1 /* 2 * arch/arm/mach-dove/irq.c 3 * 4 * Dove IRQ handling. 5 * 6 * This file is licensed under the terms of the GNU General Public 7 * License version 2. This program is licensed "as is" without any 8 * warranty of any kind, whether express or implied. 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/init.h> 13 #include <linux/irq.h> 14 #include <linux/gpio.h> 15 #include <linux/io.h> 16 #include <asm/mach/arch.h> 17 #include <plat/irq.h> 18 #include <asm/mach/irq.h> 19 #include <mach/pm.h> 20 #include <mach/bridge-regs.h> 21 #include <plat/orion-gpio.h> 22 #include "common.h" 23 24 static void pmu_irq_mask(struct irq_data *d) 25 { 26 int pin = irq_to_pmu(d->irq); 27 u32 u; 28 29 u = readl(PMU_INTERRUPT_MASK); 30 u &= ~(1 << (pin & 31)); 31 writel(u, PMU_INTERRUPT_MASK); 32 } 33 34 static void pmu_irq_unmask(struct irq_data *d) 35 { 36 int pin = irq_to_pmu(d->irq); 37 u32 u; 38 39 u = readl(PMU_INTERRUPT_MASK); 40 u |= 1 << (pin & 31); 41 writel(u, PMU_INTERRUPT_MASK); 42 } 43 44 static void pmu_irq_ack(struct irq_data *d) 45 { 46 int pin = irq_to_pmu(d->irq); 47 u32 u; 48 49 /* 50 * The PMU mask register is not RW0C: it is RW. This means that 51 * the bits take whatever value is written to them; if you write 52 * a '1', you will set the interrupt. 53 * 54 * Unfortunately this means there is NO race free way to clear 55 * these interrupts. 56 * 57 * So, let's structure the code so that the window is as small as 58 * possible. 59 */ 60 u = ~(1 << (pin & 31)); 61 u &= readl_relaxed(PMU_INTERRUPT_CAUSE); 62 writel_relaxed(u, PMU_INTERRUPT_CAUSE); 63 } 64 65 static struct irq_chip pmu_irq_chip = { 66 .name = "pmu_irq", 67 .irq_mask = pmu_irq_mask, 68 .irq_unmask = pmu_irq_unmask, 69 .irq_ack = pmu_irq_ack, 70 }; 71 72 static void pmu_irq_handler(unsigned int irq, struct irq_desc *desc) 73 { 74 unsigned long cause = readl(PMU_INTERRUPT_CAUSE); 75 76 cause &= readl(PMU_INTERRUPT_MASK); 77 if (cause == 0) { 78 do_bad_IRQ(irq, desc); 79 return; 80 } 81 82 for (irq = 0; irq < NR_PMU_IRQS; irq++) { 83 if (!(cause & (1 << irq))) 84 continue; 85 irq = pmu_to_irq(irq); 86 generic_handle_irq(irq); 87 } 88 } 89 90 static int __initdata gpio0_irqs[4] = { 91 IRQ_DOVE_GPIO_0_7, 92 IRQ_DOVE_GPIO_8_15, 93 IRQ_DOVE_GPIO_16_23, 94 IRQ_DOVE_GPIO_24_31, 95 }; 96 97 static int __initdata gpio1_irqs[4] = { 98 IRQ_DOVE_HIGH_GPIO, 99 0, 100 0, 101 0, 102 }; 103 104 static int __initdata gpio2_irqs[4] = { 105 0, 106 0, 107 0, 108 0, 109 }; 110 111 #ifdef CONFIG_MULTI_IRQ_HANDLER 112 /* 113 * Compiling with both non-DT and DT support enabled, will 114 * break asm irq handler used by non-DT boards. Therefore, 115 * we provide a C-style irq handler even for non-DT boards, 116 * if MULTI_IRQ_HANDLER is set. 117 */ 118 119 static void __iomem *dove_irq_base = IRQ_VIRT_BASE; 120 121 static asmlinkage void 122 __exception_irq_entry dove_legacy_handle_irq(struct pt_regs *regs) 123 { 124 u32 stat; 125 126 stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_LOW_OFF); 127 stat &= readl_relaxed(dove_irq_base + IRQ_MASK_LOW_OFF); 128 if (stat) { 129 unsigned int hwirq = __fls(stat); 130 handle_IRQ(hwirq, regs); 131 return; 132 } 133 stat = readl_relaxed(dove_irq_base + IRQ_CAUSE_HIGH_OFF); 134 stat &= readl_relaxed(dove_irq_base + IRQ_MASK_HIGH_OFF); 135 if (stat) { 136 unsigned int hwirq = 32 + __fls(stat); 137 handle_IRQ(hwirq, regs); 138 return; 139 } 140 } 141 #endif 142 143 void __init dove_init_irq(void) 144 { 145 int i; 146 147 orion_irq_init(0, IRQ_VIRT_BASE + IRQ_MASK_LOW_OFF); 148 orion_irq_init(32, IRQ_VIRT_BASE + IRQ_MASK_HIGH_OFF); 149 150 #ifdef CONFIG_MULTI_IRQ_HANDLER 151 set_handle_irq(dove_legacy_handle_irq); 152 #endif 153 154 /* 155 * Initialize gpiolib for GPIOs 0-71. 156 */ 157 orion_gpio_init(NULL, 0, 32, DOVE_GPIO_LO_VIRT_BASE, 0, 158 IRQ_DOVE_GPIO_START, gpio0_irqs); 159 160 orion_gpio_init(NULL, 32, 32, DOVE_GPIO_HI_VIRT_BASE, 0, 161 IRQ_DOVE_GPIO_START + 32, gpio1_irqs); 162 163 orion_gpio_init(NULL, 64, 8, DOVE_GPIO2_VIRT_BASE, 0, 164 IRQ_DOVE_GPIO_START + 64, gpio2_irqs); 165 166 /* 167 * Mask and clear PMU interrupts 168 */ 169 writel(0, PMU_INTERRUPT_MASK); 170 writel(0, PMU_INTERRUPT_CAUSE); 171 172 for (i = IRQ_DOVE_PMU_START; i < NR_IRQS; i++) { 173 irq_set_chip_and_handler(i, &pmu_irq_chip, handle_level_irq); 174 irq_set_status_flags(i, IRQ_LEVEL); 175 set_irq_flags(i, IRQF_VALID); 176 } 177 irq_set_chained_handler(IRQ_DOVE_PMU, pmu_irq_handler); 178 } 179