4 Copyright 2008, 2009 Michel Pollet <buserror@gmail.com>
6 This file is part of simavr.
8 simavr is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
13 simavr is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with simavr. If not, see <http://www.gnu.org/licenses/>.
30 * This subsystem allow any piece of code to "register" a hook to be called when an IRQ is
31 * raised. The IRQ definition is up to the module defining it, for example a IOPORT pin change
32 * might be an IRQ in wich case any oiece of code can be notified when a pin has changed state
34 * The notify hooks are chained, and duplicates are filtered out so you can't register a
35 * notify hook twice on one particylar IRQ
37 * IRQ calling order is not defined, so don't rely on it.
39 * IRQ hook needs to be registered in reset() handlers, ie after all modules init() bits
40 * have been called, to prevent race condition of the initialization order.
44 typedef void (*avr_irq_notify_t)(struct avr_irq_t * irq, uint32_t value, void * param);
46 // internal structure for a hook, never seen by the notify procs
47 typedef struct avr_irq_hook_t {
48 struct avr_irq_hook_t * next;
49 int busy; // prevent reentrance of callbacks
51 struct avr_irq_t * chain; // raise the IRQ on this too - optional if "notify" is on
52 avr_irq_notify_t notify; // called when IRQ is raised - optional if "chain" is on
53 void * param; // "notify" parameter
57 IRQ_FLAG_NOT = (1 << 0), // change polarity of the IRQ
58 IRQ_FLAG_FILTERED = (1 << 1), // do not "notify" if "value" is the same as previous raise
59 IRQ_FLAG_ALLOC = (1 << 2), // this irq structure was malloced via avr_alloc_irq
63 * Public IRQ structure
65 typedef struct avr_irq_t {
68 uint8_t flags; // IRQ_*
69 avr_irq_hook_t * hook;
72 avr_irq_t * avr_alloc_irq(uint32_t base, uint32_t count);
73 void avr_free_irq(avr_irq_t * irq, uint32_t count);
75 void avr_init_irq(avr_irq_t * irq, uint32_t base, uint32_t count);
76 void avr_raise_irq(avr_irq_t * irq, uint32_t value);
77 // this connects a "source" IRQ to a "destination" IRQ
78 void avr_connect_irq(avr_irq_t * src, avr_irq_t * dst);
79 void avr_irq_register_notify(avr_irq_t * irq, avr_irq_notify_t notify, void * param);
81 #endif /* __SIM_IRQ_H__ */