drivers/irqchip/irq-csky-apb-intc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
   3
   4 #include <linux/kernel.h>
   5 #include <linux/init.h>
   6 #include <linux/of.h>
   7 #include <linux/of_address.h>
   8 #include <linux/module.h>
   9 #include <linux/irqdomain.h>
  10 #include <linux/irqchip.h>
  11 #include <linux/irq.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <asm/irq.h>
  15
  16 #define INTC_IRQS               64
  17
  18 #define CK_INTC_ICR             0x00
  19 #define CK_INTC_PEN31_00        0x14
  20 #define CK_INTC_PEN63_32        0x2c
  21 #define CK_INTC_NEN31_00        0x10
  22 #define CK_INTC_NEN63_32        0x28
  23 #define CK_INTC_SOURCE          0x40
  24 #define CK_INTC_DUAL_BASE       0x100
  25
  26 #define GX_INTC_PEN31_00        0x00
  27 #define GX_INTC_PEN63_32        0x04
  28 #define GX_INTC_NEN31_00        0x40
  29 #define GX_INTC_NEN63_32        0x44
  30 #define GX_INTC_NMASK31_00      0x50
  31 #define GX_INTC_NMASK63_32      0x54
  32 #define GX_INTC_SOURCE          0x60
  33
  34 static void __iomem *reg_base;
  35 static struct irq_domain *root_domain;
  36
  37 static int nr_irq = INTC_IRQS;
  38
  39 /*
  40  * When controller support pulse signal, the PEN_reg will hold on signal
  41  * without software trigger.
  42  *
  43  * So, to support pulse signal we need to clear IFR_reg and the address of
  44  * IFR_offset is NEN_offset - 8.
  45  */
  46 static void irq_ck_mask_set_bit(struct irq_data *d)
  47 {
  48         struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
  49         struct irq_chip_type *ct = irq_data_get_chip_type(d);
  50         unsigned long ifr = ct->regs.mask - 8;
  51         u32 mask = d->mask;
  52
  53         irq_gc_lock(gc);
  54         *ct->mask_cache |= mask;
  55         irq_reg_writel(gc, *ct->mask_cache, ct->regs.mask);
  56         irq_reg_writel(gc, irq_reg_readl(gc, ifr) & ~mask, ifr);
  57         irq_gc_unlock(gc);
  58 }
  59
  60 static void __init ck_set_gc(struct device_node *node, void __iomem *reg_base,
  61                              u32 mask_reg, u32 irq_base)
  62 {
  63         struct irq_chip_generic *gc;
  64
  65         gc = irq_get_domain_generic_chip(root_domain, irq_base);
  66         gc->reg_base = reg_base;
  67         gc->chip_types[0].regs.mask = mask_reg;
  68         gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
  69         gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
  70
  71         if (of_find_property(node, "csky,support-pulse-signal", NULL))
  72                 gc->chip_types[0].chip.irq_unmask = irq_ck_mask_set_bit;
  73 }
  74
  75 static inline u32 build_channel_val(u32 idx, u32 magic)
  76 {
  77         u32 res;
  78
  79         /*
  80          * Set the same index for each channel
  81          */
  82         res = idx | (idx << 8) | (idx << 16) | (idx << 24);
  83
  84         /*
  85          * Set the channel magic number in descending order.
  86          * The magic is 0x00010203 for ck-intc
  87          * The magic is 0x03020100 for gx6605s-intc
  88          */
  89         return res | magic;
  90 }
  91
  92 static inline void setup_irq_channel(u32 magic, void __iomem *reg_addr)
  93 {
  94         u32 i;
  95
  96         /* Setup 64 channel slots */
  97         for (i = 0; i < INTC_IRQS; i += 4)
  98                 writel(build_channel_val(i, magic), reg_addr + i);
  99 }
 100
 101 static int __init
 102 ck_intc_init_comm(struct device_node *node, struct device_node *parent)
 103 {
 104         int ret;
 105
 106         if (parent) {
 107                 pr_err("C-SKY Intc not a root irq controller\n");
 108                 return -EINVAL;
 109         }
 110
 111         reg_base = of_iomap(node, 0);
 112         if (!reg_base) {
 113                 pr_err("C-SKY Intc unable to map: %p.\n", node);
 114                 return -EINVAL;
 115         }
 116
 117         root_domain = irq_domain_add_linear(node, nr_irq,
 118                                             &irq_generic_chip_ops, NULL);
 119         if (!root_domain) {
 120                 pr_err("C-SKY Intc irq_domain_add failed.\n");
 121                 return -ENOMEM;
 122         }
 123
 124         ret = irq_alloc_domain_generic_chips(root_domain, 32, 1,
 125                         "csky_intc", handle_level_irq,
 126                         IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN, 0, 0);
 127         if (ret) {
 128                 pr_err("C-SKY Intc irq_alloc_gc failed.\n");
 129                 return -ENOMEM;
 130         }
 131
 132         return 0;
 133 }
 134
 135 static inline bool handle_irq_perbit(struct pt_regs *regs, u32 hwirq,
 136                                      u32 irq_base)
 137 {
 138         if (hwirq == 0)
 139                 return 0;
 140
 141         handle_domain_irq(root_domain, irq_base + __fls(hwirq), regs);
 142
 143         return 1;
 144 }
 145
 146 /* gx6605s 64 irqs interrupt controller */
 147 static void gx_irq_handler(struct pt_regs *regs)
 148 {
 149         bool ret;
 150
 151 retry:
 152         ret = handle_irq_perbit(regs,
 153                         readl(reg_base + GX_INTC_PEN63_32), 32);
 154         if (ret)
 155                 goto retry;
 156
 157         ret = handle_irq_perbit(regs,
 158                         readl(reg_base + GX_INTC_PEN31_00), 0);
 159         if (ret)
 160                 goto retry;
 161 }
 162
 163 static int __init
 164 gx_intc_init(struct device_node *node, struct device_node *parent)
 165 {
 166         int ret;
 167
 168         ret = ck_intc_init_comm(node, parent);
 169         if (ret)
 170                 return ret;
 171
 172         /*
 173          * Initial enable reg to disable all interrupts
 174          */
 175         writel(0x0, reg_base + GX_INTC_NEN31_00);
 176         writel(0x0, reg_base + GX_INTC_NEN63_32);
 177
 178         /*
 179          * Initial mask reg with all unmasked, because we only use enalbe reg
 180          */
 181         writel(0x0, reg_base + GX_INTC_NMASK31_00);
 182         writel(0x0, reg_base + GX_INTC_NMASK63_32);
 183
 184         setup_irq_channel(0x03020100, reg_base + GX_INTC_SOURCE);
 185
 186         ck_set_gc(node, reg_base, GX_INTC_NEN31_00, 0);
 187         ck_set_gc(node, reg_base, GX_INTC_NEN63_32, 32);
 188
 189         set_handle_irq(gx_irq_handler);
 190
 191         return 0;
 192 }
 193 IRQCHIP_DECLARE(csky_gx6605s_intc, "csky,gx6605s-intc", gx_intc_init);
 194
 195 /*
 196  * C-SKY simple 64 irqs interrupt controller, dual-together could support 128
 197  * irqs.
 198  */
 199 static void ck_irq_handler(struct pt_regs *regs)
 200 {
 201         bool ret;
 202         void __iomem *reg_pen_lo = reg_base + CK_INTC_PEN31_00;
 203         void __iomem *reg_pen_hi = reg_base + CK_INTC_PEN63_32;
 204
 205 retry:
 206         /* handle 0 - 63 irqs */
 207         ret = handle_irq_perbit(regs, readl(reg_pen_hi), 32);
 208         if (ret)
 209                 goto retry;
 210
 211         ret = handle_irq_perbit(regs, readl(reg_pen_lo), 0);
 212         if (ret)
 213                 goto retry;
 214
 215         if (nr_irq == INTC_IRQS)
 216                 return;
 217
 218         /* handle 64 - 127 irqs */
 219         ret = handle_irq_perbit(regs,
 220                         readl(reg_pen_hi + CK_INTC_DUAL_BASE), 96);
 221         if (ret)
 222                 goto retry;
 223
 224         ret = handle_irq_perbit(regs,
 225                         readl(reg_pen_lo + CK_INTC_DUAL_BASE), 64);
 226         if (ret)
 227                 goto retry;
 228 }
 229
 230 static int __init
 231 ck_intc_init(struct device_node *node, struct device_node *parent)
 232 {
 233         int ret;
 234
 235         ret = ck_intc_init_comm(node, parent);
 236         if (ret)
 237                 return ret;
 238
 239         /* Initial enable reg to disable all interrupts */
 240         writel(0, reg_base + CK_INTC_NEN31_00);
 241         writel(0, reg_base + CK_INTC_NEN63_32);
 242
 243         /* Enable irq intc */
 244         writel(BIT(31), reg_base + CK_INTC_ICR);
 245
 246         ck_set_gc(node, reg_base, CK_INTC_NEN31_00, 0);
 247         ck_set_gc(node, reg_base, CK_INTC_NEN63_32, 32);
 248
 249         setup_irq_channel(0x00010203, reg_base + CK_INTC_SOURCE);
 250
 251         set_handle_irq(ck_irq_handler);
 252
 253         return 0;
 254 }
 255 IRQCHIP_DECLARE(ck_intc, "csky,apb-intc", ck_intc_init);
 256
 257 static int __init
 258 ck_dual_intc_init(struct device_node *node, struct device_node *parent)
 259 {
 260         int ret;
 261
 262         /* dual-apb-intc up to 128 irq sources*/
 263         nr_irq = INTC_IRQS * 2;
 264
 265         ret = ck_intc_init(node, parent);
 266         if (ret)
 267                 return ret;
 268
 269         /* Initial enable reg to disable all interrupts */
 270         writel(0, reg_base + CK_INTC_NEN31_00 + CK_INTC_DUAL_BASE);
 271         writel(0, reg_base + CK_INTC_NEN63_32 + CK_INTC_DUAL_BASE);
 272
 273         ck_set_gc(node, reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN31_00, 64);
 274         ck_set_gc(node, reg_base + CK_INTC_DUAL_BASE, CK_INTC_NEN63_32, 96);
 275
 276         setup_irq_channel(0x00010203,
 277                           reg_base + CK_INTC_SOURCE + CK_INTC_DUAL_BASE);
 278
 279         return 0;
 280 }
 281 IRQCHIP_DECLARE(ck_dual_intc, "csky,dual-apb-intc", ck_dual_intc_init);