1 /* 2 * Copyright (C) 2016 Marvell 3 * 4 * Yehuda Yitschak <yehuday@marvell.com> 5 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com> 6 * 7 * This file is licensed under the terms of the GNU General Public 8 * License version 2. This program is licensed "as is" without any 9 * warranty of any kind, whether express or implied. 10 */ 11 12 #include <linux/interrupt.h> 13 #include <linux/io.h> 14 #include <linux/irq.h> 15 #include <linux/irqchip.h> 16 #include <linux/irqchip/chained_irq.h> 17 #include <linux/irqdomain.h> 18 #include <linux/module.h> 19 #include <linux/of_irq.h> 20 #include <linux/platform_device.h> 21 #include <linux/seq_file.h> 22 23 #define PIC_CAUSE 0x0 24 #define PIC_MASK 0x4 25 26 #define PIC_MAX_IRQS 32 27 #define PIC_MAX_IRQ_MASK ((1UL << PIC_MAX_IRQS) - 1) 28 29 struct mvebu_pic { 30 void __iomem *base; 31 u32 parent_irq; 32 struct irq_domain *domain; 33 struct platform_device *pdev; 34 }; 35 36 static void mvebu_pic_reset(struct mvebu_pic *pic) 37 { 38 /* ACK and mask all interrupts */ 39 writel(0, pic->base + PIC_MASK); 40 writel(PIC_MAX_IRQ_MASK, pic->base + PIC_CAUSE); 41 } 42 43 static void mvebu_pic_eoi_irq(struct irq_data *d) 44 { 45 struct mvebu_pic *pic = irq_data_get_irq_chip_data(d); 46 47 writel(1 << d->hwirq, pic->base + PIC_CAUSE); 48 } 49 50 static void mvebu_pic_mask_irq(struct irq_data *d) 51 { 52 struct mvebu_pic *pic = irq_data_get_irq_chip_data(d); 53 u32 reg; 54 55 reg = readl(pic->base + PIC_MASK); 56 reg |= (1 << d->hwirq); 57 writel(reg, pic->base + PIC_MASK); 58 } 59 60 static void mvebu_pic_unmask_irq(struct irq_data *d) 61 { 62 struct mvebu_pic *pic = irq_data_get_irq_chip_data(d); 63 u32 reg; 64 65 reg = readl(pic->base + PIC_MASK); 66 reg &= ~(1 << d->hwirq); 67 writel(reg, pic->base + PIC_MASK); 68 } 69 70 static void mvebu_pic_print_chip(struct irq_data *d, struct seq_file *p) 71 { 72 struct mvebu_pic *pic = irq_data_get_irq_chip_data(d); 73 74 seq_printf(p, dev_name(&pic->pdev->dev)); 75 } 76 77 static const struct irq_chip mvebu_pic_chip = { 78 .irq_mask = mvebu_pic_mask_irq, 79 .irq_unmask = mvebu_pic_unmask_irq, 80 .irq_eoi = mvebu_pic_eoi_irq, 81 .irq_print_chip = mvebu_pic_print_chip, 82 }; 83 84 static int mvebu_pic_irq_map(struct irq_domain *domain, unsigned int virq, 85 irq_hw_number_t hwirq) 86 { 87 struct mvebu_pic *pic = domain->host_data; 88 89 irq_set_percpu_devid(virq); 90 irq_set_chip_data(virq, pic); 91 irq_set_chip_and_handler(virq, &mvebu_pic_chip, handle_percpu_devid_irq); 92 irq_set_status_flags(virq, IRQ_LEVEL); 93 irq_set_probe(virq); 94 95 return 0; 96 } 97 98 static const struct irq_domain_ops mvebu_pic_domain_ops = { 99 .map = mvebu_pic_irq_map, 100 .xlate = irq_domain_xlate_onecell, 101 }; 102 103 static void mvebu_pic_handle_cascade_irq(struct irq_desc *desc) 104 { 105 struct mvebu_pic *pic = irq_desc_get_handler_data(desc); 106 struct irq_chip *chip = irq_desc_get_chip(desc); 107 unsigned long irqmap, irqn; 108 109 irqmap = readl_relaxed(pic->base + PIC_CAUSE); 110 chained_irq_enter(chip, desc); 111 112 for_each_set_bit(irqn, &irqmap, BITS_PER_LONG) 113 generic_handle_domain_irq(pic->domain, irqn); 114 115 chained_irq_exit(chip, desc); 116 } 117 118 static void mvebu_pic_enable_percpu_irq(void *data) 119 { 120 struct mvebu_pic *pic = data; 121 122 mvebu_pic_reset(pic); 123 enable_percpu_irq(pic->parent_irq, IRQ_TYPE_NONE); 124 } 125 126 static void mvebu_pic_disable_percpu_irq(void *data) 127 { 128 struct mvebu_pic *pic = data; 129 130 disable_percpu_irq(pic->parent_irq); 131 } 132 133 static int mvebu_pic_probe(struct platform_device *pdev) 134 { 135 struct device_node *node = pdev->dev.of_node; 136 struct mvebu_pic *pic; 137 138 pic = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_pic), GFP_KERNEL); 139 if (!pic) 140 return -ENOMEM; 141 142 pic->pdev = pdev; 143 pic->base = devm_platform_ioremap_resource(pdev, 0); 144 if (IS_ERR(pic->base)) 145 return PTR_ERR(pic->base); 146 147 pic->parent_irq = irq_of_parse_and_map(node, 0); 148 if (pic->parent_irq <= 0) { 149 dev_err(&pdev->dev, "Failed to parse parent interrupt\n"); 150 return -EINVAL; 151 } 152 153 pic->domain = irq_domain_add_linear(node, PIC_MAX_IRQS, 154 &mvebu_pic_domain_ops, pic); 155 if (!pic->domain) { 156 dev_err(&pdev->dev, "Failed to allocate irq domain\n"); 157 return -ENOMEM; 158 } 159 160 irq_set_chained_handler(pic->parent_irq, mvebu_pic_handle_cascade_irq); 161 irq_set_handler_data(pic->parent_irq, pic); 162 163 on_each_cpu(mvebu_pic_enable_percpu_irq, pic, 1); 164 165 platform_set_drvdata(pdev, pic); 166 167 return 0; 168 } 169 170 static void mvebu_pic_remove(struct platform_device *pdev) 171 { 172 struct mvebu_pic *pic = platform_get_drvdata(pdev); 173 174 on_each_cpu(mvebu_pic_disable_percpu_irq, pic, 1); 175 irq_domain_remove(pic->domain); 176 } 177 178 static const struct of_device_id mvebu_pic_of_match[] = { 179 { .compatible = "marvell,armada-8k-pic", }, 180 {}, 181 }; 182 MODULE_DEVICE_TABLE(of, mvebu_pic_of_match); 183 184 static struct platform_driver mvebu_pic_driver = { 185 .probe = mvebu_pic_probe, 186 .remove_new = mvebu_pic_remove, 187 .driver = { 188 .name = "mvebu-pic", 189 .of_match_table = mvebu_pic_of_match, 190 }, 191 }; 192 module_platform_driver(mvebu_pic_driver); 193 194 MODULE_AUTHOR("Yehuda Yitschak <yehuday@marvell.com>"); 195 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>"); 196 MODULE_LICENSE("GPL v2"); 197 MODULE_ALIAS("platform:mvebu_pic"); 198 199