| /* |
| * OMAP2+ common Power & Reset Management (PRM) IP block functions |
| * |
| * Copyright (C) 2011 Texas Instruments, Inc. |
| * Tero Kristo <t-kristo@ti.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * |
| * For historical purposes, the API used to configure the PRM |
| * interrupt handler refers to it as the "PRCM interrupt." The |
| * underlying registers are located in the PRM on OMAP3/4. |
| * |
| * XXX This code should eventually be moved to a PRM driver. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/io.h> |
| #include <linux/irq.h> |
| #include <linux/interrupt.h> |
| #include <linux/slab.h> |
| |
| #include <plat/common.h> |
| #include <plat/prcm.h> |
| #include <plat/irqs.h> |
| |
| #include "prm2xxx_3xxx.h" |
| #include "prm44xx.h" |
| |
| /* |
| * OMAP_PRCM_MAX_NR_PENDING_REG: maximum number of PRM_IRQ*_MPU regs |
| * XXX this is technically not needed, since |
| * omap_prcm_register_chain_handler() could allocate this based on the |
| * actual amount of memory needed for the SoC |
| */ |
| #define OMAP_PRCM_MAX_NR_PENDING_REG 2 |
| |
| /* |
| * prcm_irq_chips: an array of all of the "generic IRQ chips" in use |
| * by the PRCM interrupt handler code. There will be one 'chip' per |
| * PRM_{IRQSTATUS,IRQENABLE}_MPU register pair. (So OMAP3 will have |
| * one "chip" and OMAP4 will have two.) |
| */ |
| static struct irq_chip_generic **prcm_irq_chips; |
| |
| /* |
| * prcm_irq_setup: the PRCM IRQ parameters for the hardware the code |
| * is currently running on. Defined and passed by initialization code |
| * that calls omap_prcm_register_chain_handler(). |
| */ |
| static struct omap_prcm_irq_setup *prcm_irq_setup; |
| |
| /* Private functions */ |
| |
| /* |
| * Move priority events from events to priority_events array |
| */ |
| static void omap_prcm_events_filter_priority(unsigned long *events, |
| unsigned long *priority_events) |
| { |
| int i; |
| |
| for (i = 0; i < prcm_irq_setup->nr_regs; i++) { |
| priority_events[i] = |
| events[i] & prcm_irq_setup->priority_mask[i]; |
| events[i] ^= priority_events[i]; |
| } |
| } |
| |
| /* |
| * PRCM Interrupt Handler |
| * |
| * This is a common handler for the OMAP PRCM interrupts. Pending |
| * interrupts are detected by a call to prcm_pending_events and |
| * dispatched accordingly. Clearing of the wakeup events should be |
| * done by the SoC specific individual handlers. |
| */ |
| static void omap_prcm_irq_handler(unsigned int irq, struct irq_desc *desc) |
| { |
| unsigned long pending[OMAP_PRCM_MAX_NR_PENDING_REG]; |
| unsigned long priority_pending[OMAP_PRCM_MAX_NR_PENDING_REG]; |
| struct irq_chip *chip = irq_desc_get_chip(desc); |
| unsigned int virtirq; |
| int nr_irqs = prcm_irq_setup->nr_regs * 32; |
| |
| /* |
| * If we are suspended, mask all interrupts from PRCM level, |
| * this does not ack them, and they will be pending until we |
| * re-enable the interrupts, at which point the |
| * omap_prcm_irq_handler will be executed again. The |
| * _save_and_clear_irqen() function must ensure that the PRM |
| * write to disable all IRQs has reached the PRM before |
| * returning, or spurious PRCM interrupts may occur during |
| * suspend. |
| */ |
| if (prcm_irq_setup->suspended) { |
| prcm_irq_setup->save_and_clear_irqen(prcm_irq_setup->saved_mask); |
| prcm_irq_setup->suspend_save_flag = true; |
| } |
| |
| /* |
| * Loop until all pending irqs are handled, since |
| * generic_handle_irq() can cause new irqs to come |
| */ |
| while (!prcm_irq_setup->suspended) { |
| prcm_irq_setup->read_pending_irqs(pending); |
| |
| /* No bit set, then all IRQs are handled */ |
| if (find_first_bit(pending, nr_irqs) >= nr_irqs) |
| break; |
| |
| omap_prcm_events_filter_priority(pending, priority_pending); |
| |
| /* |
| * Loop on all currently pending irqs so that new irqs |
| * cannot starve previously pending irqs |
| */ |
| |
| /* Serve priority events first */ |
| for_each_set_bit(virtirq, priority_pending, nr_irqs) |
| generic_handle_irq(prcm_irq_setup->base_irq + virtirq); |
| |
| /* Serve normal events next */ |
| for_each_set_bit(virtirq, pending, nr_irqs) |
| generic_handle_irq(prcm_irq_setup->base_irq + virtirq); |
| } |
| if (chip->irq_ack) |
| chip->irq_ack(&desc->irq_data); |
| if (chip->irq_eoi) |
| chip->irq_eoi(&desc->irq_data); |
| chip->irq_unmask(&desc->irq_data); |
| |
| prcm_irq_setup->ocp_barrier(); /* avoid spurious IRQs */ |
| } |
| |
| /* Public functions */ |
| |
| /** |
| * omap_prcm_event_to_irq - given a PRCM event name, returns the |
| * corresponding IRQ on which the handler should be registered |
| * @name: name of the PRCM interrupt bit to look up - see struct omap_prcm_irq |
| * |
| * Returns the Linux internal IRQ ID corresponding to @name upon success, |
| * or -ENOENT upon failure. |
| */ |
| int omap_prcm_event_to_irq(const char *name) |
| { |
| int i; |
| |
| if (!prcm_irq_setup || !name) |
| return -ENOENT; |
| |
| for (i = 0; i < prcm_irq_setup->nr_irqs; i++) |
| if (!strcmp(prcm_irq_setup->irqs[i].name, name)) |
| return prcm_irq_setup->base_irq + |
| prcm_irq_setup->irqs[i].offset; |
| |
| return -ENOENT; |
| } |
| |
| /** |
| * omap_prcm_irq_cleanup - reverses memory allocated and other steps |
| * done by omap_prcm_register_chain_handler() |
| * |
| * No return value. |
| */ |
| void omap_prcm_irq_cleanup(void) |
| { |
| int i; |
| |
| if (!prcm_irq_setup) { |
| pr_err("PRCM: IRQ handler not initialized; cannot cleanup\n"); |
| return; |
| } |
| |
| if (prcm_irq_chips) { |
| for (i = 0; i < prcm_irq_setup->nr_regs; i++) { |
| if (prcm_irq_chips[i]) |
| irq_remove_generic_chip(prcm_irq_chips[i], |
| 0xffffffff, 0, 0); |
| prcm_irq_chips[i] = NULL; |
| } |
| kfree(prcm_irq_chips); |
| prcm_irq_chips = NULL; |
| } |
| |
| kfree(prcm_irq_setup->saved_mask); |
| prcm_irq_setup->saved_mask = NULL; |
| |
| kfree(prcm_irq_setup->priority_mask); |
| prcm_irq_setup->priority_mask = NULL; |
| |
| irq_set_chained_handler(prcm_irq_setup->irq, NULL); |
| |
| if (prcm_irq_setup->base_irq > 0) |
| irq_free_descs(prcm_irq_setup->base_irq, |
| prcm_irq_setup->nr_regs * 32); |
| prcm_irq_setup->base_irq = 0; |
| } |
| |
| void omap_prcm_irq_prepare(void) |
| { |
| prcm_irq_setup->suspended = true; |
| } |
| |
| void omap_prcm_irq_complete(void) |
| { |
| prcm_irq_setup->suspended = false; |
| |
| /* If we have not saved the masks, do not attempt to restore */ |
| if (!prcm_irq_setup->suspend_save_flag) |
| return; |
| |
| prcm_irq_setup->suspend_save_flag = false; |
| |
| /* |
| * Re-enable all masked PRCM irq sources, this causes the PRCM |
| * interrupt to fire immediately if the events were masked |
| * previously in the chain handler |
| */ |
| prcm_irq_setup->restore_irqen(prcm_irq_setup->saved_mask); |
| } |
| |
| /** |
| * omap_prcm_register_chain_handler - initializes the prcm chained interrupt |
| * handler based on provided parameters |
| * @irq_setup: hardware data about the underlying PRM/PRCM |
| * |
| * Set up the PRCM chained interrupt handler on the PRCM IRQ. Sets up |
| * one generic IRQ chip per PRM interrupt status/enable register pair. |
| * Returns 0 upon success, -EINVAL if called twice or if invalid |
| * arguments are passed, or -ENOMEM on any other error. |
| */ |
| int omap_prcm_register_chain_handler(struct omap_prcm_irq_setup *irq_setup) |
| { |
| int nr_regs = irq_setup->nr_regs; |
| u32 mask[OMAP_PRCM_MAX_NR_PENDING_REG]; |
| int offset, i; |
| struct irq_chip_generic *gc; |
| struct irq_chip_type *ct; |
| |
| if (!irq_setup) |
| return -EINVAL; |
| |
| if (prcm_irq_setup) { |
| pr_err("PRCM: already initialized; won't reinitialize\n"); |
| return -EINVAL; |
| } |
| |
| if (nr_regs > OMAP_PRCM_MAX_NR_PENDING_REG) { |
| pr_err("PRCM: nr_regs too large\n"); |
| return -EINVAL; |
| } |
| |
| prcm_irq_setup = irq_setup; |
| |
| prcm_irq_chips = kzalloc(sizeof(void *) * nr_regs, GFP_KERNEL); |
| prcm_irq_setup->saved_mask = kzalloc(sizeof(u32) * nr_regs, GFP_KERNEL); |
| prcm_irq_setup->priority_mask = kzalloc(sizeof(u32) * nr_regs, |
| GFP_KERNEL); |
| |
| if (!prcm_irq_chips || !prcm_irq_setup->saved_mask || |
| !prcm_irq_setup->priority_mask) { |
| pr_err("PRCM: kzalloc failed\n"); |
| goto err; |
| } |
| |
| memset(mask, 0, sizeof(mask)); |
| |
| for (i = 0; i < irq_setup->nr_irqs; i++) { |
| offset = irq_setup->irqs[i].offset; |
| mask[offset >> 5] |= 1 << (offset & 0x1f); |
| if (irq_setup->irqs[i].priority) |
| irq_setup->priority_mask[offset >> 5] |= |
| 1 << (offset & 0x1f); |
| } |
| |
| irq_set_chained_handler(irq_setup->irq, omap_prcm_irq_handler); |
| |
| irq_setup->base_irq = irq_alloc_descs(-1, 0, irq_setup->nr_regs * 32, |
| 0); |
| |
| if (irq_setup->base_irq < 0) { |
| pr_err("PRCM: failed to allocate irq descs: %d\n", |
| irq_setup->base_irq); |
| goto err; |
| } |
| |
| for (i = 0; i < irq_setup->nr_regs; i++) { |
| gc = irq_alloc_generic_chip("PRCM", 1, |
| irq_setup->base_irq + i * 32, prm_base, |
| handle_level_irq); |
| |
| if (!gc) { |
| pr_err("PRCM: failed to allocate generic chip\n"); |
| goto err; |
| } |
| ct = gc->chip_types; |
| ct->chip.irq_ack = irq_gc_ack_set_bit; |
| ct->chip.irq_mask = irq_gc_mask_clr_bit; |
| ct->chip.irq_unmask = irq_gc_mask_set_bit; |
| |
| ct->regs.ack = irq_setup->ack + i * 4; |
| ct->regs.mask = irq_setup->mask + i * 4; |
| |
| irq_setup_generic_chip(gc, mask[i], 0, IRQ_NOREQUEST, 0); |
| prcm_irq_chips[i] = gc; |
| } |
| |
| return 0; |
| |
| err: |
| omap_prcm_irq_cleanup(); |
| return -ENOMEM; |
| } |