drivers/irqchip/irq-imx-gpcv2.c

   1 /*
   2  * Copyright (C) 2015 Freescale Semiconductor, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/of_address.h>
  10 #include <linux/of_irq.h>
  11 #include <linux/slab.h>
  12 #include <linux/irqchip.h>
  13 #include <linux/syscore_ops.h>
  14
  15 #define IMR_NUM                 4
  16 #define GPC_MAX_IRQS            (IMR_NUM * 32)
  17
  18 #define GPC_IMR1_CORE0          0x30
  19 #define GPC_IMR1_CORE1          0x40
  20
  21 struct gpcv2_irqchip_data {
  22         struct raw_spinlock     rlock;
  23         void __iomem            *gpc_base;
  24         u32                     wakeup_sources[IMR_NUM];
  25         u32                     saved_irq_mask[IMR_NUM];
  26         u32                     cpu2wakeup;
  27 };
  28
  29 static struct gpcv2_irqchip_data *imx_gpcv2_instance;
  30
  31 static int gpcv2_wakeup_source_save(void)
  32 {
  33         struct gpcv2_irqchip_data *cd;
  34         void __iomem *reg;
  35         int i;
  36
  37         cd = imx_gpcv2_instance;
  38         if (!cd)
  39                 return 0;
  40
  41         for (i = 0; i < IMR_NUM; i++) {
  42                 reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
  43                 cd->saved_irq_mask[i] = readl_relaxed(reg);
  44                 writel_relaxed(cd->wakeup_sources[i], reg);
  45         }
  46
  47         return 0;
  48 }
  49
  50 static void gpcv2_wakeup_source_restore(void)
  51 {
  52         struct gpcv2_irqchip_data *cd;
  53         void __iomem *reg;
  54         int i;
  55
  56         cd = imx_gpcv2_instance;
  57         if (!cd)
  58                 return;
  59
  60         for (i = 0; i < IMR_NUM; i++) {
  61                 reg = cd->gpc_base + cd->cpu2wakeup + i * 4;
  62                 writel_relaxed(cd->saved_irq_mask[i], reg);
  63         }
  64 }
  65
  66 static struct syscore_ops imx_gpcv2_syscore_ops = {
  67         .suspend        = gpcv2_wakeup_source_save,
  68         .resume         = gpcv2_wakeup_source_restore,
  69 };
  70
  71 static int imx_gpcv2_irq_set_wake(struct irq_data *d, unsigned int on)
  72 {
  73         struct gpcv2_irqchip_data *cd = d->chip_data;
  74         unsigned int idx = d->hwirq / 32;
  75         unsigned long flags;
  76         void __iomem *reg;
  77         u32 mask, val;
  78
  79         raw_spin_lock_irqsave(&cd->rlock, flags);
  80         reg = cd->gpc_base + cd->cpu2wakeup + idx * 4;
  81         mask = 1 << d->hwirq % 32;
  82         val = cd->wakeup_sources[idx];
  83
  84         cd->wakeup_sources[idx] = on ? (val & ~mask) : (val | mask);
  85         raw_spin_unlock_irqrestore(&cd->rlock, flags);
  86
  87         /*
  88          * Do *not* call into the parent, as the GIC doesn't have any
  89          * wake-up facility...
  90          */
  91
  92         return 0;
  93 }
  94
  95 static void imx_gpcv2_irq_unmask(struct irq_data *d)
  96 {
  97         struct gpcv2_irqchip_data *cd = d->chip_data;
  98         void __iomem *reg;
  99         u32 val;
 100
 101         raw_spin_lock(&cd->rlock);
 102         reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
 103         val = readl_relaxed(reg);
 104         val &= ~(1 << d->hwirq % 32);
 105         writel_relaxed(val, reg);
 106         raw_spin_unlock(&cd->rlock);
 107
 108         irq_chip_unmask_parent(d);
 109 }
 110
 111 static void imx_gpcv2_irq_mask(struct irq_data *d)
 112 {
 113         struct gpcv2_irqchip_data *cd = d->chip_data;
 114         void __iomem *reg;
 115         u32 val;
 116
 117         raw_spin_lock(&cd->rlock);
 118         reg = cd->gpc_base + cd->cpu2wakeup + d->hwirq / 32 * 4;
 119         val = readl_relaxed(reg);
 120         val |= 1 << (d->hwirq % 32);
 121         writel_relaxed(val, reg);
 122         raw_spin_unlock(&cd->rlock);
 123
 124         irq_chip_mask_parent(d);
 125 }
 126
 127 static struct irq_chip gpcv2_irqchip_data_chip = {
 128         .name                   = "GPCv2",
 129         .irq_eoi                = irq_chip_eoi_parent,
 130         .irq_mask               = imx_gpcv2_irq_mask,
 131         .irq_unmask             = imx_gpcv2_irq_unmask,
 132         .irq_set_wake           = imx_gpcv2_irq_set_wake,
 133         .irq_retrigger          = irq_chip_retrigger_hierarchy,
 134 #ifdef CONFIG_SMP
 135         .irq_set_affinity       = irq_chip_set_affinity_parent,
 136 #endif
 137 };
 138
 139 static int imx_gpcv2_domain_translate(struct irq_domain *d,
 140                                       struct irq_fwspec *fwspec,
 141                                       unsigned long *hwirq,
 142                                       unsigned int *type)
 143 {
 144         if (is_of_node(fwspec->fwnode)) {
 145                 if (fwspec->param_count != 3)
 146                         return -EINVAL;
 147
 148                 /* No PPI should point to this domain */
 149                 if (fwspec->param[0] != 0)
 150                         return -EINVAL;
 151
 152                 *hwirq = fwspec->param[1];
 153                 *type = fwspec->param[2];
 154                 return 0;
 155         }
 156
 157         return -EINVAL;
 158 }
 159
 160 static int imx_gpcv2_domain_alloc(struct irq_domain *domain,
 161                                   unsigned int irq, unsigned int nr_irqs,
 162                                   void *data)
 163 {
 164         struct irq_fwspec *fwspec = data;
 165         struct irq_fwspec parent_fwspec;
 166         irq_hw_number_t hwirq;
 167         unsigned int type;
 168         int err;
 169         int i;
 170
 171         err = imx_gpcv2_domain_translate(domain, fwspec, &hwirq, &type);
 172         if (err)
 173                 return err;
 174
 175         if (hwirq >= GPC_MAX_IRQS)
 176                 return -EINVAL;
 177
 178         for (i = 0; i < nr_irqs; i++) {
 179                 irq_domain_set_hwirq_and_chip(domain, irq + i, hwirq + i,
 180                                 &gpcv2_irqchip_data_chip, domain->host_data);
 181         }
 182
 183         parent_fwspec = *fwspec;
 184         parent_fwspec.fwnode = domain->parent->fwnode;
 185         return irq_domain_alloc_irqs_parent(domain, irq, nr_irqs,
 186                                             &parent_fwspec);
 187 }
 188
 189 static const struct irq_domain_ops gpcv2_irqchip_data_domain_ops = {
 190         .translate      = imx_gpcv2_domain_translate,
 191         .alloc          = imx_gpcv2_domain_alloc,
 192         .free           = irq_domain_free_irqs_common,
 193 };
 194
 195 static int __init imx_gpcv2_irqchip_init(struct device_node *node,
 196                                struct device_node *parent)
 197 {
 198         struct irq_domain *parent_domain, *domain;
 199         struct gpcv2_irqchip_data *cd;
 200         int i;
 201
 202         if (!parent) {
 203                 pr_err("%pOF: no parent, giving up\n", node);
 204                 return -ENODEV;
 205         }
 206
 207         parent_domain = irq_find_host(parent);
 208         if (!parent_domain) {
 209                 pr_err("%pOF: unable to get parent domain\n", node);
 210                 return -ENXIO;
 211         }
 212
 213         cd = kzalloc(sizeof(struct gpcv2_irqchip_data), GFP_KERNEL);
 214         if (!cd) {
 215                 pr_err("kzalloc failed!\n");
 216                 return -ENOMEM;
 217         }
 218
 219         raw_spin_lock_init(&cd->rlock);
 220
 221         cd->gpc_base = of_iomap(node, 0);
 222         if (!cd->gpc_base) {
 223                 pr_err("fsl-gpcv2: unable to map gpc registers\n");
 224                 kfree(cd);
 225                 return -ENOMEM;
 226         }
 227
 228         domain = irq_domain_add_hierarchy(parent_domain, 0, GPC_MAX_IRQS,
 229                                 node, &gpcv2_irqchip_data_domain_ops, cd);
 230         if (!domain) {
 231                 iounmap(cd->gpc_base);
 232                 kfree(cd);
 233                 return -ENOMEM;
 234         }
 235         irq_set_default_host(domain);
 236
 237         /* Initially mask all interrupts */
 238         for (i = 0; i < IMR_NUM; i++) {
 239                 writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE0 + i * 4);
 240                 writel_relaxed(~0, cd->gpc_base + GPC_IMR1_CORE1 + i * 4);
 241                 cd->wakeup_sources[i] = ~0;
 242         }
 243
 244         /* Let CORE0 as the default CPU to wake up by GPC */
 245         cd->cpu2wakeup = GPC_IMR1_CORE0;
 246
 247         /*
 248          * Due to hardware design failure, need to make sure GPR
 249          * interrupt(#32) is unmasked during RUN mode to avoid entering
 250          * DSM by mistake.
 251          */
 252         writel_relaxed(~0x1, cd->gpc_base + cd->cpu2wakeup);
 253
 254         imx_gpcv2_instance = cd;
 255         register_syscore_ops(&imx_gpcv2_syscore_ops);
 256
 257         /*
 258          * Clear the OF_POPULATED flag set in of_irq_init so that
 259          * later the GPC power domain driver will not be skipped.
 260          */
 261         of_node_clear_flag(node, OF_POPULATED);
 262         return 0;
 263 }
 264
 265 IRQCHIP_DECLARE(imx_gpcv2, "fsl,imx7d-gpc", imx_gpcv2_irqchip_init);