diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-09 14:39:59 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-01-09 14:39:59 -0800 |
commit | b3c37522928b5452588fc202eaa0f11f6e339256 (patch) | |
tree | 37bfe21d9977b15271903d1a4b304289a232e364 /arch/arm/mach-omap2/prm_common.c | |
parent | 2ac9d7aaccbd598b5bd19ac40761b723bb675442 (diff) | |
parent | 6d0a5636fba5a3f82ec80ab124dd4748344549c3 (diff) |
Merge tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
power management changes for omap and imx
A significant part of the changes for these two platforms went into
power management, so they are split out into a separate branch.
* tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (65 commits)
ARM: imx6: remove __CPUINIT annotation from v7_invalidate_l1
ARM: imx6: fix v7_invalidate_l1 by adding I-Cache invalidation
ARM: imx6q: resume PL310 only when CACHE_L2X0 defined
ARM: imx6q: build pm code only when CONFIG_PM selected
ARM: mx5: use generic irq chip pm interface for pm functions on
ARM: omap: pass minimal SoC/board data for UART from dt
arm/dts: Add minimal device tree support for omap2420 and omap2430
omap-serial: Add minimal device tree support
omap-serial: Use default clock speed (48Mhz) if not specified
omap-serial: Get rid of all pdev->id usage
ARM: OMAP2+: hwmod: Add a new flag to handle hwmods left enabled at init
ARM: OMAP4: PRM: use PRCM interrupt handler
ARM: OMAP3: pm: use prcm chain handler
ARM: OMAP: hwmod: add support for selecting mpu_irq for each wakeup pad
ARM: OMAP2+: mux: add support for PAD wakeup interrupts
ARM: OMAP: PRCM: add suspend prepare / finish support
ARM: OMAP: PRCM: add support for chain interrupt handler
ARM: OMAP3/4: PRM: add functions to read pending IRQs, PRM barrier
ARM: OMAP2+: hwmod: Add API to enable IO ring wakeup
ARM: OMAP2+: mux: add wakeup-capable hwmod mux entries to dynamic list
...
Diffstat (limited to 'arch/arm/mach-omap2/prm_common.c')
-rw-r--r-- | arch/arm/mach-omap2/prm_common.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/prm_common.c b/arch/arm/mach-omap2/prm_common.c new file mode 100644 index 000000000000..860118ab43e2 --- /dev/null +++ b/arch/arm/mach-omap2/prm_common.c @@ -0,0 +1,320 @@ +/* + * 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 <mach/system.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; +} |