diff options
Diffstat (limited to 'drivers/irqchip/irq-mvebu-sei.c')
| -rw-r--r-- | drivers/irqchip/irq-mvebu-sei.c | 500 |
1 files changed, 500 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mvebu-sei.c b/drivers/irqchip/irq-mvebu-sei.c new file mode 100644 index 000000000..4ecef6d83 --- /dev/null +++ b/drivers/irqchip/irq-mvebu-sei.c @@ -0,0 +1,500 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "mvebu-sei: " fmt + +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/msi.h> +#include <linux/platform_device.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> + +/* Cause register */ +#define GICP_SECR(idx) (0x0 + ((idx) * 0x4)) +/* Mask register */ +#define GICP_SEMR(idx) (0x20 + ((idx) * 0x4)) +#define GICP_SET_SEI_OFFSET 0x30 + +#define SEI_IRQ_COUNT_PER_REG 32 +#define SEI_IRQ_REG_COUNT 2 +#define SEI_IRQ_COUNT (SEI_IRQ_COUNT_PER_REG * SEI_IRQ_REG_COUNT) +#define SEI_IRQ_REG_IDX(irq_id) ((irq_id) / SEI_IRQ_COUNT_PER_REG) +#define SEI_IRQ_REG_BIT(irq_id) ((irq_id) % SEI_IRQ_COUNT_PER_REG) + +struct mvebu_sei_interrupt_range { + u32 first; + u32 size; +}; + +struct mvebu_sei_caps { + struct mvebu_sei_interrupt_range ap_range; + struct mvebu_sei_interrupt_range cp_range; +}; + +struct mvebu_sei { + struct device *dev; + void __iomem *base; + struct resource *res; + struct irq_domain *sei_domain; + struct irq_domain *ap_domain; + struct irq_domain *cp_domain; + const struct mvebu_sei_caps *caps; + + /* Lock on MSI allocations/releases */ + struct mutex cp_msi_lock; + DECLARE_BITMAP(cp_msi_bitmap, SEI_IRQ_COUNT); + + /* Lock on IRQ masking register */ + raw_spinlock_t mask_lock; +}; + +static void mvebu_sei_ack_irq(struct irq_data *d) +{ + struct mvebu_sei *sei = irq_data_get_irq_chip_data(d); + u32 reg_idx = SEI_IRQ_REG_IDX(d->hwirq); + + writel_relaxed(BIT(SEI_IRQ_REG_BIT(d->hwirq)), + sei->base + GICP_SECR(reg_idx)); +} + +static void mvebu_sei_mask_irq(struct irq_data *d) +{ + struct mvebu_sei *sei = irq_data_get_irq_chip_data(d); + u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq); + unsigned long flags; + + /* 1 disables the interrupt */ + raw_spin_lock_irqsave(&sei->mask_lock, flags); + reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx)); + reg |= BIT(SEI_IRQ_REG_BIT(d->hwirq)); + writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx)); + raw_spin_unlock_irqrestore(&sei->mask_lock, flags); +} + +static void mvebu_sei_unmask_irq(struct irq_data *d) +{ + struct mvebu_sei *sei = irq_data_get_irq_chip_data(d); + u32 reg, reg_idx = SEI_IRQ_REG_IDX(d->hwirq); + unsigned long flags; + + /* 0 enables the interrupt */ + raw_spin_lock_irqsave(&sei->mask_lock, flags); + reg = readl_relaxed(sei->base + GICP_SEMR(reg_idx)); + reg &= ~BIT(SEI_IRQ_REG_BIT(d->hwirq)); + writel_relaxed(reg, sei->base + GICP_SEMR(reg_idx)); + raw_spin_unlock_irqrestore(&sei->mask_lock, flags); +} + +static int mvebu_sei_set_affinity(struct irq_data *d, + const struct cpumask *mask_val, + bool force) +{ + return -EINVAL; +} + +static int mvebu_sei_set_irqchip_state(struct irq_data *d, + enum irqchip_irq_state which, + bool state) +{ + /* We can only clear the pending state by acking the interrupt */ + if (which != IRQCHIP_STATE_PENDING || state) + return -EINVAL; + + mvebu_sei_ack_irq(d); + return 0; +} + +static struct irq_chip mvebu_sei_irq_chip = { + .name = "SEI", + .irq_ack = mvebu_sei_ack_irq, + .irq_mask = mvebu_sei_mask_irq, + .irq_unmask = mvebu_sei_unmask_irq, + .irq_set_affinity = mvebu_sei_set_affinity, + .irq_set_irqchip_state = mvebu_sei_set_irqchip_state, +}; + +static int mvebu_sei_ap_set_type(struct irq_data *data, unsigned int type) +{ + if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_LEVEL_HIGH) + return -EINVAL; + + return 0; +} + +static struct irq_chip mvebu_sei_ap_irq_chip = { + .name = "AP SEI", + .irq_ack = irq_chip_ack_parent, + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, + .irq_set_type = mvebu_sei_ap_set_type, +}; + +static void mvebu_sei_cp_compose_msi_msg(struct irq_data *data, + struct msi_msg *msg) +{ + struct mvebu_sei *sei = data->chip_data; + phys_addr_t set = sei->res->start + GICP_SET_SEI_OFFSET; + + msg->data = data->hwirq + sei->caps->cp_range.first; + msg->address_lo = lower_32_bits(set); + msg->address_hi = upper_32_bits(set); +} + +static int mvebu_sei_cp_set_type(struct irq_data *data, unsigned int type) +{ + if ((type & IRQ_TYPE_SENSE_MASK) != IRQ_TYPE_EDGE_RISING) + return -EINVAL; + + return 0; +} + +static struct irq_chip mvebu_sei_cp_irq_chip = { + .name = "CP SEI", + .irq_ack = irq_chip_ack_parent, + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, + .irq_set_type = mvebu_sei_cp_set_type, + .irq_compose_msi_msg = mvebu_sei_cp_compose_msi_msg, +}; + +static int mvebu_sei_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct mvebu_sei *sei = domain->host_data; + struct irq_fwspec *fwspec = arg; + + /* Not much to do, just setup the irqdata */ + irq_domain_set_hwirq_and_chip(domain, virq, fwspec->param[0], + &mvebu_sei_irq_chip, sei); + + return 0; +} + +static void mvebu_sei_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) +{ + int i; + + for (i = 0; i < nr_irqs; i++) { + struct irq_data *d = irq_domain_get_irq_data(domain, virq + i); + irq_set_handler(virq + i, NULL); + irq_domain_reset_irq_data(d); + } +} + +static const struct irq_domain_ops mvebu_sei_domain_ops = { + .alloc = mvebu_sei_domain_alloc, + .free = mvebu_sei_domain_free, +}; + +static int mvebu_sei_ap_translate(struct irq_domain *domain, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + *hwirq = fwspec->param[0]; + *type = IRQ_TYPE_LEVEL_HIGH; + + return 0; +} + +static int mvebu_sei_ap_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *arg) +{ + struct mvebu_sei *sei = domain->host_data; + struct irq_fwspec fwspec; + unsigned long hwirq; + unsigned int type; + int err; + + mvebu_sei_ap_translate(domain, arg, &hwirq, &type); + + fwspec.fwnode = domain->parent->fwnode; + fwspec.param_count = 1; + fwspec.param[0] = hwirq + sei->caps->ap_range.first; + + err = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); + if (err) + return err; + + irq_domain_set_info(domain, virq, hwirq, + &mvebu_sei_ap_irq_chip, sei, + handle_level_irq, NULL, NULL); + irq_set_probe(virq); + + return 0; +} + +static const struct irq_domain_ops mvebu_sei_ap_domain_ops = { + .translate = mvebu_sei_ap_translate, + .alloc = mvebu_sei_ap_alloc, + .free = irq_domain_free_irqs_parent, +}; + +static void mvebu_sei_cp_release_irq(struct mvebu_sei *sei, unsigned long hwirq) +{ + mutex_lock(&sei->cp_msi_lock); + clear_bit(hwirq, sei->cp_msi_bitmap); + mutex_unlock(&sei->cp_msi_lock); +} + +static int mvebu_sei_cp_domain_alloc(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs, + void *args) +{ + struct mvebu_sei *sei = domain->host_data; + struct irq_fwspec fwspec; + unsigned long hwirq; + int ret; + + /* The software only supports single allocations for now */ + if (nr_irqs != 1) + return -ENOTSUPP; + + mutex_lock(&sei->cp_msi_lock); + hwirq = find_first_zero_bit(sei->cp_msi_bitmap, + sei->caps->cp_range.size); + if (hwirq < sei->caps->cp_range.size) + set_bit(hwirq, sei->cp_msi_bitmap); + mutex_unlock(&sei->cp_msi_lock); + + if (hwirq == sei->caps->cp_range.size) + return -ENOSPC; + + fwspec.fwnode = domain->parent->fwnode; + fwspec.param_count = 1; + fwspec.param[0] = hwirq + sei->caps->cp_range.first; + + ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); + if (ret) + goto free_irq; + + irq_domain_set_info(domain, virq, hwirq, + &mvebu_sei_cp_irq_chip, sei, + handle_edge_irq, NULL, NULL); + + return 0; + +free_irq: + mvebu_sei_cp_release_irq(sei, hwirq); + return ret; +} + +static void mvebu_sei_cp_domain_free(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + struct mvebu_sei *sei = domain->host_data; + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + + if (nr_irqs != 1 || d->hwirq >= sei->caps->cp_range.size) { + dev_err(sei->dev, "Invalid hwirq %lu\n", d->hwirq); + return; + } + + mvebu_sei_cp_release_irq(sei, d->hwirq); + irq_domain_free_irqs_parent(domain, virq, 1); +} + +static const struct irq_domain_ops mvebu_sei_cp_domain_ops = { + .alloc = mvebu_sei_cp_domain_alloc, + .free = mvebu_sei_cp_domain_free, +}; + +static struct irq_chip mvebu_sei_msi_irq_chip = { + .name = "SEI pMSI", + .irq_ack = irq_chip_ack_parent, + .irq_set_type = irq_chip_set_type_parent, +}; + +static struct msi_domain_ops mvebu_sei_msi_ops = { +}; + +static struct msi_domain_info mvebu_sei_msi_domain_info = { + .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS, + .ops = &mvebu_sei_msi_ops, + .chip = &mvebu_sei_msi_irq_chip, +}; + +static void mvebu_sei_handle_cascade_irq(struct irq_desc *desc) +{ + struct mvebu_sei *sei = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); + u32 idx; + + chained_irq_enter(chip, desc); + + for (idx = 0; idx < SEI_IRQ_REG_COUNT; idx++) { + unsigned long irqmap; + int bit; + + irqmap = readl_relaxed(sei->base + GICP_SECR(idx)); + for_each_set_bit(bit, &irqmap, SEI_IRQ_COUNT_PER_REG) { + unsigned long hwirq; + int err; + + hwirq = idx * SEI_IRQ_COUNT_PER_REG + bit; + err = generic_handle_domain_irq(sei->sei_domain, hwirq); + if (unlikely(err)) + dev_warn(sei->dev, "Spurious IRQ detected (hwirq %lu)\n", hwirq); + } + } + + chained_irq_exit(chip, desc); +} + +static void mvebu_sei_reset(struct mvebu_sei *sei) +{ + u32 reg_idx; + + /* Clear IRQ cause registers, mask all interrupts */ + for (reg_idx = 0; reg_idx < SEI_IRQ_REG_COUNT; reg_idx++) { + writel_relaxed(0xFFFFFFFF, sei->base + GICP_SECR(reg_idx)); + writel_relaxed(0xFFFFFFFF, sei->base + GICP_SEMR(reg_idx)); + } +} + +static int mvebu_sei_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct irq_domain *plat_domain; + struct mvebu_sei *sei; + u32 parent_irq; + int ret; + + sei = devm_kzalloc(&pdev->dev, sizeof(*sei), GFP_KERNEL); + if (!sei) + return -ENOMEM; + + sei->dev = &pdev->dev; + + mutex_init(&sei->cp_msi_lock); + raw_spin_lock_init(&sei->mask_lock); + + sei->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sei->base = devm_ioremap_resource(sei->dev, sei->res); + if (IS_ERR(sei->base)) + return PTR_ERR(sei->base); + + /* Retrieve the SEI capabilities with the interrupt ranges */ + sei->caps = of_device_get_match_data(&pdev->dev); + if (!sei->caps) { + dev_err(sei->dev, + "Could not retrieve controller capabilities\n"); + return -EINVAL; + } + + /* + * Reserve the single (top-level) parent SPI IRQ from which all the + * interrupts handled by this driver will be signaled. + */ + parent_irq = irq_of_parse_and_map(node, 0); + if (parent_irq <= 0) { + dev_err(sei->dev, "Failed to retrieve top-level SPI IRQ\n"); + return -ENODEV; + } + + /* Create the root SEI domain */ + sei->sei_domain = irq_domain_create_linear(of_node_to_fwnode(node), + (sei->caps->ap_range.size + + sei->caps->cp_range.size), + &mvebu_sei_domain_ops, + sei); + if (!sei->sei_domain) { + dev_err(sei->dev, "Failed to create SEI IRQ domain\n"); + ret = -ENOMEM; + goto dispose_irq; + } + + irq_domain_update_bus_token(sei->sei_domain, DOMAIN_BUS_NEXUS); + + /* Create the 'wired' domain */ + sei->ap_domain = irq_domain_create_hierarchy(sei->sei_domain, 0, + sei->caps->ap_range.size, + of_node_to_fwnode(node), + &mvebu_sei_ap_domain_ops, + sei); + if (!sei->ap_domain) { + dev_err(sei->dev, "Failed to create AP IRQ domain\n"); + ret = -ENOMEM; + goto remove_sei_domain; + } + + irq_domain_update_bus_token(sei->ap_domain, DOMAIN_BUS_WIRED); + + /* Create the 'MSI' domain */ + sei->cp_domain = irq_domain_create_hierarchy(sei->sei_domain, 0, + sei->caps->cp_range.size, + of_node_to_fwnode(node), + &mvebu_sei_cp_domain_ops, + sei); + if (!sei->cp_domain) { + pr_err("Failed to create CPs IRQ domain\n"); + ret = -ENOMEM; + goto remove_ap_domain; + } + + irq_domain_update_bus_token(sei->cp_domain, DOMAIN_BUS_GENERIC_MSI); + + plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node), + &mvebu_sei_msi_domain_info, + sei->cp_domain); + if (!plat_domain) { + pr_err("Failed to create CPs MSI domain\n"); + ret = -ENOMEM; + goto remove_cp_domain; + } + + mvebu_sei_reset(sei); + + irq_set_chained_handler_and_data(parent_irq, + mvebu_sei_handle_cascade_irq, + sei); + + return 0; + +remove_cp_domain: + irq_domain_remove(sei->cp_domain); +remove_ap_domain: + irq_domain_remove(sei->ap_domain); +remove_sei_domain: + irq_domain_remove(sei->sei_domain); +dispose_irq: + irq_dispose_mapping(parent_irq); + + return ret; +} + +static struct mvebu_sei_caps mvebu_sei_ap806_caps = { + .ap_range = { + .first = 0, + .size = 21, + }, + .cp_range = { + .first = 21, + .size = 43, + }, +}; + +static const struct of_device_id mvebu_sei_of_match[] = { + { + .compatible = "marvell,ap806-sei", + .data = &mvebu_sei_ap806_caps, + }, + {}, +}; + +static struct platform_driver mvebu_sei_driver = { + .probe = mvebu_sei_probe, + .driver = { + .name = "mvebu-sei", + .of_match_table = mvebu_sei_of_match, + }, +}; +builtin_platform_driver(mvebu_sei_driver); |