diff options
Diffstat (limited to 'drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c')
| -rw-r--r-- | drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c | 115 |
1 files changed, 102 insertions, 13 deletions
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c index a212178f2edc..cd10f77cdeb0 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c @@ -32,16 +32,55 @@ #include "amdgpu_dm.h" #include "amdgpu_dm_irq.h" +/** + * DOC: overview + * + * DM provides another layer of IRQ management on top of what the base driver + * already provides. This is something that could be cleaned up, and is a + * future TODO item. + * + * The base driver provides IRQ source registration with DRM, handler + * registration into the base driver's IRQ table, and a handler callback + * amdgpu_irq_handler(), with which DRM calls on interrupts. This generic + * handler looks up the IRQ table, and calls the respective + * &amdgpu_irq_src_funcs.process hookups. + * + * What DM provides on top are two IRQ tables specifically for top-half and + * bottom-half IRQ handling, with the bottom-half implementing workqueues: + * + * - &amdgpu_display_manager.irq_handler_list_high_tab + * - &amdgpu_display_manager.irq_handler_list_low_tab + * + * They override the base driver's IRQ table, and the effect can be seen + * in the hooks that DM provides for &amdgpu_irq_src_funcs.process. They + * are all set to the DM generic handler amdgpu_dm_irq_handler(), which looks up + * DM's IRQ tables. However, in order for base driver to recognize this hook, DM + * still needs to register the IRQ with the base driver. See + * dce110_register_irq_handlers() and dcn10_register_irq_handlers(). + * + * To expose DC's hardware interrupt toggle to the base driver, DM implements + * &amdgpu_irq_src_funcs.set hooks. Base driver calls it through + * amdgpu_irq_update() to enable or disable the interrupt. + */ + /****************************************************************************** * Private declarations. *****************************************************************************/ +/** + * struct amdgpu_dm_irq_handler_data - Data for DM interrupt handlers. + * + * @list: Linked list entry referencing the next/previous handler + * @handler: Handler function + * @handler_arg: Argument passed to the handler when triggered + * @dm: DM which this handler belongs to + * @irq_source: DC interrupt source that this handler is registered for + */ struct amdgpu_dm_irq_handler_data { struct list_head list; interrupt_handler handler; void *handler_arg; - /* DM which this handler belongs to */ struct amdgpu_display_manager *dm; /* DAL irq source which registered for this interrupt. */ enum dc_irq_source irq_source; @@ -68,7 +107,7 @@ static void init_handler_common_data(struct amdgpu_dm_irq_handler_data *hcd, } /** - * dm_irq_work_func - Handle an IRQ outside of the interrupt handler proper. + * dm_irq_work_func() - Handle an IRQ outside of the interrupt handler proper. * * @work: work struct */ @@ -99,8 +138,8 @@ static void dm_irq_work_func(struct work_struct *work) * (The most common use is HPD interrupt) */ } -/** - * Remove a handler and return a pointer to hander list from which the +/* + * Remove a handler and return a pointer to handler list from which the * handler was removed. */ static struct list_head *remove_irq_handler(struct amdgpu_device *adev, @@ -203,6 +242,24 @@ static bool validate_irq_unregistration_params(enum dc_irq_source irq_source, * Note: caller is responsible for input validation. *****************************************************************************/ +/** + * amdgpu_dm_irq_register_interrupt() - Register a handler within DM. + * @adev: The base driver device containing the DM device. + * @int_params: Interrupt parameters containing the source, and handler context + * @ih: Function pointer to the interrupt handler to register + * @handler_args: Arguments passed to the handler when the interrupt occurs + * + * Register an interrupt handler for the given IRQ source, under the given + * context. The context can either be high or low. High context handlers are + * executed directly within ISR context, while low context is executed within a + * workqueue, thereby allowing operations that sleep. + * + * Registered handlers are called in a FIFO manner, i.e. the most recently + * registered handler will be called first. + * + * Return: Handler data &struct amdgpu_dm_irq_handler_data containing the IRQ + * source, handler function, and args + */ void *amdgpu_dm_irq_register_interrupt(struct amdgpu_device *adev, struct dc_interrupt_params *int_params, void (*ih)(void *), @@ -261,6 +318,15 @@ void *amdgpu_dm_irq_register_interrupt(struct amdgpu_device *adev, return handler_data; } +/** + * amdgpu_dm_irq_unregister_interrupt() - Remove a handler from the DM IRQ table + * @adev: The base driver device containing the DM device + * @irq_source: IRQ source to remove the given handler from + * @ih: Function pointer to the interrupt handler to unregister + * + * Go through both low and high context IRQ tables, and find the given handler + * for the given irq source. If found, remove it. Otherwise, do nothing. + */ void amdgpu_dm_irq_unregister_interrupt(struct amdgpu_device *adev, enum dc_irq_source irq_source, void *ih) @@ -295,6 +361,20 @@ void amdgpu_dm_irq_unregister_interrupt(struct amdgpu_device *adev, } } +/** + * amdgpu_dm_irq_init() - Initialize DM IRQ management + * @adev: The base driver device containing the DM device + * + * Initialize DM's high and low context IRQ tables. + * + * The N by M table contains N IRQ sources, with M + * &struct amdgpu_dm_irq_handler_data hooked together in a linked list. The + * list_heads are initialized here. When an interrupt n is triggered, all m + * handlers are called in sequence, FIFO according to registration order. + * + * The low context table requires special steps to initialize, since handlers + * will be deferred to a workqueue. See &struct irq_list_head. + */ int amdgpu_dm_irq_init(struct amdgpu_device *adev) { int src; @@ -317,7 +397,12 @@ int amdgpu_dm_irq_init(struct amdgpu_device *adev) return 0; } -/* DM IRQ and timer resource release */ +/** + * amdgpu_dm_irq_fini() - Tear down DM IRQ management + * @adev: The base driver device containing the DM device + * + * Flush all work within the low context IRQ table. + */ void amdgpu_dm_irq_fini(struct amdgpu_device *adev) { int src; @@ -414,7 +499,7 @@ int amdgpu_dm_irq_resume_late(struct amdgpu_device *adev) return 0; } -/** +/* * amdgpu_dm_irq_schedule_work - schedule all work items registered for the * "irq_source". */ @@ -439,8 +524,9 @@ static void amdgpu_dm_irq_schedule_work(struct amdgpu_device *adev, } -/** amdgpu_dm_irq_immediate_work - * Callback high irq work immediately, don't send to work queue +/* + * amdgpu_dm_irq_immediate_work + * Callback high irq work immediately, don't send to work queue */ static void amdgpu_dm_irq_immediate_work(struct amdgpu_device *adev, enum dc_irq_source irq_source) @@ -467,11 +553,14 @@ static void amdgpu_dm_irq_immediate_work(struct amdgpu_device *adev, DM_IRQ_TABLE_UNLOCK(adev, irq_table_flags); } -/* - * amdgpu_dm_irq_handler +/** + * amdgpu_dm_irq_handler - Generic DM IRQ handler + * @adev: amdgpu base driver device containing the DM device + * @source: Unused + * @entry: Data about the triggered interrupt * - * Generic IRQ handler, calls all registered high irq work immediately, and - * schedules work for low irq + * Calls all registered high irq work immediately, and schedules work for low + * irq. The DM IRQ table is used to find the corresponding handlers. */ static int amdgpu_dm_irq_handler(struct amdgpu_device *adev, struct amdgpu_irq_src *source, @@ -613,7 +702,7 @@ void amdgpu_dm_set_irq_funcs(struct amdgpu_device *adev) adev->hpd_irq.funcs = &dm_hpd_irq_funcs; } -/* +/** * amdgpu_dm_hpd_init - hpd setup callback. * * @adev: amdgpu_device pointer |