From 04f605906ff00c649751519ca73d3058372cdc78 Mon Sep 17 00:00:00 2001 From: Eddie James Date: Wed, 15 Jan 2020 15:29:40 -0600 Subject: [PATCH] irqchip: Add Aspeed SCU interrupt controller The Aspeed SOCs provide some interrupts through the System Control Unit registers. Add an interrupt controller that provides these interrupts to the system. Signed-off-by: Eddie James Signed-off-by: Marc Zyngier Reviewed-by: Andrew Jeffery Link: https://lore.kernel.org/r/1579123790-6894-3-git-send-email-eajames@linux.ibm.com --- MAINTAINERS | 1 + drivers/irqchip/Makefile | 2 +- drivers/irqchip/irq-aspeed-scu-ic.c | 239 ++++++++++++++++++++++++++++ 3 files changed, 241 insertions(+), 1 deletion(-) create mode 100644 drivers/irqchip/irq-aspeed-scu-ic.c diff --git a/MAINTAINERS b/MAINTAINERS index f9f6e4060a92..ac21e7b779c9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2697,6 +2697,7 @@ M: Eddie James L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers) S: Maintained F: Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2xxx-scu-ic.txt +F: drivers/irqchip/irq-aspeed-scu-ic.c F: include/dt-bindings/interrupt-controller/aspeed-scu-ic.h ASPEED VIDEO ENGINE DRIVER diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index e806dda690ea..6c9262c673bf 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -87,7 +87,7 @@ obj-$(CONFIG_MVEBU_SEI) += irq-mvebu-sei.o obj-$(CONFIG_LS_EXTIRQ) += irq-ls-extirq.o obj-$(CONFIG_LS_SCFG_MSI) += irq-ls-scfg-msi.o obj-$(CONFIG_EZNPS_GIC) += irq-eznps.o -obj-$(CONFIG_ARCH_ASPEED) += irq-aspeed-vic.o irq-aspeed-i2c-ic.o +obj-$(CONFIG_ARCH_ASPEED) += irq-aspeed-vic.o irq-aspeed-i2c-ic.o irq-aspeed-scu-ic.o obj-$(CONFIG_STM32_EXTI) += irq-stm32-exti.o obj-$(CONFIG_QCOM_IRQ_COMBINER) += qcom-irq-combiner.o obj-$(CONFIG_IRQ_UNIPHIER_AIDET) += irq-uniphier-aidet.o diff --git a/drivers/irqchip/irq-aspeed-scu-ic.c b/drivers/irqchip/irq-aspeed-scu-ic.c new file mode 100644 index 000000000000..c90a3346b985 --- /dev/null +++ b/drivers/irqchip/irq-aspeed-scu-ic.c @@ -0,0 +1,239 @@ +// 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 irq; + 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) { + irq = irq_find_mapping(scu_ic->irq_domain, + bit - scu_ic->irq_shift); + generic_handle_irq(irq); + + regmap_update_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 < 0) { + rc = irq; + 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);