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"
28 #include <plat/prcm.h>
30 #include "prm2xxx_3xxx.h"
37 * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs
38 * XXX this is technically not needed, since
39 * omap_prcm_register_chain_handler() could allocate this based on the
40 * actual amount of memory needed for the SoC
42 #define OMAP_PRCM_MAX_NR_PENDING_REG 2
45 * prcm_irq_chips: an array of all of the "generic IRQ chips" in use
46 * by the PRCM interrupt handler code. There will be one 'chip' per
47 * PRM_{IRQSTATUS,IRQENABLE}_MPU register pair. (So OMAP3 will have
48 * one "chip" and OMAP4 will have two.)
50 static struct irq_chip_generic **prcm_irq_chips;
53 * prcm_irq_setup: the PRCM IRQ parameters for the hardware the code
54 * is currently running on. Defined and passed by initialization code
55 * that calls omap_prcm_register_chain_handler().
57 static struct omap_prcm_irq_setup *prcm_irq_setup;
59 /* prm_base: base virtual address of the PRM IP block */
60 void __iomem *prm_base;
63 * prm_ll_data: function pointers to SoC-specific implementations of
64 * common PRM functions
66 static struct prm_ll_data null_prm_ll_data;
67 static struct prm_ll_data *prm_ll_data = &null_prm_ll_data;
69 /* Private functions */
72 * Move priority events from events to priority_events array
74 static void omap_prcm_events_filter_priority(unsigned long *events,
75 unsigned long *priority_events)
79 for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
81 events[i] & prcm_irq_setup->priority_mask[i];
82 events[i] ^= priority_events[i];
87 * PRCM Interrupt Handler
89 * This is a common handler for the OMAP PRCM interrupts. Pending
90 * interrupts are detected by a call to prcm_pending_events and
91 * dispatched accordingly. Clearing of the wakeup events should be
92 * done by the SoC specific individual handlers.
94 static void omap_prcm_irq_handler(unsigned int irq, struct irq_desc *desc)
96 unsigned long pending[OMAP_PRCM_MAX_NR_PENDING_REG];
97 unsigned long priority_pending[OMAP_PRCM_MAX_NR_PENDING_REG];
98 struct irq_chip *chip = irq_desc_get_chip(desc);
100 int nr_irq = prcm_irq_setup->nr_regs * 32;
103 * If we are suspended, mask all interrupts from PRCM level,
104 * this does not ack them, and they will be pending until we
105 * re-enable the interrupts, at which point the
106 * omap_prcm_irq_handler will be executed again. The
107 * _save_and_clear_irqen() function must ensure that the PRM
108 * write to disable all IRQs has reached the PRM before
109 * returning, or spurious PRCM interrupts may occur during
112 if (prcm_irq_setup->suspended) {
113 prcm_irq_setup->save_and_clear_irqen(prcm_irq_setup->saved_mask);
114 prcm_irq_setup->suspend_save_flag = true;
118 * Loop until all pending irqs are handled, since
119 * generic_handle_irq() can cause new irqs to come
121 while (!prcm_irq_setup->suspended) {
122 prcm_irq_setup->read_pending_irqs(pending);
124 /* No bit set, then all IRQs are handled */
125 if (find_first_bit(pending, nr_irq) >= nr_irq)
128 omap_prcm_events_filter_priority(pending, priority_pending);
131 * Loop on all currently pending irqs so that new irqs
132 * cannot starve previously pending irqs
135 /* Serve priority events first */
136 for_each_set_bit(virtirq, priority_pending, nr_irq)
137 generic_handle_irq(prcm_irq_setup->base_irq + virtirq);
139 /* Serve normal events next */
140 for_each_set_bit(virtirq, pending, nr_irq)
141 generic_handle_irq(prcm_irq_setup->base_irq + virtirq);
144 chip->irq_ack(&desc->irq_data);
146 chip->irq_eoi(&desc->irq_data);
147 chip->irq_unmask(&desc->irq_data);
149 prcm_irq_setup->ocp_barrier(); /* avoid spurious IRQs */
152 /* Public functions */
155 * omap_prcm_event_to_irq - given a PRCM event name, returns the
156 * corresponding IRQ on which the handler should be registered
157 * @name: name of the PRCM interrupt bit to look up - see struct omap_prcm_irq
159 * Returns the Linux internal IRQ ID corresponding to @name upon success,
160 * or -ENOENT upon failure.
162 int omap_prcm_event_to_irq(const char *name)
166 if (!prcm_irq_setup || !name)
169 for (i = 0; i < prcm_irq_setup->nr_irqs; i++)
170 if (!strcmp(prcm_irq_setup->irqs[i].name, name))
171 return prcm_irq_setup->base_irq +
172 prcm_irq_setup->irqs[i].offset;
178 * omap_prcm_irq_cleanup - reverses memory allocated and other steps
179 * done by omap_prcm_register_chain_handler()
183 void omap_prcm_irq_cleanup(void)
187 if (!prcm_irq_setup) {
188 pr_err("PRCM: IRQ handler not initialized; cannot cleanup\n");
192 if (prcm_irq_chips) {
193 for (i = 0; i < prcm_irq_setup->nr_regs; i++) {
194 if (prcm_irq_chips[i])
195 irq_remove_generic_chip(prcm_irq_chips[i],
197 prcm_irq_chips[i] = NULL;
199 kfree(prcm_irq_chips);
200 prcm_irq_chips = NULL;
203 kfree(prcm_irq_setup->saved_mask);
204 prcm_irq_setup->saved_mask = NULL;
206 kfree(prcm_irq_setup->priority_mask);
207 prcm_irq_setup->priority_mask = NULL;
209 irq_set_chained_handler(prcm_irq_setup->irq, NULL);
211 if (prcm_irq_setup->base_irq > 0)
212 irq_free_descs(prcm_irq_setup->base_irq,
213 prcm_irq_setup->nr_regs * 32);
214 prcm_irq_setup->base_irq = 0;
217 void omap_prcm_irq_prepare(void)
219 prcm_irq_setup->suspended = true;
222 void omap_prcm_irq_complete(void)
224 prcm_irq_setup->suspended = false;
226 /* If we have not saved the masks, do not attempt to restore */
227 if (!prcm_irq_setup->suspend_save_flag)
230 prcm_irq_setup->suspend_save_flag = false;
233 * Re-enable all masked PRCM irq sources, this causes the PRCM
234 * interrupt to fire immediately if the events were masked
235 * previously in the chain handler
237 prcm_irq_setup->restore_irqen(prcm_irq_setup->saved_mask);
241 * omap_prcm_register_chain_handler - initializes the prcm chained interrupt
242 * handler based on provided parameters
243 * @irq_setup: hardware data about the underlying PRM/PRCM
245 * Set up the PRCM chained interrupt handler on the PRCM IRQ. Sets up
246 * one generic IRQ chip per PRM interrupt status/enable register pair.
247 * Returns 0 upon success, -EINVAL if called twice or if invalid
248 * arguments are passed, or -ENOMEM on any other error.
250 int omap_prcm_register_chain_handler(struct omap_prcm_irq_setup *irq_setup)
253 u32 mask[OMAP_PRCM_MAX_NR_PENDING_REG];
255 struct irq_chip_generic *gc;
256 struct irq_chip_type *ct;
261 nr_regs = irq_setup->nr_regs;
263 if (prcm_irq_setup) {
264 pr_err("PRCM: already initialized; won't reinitialize\n");
268 if (nr_regs > OMAP_PRCM_MAX_NR_PENDING_REG) {
269 pr_err("PRCM: nr_regs too large\n");
273 prcm_irq_setup = irq_setup;
275 prcm_irq_chips = kzalloc(sizeof(void *) * nr_regs, GFP_KERNEL);
276 prcm_irq_setup->saved_mask = kzalloc(sizeof(u32) * nr_regs, GFP_KERNEL);
277 prcm_irq_setup->priority_mask = kzalloc(sizeof(u32) * nr_regs,
280 if (!prcm_irq_chips || !prcm_irq_setup->saved_mask ||
281 !prcm_irq_setup->priority_mask) {
282 pr_err("PRCM: kzalloc failed\n");
286 memset(mask, 0, sizeof(mask));
288 for (i = 0; i < irq_setup->nr_irqs; i++) {
289 offset = irq_setup->irqs[i].offset;
290 mask[offset >> 5] |= 1 << (offset & 0x1f);
291 if (irq_setup->irqs[i].priority)
292 irq_setup->priority_mask[offset >> 5] |=
293 1 << (offset & 0x1f);
296 irq_set_chained_handler(irq_setup->irq, omap_prcm_irq_handler);
298 irq_setup->base_irq = irq_alloc_descs(-1, 0, irq_setup->nr_regs * 32,
301 if (irq_setup->base_irq < 0) {
302 pr_err("PRCM: failed to allocate irq descs: %d\n",
303 irq_setup->base_irq);
307 for (i = 0; i < irq_setup->nr_regs; i++) {
308 gc = irq_alloc_generic_chip("PRCM", 1,
309 irq_setup->base_irq + i * 32, prm_base,
313 pr_err("PRCM: failed to allocate generic chip\n");
317 ct->chip.irq_ack = irq_gc_ack_set_bit;
318 ct->chip.irq_mask = irq_gc_mask_clr_bit;
319 ct->chip.irq_unmask = irq_gc_mask_set_bit;
321 ct->regs.ack = irq_setup->ack + i * 4;
322 ct->regs.mask = irq_setup->mask + i * 4;
324 irq_setup_generic_chip(gc, mask[i], 0, IRQ_NOREQUEST, 0);
325 prcm_irq_chips[i] = gc;
331 omap_prcm_irq_cleanup();
336 * omap2_set_globals_prm - set the PRM base address (for early use)
337 * @prm: PRM base virtual address
339 * XXX Will be replaced when the PRM/CM drivers are completed.
341 void __init omap2_set_globals_prm(void __iomem *prm)
347 * prm_read_reset_sources - return the sources of the SoC's last reset
349 * Return a u32 bitmask representing the reset sources that caused the
350 * SoC to reset. The low-level per-SoC functions called by this
351 * function remap the SoC-specific reset source bits into an
352 * OMAP-common set of reset source bits, defined in
353 * arch/arm/mach-omap2/prm.h. Returns the standardized reset source
354 * u32 bitmask from the hardware upon success, or returns (1 <<
355 * OMAP_UNKNOWN_RST_SRC_ID_SHIFT) if no low-level read_reset_sources()
356 * function was registered.
358 u32 prm_read_reset_sources(void)
360 u32 ret = 1 << OMAP_UNKNOWN_RST_SRC_ID_SHIFT;
362 if (prm_ll_data->read_reset_sources)
363 ret = prm_ll_data->read_reset_sources();
365 WARN_ONCE(1, "prm: %s: no mapping function defined for reset sources\n", __func__);
371 * prm_register - register per-SoC low-level data with the PRM
372 * @pld: low-level per-SoC OMAP PRM data & function pointers to register
374 * Register per-SoC low-level OMAP PRM data and function pointers with
375 * the OMAP PRM common interface. The caller must keep the data
376 * pointed to by @pld valid until it calls prm_unregister() and
377 * it returns successfully. Returns 0 upon success, -EINVAL if @pld
378 * is NULL, or -EEXIST if prm_register() has already been called
379 * without an intervening prm_unregister().
381 int prm_register(struct prm_ll_data *pld)
386 if (prm_ll_data != &null_prm_ll_data)
395 * prm_unregister - unregister per-SoC low-level data & function pointers
396 * @pld: low-level per-SoC OMAP PRM data & function pointers to unregister
398 * Unregister per-SoC low-level OMAP PRM data and function pointers
399 * that were previously registered with prm_register(). The
400 * caller may not destroy any of the data pointed to by @pld until
401 * this function returns successfully. Returns 0 upon success, or
402 * -EINVAL if @pld is NULL or if @pld does not match the struct
403 * prm_ll_data * previously registered by prm_register().
405 int prm_unregister(struct prm_ll_data *pld)
407 if (!pld || prm_ll_data != pld)
410 prm_ll_data = &null_prm_ll_data;