LXR linux/drivers/irqchip/irq-mxs.c

   1/*
   2 * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
   3 * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
   4 *      Add Alphascale ASM9260 support.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License along
  17 * with this program; if not, write to the Free Software Foundation, Inc.,
  18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19 */
  20
  21#include <linux/kernel.h>
  22#include <linux/init.h>
  23#include <linux/irq.h>
  24#include <linux/irqchip.h>
  25#include <linux/irqdomain.h>
  26#include <linux/io.h>
  27#include <linux/of.h>
  28#include <linux/of_address.h>
  29#include <linux/of_irq.h>
  30#include <linux/stmp_device.h>
  31#include <asm/exception.h>
  32
  33#include "alphascale_asm9260-icoll.h"
  34
  35/*
  36 * this device provide 4 offsets for each register:
  37 * 0x0 - plain read write mode
  38 * 0x4 - set mode, OR logic.
  39 * 0x8 - clr mode, XOR logic.
  40 * 0xc - togle mode.
  41 */
  42#define SET_REG 4
  43#define CLR_REG 8
  44
  45#define HW_ICOLL_VECTOR                         0x0000
  46#define HW_ICOLL_LEVELACK                       0x0010
  47#define HW_ICOLL_CTRL                           0x0020
  48#define HW_ICOLL_STAT_OFFSET                    0x0070
  49#define HW_ICOLL_INTERRUPT0                     0x0120
  50#define HW_ICOLL_INTERRUPTn(n)                  ((n) * 0x10)
  51#define BM_ICOLL_INTR_ENABLE                    BIT(2)
  52#define BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0   0x1
  53
  54#define ICOLL_NUM_IRQS          128
  55
  56enum icoll_type {
  57        ICOLL,
  58        ASM9260_ICOLL,
  59};
  60
  61struct icoll_priv {
  62        void __iomem *vector;
  63        void __iomem *levelack;
  64        void __iomem *ctrl;
  65        void __iomem *stat;
  66        void __iomem *intr;
  67        void __iomem *clear;
  68        enum icoll_type type;
  69};
  70
  71static struct icoll_priv icoll_priv;
  72static struct irq_domain *icoll_domain;
  73
  74/* calculate bit offset depending on number of intterupt per register */
  75static u32 icoll_intr_bitshift(struct irq_data *d, u32 bit)
  76{
  77        /*
  78         * mask lower part of hwirq to convert it
  79         * in 0, 1, 2 or 3 and then multiply it by 8 (or shift by 3)
  80         */
  81        return bit << ((d->hwirq & 3) << 3);
  82}
  83
  84/* calculate mem offset depending on number of intterupt per register */
  85static void __iomem *icoll_intr_reg(struct irq_data *d)
  86{
  87        /* offset = hwirq / intr_per_reg * 0x10 */
  88        return icoll_priv.intr + ((d->hwirq >> 2) * 0x10);
  89}
  90
  91static void icoll_ack_irq(struct irq_data *d)
  92{
  93        /*
  94         * The Interrupt Collector is able to prioritize irqs.
  95         * Currently only level 0 is used. So acking can use
  96         * BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0 unconditionally.
  97         */
  98        __raw_writel(BV_ICOLL_LEVELACK_IRQLEVELACK__LEVEL0,
  99                        icoll_priv.levelack);
 100}
 101
 102static void icoll_mask_irq(struct irq_data *d)
 103{
 104        __raw_writel(BM_ICOLL_INTR_ENABLE,
 105                        icoll_priv.intr + CLR_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
 106}
 107
 108static void icoll_unmask_irq(struct irq_data *d)
 109{
 110        __raw_writel(BM_ICOLL_INTR_ENABLE,
 111                        icoll_priv.intr + SET_REG + HW_ICOLL_INTERRUPTn(d->hwirq));
 112}
 113
 114static void asm9260_mask_irq(struct irq_data *d)
 115{
 116        __raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
 117                        icoll_intr_reg(d) + CLR_REG);
 118}
 119
 120static void asm9260_unmask_irq(struct irq_data *d)
 121{
 122        __raw_writel(ASM9260_BM_CLEAR_BIT(d->hwirq),
 123                     icoll_priv.clear +
 124                     ASM9260_HW_ICOLL_CLEARn(d->hwirq));
 125
 126        __raw_writel(icoll_intr_bitshift(d, BM_ICOLL_INTR_ENABLE),
 127                        icoll_intr_reg(d) + SET_REG);
 128}
 129
 130static struct irq_chip mxs_icoll_chip = {
 131        .irq_ack = icoll_ack_irq,
 132        .irq_mask = icoll_mask_irq,
 133        .irq_unmask = icoll_unmask_irq,
 134        .flags = IRQCHIP_MASK_ON_SUSPEND |
 135                 IRQCHIP_SKIP_SET_WAKE,
 136};
 137
 138static struct irq_chip asm9260_icoll_chip = {
 139        .irq_ack = icoll_ack_irq,
 140        .irq_mask = asm9260_mask_irq,
 141        .irq_unmask = asm9260_unmask_irq,
 142        .flags = IRQCHIP_MASK_ON_SUSPEND |
 143                 IRQCHIP_SKIP_SET_WAKE,
 144};
 145
 146asmlinkage void __exception_irq_entry icoll_handle_irq(struct pt_regs *regs)
 147{
 148        u32 irqnr;
 149
 150        irqnr = __raw_readl(icoll_priv.stat);
 151        __raw_writel(irqnr, icoll_priv.vector);
 152        handle_domain_irq(icoll_domain, irqnr, regs);
 153}
 154
 155static int icoll_irq_domain_map(struct irq_domain *d, unsigned int virq,
 156                                irq_hw_number_t hw)
 157{
 158        struct irq_chip *chip;
 159
 160        if (icoll_priv.type == ICOLL)
 161                chip = &mxs_icoll_chip;
 162        else
 163                chip = &asm9260_icoll_chip;
 164
 165        irq_set_chip_and_handler(virq, chip, handle_level_irq);
 166
 167        return 0;
 168}
 169
 170static const struct irq_domain_ops icoll_irq_domain_ops = {
 171        .map = icoll_irq_domain_map,
 172        .xlate = irq_domain_xlate_onecell,
 173};
 174
 175static void __init icoll_add_domain(struct device_node *np,
 176                          int num)
 177{
 178        icoll_domain = irq_domain_add_linear(np, num,
 179                                             &icoll_irq_domain_ops, NULL);
 180
 181        if (!icoll_domain)
 182                panic("%s: unable to create irq domain", np->full_name);
 183}
 184
 185static void __iomem * __init icoll_init_iobase(struct device_node *np)
 186{
 187        void __iomem *icoll_base;
 188
 189        icoll_base = of_io_request_and_map(np, 0, np->name);
 190        if (IS_ERR(icoll_base))
 191                panic("%s: unable to map resource", np->full_name);
 192        return icoll_base;
 193}
 194
 195static int __init icoll_of_init(struct device_node *np,
 196                          struct device_node *interrupt_parent)
 197{
 198        void __iomem *icoll_base;
 199
 200        icoll_priv.type = ICOLL;
 201
 202        icoll_base              = icoll_init_iobase(np);
 203        icoll_priv.vector       = icoll_base + HW_ICOLL_VECTOR;
 204        icoll_priv.levelack     = icoll_base + HW_ICOLL_LEVELACK;
 205        icoll_priv.ctrl         = icoll_base + HW_ICOLL_CTRL;
 206        icoll_priv.stat         = icoll_base + HW_ICOLL_STAT_OFFSET;
 207        icoll_priv.intr         = icoll_base + HW_ICOLL_INTERRUPT0;
 208        icoll_priv.clear        = NULL;
 209
 210        /*
 211         * Interrupt Collector reset, which initializes the priority
 212         * for each irq to level 0.
 213         */
 214        stmp_reset_block(icoll_priv.ctrl);
 215
 216        icoll_add_domain(np, ICOLL_NUM_IRQS);
 217
 218        return 0;
 219}
 220IRQCHIP_DECLARE(mxs, "fsl,icoll", icoll_of_init);
 221
 222static int __init asm9260_of_init(struct device_node *np,
 223                          struct device_node *interrupt_parent)
 224{
 225        void __iomem *icoll_base;
 226        int i;
 227
 228        icoll_priv.type = ASM9260_ICOLL;
 229
 230        icoll_base = icoll_init_iobase(np);
 231        icoll_priv.vector       = icoll_base + ASM9260_HW_ICOLL_VECTOR;
 232        icoll_priv.levelack     = icoll_base + ASM9260_HW_ICOLL_LEVELACK;
 233        icoll_priv.ctrl         = icoll_base + ASM9260_HW_ICOLL_CTRL;
 234        icoll_priv.stat         = icoll_base + ASM9260_HW_ICOLL_STAT_OFFSET;
 235        icoll_priv.intr         = icoll_base + ASM9260_HW_ICOLL_INTERRUPT0;
 236        icoll_priv.clear        = icoll_base + ASM9260_HW_ICOLL_CLEAR0;
 237
 238        writel_relaxed(ASM9260_BM_CTRL_IRQ_ENABLE,
 239                        icoll_priv.ctrl);
 240        /*
 241         * ASM9260 don't provide reset bit. So, we need to set level 0
 242         * manually.
 243         */
 244        for (i = 0; i < 16 * 0x10; i += 0x10)
 245                writel(0, icoll_priv.intr + i);
 246
 247        icoll_add_domain(np, ASM9260_NUM_IRQS);
 248        set_handle_irq(icoll_handle_irq);
 249
 250        return 0;
 251}
 252IRQCHIP_DECLARE(asm9260, "alphascale,asm9260-icoll", asm9260_of_init);
 253