None of the DRM drivers handles panic locking. Declare the interfaces in an internal header file. Move the trylock required during the panic into the DRM core's sources.
Signed-off-by: Thomas Zimmermann <[email protected]> --- Documentation/gpu/drm-kms.rst | 3 ++ MAINTAINERS | 3 +- drivers/gpu/drm/drm_atomic_helper.c | 2 +- drivers/gpu/drm/drm_drv.c | 2 +- drivers/gpu/drm/drm_panic.c | 4 ++ drivers/gpu/drm/drm_panic_internal.h | 55 +++++++++++++++++++++++ include/drm/drm_panic.h | 65 ---------------------------- 7 files changed, 66 insertions(+), 68 deletions(-) create mode 100644 drivers/gpu/drm/drm_panic_internal.h diff --git a/Documentation/gpu/drm-kms.rst b/Documentation/gpu/drm-kms.rst index 0dd440a14946..8988fd64369b 100644 --- a/Documentation/gpu/drm-kms.rst +++ b/Documentation/gpu/drm-kms.rst @@ -421,6 +421,9 @@ Plane Panic Functions Reference .. kernel-doc:: include/drm/drm_panic.h :internal: +.. kernel-doc:: drivers/gpu/drm/drm_panic_internal.h + :internal: + .. kernel-doc:: drivers/gpu/drm/drm_panic.c :export: diff --git a/MAINTAINERS b/MAINTAINERS index 472c5c48729d..f3dfdd9314bd 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9018,7 +9018,8 @@ S: Supported T: git https://gitlab.freedesktop.org/drm/misc/kernel.git 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/drm_panic.c +F: drivers/gpu/drm/drm_panic_internal.h F: drivers/gpu/drm/tests/drm_panic_test.c F: include/drm/drm_panic.h F: include/drm/drm_panic_helper.h diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 285aac3554df..af3934df3313 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -41,7 +41,6 @@ #include <drm/drm_drv.h> #include <drm/drm_framebuffer.h> #include <drm/drm_gem_atomic_helper.h> -#include <drm/drm_panic.h> #include <drm/drm_print.h> #include <drm/drm_self_refresh_helper.h> #include <drm/drm_vblank.h> @@ -49,6 +48,7 @@ #include "drm_crtc_helper_internal.h" #include "drm_crtc_internal.h" +#include "drm_panic_internal.h" /** * DOC: overview diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index c808958a2188..02ff02931515 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -50,13 +50,13 @@ #include <drm/drm_file.h> #include <drm/drm_managed.h> #include <drm/drm_mode_object.h> -#include <drm/drm_panic.h> #include <drm/drm_print.h> #include <drm/drm_privacy_screen_machine.h> #include <drm/drm_ras_genl_family.h> #include "drm_crtc_internal.h" #include "drm_internal.h" +#include "drm_panic_internal.h" MODULE_AUTHOR("Gareth Hughes, Leif Delgass, José Fonseca, Jon Smirl"); MODULE_DESCRIPTION("DRM shared core routines"); diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c index 2ecb4d1f6d47..b3a71fddf2de 100644 --- a/drivers/gpu/drm/drm_panic.c +++ b/drivers/gpu/drm/drm_panic.c @@ -35,6 +35,7 @@ #include "drm_crtc_internal.h" #include "drm_draw_internal.h" +#include "drm_panic_internal.h" MODULE_AUTHOR("Jocelyn Falempe"); MODULE_DESCRIPTION("DRM panic handler"); @@ -973,6 +974,9 @@ void drm_plane_helper_display_panic_screen(struct drm_plane *plane, const char * } EXPORT_SYMBOL(drm_plane_helper_display_panic_screen); +#define drm_panic_trylock(dev, flags) \ + raw_spin_trylock_irqsave(&(dev)->mode_config.panic_lock, flags) + static void drm_panic_display_panic_screen(struct drm_plane *plane, const char *description) { #if defined(CONFIG_DRM_PANIC_FOREGROUND_COLOR) diff --git a/drivers/gpu/drm/drm_panic_internal.h b/drivers/gpu/drm/drm_panic_internal.h new file mode 100644 index 000000000000..c68d64c56e15 --- /dev/null +++ b/drivers/gpu/drm/drm_panic_internal.h @@ -0,0 +1,55 @@ +/* SPDX-License-Identifier: GPL-2.0 or MIT */ + +/* + * Copyright (c) 2024 Intel + * Copyright (c) 2024 Red Hat + */ + +#ifndef __DRM_PANIC_INTERNAL_H__ +#define __DRM_PANIC_INTERNAL_H__ + +#include <linux/spinlock.h> + +struct drm_device; + +#ifdef CONFIG_DRM_PANIC + +/** + * drm_panic_lock - protect panic printing relevant state + * @dev: struct drm_device + * @flags: unsigned long irq flags you need to pass to the unlock() counterpart + * + * This function must be called to protect software and hardware state that the + * panic printing code must be able to rely on. The protected sections must be + * as small as possible. It uses the irqsave/irqrestore variant, and can be + * called from irq handler. Examples include: + * + * - Access to peek/poke or other similar registers, if that is the way the + * driver prints the pixels into the scanout buffer at panic time. + * + * - Updates to pointers like &drm_plane.state, allowing the panic handler to + * safely deference these. This is done in drm_atomic_helper_swap_state(). + * + * - An state that isn't invariant and that the driver must be able to access + * during panic printing. + */ +#define drm_panic_lock(dev, flags) \ + raw_spin_lock_irqsave(&(dev)->mode_config.panic_lock, flags) + +/** + * drm_panic_unlock - end of the panic printing critical section + * @dev: struct drm_device + * @flags: irq flags that were returned when acquiring the lock + * + * Unlocks the raw spinlock acquired by either drm_panic_lock() or + * drm_panic_trylock(). + */ +#define drm_panic_unlock(dev, flags) \ + raw_spin_unlock_irqrestore(&(dev)->mode_config.panic_lock, flags) + +#else +static inline void drm_panic_lock(struct drm_device *dev, unsigned long flags) {} +static inline void drm_panic_unlock(struct drm_device *dev, unsigned long flags) {} +#endif + +#endif /* __DRM_PANIC_INTERNAL_H__ */ diff --git a/include/drm/drm_panic.h b/include/drm/drm_panic.h index 430df536de14..99572b7eeab9 100644 --- a/include/drm/drm_panic.h +++ b/include/drm/drm_panic.h @@ -8,11 +8,9 @@ #ifndef __DRM_PANIC_H__ #define __DRM_PANIC_H__ -#include <linux/module.h> #include <linux/types.h> #include <linux/iosys-map.h> -#include <drm/drm_device.h> #include <drm/drm_fourcc.h> struct page; @@ -85,71 +83,8 @@ struct drm_scanout_buffer { * set_pixel() */ void *private; - }; -#ifdef CONFIG_DRM_PANIC - -/** - * drm_panic_trylock - try to enter the panic printing critical section - * @dev: struct drm_device - * @flags: unsigned long irq flags you need to pass to the unlock() counterpart - * - * 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. - */ -#define drm_panic_trylock(dev, flags) \ - raw_spin_trylock_irqsave(&(dev)->mode_config.panic_lock, flags) - -/** - * drm_panic_lock - protect panic printing relevant state - * @dev: struct drm_device - * @flags: unsigned long irq flags you need to pass to the unlock() counterpart - * - * This function must be called to protect software and hardware state that the - * panic printing code must be able to rely on. The protected sections must be - * as small as possible. It uses the irqsave/irqrestore variant, and can be - * called from irq handler. Examples include: - * - * - Access to peek/poke or other similar registers, if that is the way the - * driver prints the pixels into the scanout buffer at panic time. - * - * - Updates to pointers like &drm_plane.state, allowing the panic handler to - * safely deference these. This is done in drm_atomic_helper_swap_state(). - * - * - An state that isn't invariant and that the driver must be able to access - * during panic printing. - */ - -#define drm_panic_lock(dev, flags) \ - raw_spin_lock_irqsave(&(dev)->mode_config.panic_lock, flags) - -/** - * drm_panic_unlock - end of the panic printing critical section - * @dev: struct drm_device - * @flags: irq flags that were returned when acquiring the lock - * - * Unlocks the raw spinlock acquired by either drm_panic_lock() or - * drm_panic_trylock(). - */ -#define drm_panic_unlock(dev, flags) \ - raw_spin_unlock_irqrestore(&(dev)->mode_config.panic_lock, flags) - -#else - -static inline bool drm_panic_trylock(struct drm_device *dev, unsigned long flags) -{ - return true; -} - -static inline void drm_panic_lock(struct drm_device *dev, unsigned long flags) {} -static inline void drm_panic_unlock(struct drm_device *dev, unsigned long flags) {} - -#endif - #if defined(CONFIG_DRM_PANIC_SCREEN_QR_CODE) size_t drm_panic_qr_max_data_size(u8 version, size_t url_len); -- 2.55.0
