2 * OMAP2+ common Power & Reset Management (PRM) IP block functions
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 * Tero Kristo <t-kristo@ti.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 * For historical purposes, the API used to configure the PRM
13 * interrupt handler refers to it as the "PRCM interrupt." The
14 * underlying registers are located in the PRM on OMAP3/4.
16 * XXX This code should eventually be moved to a PRM driver.
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
23 #include <linux/irq.h>
24 #include <linux/interrupt.h>
25 #include <linux/slab.h>
27 #include "../plat-omap/common.h"
29 #include "prm2xxx_3xxx.h"
36 * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
37 * XXX this is technically not needed, since
38 * omap_prcm_register_chain_handler() could allocate this based on the
39 * actual amount of memory needed for the SoC
41 #define OMAP_PRCM_MAX_NR_PENDING_REG 2
44 * prcm_irq_chips: an array of all of the "generic IRQ chips" in use
45 * by the PRCM interrupt handler code. There will be one 'chip' per
46 * PRM_{IRQSTATUS,IRQENABLE}_MPU register pair. (So OMAP3 will have
47 * one "chip" and OMAP4 will have two.)
49 static struct irq_chip_generic
**prcm_irq_chips
;
52 * prcm_irq_setup: the PRCM IRQ parameters for the hardware the code
53 * is currently running on. Defined and passed by initialization code
54 * that calls omap_prcm_register_chain_handler().
56 static struct omap_prcm_irq_setup
*prcm_irq_setup
;
58 /* prm_base: base virtual address of the PRM IP block */
59 void __iomem
*prm_base
;
62 * prm_ll_data: function pointers to SoC-specific implementations of
63 * common PRM functions
65 static struct prm_ll_data null_prm_ll_data
;
66 static struct prm_ll_data
*prm_ll_data
= &null_prm_ll_data
;
68 /* Private functions */
71 * Move priority events from events to priority_events array
73 static void omap_prcm_events_filter_priority(unsigned long *events
,
74 unsigned long *priority_events
)
78 for (i
= 0; i
< prcm_irq_setup
->nr_regs
; i
++) {
80 events
[i
] & prcm_irq_setup
->priority_mask
[i
];
81 events
[i
] ^= priority_events
[i
];
86 * PRCM Interrupt Handler
88 * This is a common handler for the OMAP PRCM interrupts. Pending
89 * interrupts are detected by a call to prcm_pending_events and
90 * dispatched accordingly. Clearing of the wakeup events should be
91 * done by the SoC specific individual handlers.
93 static void omap_prcm_irq_handler(unsigned int irq
, struct irq_desc
*desc
)
95 unsigned long pending
[OMAP_PRCM_MAX_NR_PENDING_REG
];
96 unsigned long priority_pending
[OMAP_PRCM_MAX_NR_PENDING_REG
];
97 struct irq_chip
*chip
= irq_desc_get_chip(desc
);
99 int nr_irq
= prcm_irq_setup
->nr_regs
* 32;
102 * If we are suspended, mask all interrupts from PRCM level,
103 * this does not ack them, and they will be pending until we
104 * re-enable the interrupts, at which point the
105 * omap_prcm_irq_handler will be executed again. The
106 * _save_and_clear_irqen() function must ensure that the PRM
107 * write to disable all IRQs has reached the PRM before
108 * returning, or spurious PRCM interrupts may occur during
111 if (prcm_irq_setup
->suspended
) {
112 prcm_irq_setup
->save_and_clear_irqen(prcm_irq_setup
->saved_mask
);
113 prcm_irq_setup
->suspend_save_flag
= true;
117 * Loop until all pending irqs are handled, since
118 * generic_handle_irq() can cause new irqs to come
120 while (!prcm_irq_setup
->suspended
) {
121 prcm_irq_setup
->read_pending_irqs(pending
);
123 /* No bit set, then all IRQs are handled */
124 if (find_first_bit(pending
, nr_irq
) >= nr_irq
)
127 omap_prcm_events_filter_priority(pending
, priority_pending
);
130 * Loop on all currently pending irqs so that new irqs
131 * cannot starve previously pending irqs
134 /* Serve priority events first */
135 for_each_set_bit(virtirq
, priority_pending
, nr_irq
)
136 generic_handle_irq(prcm_irq_setup
->base_irq
+ virtirq
);
138 /* Serve normal events next */
139 for_each_set_bit(virtirq
, pending
, nr_irq
)
140 generic_handle_irq(prcm_irq_setup
->base_irq
+ virtirq
);
143 chip
->irq_ack(&desc
->irq_data
);
145 chip
->irq_eoi(&desc
->irq_data
);
146 chip
->irq_unmask(&desc
->irq_data
);
148 prcm_irq_setup
->ocp_barrier(); /* avoid spurious IRQs */
151 /* Public functions */
154 * omap_prcm_event_to_irq - given a PRCM event name, returns the
155 * corresponding IRQ on which the handler should be registered
156 * @name: name of the PRCM interrupt bit to look up - see struct omap_prcm_irq
158 * Returns the Linux internal IRQ ID corresponding to @name upon success,
159 * or -ENOENT upon failure.
161 int omap_prcm_event_to_irq(const char *name
)
165 if (!prcm_irq_setup
|| !name
)
168 for (i
= 0; i
< prcm_irq_setup
->nr_irqs
; i
++)
169 if (!strcmp(prcm_irq_setup
->irqs
[i
].name
, name
))
170 return prcm_irq_setup
->base_irq
+
171 prcm_irq_setup
->irqs
[i
].offset
;
177 * omap_prcm_irq_cleanup - reverses memory allocated and other steps
178 * done by omap_prcm_register_chain_handler()
182 void omap_prcm_irq_cleanup(void)
186 if (!prcm_irq_setup
) {
187 pr_err("PRCM: IRQ handler not initialized; cannot cleanup\n");
191 if (prcm_irq_chips
) {
192 for (i
= 0; i
< prcm_irq_setup
->nr_regs
; i
++) {
193 if (prcm_irq_chips
[i
])
194 irq_remove_generic_chip(prcm_irq_chips
[i
],
196 prcm_irq_chips
[i
] = NULL
;
198 kfree(prcm_irq_chips
);
199 prcm_irq_chips
= NULL
;
202 kfree(prcm_irq_setup
->saved_mask
);
203 prcm_irq_setup
->saved_mask
= NULL
;
205 kfree(prcm_irq_setup
->priority_mask
);
206 prcm_irq_setup
->priority_mask
= NULL
;
208 irq_set_chained_handler(prcm_irq_setup
->irq
, NULL
);
210 if (prcm_irq_setup
->base_irq
> 0)
211 irq_free_descs(prcm_irq_setup
->base_irq
,
212 prcm_irq_setup
->nr_regs
* 32);
213 prcm_irq_setup
->base_irq
= 0;
216 void omap_prcm_irq_prepare(void)
218 prcm_irq_setup
->suspended
= true;
221 void omap_prcm_irq_complete(void)
223 prcm_irq_setup
->suspended
= false;
225 /* If we have not saved the masks, do not attempt to restore */
226 if (!prcm_irq_setup
->suspend_save_flag
)
229 prcm_irq_setup
->suspend_save_flag
= false;
232 * Re-enable all masked PRCM irq sources, this causes the PRCM
233 * interrupt to fire immediately if the events were masked
234 * previously in the chain handler
236 prcm_irq_setup
->restore_irqen(prcm_irq_setup
->saved_mask
);
240 * omap_prcm_register_chain_handler - initializes the prcm chained interrupt
241 * handler based on provided parameters
242 * @irq_setup: hardware data about the underlying PRM/PRCM
244 * Set up the PRCM chained interrupt handler on the PRCM IRQ. Sets up
245 * one generic IRQ chip per PRM interrupt status/enable register pair.
246 * Returns 0 upon success, -EINVAL if called twice or if invalid
247 * arguments are passed, or -ENOMEM on any other error.
249 int omap_prcm_register_chain_handler(struct omap_prcm_irq_setup
*irq_setup
)
252 u32 mask
[OMAP_PRCM_MAX_NR_PENDING_REG
];
254 struct irq_chip_generic
*gc
;
255 struct irq_chip_type
*ct
;
260 nr_regs
= irq_setup
->nr_regs
;
262 if (prcm_irq_setup
) {
263 pr_err("PRCM: already initialized; won't reinitialize\n");
267 if (nr_regs
> OMAP_PRCM_MAX_NR_PENDING_REG
) {
268 pr_err("PRCM: nr_regs too large\n");
272 prcm_irq_setup
= irq_setup
;
274 prcm_irq_chips
= kzalloc(sizeof(void *) * nr_regs
, GFP_KERNEL
);
275 prcm_irq_setup
->saved_mask
= kzalloc(sizeof(u32
) * nr_regs
, GFP_KERNEL
);
276 prcm_irq_setup
->priority_mask
= kzalloc(sizeof(u32
) * nr_regs
,
279 if (!prcm_irq_chips
|| !prcm_irq_setup
->saved_mask
||
280 !prcm_irq_setup
->priority_mask
) {
281 pr_err("PRCM: kzalloc failed\n");
285 memset(mask
, 0, sizeof(mask
));
287 for (i
= 0; i
< irq_setup
->nr_irqs
; i
++) {
288 offset
= irq_setup
->irqs
[i
].offset
;
289 mask
[offset
>> 5] |= 1 << (offset
& 0x1f);
290 if (irq_setup
->irqs
[i
].priority
)
291 irq_setup
->priority_mask
[offset
>> 5] |=
292 1 << (offset
& 0x1f);
295 irq_set_chained_handler(irq_setup
->irq
, omap_prcm_irq_handler
);
297 irq_setup
->base_irq
= irq_alloc_descs(-1, 0, irq_setup
->nr_regs
* 32,
300 if (irq_setup
->base_irq
< 0) {
301 pr_err("PRCM: failed to allocate irq descs: %d\n",
302 irq_setup
->base_irq
);
306 for (i
= 0; i
< irq_setup
->nr_regs
; i
++) {
307 gc
= irq_alloc_generic_chip("PRCM", 1,
308 irq_setup
->base_irq
+ i
* 32, prm_base
,
312 pr_err("PRCM: failed to allocate generic chip\n");
316 ct
->chip
.irq_ack
= irq_gc_ack_set_bit
;
317 ct
->chip
.irq_mask
= irq_gc_mask_clr_bit
;
318 ct
->chip
.irq_unmask
= irq_gc_mask_set_bit
;
320 ct
->regs
.ack
= irq_setup
->ack
+ i
* 4;
321 ct
->regs
.mask
= irq_setup
->mask
+ i
* 4;
323 irq_setup_generic_chip(gc
, mask
[i
], 0, IRQ_NOREQUEST
, 0);
324 prcm_irq_chips
[i
] = gc
;
330 omap_prcm_irq_cleanup();
335 * omap2_set_globals_prm - set the PRM base address (for early use)
336 * @prm: PRM base virtual address
338 * XXX Will be replaced when the PRM/CM drivers are completed.
340 void __init
omap2_set_globals_prm(void __iomem
*prm
)
346 * prm_read_reset_sources - return the sources of the SoC's last reset
348 * Return a u32 bitmask representing the reset sources that caused the
349 * SoC to reset. The low-level per-SoC functions called by this
350 * function remap the SoC-specific reset source bits into an
351 * OMAP-common set of reset source bits, defined in
352 * arch/arm/mach-omap2/prm.h. Returns the standardized reset source
353 * u32 bitmask from the hardware upon success, or returns (1 <<
354 * OMAP_UNKNOWN_RST_SRC_ID_SHIFT) if no low-level read_reset_sources()
355 * function was registered.
357 u32
prm_read_reset_sources(void)
359 u32 ret
= 1 << OMAP_UNKNOWN_RST_SRC_ID_SHIFT
;
361 if (prm_ll_data
->read_reset_sources
)
362 ret
= prm_ll_data
->read_reset_sources();
364 WARN_ONCE(1, "prm: %s: no mapping function defined for reset sources\n", __func__
);
370 * prm_register - register per-SoC low-level data with the PRM
371 * @pld: low-level per-SoC OMAP PRM data & function pointers to register
373 * Register per-SoC low-level OMAP PRM data and function pointers with
374 * the OMAP PRM common interface. The caller must keep the data
375 * pointed to by @pld valid until it calls prm_unregister() and
376 * it returns successfully. Returns 0 upon success, -EINVAL if @pld
377 * is NULL, or -EEXIST if prm_register() has already been called
378 * without an intervening prm_unregister().
380 int prm_register(struct prm_ll_data
*pld
)
385 if (prm_ll_data
!= &null_prm_ll_data
)
394 * prm_unregister - unregister per-SoC low-level data & function pointers
395 * @pld: low-level per-SoC OMAP PRM data & function pointers to unregister
397 * Unregister per-SoC low-level OMAP PRM data and function pointers
398 * that were previously registered with prm_register(). The
399 * caller may not destroy any of the data pointed to by @pld until
400 * this function returns successfully. Returns 0 upon success, or
401 * -EINVAL if @pld is NULL or if @pld does not match the struct
402 * prm_ll_data * previously registered by prm_register().
404 int prm_unregister(struct prm_ll_data
*pld
)
406 if (!pld
|| prm_ll_data
!= pld
)
409 prm_ll_data
= &null_prm_ll_data
;