| /* |
| * Support for C64x+ Megamodule Interrupt Controller |
| * |
| * Copyright (C) 2010, 2011 Texas Instruments Incorporated |
| * Contributed by: Mark Salter <msalter@redhat.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. |
| */ |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/of.h> |
| #include <linux/of_irq.h> |
| #include <linux/of_address.h> |
| #include <linux/slab.h> |
| #include <asm/soc.h> |
| #include <asm/megamod-pic.h> |
| |
| #define NR_COMBINERS 4 |
| #define NR_MUX_OUTPUTS 12 |
| |
| #define IRQ_UNMAPPED 0xffff |
| |
| /* |
| * Megamodule Interrupt Controller register layout |
| */ |
| struct megamod_regs { |
| u32 evtflag[8]; |
| u32 evtset[8]; |
| u32 evtclr[8]; |
| u32 reserved0[8]; |
| u32 evtmask[8]; |
| u32 mevtflag[8]; |
| u32 expmask[8]; |
| u32 mexpflag[8]; |
| u32 intmux_unused; |
| u32 intmux[7]; |
| u32 reserved1[8]; |
| u32 aegmux[2]; |
| u32 reserved2[14]; |
| u32 intxstat; |
| u32 intxclr; |
| u32 intdmask; |
| u32 reserved3[13]; |
| u32 evtasrt; |
| }; |
| |
| struct megamod_pic { |
| struct irq_host *irqhost; |
| struct megamod_regs __iomem *regs; |
| raw_spinlock_t lock; |
| |
| /* hw mux mapping */ |
| unsigned int output_to_irq[NR_MUX_OUTPUTS]; |
| }; |
| |
| static struct megamod_pic *mm_pic; |
| |
| struct megamod_cascade_data { |
| struct megamod_pic *pic; |
| int index; |
| }; |
| |
| static struct megamod_cascade_data cascade_data[NR_COMBINERS]; |
| |
| static void mask_megamod(struct irq_data *data) |
| { |
| struct megamod_pic *pic = irq_data_get_irq_chip_data(data); |
| irq_hw_number_t src = irqd_to_hwirq(data); |
| u32 __iomem *evtmask = &pic->regs->evtmask[src / 32]; |
| |
| raw_spin_lock(&pic->lock); |
| soc_writel(soc_readl(evtmask) | (1 << (src & 31)), evtmask); |
| raw_spin_unlock(&pic->lock); |
| } |
| |
| static void unmask_megamod(struct irq_data *data) |
| { |
| struct megamod_pic *pic = irq_data_get_irq_chip_data(data); |
| irq_hw_number_t src = irqd_to_hwirq(data); |
| u32 __iomem *evtmask = &pic->regs->evtmask[src / 32]; |
| |
| raw_spin_lock(&pic->lock); |
| soc_writel(soc_readl(evtmask) & ~(1 << (src & 31)), evtmask); |
| raw_spin_unlock(&pic->lock); |
| } |
| |
| static struct irq_chip megamod_chip = { |
| .name = "megamod", |
| .irq_mask = mask_megamod, |
| .irq_unmask = unmask_megamod, |
| }; |
| |
| static void megamod_irq_cascade(unsigned int irq, struct irq_desc *desc) |
| { |
| struct megamod_cascade_data *cascade; |
| struct megamod_pic *pic; |
| u32 events; |
| int n, idx; |
| |
| cascade = irq_desc_get_handler_data(desc); |
| |
| pic = cascade->pic; |
| idx = cascade->index; |
| |
| while ((events = soc_readl(&pic->regs->mevtflag[idx])) != 0) { |
| n = __ffs(events); |
| |
| irq = irq_linear_revmap(pic->irqhost, idx * 32 + n); |
| |
| soc_writel(1 << n, &pic->regs->evtclr[idx]); |
| |
| generic_handle_irq(irq); |
| } |
| } |
| |
| static int megamod_map(struct irq_host *h, unsigned int virq, |
| irq_hw_number_t hw) |
| { |
| struct megamod_pic *pic = h->host_data; |
| int i; |
| |
| /* We shouldn't see a hwirq which is muxed to core controller */ |
| for (i = 0; i < NR_MUX_OUTPUTS; i++) |
| if (pic->output_to_irq[i] == hw) |
| return -1; |
| |
| irq_set_chip_data(virq, pic); |
| irq_set_chip_and_handler(virq, &megamod_chip, handle_level_irq); |
| |
| /* Set default irq type */ |
| irq_set_irq_type(virq, IRQ_TYPE_NONE); |
| |
| return 0; |
| } |
| |
| static int megamod_xlate(struct irq_host *h, struct device_node *ct, |
| const u32 *intspec, unsigned int intsize, |
| irq_hw_number_t *out_hwirq, unsigned int *out_type) |
| |
| { |
| /* megamod intspecs must have 1 cell */ |
| BUG_ON(intsize != 1); |
| *out_hwirq = intspec[0]; |
| *out_type = IRQ_TYPE_NONE; |
| return 0; |
| } |
| |
| static struct irq_host_ops megamod_host_ops = { |
| .map = megamod_map, |
| .xlate = megamod_xlate, |
| }; |
| |
| static void __init set_megamod_mux(struct megamod_pic *pic, int src, int output) |
| { |
| int index, offset; |
| u32 val; |
| |
| if (src < 0 || src >= (NR_COMBINERS * 32)) { |
| pic->output_to_irq[output] = IRQ_UNMAPPED; |
| return; |
| } |
| |
| /* four mappings per mux register */ |
| index = output / 4; |
| offset = (output & 3) * 8; |
| |
| val = soc_readl(&pic->regs->intmux[index]); |
| val &= ~(0xff << offset); |
| val |= src << offset; |
| soc_writel(val, &pic->regs->intmux[index]); |
| } |
| |
| /* |
| * Parse the MUX mapping, if one exists. |
| * |
| * The MUX map is an array of up to 12 cells; one for each usable core priority |
| * interrupt. The value of a given cell is the megamodule interrupt source |
| * which is to me MUXed to the output corresponding to the cell position |
| * withing the array. The first cell in the array corresponds to priority |
| * 4 and the last (12th) cell corresponds to priority 15. The allowed |
| * values are 4 - ((NR_COMBINERS * 32) - 1). Note that the combined interrupt |
| * sources (0 - 3) are not allowed to be mapped through this property. They |
| * are handled through the "interrupts" property. This allows us to use a |
| * value of zero as a "do not map" placeholder. |
| */ |
| static void __init parse_priority_map(struct megamod_pic *pic, |
| int *mapping, int size) |
| { |
| struct device_node *np = pic->irqhost->of_node; |
| const __be32 *map; |
| int i, maplen; |
| u32 val; |
| |
| map = of_get_property(np, "ti,c64x+megamod-pic-mux", &maplen); |
| if (map) { |
| maplen /= 4; |
| if (maplen > size) |
| maplen = size; |
| |
| for (i = 0; i < maplen; i++) { |
| val = be32_to_cpup(map); |
| if (val && val >= 4) |
| mapping[i] = val; |
| ++map; |
| } |
| } |
| } |
| |
| static struct megamod_pic * __init init_megamod_pic(struct device_node *np) |
| { |
| struct megamod_pic *pic; |
| int i, irq; |
| int mapping[NR_MUX_OUTPUTS]; |
| |
| pr_info("Initializing C64x+ Megamodule PIC\n"); |
| |
| pic = kzalloc(sizeof(struct megamod_pic), GFP_KERNEL); |
| if (!pic) { |
| pr_err("%s: Could not alloc PIC structure.\n", np->full_name); |
| return NULL; |
| } |
| |
| pic->irqhost = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, |
| NR_COMBINERS * 32, &megamod_host_ops, |
| IRQ_UNMAPPED); |
| if (!pic->irqhost) { |
| pr_err("%s: Could not alloc host.\n", np->full_name); |
| goto error_free; |
| } |
| |
| pic->irqhost->host_data = pic; |
| |
| raw_spin_lock_init(&pic->lock); |
| |
| pic->regs = of_iomap(np, 0); |
| if (!pic->regs) { |
| pr_err("%s: Could not map registers.\n", np->full_name); |
| goto error_free; |
| } |
| |
| /* Initialize MUX map */ |
| for (i = 0; i < ARRAY_SIZE(mapping); i++) |
| mapping[i] = IRQ_UNMAPPED; |
| |
| parse_priority_map(pic, mapping, ARRAY_SIZE(mapping)); |
| |
| /* |
| * We can have up to 12 interrupts cascading to the core controller. |
| * These cascades can be from the combined interrupt sources or for |
| * individual interrupt sources. The "interrupts" property only |
| * deals with the cascaded combined interrupts. The individual |
| * interrupts muxed to the core controller use the core controller |
| * as their interrupt parent. |
| */ |
| for (i = 0; i < NR_COMBINERS; i++) { |
| |
| irq = irq_of_parse_and_map(np, i); |
| if (irq == NO_IRQ) |
| continue; |
| |
| /* |
| * We count on the core priority interrupts (4 - 15) being |
| * direct mapped. Check that device tree provided something |
| * in that range. |
| */ |
| if (irq < 4 || irq >= NR_PRIORITY_IRQS) { |
| pr_err("%s: combiner-%d virq %d out of range!\n", |
| np->full_name, i, irq); |
| continue; |
| } |
| |
| /* record the mapping */ |
| mapping[irq - 4] = i; |
| |
| pr_debug("%s: combiner-%d cascading to virq %d\n", |
| np->full_name, i, irq); |
| |
| cascade_data[i].pic = pic; |
| cascade_data[i].index = i; |
| |
| /* mask and clear all events in combiner */ |
| soc_writel(~0, &pic->regs->evtmask[i]); |
| soc_writel(~0, &pic->regs->evtclr[i]); |
| |
| irq_set_handler_data(irq, &cascade_data[i]); |
| irq_set_chained_handler(irq, megamod_irq_cascade); |
| } |
| |
| /* Finally, set up the MUX registers */ |
| for (i = 0; i < NR_MUX_OUTPUTS; i++) { |
| if (mapping[i] != IRQ_UNMAPPED) { |
| pr_debug("%s: setting mux %d to priority %d\n", |
| np->full_name, mapping[i], i + 4); |
| set_megamod_mux(pic, mapping[i], i); |
| } |
| } |
| |
| return pic; |
| |
| error_free: |
| kfree(pic); |
| |
| return NULL; |
| } |
| |
| /* |
| * Return next active event after ACK'ing it. |
| * Return -1 if no events active. |
| */ |
| static int get_exception(void) |
| { |
| int i, bit; |
| u32 mask; |
| |
| for (i = 0; i < NR_COMBINERS; i++) { |
| mask = soc_readl(&mm_pic->regs->mexpflag[i]); |
| if (mask) { |
| bit = __ffs(mask); |
| soc_writel(1 << bit, &mm_pic->regs->evtclr[i]); |
| return (i * 32) + bit; |
| } |
| } |
| return -1; |
| } |
| |
| static void assert_event(unsigned int val) |
| { |
| soc_writel(val, &mm_pic->regs->evtasrt); |
| } |
| |
| void __init megamod_pic_init(void) |
| { |
| struct device_node *np; |
| |
| np = of_find_compatible_node(NULL, NULL, "ti,c64x+megamod-pic"); |
| if (!np) |
| return; |
| |
| mm_pic = init_megamod_pic(np); |
| of_node_put(np); |
| |
| soc_ops.get_exception = get_exception; |
| soc_ops.assert_event = assert_event; |
| |
| return; |
| } |