--- /dev/null
+/*
+ * Cristian Birsan <cristian.birsan@microchip.com>
+ * Joshua Henderson <joshua.henderson@microchip.com>
+ * Copyright (C) 2016 Microchip Technology Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irq.h>
+
+#include <asm/irq.h>
+#include <asm/traps.h>
+#include <asm/mach-pic32/pic32.h>
+
+#define REG_INTCON 0x0000
+#define REG_INTSTAT 0x0020
+#define REG_IFS_OFFSET 0x0040
+#define REG_IEC_OFFSET 0x00C0
+#define REG_IPC_OFFSET 0x0140
+#define REG_OFF_OFFSET 0x0540
+
+#define MAJPRI_MASK 0x07
+#define SUBPRI_MASK 0x03
+#define PRIORITY_MASK 0x1F
+
+#define PIC32_INT_PRI(pri, subpri) \
+ ((((pri) & MAJPRI_MASK) << 2) | ((subpri) & SUBPRI_MASK))
+
+struct evic_chip_data {
+ u32 irq_types[NR_IRQS];
+ u32 ext_irqs[8];
+};
+
+static struct irq_domain *evic_irq_domain;
+static void __iomem *evic_base;
+
+asmlinkage void __weak plat_irq_dispatch(void)
+{
+ unsigned int irq, hwirq;
+
+ hwirq = readl(evic_base + REG_INTSTAT) & 0xFF;
+ irq = irq_linear_revmap(evic_irq_domain, hwirq);
+ do_IRQ(irq);
+}
+
+static struct evic_chip_data *irqd_to_priv(struct irq_data *data)
+{
+ return (struct evic_chip_data *)data->domain->host_data;
+}
+
+static int pic32_set_ext_polarity(int bit, u32 type)
+{
+ /*
+ * External interrupts can be either edge rising or edge falling,
+ * but not both.
+ */
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ writel(BIT(bit), evic_base + PIC32_SET(REG_INTCON));
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ writel(BIT(bit), evic_base + PIC32_CLR(REG_INTCON));
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int pic32_set_type_edge(struct irq_data *data,
+ unsigned int flow_type)
+{
+ struct evic_chip_data *priv = irqd_to_priv(data);
+ int ret;
+ int i;
+
+ if (!(flow_type & IRQ_TYPE_EDGE_BOTH))
+ return -EBADR;
+
+ /* set polarity for external interrupts only */
+ for (i = 0; i < ARRAY_SIZE(priv->ext_irqs); i++) {
+ if (priv->ext_irqs[i] == data->hwirq) {
+ ret = pic32_set_ext_polarity(i + 1, flow_type);
+ if (ret)
+ return ret;
+ }
+ }
+
+ irqd_set_trigger_type(data, flow_type);
+
+ return IRQ_SET_MASK_OK;
+}
+
+static void pic32_bind_evic_interrupt(int irq, int set)
+{
+ writel(set, evic_base + REG_OFF_OFFSET + irq * 4);
+}
+
+static void pic32_set_irq_priority(int irq, int priority)
+{
+ u32 reg, shift;
+
+ reg = irq / 4;
+ shift = (irq % 4) * 8;
+
+ writel(PRIORITY_MASK << shift,
+ evic_base + PIC32_CLR(REG_IPC_OFFSET + reg * 0x10));
+ writel(priority << shift,
+ evic_base + PIC32_SET(REG_IPC_OFFSET + reg * 0x10));
+}
+
+#define IRQ_REG_MASK(_hwirq, _reg, _mask) \
+ do { \
+ _reg = _hwirq / 32; \
+ _mask = 1 << (_hwirq % 32); \
+ } while (0)
+
+static int pic32_irq_domain_map(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ struct evic_chip_data *priv = d->host_data;
+ struct irq_data *data;
+ int ret;
+ u32 iecclr, ifsclr;
+ u32 reg, mask;
+
+ ret = irq_map_generic_chip(d, virq, hw);
+ if (ret)
+ return ret;
+
+ /*
+ * Piggyback on xlate function to move to an alternate chip as necessary
+ * at time of mapping instead of allowing the flow handler/chip to be
+ * changed later. This requires all interrupts to be configured through
+ * DT.
+ */
+ if (priv->irq_types[hw] & IRQ_TYPE_SENSE_MASK) {
+ data = irq_domain_get_irq_data(d, virq);
+ irqd_set_trigger_type(data, priv->irq_types[hw]);
+ irq_setup_alt_chip(data, priv->irq_types[hw]);
+ }
+
+ IRQ_REG_MASK(hw, reg, mask);
+
+ iecclr = PIC32_CLR(REG_IEC_OFFSET + reg * 0x10);
+ ifsclr = PIC32_CLR(REG_IFS_OFFSET + reg * 0x10);
+
+ /* mask and clear flag */
+ writel(mask, evic_base + iecclr);
+ writel(mask, evic_base + ifsclr);
+
+ /* default priority is required */
+ pic32_set_irq_priority(hw, PIC32_INT_PRI(2, 0));
+
+ return ret;
+}
+
+int pic32_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
+ const u32 *intspec, unsigned int intsize,
+ irq_hw_number_t *out_hwirq, unsigned int *out_type)
+{
+ struct evic_chip_data *priv = d->host_data;
+
+ if (WARN_ON(intsize < 2))
+ return -EINVAL;
+
+ if (WARN_ON(intspec[0] >= NR_IRQS))
+ return -EINVAL;
+
+ *out_hwirq = intspec[0];
+ *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
+
+ priv->irq_types[intspec[0]] = intspec[1] & IRQ_TYPE_SENSE_MASK;
+
+ return 0;
+}
+
+static const struct irq_domain_ops pic32_irq_domain_ops = {
+ .map = pic32_irq_domain_map,
+ .xlate = pic32_irq_domain_xlate,
+};
+
+static void __init pic32_ext_irq_of_init(struct irq_domain *domain)
+{
+ struct device_node *node = irq_domain_get_of_node(domain);
+ struct evic_chip_data *priv = domain->host_data;
+ struct property *prop;
+ const __le32 *p;
+ u32 hwirq;
+ int i = 0;
+ const char *pname = "microchip,external-irqs";
+
+ of_property_for_each_u32(node, pname, prop, p, hwirq) {
+ if (i >= ARRAY_SIZE(priv->ext_irqs)) {
+ pr_warn("More than %d external irq, skip rest\n",
+ ARRAY_SIZE(priv->ext_irqs));
+ break;
+ }
+
+ priv->ext_irqs[i] = hwirq;
+ i++;
+ }
+}
+
+static int __init pic32_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ struct irq_chip_generic *gc;
+ struct evic_chip_data *priv;
+ unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+ int nchips, ret;
+ int i;
+
+ nchips = DIV_ROUND_UP(NR_IRQS, 32);
+
+ evic_base = of_iomap(node, 0);
+ if (!evic_base)
+ return -ENOMEM;
+
+ priv = kcalloc(nchips, sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto err_iounmap;
+ }
+
+ evic_irq_domain = irq_domain_add_linear(node, nchips * 32,
+ &pic32_irq_domain_ops,
+ priv);
+ if (!evic_irq_domain) {
+ ret = -ENOMEM;
+ goto err_free_priv;
+ }
+
+ /*
+ * The PIC32 EVIC has a linear list of irqs and the type of each
+ * irq is determined by the hardware peripheral the EVIC is arbitrating.
+ * These irq types are defined in the datasheet as "persistent" and
+ * "non-persistent" which are mapped here to level and edge
+ * respectively. To manage the different flow handler requirements of
+ * each irq type, different chip_types are used.
+ */
+ ret = irq_alloc_domain_generic_chips(evic_irq_domain, 32, 2,
+ "evic-level", handle_level_irq,
+ clr, 0, 0);
+ if (ret)
+ goto err_domain_remove;
+
+ board_bind_eic_interrupt = &pic32_bind_evic_interrupt;
+
+ for (i = 0; i < nchips; i++) {
+ u32 ifsclr = PIC32_CLR(REG_IFS_OFFSET + (i * 0x10));
+ u32 iec = REG_IEC_OFFSET + (i * 0x10);
+
+ gc = irq_get_domain_generic_chip(evic_irq_domain, i * 32);
+
+ gc->reg_base = evic_base;
+ gc->unused = 0;
+
+ /*
+ * Level/persistent interrupts have a special requirement that
+ * the condition generating the interrupt be cleared before the
+ * interrupt flag (ifs) can be cleared. chip.irq_eoi is used to
+ * complete the interrupt with an ack.
+ */
+ gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
+ gc->chip_types[0].handler = handle_fasteoi_irq;
+ gc->chip_types[0].regs.ack = ifsclr;
+ gc->chip_types[0].regs.mask = iec;
+ gc->chip_types[0].chip.name = "evic-level";
+ gc->chip_types[0].chip.irq_eoi = irq_gc_ack_set_bit;
+ gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
+ gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
+ gc->chip_types[0].chip.flags = IRQCHIP_SKIP_SET_WAKE;
+
+ /* Edge interrupts */
+ gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
+ gc->chip_types[1].handler = handle_edge_irq;
+ gc->chip_types[1].regs.ack = ifsclr;
+ gc->chip_types[1].regs.mask = iec;
+ gc->chip_types[1].chip.name = "evic-edge";
+ gc->chip_types[1].chip.irq_ack = irq_gc_ack_set_bit;
+ gc->chip_types[1].chip.irq_mask = irq_gc_mask_clr_bit;
+ gc->chip_types[1].chip.irq_unmask = irq_gc_mask_set_bit;
+ gc->chip_types[1].chip.irq_set_type = pic32_set_type_edge;
+ gc->chip_types[1].chip.flags = IRQCHIP_SKIP_SET_WAKE;
+
+ gc->private = &priv[i];
+ }
+
+ irq_set_default_host(evic_irq_domain);
+
+ /*
+ * External interrupts have software configurable edge polarity. These
+ * interrupts are defined in DT allowing polarity to be configured only
+ * for these interrupts when requested.
+ */
+ pic32_ext_irq_of_init(evic_irq_domain);
+
+ return 0;
+
+err_domain_remove:
+ irq_domain_remove(evic_irq_domain);
+
+err_free_priv:
+ kfree(priv);
+
+err_iounmap:
+ iounmap(evic_base);
+
+ return ret;
+}
+
+IRQCHIP_DECLARE(pic32_evic, "microchip,pic32mzda-evic", pic32_of_init);
projects / linux-drm-fsl-dcu.git / commitdiff