// SPDX-License-Identifier: GPL-2.0-or-later /* * Aspeed AST24XX, AST25XX, and AST26XX SCU Interrupt Controller * Copyright 2019 IBM Corporation * * Eddie James */ #include #include #include #include #include #include #include #include #define ASPEED_SCU_IC_REG 0x018 #define ASPEED_SCU_IC_SHIFT 0 #define ASPEED_SCU_IC_ENABLE GENMASK(6, ASPEED_SCU_IC_SHIFT) #define ASPEED_SCU_IC_NUM_IRQS 7 #define ASPEED_SCU_IC_STATUS_SHIFT 16 #define ASPEED_AST2600_SCU_IC0_REG 0x560 #define ASPEED_AST2600_SCU_IC0_SHIFT 0 #define ASPEED_AST2600_SCU_IC0_ENABLE \ GENMASK(5, ASPEED_AST2600_SCU_IC0_SHIFT) #define ASPEED_AST2600_SCU_IC0_NUM_IRQS 6 #define ASPEED_AST2600_SCU_IC1_REG 0x570 #define ASPEED_AST2600_SCU_IC1_SHIFT 4 #define ASPEED_AST2600_SCU_IC1_ENABLE \ GENMASK(5, ASPEED_AST2600_SCU_IC1_SHIFT) #define ASPEED_AST2600_SCU_IC1_NUM_IRQS 2 struct aspeed_scu_ic { unsigned long irq_enable; unsigned long irq_shift; unsigned int num_irqs; unsigned int reg; struct regmap *scu; struct irq_domain *irq_domain; }; static void aspeed_scu_ic_irq_handler(struct irq_desc *desc) { unsigned int sts; unsigned long bit; unsigned long enabled; unsigned long max; unsigned long status; struct aspeed_scu_ic *scu_ic = irq_desc_get_handler_data(desc); struct irq_chip *chip = irq_desc_get_chip(desc); unsigned int mask = scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT; chained_irq_enter(chip, desc); /* * The SCU IC has just one register to control its operation and read * status. The interrupt enable bits occupy the lower 16 bits of the * register, while the interrupt status bits occupy the upper 16 bits. * The status bit for a given interrupt is always 16 bits shifted from * the enable bit for the same interrupt. * Therefore, perform the IRQ operations in the enable bit space by * shifting the status down to get the mapping and then back up to * clear the bit. */ regmap_read(scu_ic->scu, scu_ic->reg, &sts); enabled = sts & scu_ic->irq_enable; status = (sts >> ASPEED_SCU_IC_STATUS_SHIFT) & enabled; bit = scu_ic->irq_shift; max = scu_ic->num_irqs + bit; for_each_set_bit_from(bit, &status, max) { generic_handle_domain_irq(scu_ic->irq_domain, bit - scu_ic->irq_shift); regmap_write_bits(scu_ic->scu, scu_ic->reg, mask, BIT(bit + ASPEED_SCU_IC_STATUS_SHIFT)); } chained_irq_exit(chip, desc); } static void aspeed_scu_ic_irq_mask(struct irq_data *data) { struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data); unsigned int mask = BIT(data->hwirq + scu_ic->irq_shift) | (scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT); /* * Status bits are cleared by writing 1. In order to prevent the mask * operation from clearing the status bits, they should be under the * mask and written with 0. */ regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, 0); } static void aspeed_scu_ic_irq_unmask(struct irq_data *data) { struct aspeed_scu_ic *scu_ic = irq_data_get_irq_chip_data(data); unsigned int bit = BIT(data->hwirq + scu_ic->irq_shift); unsigned int mask = bit | (scu_ic->irq_enable << ASPEED_SCU_IC_STATUS_SHIFT); /* * Status bits are cleared by writing 1. In order to prevent the unmask * operation from clearing the status bits, they should be under the * mask and written with 0. */ regmap_update_bits(scu_ic->scu, scu_ic->reg, mask, bit); } static int aspeed_scu_ic_irq_set_affinity(struct irq_data *data, const struct cpumask *dest, bool force) { return -EINVAL; } static struct irq_chip aspeed_scu_ic_chip = { .name = "aspeed-scu-ic", .irq_mask = aspeed_scu_ic_irq_mask, .irq_unmask = aspeed_scu_ic_irq_unmask, .irq_set_affinity = aspeed_scu_ic_irq_set_affinity, }; static int aspeed_scu_ic_map(struct irq_domain *domain, unsigned int irq, irq_hw_number_t hwirq) { irq_set_chip_and_handler(irq, &aspeed_scu_ic_chip, handle_level_irq); irq_set_chip_data(irq, domain->host_data); return 0; } static const struct irq_domain_ops aspeed_scu_ic_domain_ops = { .map = aspeed_scu_ic_map, }; static int aspeed_scu_ic_of_init_common(struct aspeed_scu_ic *scu_ic, struct device_node *node) { int irq; int rc = 0; if (!node->parent) { rc = -ENODEV; goto err; } scu_ic->scu = syscon_node_to_regmap(node->parent); if (IS_ERR(scu_ic->scu)) { rc = PTR_ERR(scu_ic->scu); goto err; } irq = irq_of_parse_and_map(node, 0); if (!irq) { rc = -EINVAL; goto err; } scu_ic->irq_domain = irq_domain_add_linear(node, scu_ic->num_irqs, &aspeed_scu_ic_domain_ops, scu_ic); if (!scu_ic->irq_domain) { rc = -ENOMEM; goto err; } irq_set_chained_handler_and_data(irq, aspeed_scu_ic_irq_handler, scu_ic); return 0; err: kfree(scu_ic); return rc; } static int __init aspeed_scu_ic_of_init(struct device_node *node, struct device_node *parent) { struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL); if (!scu_ic) return -ENOMEM; scu_ic->irq_enable = ASPEED_SCU_IC_ENABLE; scu_ic->irq_shift = ASPEED_SCU_IC_SHIFT; scu_ic->num_irqs = ASPEED_SCU_IC_NUM_IRQS; scu_ic->reg = ASPEED_SCU_IC_REG; return aspeed_scu_ic_of_init_common(scu_ic, node); } static int __init aspeed_ast2600_scu_ic0_of_init(struct device_node *node, struct device_node *parent) { struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL); if (!scu_ic) return -ENOMEM; scu_ic->irq_enable = ASPEED_AST2600_SCU_IC0_ENABLE; scu_ic->irq_shift = ASPEED_AST2600_SCU_IC0_SHIFT; scu_ic->num_irqs = ASPEED_AST2600_SCU_IC0_NUM_IRQS; scu_ic->reg = ASPEED_AST2600_SCU_IC0_REG; return aspeed_scu_ic_of_init_common(scu_ic, node); } static int __init aspeed_ast2600_scu_ic1_of_init(struct device_node *node, struct device_node *parent) { struct aspeed_scu_ic *scu_ic = kzalloc(sizeof(*scu_ic), GFP_KERNEL); if (!scu_ic) return -ENOMEM; scu_ic->irq_enable = ASPEED_AST2600_SCU_IC1_ENABLE; scu_ic->irq_shift = ASPEED_AST2600_SCU_IC1_SHIFT; scu_ic->num_irqs = ASPEED_AST2600_SCU_IC1_NUM_IRQS; scu_ic->reg = ASPEED_AST2600_SCU_IC1_REG; return aspeed_scu_ic_of_init_common(scu_ic, node); } IRQCHIP_DECLARE(ast2400_scu_ic, "aspeed,ast2400-scu-ic", aspeed_scu_ic_of_init); IRQCHIP_DECLARE(ast2500_scu_ic, "aspeed,ast2500-scu-ic", aspeed_scu_ic_of_init); IRQCHIP_DECLARE(ast2600_scu_ic0, "aspeed,ast2600-scu-ic0", aspeed_ast2600_scu_ic0_of_init); IRQCHIP_DECLARE(ast2600_scu_ic1, "aspeed,ast2600-scu-ic1", aspeed_ast2600_scu_ic1_of_init);