target/linux/ar71xx/files/arch/mips/ar71xx/irq.c

   1 /*
   2  *  Atheros AR71xx SoC specific interrupt handling
   3  *
   4  *  Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
   5  *  Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
   6  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   7  *
   8  *  Parts of this file are based on Atheros 2.6.15 BSP
   9  *  Parts of this file are based on Atheros 2.6.31 BSP
  10  *
  11  *  This program is free software; you can redistribute it and/or modify it
  12  *  under the terms of the GNU General Public License version 2 as published
  13  *  by the Free Software Foundation.
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/irq.h>
  20
  21 #include <asm/irq_cpu.h>
  22 #include <asm/mipsregs.h>
  23
  24 #include <asm/mach-ar71xx/ar71xx.h>
  25
  26 static int ip2_flush_reg;
  27
  28 static void ar71xx_gpio_irq_dispatch(void)
  29 {
  30         void __iomem *base = ar71xx_gpio_base;
  31         u32 pending;
  32
  33         pending = __raw_readl(base + GPIO_REG_INT_PENDING) &
  34                   __raw_readl(base + GPIO_REG_INT_ENABLE);
  35
  36         if (pending)
  37                 do_IRQ(AR71XX_GPIO_IRQ_BASE + fls(pending) - 1);
  38         else
  39                 spurious_interrupt();
  40 }
  41
  42 static void ar71xx_gpio_irq_unmask(unsigned int irq)
  43 {
  44         void __iomem *base = ar71xx_gpio_base;
  45         u32 t;
  46
  47         irq -= AR71XX_GPIO_IRQ_BASE;
  48
  49         t = __raw_readl(base + GPIO_REG_INT_ENABLE);
  50         __raw_writel(t | (1 << irq), base + GPIO_REG_INT_ENABLE);
  51
  52         /* flush write */
  53         (void) __raw_readl(base + GPIO_REG_INT_ENABLE);
  54 }
  55
  56 static void ar71xx_gpio_irq_mask(unsigned int irq)
  57 {
  58         void __iomem *base = ar71xx_gpio_base;
  59         u32 t;
  60
  61         irq -= AR71XX_GPIO_IRQ_BASE;
  62
  63         t = __raw_readl(base + GPIO_REG_INT_ENABLE);
  64         __raw_writel(t & ~(1 << irq), base + GPIO_REG_INT_ENABLE);
  65
  66         /* flush write */
  67         (void) __raw_readl(base + GPIO_REG_INT_ENABLE);
  68 }
  69
  70 #if 0
  71 static int ar71xx_gpio_irq_set_type(unsigned int irq, unsigned int flow_type)
  72 {
  73         /* TODO: implement */
  74         return 0;
  75 }
  76 #else
  77 #define ar71xx_gpio_irq_set_type        NULL
  78 #endif
  79
  80 static struct irq_chip ar71xx_gpio_irq_chip = {
  81         .name           = "AR71XX GPIO",
  82         .unmask         = ar71xx_gpio_irq_unmask,
  83         .mask           = ar71xx_gpio_irq_mask,
  84         .mask_ack       = ar71xx_gpio_irq_mask,
  85         .set_type       = ar71xx_gpio_irq_set_type,
  86 };
  87
  88 static struct irqaction ar71xx_gpio_irqaction = {
  89         .handler        = no_action,
  90         .name           = "cascade [AR71XX GPIO]",
  91 };
  92
  93 #define GPIO_IRQ_INIT_STATUS (IRQ_LEVEL | IRQ_TYPE_LEVEL_HIGH | IRQ_DISABLED)
  94 #define GPIO_INT_ALL    0xffff
  95
  96 static void __init ar71xx_gpio_irq_init(void)
  97 {
  98         void __iomem *base = ar71xx_gpio_base;
  99         int i;
 100
 101         __raw_writel(0, base + GPIO_REG_INT_ENABLE);
 102         __raw_writel(0, base + GPIO_REG_INT_PENDING);
 103
 104         /* setup type of all GPIO interrupts to level sensitive */
 105         __raw_writel(GPIO_INT_ALL, base + GPIO_REG_INT_TYPE);
 106
 107         /* setup polarity of all GPIO interrupts to active high */
 108         __raw_writel(GPIO_INT_ALL, base + GPIO_REG_INT_POLARITY);
 109
 110         for (i = AR71XX_GPIO_IRQ_BASE;
 111              i < AR71XX_GPIO_IRQ_BASE + AR71XX_GPIO_IRQ_COUNT; i++) {
 112                 irq_desc[i].status = GPIO_IRQ_INIT_STATUS;
 113                 set_irq_chip_and_handler(i, &ar71xx_gpio_irq_chip,
 114                                          handle_level_irq);
 115         }
 116
 117         setup_irq(AR71XX_MISC_IRQ_GPIO, &ar71xx_gpio_irqaction);
 118 }
 119
 120 static void ar71xx_misc_irq_dispatch(void)
 121 {
 122         u32 pending;
 123
 124         pending = ar71xx_reset_rr(AR71XX_RESET_REG_MISC_INT_STATUS)
 125             & ar71xx_reset_rr(AR71XX_RESET_REG_MISC_INT_ENABLE);
 126
 127         if (pending & MISC_INT_UART)
 128                 do_IRQ(AR71XX_MISC_IRQ_UART);
 129
 130         else if (pending & MISC_INT_DMA)
 131                 do_IRQ(AR71XX_MISC_IRQ_DMA);
 132
 133         else if (pending & MISC_INT_PERFC)
 134                 do_IRQ(AR71XX_MISC_IRQ_PERFC);
 135
 136         else if (pending & MISC_INT_TIMER)
 137                 do_IRQ(AR71XX_MISC_IRQ_TIMER);
 138
 139         else if (pending & MISC_INT_OHCI)
 140                 do_IRQ(AR71XX_MISC_IRQ_OHCI);
 141
 142         else if (pending & MISC_INT_ERROR)
 143                 do_IRQ(AR71XX_MISC_IRQ_ERROR);
 144
 145         else if (pending & MISC_INT_GPIO)
 146                 ar71xx_gpio_irq_dispatch();
 147
 148         else if (pending & MISC_INT_WDOG)
 149                 do_IRQ(AR71XX_MISC_IRQ_WDOG);
 150
 151         else if (pending & MISC_INT_TIMER2)
 152                 do_IRQ(AR71XX_MISC_IRQ_TIMER2);
 153
 154         else if (pending & MISC_INT_TIMER3)
 155                 do_IRQ(AR71XX_MISC_IRQ_TIMER3);
 156
 157         else if (pending & MISC_INT_TIMER4)
 158                 do_IRQ(AR71XX_MISC_IRQ_TIMER4);
 159
 160         else if (pending & MISC_INT_DDR_PERF)
 161                 do_IRQ(AR71XX_MISC_IRQ_DDR_PERF);
 162
 163         else if (pending & MISC_INT_ENET_LINK)
 164                 do_IRQ(AR71XX_MISC_IRQ_ENET_LINK);
 165
 166         else
 167                 spurious_interrupt();
 168 }
 169
 170 static void ar71xx_misc_irq_unmask(unsigned int irq)
 171 {
 172         void __iomem *base = ar71xx_reset_base;
 173         u32 t;
 174
 175         irq -= AR71XX_MISC_IRQ_BASE;
 176
 177         t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 178         __raw_writel(t | (1 << irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 179
 180         /* flush write */
 181         (void) __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 182 }
 183
 184 static void ar71xx_misc_irq_mask(unsigned int irq)
 185 {
 186         void __iomem *base = ar71xx_reset_base;
 187         u32 t;
 188
 189         irq -= AR71XX_MISC_IRQ_BASE;
 190
 191         t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 192         __raw_writel(t & ~(1 << irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 193
 194         /* flush write */
 195         (void) __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 196 }
 197
 198 static void ar724x_misc_irq_ack(unsigned int irq)
 199 {
 200         void __iomem *base = ar71xx_reset_base;
 201         u32 t;
 202
 203         irq -= AR71XX_MISC_IRQ_BASE;
 204
 205         t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
 206         __raw_writel(t & ~(1 << irq), base + AR71XX_RESET_REG_MISC_INT_STATUS);
 207
 208         /* flush write */
 209         (void) __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
 210 }
 211
 212 static struct irq_chip ar71xx_misc_irq_chip = {
 213         .name           = "AR71XX MISC",
 214         .unmask         = ar71xx_misc_irq_unmask,
 215         .mask           = ar71xx_misc_irq_mask,
 216 };
 217
 218 static struct irqaction ar71xx_misc_irqaction = {
 219         .handler        = no_action,
 220         .name           = "cascade [AR71XX MISC]",
 221 };
 222
 223 static void __init ar71xx_misc_irq_init(void)
 224 {
 225         void __iomem *base = ar71xx_reset_base;
 226         int i;
 227
 228         __raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_ENABLE);
 229         __raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_STATUS);
 230
 231         switch (ar71xx_soc) {
 232         case AR71XX_SOC_AR7240:
 233         case AR71XX_SOC_AR7241:
 234         case AR71XX_SOC_AR7242:
 235         case AR71XX_SOC_AR9341:
 236         case AR71XX_SOC_AR9342:
 237         case AR71XX_SOC_AR9344:
 238                 ar71xx_misc_irq_chip.ack = ar724x_misc_irq_ack;
 239                 break;
 240         default:
 241                 ar71xx_misc_irq_chip.mask_ack = ar71xx_misc_irq_mask;
 242                 break;
 243         }
 244
 245         for (i = AR71XX_MISC_IRQ_BASE;
 246              i < AR71XX_MISC_IRQ_BASE + AR71XX_MISC_IRQ_COUNT; i++) {
 247                 irq_desc[i].status = IRQ_DISABLED;
 248                 set_irq_chip_and_handler(i, &ar71xx_misc_irq_chip,
 249                                          handle_level_irq);
 250         }
 251
 252         setup_irq(AR71XX_CPU_IRQ_MISC, &ar71xx_misc_irqaction);
 253 }
 254
 255 asmlinkage void plat_irq_dispatch(void)
 256 {
 257         unsigned long pending;
 258
 259         pending = read_c0_status() & read_c0_cause() & ST0_IM;
 260
 261         if (pending & STATUSF_IP7)
 262                 do_IRQ(AR71XX_CPU_IRQ_TIMER);
 263
 264         else if (pending & STATUSF_IP2) {
 265                 /*
 266                  * This IRQ is meant for a PCI device. Drivers for PCI devices
 267                  * typically allocate coherent DMA memory for the descriptor
 268                  * ring, however the DMA controller may still have some
 269                  * unsynchronized data in the FIFO.
 270                  * Issue a flush here to ensure that the driver sees the update.
 271                  */
 272                 ar71xx_ddr_flush(ip2_flush_reg);
 273                 do_IRQ(AR71XX_CPU_IRQ_IP2);
 274         }
 275
 276         else if (pending & STATUSF_IP4)
 277                 do_IRQ(AR71XX_CPU_IRQ_GE0);
 278
 279         else if (pending & STATUSF_IP5)
 280                 do_IRQ(AR71XX_CPU_IRQ_GE1);
 281
 282         else if (pending & STATUSF_IP3)
 283                 do_IRQ(AR71XX_CPU_IRQ_USB);
 284
 285         else if (pending & STATUSF_IP6)
 286                 ar71xx_misc_irq_dispatch();
 287
 288         else
 289                 spurious_interrupt();
 290 }
 291
 292 void __init arch_init_irq(void)
 293 {
 294         switch (ar71xx_soc) {
 295         case AR71XX_SOC_AR7240:
 296         case AR71XX_SOC_AR7241:
 297         case AR71XX_SOC_AR7242:
 298                 ip2_flush_reg = AR724X_DDR_REG_FLUSH_PCIE;
 299                 break;
 300         case AR71XX_SOC_AR9130:
 301         case AR71XX_SOC_AR9132:
 302                 ip2_flush_reg = AR91XX_DDR_REG_FLUSH_WMAC;
 303                 break;
 304         case AR71XX_SOC_AR9341:
 305         case AR71XX_SOC_AR9342:
 306         case AR71XX_SOC_AR9344:
 307                 ip2_flush_reg = AR934X_DDR_REG_FLUSH_PCIE;
 308                 break;
 309
 310         default:
 311                 ip2_flush_reg = AR71XX_DDR_REG_FLUSH_PCI;
 312                 break;
 313         }
 314
 315         mips_cpu_irq_init();
 316
 317         ar71xx_misc_irq_init();
 318
 319         cp0_perfcount_irq = AR71XX_MISC_IRQ_PERFC;
 320
 321         ar71xx_gpio_irq_init();
 322 }