include <drm/drm_print.h>
#include <drm/drm_rect.h>
@@ -42,32 +43,18 @@ MODULE_LICENSE("GPL");
/**
* DOC: overview
*
- * To enable DRM panic for a driver, the primary plane must implement a
- * &drm_plane_helper_funcs.get_scanout_buffer helper function. It is then
- * automatically registered to the drm panic handler.
- * When a panic occurs, the &drm_plane_helper_funcs.get_scanout_buffer will be
- * called, and the driver can provide a framebuffer so the panic handler can
- * draw the panic screen on it. Currently only linear buffer and a few color
- * formats are supported.
- * Optionally the driver can also provide a &drm_plane_helper_funcs.panic_flush
- * callback, that will be called after that, to send additional commands to the
- * hardware to make the scanout buffer visible.
- */
-
-/*
- * This module displays a user friendly message on screen when a kernel panic
- * occurs. This is conflicting with fbcon, so you can only enable it when fbcon
- * is disabled.
- * It's intended for end-user, so have minimal technical/debug information.
+ * This module displays a user friendly message on screen when a kernel
+ * panic occurs. This is conflicting with fbcon, so you can only enable
+ * it when fbcon is disabled. It's intended for end users and therefore
+ * have minimal technical/debug information.
*
- * Implementation details:
+ * To enable DRM panic for a driver, the at least one primary plane must
+ * implement struct &drm_plane_funcs.display_panic_screen. The plane is
+ * then automatically registered to the drm panic handler.
*
- * It is a panic handler, so it can't take lock, allocate memory, run
tasks/irq,
- * or attempt to sleep. It's a best effort, and it may not be able to display
- * the message in all situations (like if the panic occurs in the middle of a
- * modesetting).
- * It will display only one static frame, so performance optimizations are low
- * priority as the machine is already in an unusable state.
+ * When a panic occurs, the DRM panic handler calls struct
+ * &drm_plane_funcs.display_panic_screen. See
+ * drm_plane_helper_display_panic_screen() for a generic implementation.
*/
struct drm_panic_line {
@@ -821,12 +808,6 @@ static void drm_panic_qr_init(void) {};
static void drm_panic_qr_exit(void) {};
#endif
-enum drm_panic_type {
- DRM_PANIC_TYPE_KMSG,
- DRM_PANIC_TYPE_USER,
- DRM_PANIC_TYPE_QR,
-};
-
static enum drm_panic_type drm_panic_type = -1;
static const char *drm_panic_type_map[] = {
@@ -940,9 +921,29 @@ static void drm_panic_clear_description(void)
desc_line->txt = NULL;
}
-static void draw_panic_plane(struct drm_plane *plane, const char *description,
- enum drm_panic_type panic_type, u32 fg_color, u32
bg_color,
- unsigned int qr_version)
+/**
+ * drm_plane_helper_display_panic_screen - Displays a panic screen according
to the given settings
+ * @plane: the DRM plane to display to
+ * @description: error message to display
+ * @panic_type: type of panic screen
+ * @fg_color: text foreground color
+ * @bg_color: text background color
+ * @qr_version: version of the QR code, if any
+ *
+ * This helper display a panic screen on common primary planes. The panic
+ * screen can either display a kernel message, a user message or a QR code.
+ *
+ * The helper uses struct drm_plane_helper_funcs.get_scanout_buffer, where
+ * the plane can provide a scanout buffer that the panic handler can draw to.
+ * Currently only linear buffer and a few color formats are supported.
+ *
+ * Optionally the plane can also provide a &drm_plane_helper_funcs.panic_flush
+ * callback, which the DRM panic handler calls after drawing to send additional
+ * commands to the hardware to make the scanout buffer visible.
+ */
+void drm_plane_helper_display_panic_screen(struct drm_plane *plane, const char
*description,
+ enum drm_panic_type panic_type,
+ u32 fg_color, u32 bg_color, unsigned
int qr_version)
{
struct drm_scanout_buffer sb = { };
int ret;
@@ -970,6 +971,7 @@ static void draw_panic_plane(struct drm_plane *plane, const
char *description,
drm_panic_clear_description();
}
+EXPORT_SYMBOL(drm_plane_helper_display_panic_screen);
static void drm_panic_display_panic_screen(struct drm_plane *plane, const char *description)
{
@@ -992,8 +994,8 @@ static void drm_panic_display_panic_screen(struct drm_plane
*plane, const char *
unsigned long flags;
if (drm_panic_trylock(dev, flags)) {
- draw_panic_plane(plane, description, drm_panic_type,
- fg_color, bg_color, qr_version);
+ plane->funcs->display_panic_screen(plane, description,
drm_panic_type,
+ fg_color, bg_color,
qr_version);
drm_panic_unlock(dev, flags);
}
}
@@ -1064,7 +1066,7 @@ bool drm_panic_is_enabled(struct drm_device *dev)
return false;
drm_for_each_plane(plane, dev)
- if (plane->helper_private &&
plane->helper_private->get_scanout_buffer)
+ if (plane->funcs && plane->funcs->display_panic_screen)
return true;
return false;
}
@@ -1083,7 +1085,7 @@ void drm_panic_register(struct drm_device *dev)
return;
drm_for_each_plane(plane, dev) {
- if (!plane->helper_private ||
!plane->helper_private->get_scanout_buffer)
+ if (!plane->funcs || !plane->funcs->display_panic_screen)
continue;
plane->kmsg_panic.dump = drm_panic;
plane->kmsg_panic.max_reason = KMSG_DUMP_PANIC;
@@ -1110,7 +1112,7 @@ void drm_panic_unregister(struct drm_device *dev)
return;
drm_for_each_plane(plane, dev) {
- if (!plane->helper_private ||
!plane->helper_private->get_scanout_buffer)
+ if (!plane->funcs || !plane->funcs->display_panic_screen)
continue;
kmsg_dump_unregister(&plane->kmsg_panic);
}
diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
index 1855749c1e41..3bf228ef97ff 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
@@ -18,6 +18,7 @@
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_plane.h>
#include <drm/drm_print.h>
#include <drm/drm_vblank.h>
@@ -237,6 +238,7 @@ static const struct drm_plane_funcs hv_drm_plane_funcs = {
.disable_plane = drm_atomic_helper_disable_plane,
.destroy = drm_plane_cleanup,
DRM_GEM_SHADOW_PLANE_FUNCS,
+ DRM_PANIC_PLANE_FUNCS,
};
static const struct drm_encoder_funcs hv_drm_simple_encoder_funcs_cleanup = {
diff --git a/drivers/gpu/drm/i915/display/i9xx_plane.c
b/drivers/gpu/drm/i915/display/i9xx_plane.c
index df6da1c6a359..0902b17d0269 100644
--- a/drivers/gpu/drm/i915/display/i9xx_plane.c
+++ b/drivers/gpu/drm/i915/display/i9xx_plane.c
@@ -8,6 +8,7 @@
#include <drm/drm_atomic_helper.h>
#include <drm/drm_blend.h>
#include <drm/drm_fourcc.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include "i9xx_plane.h"
@@ -887,6 +888,7 @@ static const struct drm_plane_funcs i965_plane_funcs = {
.atomic_destroy_state = intel_plane_destroy_state,
.format_mod_supported = i965_plane_format_mod_supported,
.format_mod_supported_async = intel_plane_format_mod_supported_async,
+ DRM_PANIC_PLANE_FUNCS,
};
static const struct drm_plane_funcs i8xx_plane_funcs = {
@@ -897,6 +899,7 @@ static const struct drm_plane_funcs i8xx_plane_funcs = {
.atomic_destroy_state = intel_plane_destroy_state,
.format_mod_supported = i8xx_plane_format_mod_supported,
.format_mod_supported_async = intel_plane_format_mod_supported_async,
+ DRM_PANIC_PLANE_FUNCS,
};
static void i9xx_disable_tiling(struct intel_plane *plane)
diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c
b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index 07a683293352..45e8379d93d4 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -7,6 +7,7 @@
#include <drm/drm_blend.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_fourcc.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include <drm/intel/step.h>
@@ -2707,6 +2708,7 @@ static const struct drm_plane_funcs skl_plane_funcs = {
.atomic_destroy_state = intel_plane_destroy_state,
.format_mod_supported = skl_plane_format_mod_supported,
.format_mod_supported_async = intel_plane_format_mod_supported_async,
+ DRM_PANIC_PLANE_FUNCS,
};
static const struct drm_plane_funcs icl_plane_funcs = {
@@ -2717,6 +2719,7 @@ static const struct drm_plane_funcs icl_plane_funcs = {
.atomic_destroy_state = intel_plane_destroy_state,
.format_mod_supported = icl_plane_format_mod_supported,
.format_mod_supported_async = intel_plane_format_mod_supported_async,
+ DRM_PANIC_PLANE_FUNCS,
};
static const struct drm_plane_funcs tgl_plane_funcs = {
@@ -2727,6 +2730,7 @@ static const struct drm_plane_funcs tgl_plane_funcs = {
.atomic_destroy_state = intel_plane_destroy_state,
.format_mod_supported = tgl_plane_format_mod_supported,
.format_mod_supported_async = intel_plane_format_mod_supported_async,
+ DRM_PANIC_PLANE_FUNCS,
};
static void
diff --git a/drivers/gpu/drm/imx/ipuv3/ipuv3-plane.c
b/drivers/gpu/drm/imx/ipuv3/ipuv3-plane.c
index c7ec09e557c1..377db7cea726 100644
--- a/drivers/gpu/drm/imx/ipuv3/ipuv3-plane.c
+++ b/drivers/gpu/drm/imx/ipuv3/ipuv3-plane.c
@@ -14,6 +14,7 @@
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_managed.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include <video/imx-ipu-v3.h>
@@ -362,6 +363,7 @@ static const struct drm_plane_funcs ipu_plane_funcs = {
.atomic_duplicate_state = ipu_plane_duplicate_state,
.atomic_destroy_state = ipu_plane_destroy_state,
.format_mod_supported = ipu_plane_format_mod_supported,
+ DRM_PANIC_PLANE_FUNCS,
};
static int ipu_plane_atomic_check(struct drm_plane *plane,
diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h
b/drivers/gpu/drm/mgag200/mgag200_drv.h
index 3732c62351bb..d3995ce876f4 100644
--- a/drivers/gpu/drm/mgag200/mgag200_drv.h
+++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
@@ -17,6 +17,7 @@
#include <drm/drm_encoder.h>
#include <drm/drm_gem.h>
#include <drm/drm_gem_shmem_helper.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_plane.h>
#include "mgag200_reg.h"
@@ -386,7 +387,8 @@ int mgag200_primary_plane_helper_get_scanout_buffer(struct
drm_plane *plane,
.update_plane = drm_atomic_helper_update_plane, \
.disable_plane = drm_atomic_helper_disable_plane, \
.destroy = drm_plane_cleanup, \
- DRM_GEM_SHADOW_PLANE_FUNCS
+ DRM_GEM_SHADOW_PLANE_FUNCS, \
+ DRM_PANIC_PLANE_FUNCS
void mgag200_crtc_fill_gamma(struct mga_device *mdev, const struct drm_format_info *format);
void mgag200_crtc_load_gamma(struct mga_device *mdev,
diff --git a/drivers/gpu/drm/nouveau/dispnv50/wndw.c
b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
index 15a322422f4e..fc29a291e96f 100644
--- a/drivers/gpu/drm/nouveau/dispnv50/wndw.c
+++ b/drivers/gpu/drm/nouveau/dispnv50/wndw.c
@@ -39,6 +39,7 @@
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/ttm/ttm_bo.h>
#include "nouveau_bo.h"
@@ -841,6 +842,7 @@ nv50_wndw = {
.atomic_duplicate_state = nv50_wndw_atomic_duplicate_state,
.atomic_destroy_state = nv50_wndw_atomic_destroy_state,
.format_mod_supported = nv50_plane_format_mod_supported,
+ DRM_PANIC_PLANE_FUNCS,
};
static const u64 nv50_cursor_format_modifiers[] = {
diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_plane.c
b/drivers/gpu/drm/renesas/rcar-du/rcar_du_plane.c
index 8870766b9e54..f4b0e5b70c7d 100644
--- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_plane.c
+++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_plane.c
@@ -16,6 +16,7 @@
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_panic_helper.h>
#include "rcar_du_drv.h"
#include "rcar_du_group.h"
@@ -773,6 +774,7 @@ static const struct drm_plane_funcs rcar_du_plane_funcs = {
.atomic_destroy_state = rcar_du_plane_atomic_destroy_state,
.atomic_set_property = rcar_du_plane_atomic_set_property,
.atomic_get_property = rcar_du_plane_atomic_get_property,
+ DRM_PANIC_PLANE_FUNCS,
};
static const uint32_t formats[] = {
diff --git a/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
b/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
index 148de34af785..907f85462fa0 100644
--- a/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
+++ b/drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c
@@ -14,6 +14,7 @@
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_panic_helper.h>
#include "shmob_drm_drv.h"
#include "shmob_drm_kms.h"
@@ -286,6 +287,7 @@ static const struct drm_plane_funcs shmob_drm_plane_funcs =
{
.reset = shmob_drm_plane_reset,
.atomic_duplicate_state = shmob_drm_plane_atomic_duplicate_state,
.atomic_destroy_state = shmob_drm_plane_atomic_destroy_state,
+ DRM_PANIC_PLANE_FUNCS,
};
static const uint32_t formats[] = {
diff --git a/drivers/gpu/drm/sysfb/drm_sysfb_helper.h
b/drivers/gpu/drm/sysfb/drm_sysfb_helper.h
index 547f2327af5e..232be339659e 100644
--- a/drivers/gpu/drm/sysfb/drm_sysfb_helper.h
+++ b/drivers/gpu/drm/sysfb/drm_sysfb_helper.h
@@ -12,6 +12,7 @@
#include <drm/drm_device.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_modes.h>
+#include <drm/drm_panic_helper.h>
struct drm_format_info;
struct drm_scanout_buffer;
@@ -144,7 +145,8 @@ void drm_sysfb_plane_atomic_destroy_state(struct drm_plane
*plane,
.update_plane = drm_atomic_helper_update_plane, \
.disable_plane = drm_atomic_helper_disable_plane, \
.atomic_duplicate_state = drm_sysfb_plane_atomic_duplicate_state, \
- .atomic_destroy_state = drm_sysfb_plane_atomic_destroy_state
+ .atomic_destroy_state = drm_sysfb_plane_atomic_destroy_state, \
+ DRM_PANIC_PLANE_FUNCS
/*
* CRTC
diff --git a/drivers/gpu/drm/sysfb/vesadrm.c b/drivers/gpu/drm/sysfb/vesadrm.c
index 6a67b2d2e451..14d2e6ab88aa 100644
--- a/drivers/gpu/drm/sysfb/vesadrm.c
+++ b/drivers/gpu/drm/sysfb/vesadrm.c
@@ -24,6 +24,7 @@
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper.h>
#include <drm/drm_modeset_helper_vtables.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
diff --git a/drivers/gpu/drm/tidss/tidss_plane.c b/drivers/gpu/drm/tidss/tidss_plane.c
index 6d82976c2db1..b0d5d6959b88 100644
--- a/drivers/gpu/drm/tidss/tidss_plane.c
+++ b/drivers/gpu/drm/tidss/tidss_plane.c
@@ -12,6 +12,7 @@
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
+#include <drm/drm_panic_helper.h>
#include "tidss_crtc.h"
#include "tidss_dispc.h"
@@ -182,6 +183,7 @@ static const struct drm_plane_funcs tidss_plane_funcs = {
.atomic_create_state = drm_atomic_helper_plane_create_state,
.atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
+ DRM_PANIC_PLANE_FUNCS,
};
struct tidss_plane *tidss_plane_create(struct tidss_device *tidss,
diff --git a/drivers/gpu/drm/tiny/bochs.c b/drivers/gpu/drm/tiny/bochs.c
index e2d957e51505..076d19b26511 100644
--- a/drivers/gpu/drm/tiny/bochs.c
+++ b/drivers/gpu/drm/tiny/bochs.c
@@ -20,6 +20,7 @@
#include <drm/drm_managed.h>
#include <drm/drm_module.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
@@ -501,7 +502,8 @@ static const struct drm_plane_funcs
bochs_primary_plane_funcs = {
.update_plane = drm_atomic_helper_update_plane,
.disable_plane = drm_atomic_helper_disable_plane,
.destroy = drm_plane_cleanup,
- DRM_GEM_SHADOW_PLANE_FUNCS
+ DRM_GEM_SHADOW_PLANE_FUNCS,
+ DRM_PANIC_PLANE_FUNCS,
};
static void bochs_crtc_helper_mode_set_nofb(struct drm_crtc *crtc)
diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c
b/drivers/gpu/drm/virtio/virtgpu_plane.c
index 1d1b27ece62a..108b5b93f130 100644
--- a/drivers/gpu/drm/virtio/virtgpu_plane.c
+++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
@@ -30,6 +30,7 @@
#include <linux/virtio_dma_buf.h>
#include <drm/drm_managed.h>
#include <drm/drm_panic.h>
+#include <drm/drm_panic_helper.h>
#include <drm/drm_print.h>
#include "virtgpu_drv.h"
@@ -94,6 +95,7 @@ static const struct drm_plane_funcs virtio_gpu_plane_funcs = {
.reset = drm_atomic_helper_plane_reset,
.atomic_duplicate_state = virtio_gpu_plane_duplicate_state,
.atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
+ DRM_PANIC_PLANE_FUNCS,
};
static int virtio_gpu_plane_atomic_check(struct drm_plane *plane,
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index d8f5b7e9673e..084517beb924 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -495,8 +495,8 @@ struct drm_mode_config {
*
* Raw spinlock used to protect critical sections of code that access
* the display hardware or modeset software state, which the panic
- * printing code must be protected against. See drm_panic_trylock(),
- * drm_panic_lock() and drm_panic_unlock().
+ * printing code must be protected against. See the documentation on
+ * DRM panic handling for more information.
*/
struct raw_spinlock panic_lock;
diff --git a/include/drm/drm_modeset_helper_vtables.h b/include/drm/drm_modeset_helper_vtables.h
index ca6268945c28..614bdee0c1ed 100644
--- a/include/drm/drm_modeset_helper_vtables.h
+++ b/include/drm/drm_modeset_helper_vtables.h
@@ -1442,17 +1442,20 @@ struct drm_plane_helper_funcs {
/**
* @get_scanout_buffer:
*
- * Get the current scanout buffer, to display a message with drm_panic.
+ * Get the current scanout buffer to display a message with drm_panic.
* The driver should do the minimum changes to provide a buffer,
* that can be used to display the panic screen. Currently only linear
* buffers are supported. Non-linear buffer support is on the TODO list.
* The device &dev.mode_config.panic_lock is taken before calling this
* function, so you can safely access the &plane.state
* It is called from a panic callback, and must follow its restrictions.
- * Please look the documentation at drm_panic_trylock() for an in-depth
+ * Please look the documentation on DRM panic handling for an in-depth
* discussions of what's safe and what is not allowed.
+ *
* It's a best effort mode, so it's expected that in some complex cases
- * the panic screen won't be displayed.
+ * the panic screen won't be displayed. Drivers must not make any
+ * assumptions about the actual state of the hardware.
+ *
* The returned &drm_scanout_buffer.map must be valid if no error code
is
* returned.
*
@@ -1472,7 +1475,7 @@ struct drm_plane_helper_funcs {
* It is only called if get_scanout_buffer() returned successfully, and
* the &dev.mode_config.panic_lock is held during the entire sequence.
* It is called from a panic callback, and must follow its restrictions.
- * Please look the documentation at drm_panic_trylock() for an in-depth
+ * Please look the documentation on DRM panic handling for an in-depth
* discussions of what's safe and what is not allowed.
*/
void (*panic_flush)(struct drm_plane *plane);
diff --git a/include/drm/drm_panic.h b/include/drm/drm_panic.h
index ac0e46b73436..430df536de14 100644
--- a/include/drm/drm_panic.h
+++ b/include/drm/drm_panic.h
@@ -15,6 +15,14 @@
#include <drm/drm_device.h>
#include <drm/drm_fourcc.h>
+struct page;
+
+enum drm_panic_type {
+ DRM_PANIC_TYPE_KMSG,
+ DRM_PANIC_TYPE_USER,
+ DRM_PANIC_TYPE_QR,
+};
+
/**
* struct drm_scanout_buffer - DRM scanout buffer
*
@@ -87,45 +95,8 @@ struct drm_scanout_buffer {
* @dev: struct drm_device
* @flags: unsigned long irq flags you need to pass to the unlock()
counterpart
*
- * This function must be called by any panic printing code. The panic printing
- * attempt must be aborted if the trylock fails.
- *
- * Panic printing code can make the following assumptions while holding the
- * panic lock:
- *
- * - Anything protected by drm_panic_lock() and drm_panic_unlock() pairs is
safe
- * to access.
- *
- * - Furthermore the panic printing code only registers in drm_dev_unregister()
- * and gets removed in drm_dev_unregister(). This allows the panic code to
- * safely access any state which is invariant in between these two function
- * calls, like the list of planes &drm_mode_config.plane_list or most of the
- * struct drm_plane structure.
- *
- * Specifically thanks to the protection around plane updates in
- * drm_atomic_helper_swap_state() the following additional guarantees hold:
- *
- * - It is safe to deference the drm_plane.state pointer.
- *
- * - Anything in struct drm_plane_state or the driver's subclass thereof which
- * stays invariant after the atomic check code has finished is safe to
access.
- * Specifically this includes the reference counted pointers to framebuffer
- * and buffer objects.
- *
- * - Anything set up by &drm_plane_helper_funcs.fb_prepare and cleaned up
- * &drm_plane_helper_funcs.fb_cleanup is safe to access, as long as it stays
- * invariant between these two calls. This also means that for drivers using
- * dynamic buffer management the framebuffer is pinned, and therefer all
- * relevant datastructures can be accessed without taking any further locks
- * (which would be impossible in panic context anyway).
- *
- * - Importantly, software and hardware state set up by
- * &drm_plane_helper_funcs.begin_fb_access and
- * &drm_plane_helper_funcs.end_fb_access is not safe to access.
- *
- * Drivers must not make any assumptions about the actual state of the
hardware,
- * unless they explicitly protected these hardware access with drm_panic_lock()
- * and drm_panic_unlock().
+ * The panic-printing code calls this function. The panic printing attempt must
+ * be aborted if the trylock fails.
*
* Return:
* %0 when failing to acquire the raw spinlock, nonzero on success.
diff --git a/include/drm/drm_panic_helper.h b/include/drm/drm_panic_helper.h
new file mode 100644
index 000000000000..e296620bbe34
--- /dev/null
+++ b/include/drm/drm_panic_helper.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 or MIT */
+
+#ifndef __DRM_DRM_PANIC_HELPER_H_
+#define __DRM_DRM_PANIC_HELPER_H_
+
+#include <linux/types.h>
+
+enum drm_panic_type;
+
+struct drm_plane;
+
+/* drm_panic_helper.c */
+void drm_plane_helper_display_panic_screen(struct drm_plane *plane,
+ const char *description,
+ enum drm_panic_type panic_type,
+ u32 fg_color, u32 bg_color,
+ unsigned int qr_version);
+
+#if IS_ENABLED(CONFIG_DRM_PANIC)
+#define DRM_PANIC_PLANE_FUNCS \
+ .display_panic_screen = drm_plane_helper_display_panic_screen
+#else
+#define DRM_PANIC_PLANE_FUNCS \
+ .display_panic_screen = NULL
+#endif
+
+#endif
diff --git a/include/drm/drm_plane.h b/include/drm/drm_plane.h
index 2c5a5a70a71b..317af17bac26 100644
--- a/include/drm/drm_plane.h
+++ b/include/drm/drm_plane.h
@@ -32,6 +32,8 @@
#include <drm/drm_modeset_lock.h>
#include <drm/drm_util.h>
+enum drm_panic_type;
+
struct drm_crtc;
struct drm_plane_size_hint;
struct drm_printer;
@@ -590,6 +592,61 @@ struct drm_plane_funcs {
bool (*format_mod_supported_async)(struct drm_plane *plane,
u32 format, u64 modifier);
+ /**
+ * @display_panic_screen:
+ *
+ * DRM panic handling invokes this callback on panics.
+ *
+ * It is a panic handler, so it can't take locks, allocate memory, run
tasks/irq,
+ * or attempt to sleep. It's a best effort, and it may not be able to
display
+ * the message in all situations (like if the panic occurs in the
middle of a
+ * modesetting).
+ *
+ * Panic-printing code must acquire the panic lock before interacting
with the
+ * scanout buffer. Such helpers can make the following assumptions
while holding
+ * the panic lock:
+ *
+ * - Anything protected by drm_panic_lock() and drm_panic_unlock()
pairs is safe
+ * to access.
+ *
+ * - Furthermore the panic printing code only registers in
drm_dev_unregister()
+ * and gets removed in drm_dev_unregister(). This allows the panic
code to
+ * safely access any state which is invariant in between these two
function
+ * calls, like the list of planes &drm_mode_config.plane_list or most
of the
+ * struct drm_plane structure.
+ *
+ * Specifically thanks to the protection around plane updates in
+ * drm_atomic_helper_swap_state() the following additional guarantees
hold:
+ *
+ * - It is safe to deference the drm_plane.state pointer.
+ *
+ * - Anything in struct drm_plane_state or the driver's subclass
thereof which
+ * stays invariant after the atomic check code has finished is safe
to access.
+ * Specifically this includes the reference counted pointers to
framebuffer
+ * and buffer objects.
+ *
+ * - Anything set up by &drm_plane_helper_funcs.fb_prepare and cleaned
up
+ * &drm_plane_helper_funcs.fb_cleanup is safe to access, as long as
it stays
+ * invariant between these two calls. This also means that for
drivers using
+ * dynamic buffer management the framebuffer is pinned, and therefer
all
+ * relevant datastructures can be accessed without taking any further
locks
+ * (which would be impossible in panic context anyway).
+ *
+ * - Importantly, software and hardware state set up by
+ * &drm_plane_helper_funcs.begin_fb_access and
+ * &drm_plane_helper_funcs.end_fb_access is not safe to access.
+ *
+ * It will display only one static frame, so performance optimizations
are
+ * low priority as the machine is already in an unusable state.
+ *
+ * This callback is optional. Planes without will not be considered
+ * for panic output.
+ */
+ void (*display_panic_screen)(struct drm_plane *plane,
+ const char *description,
+ enum drm_panic_type panic_type,
+ u32 fg_color, u32 bg_color,
+ unsigned int qr_version);
};
/**
