The Linux platform MSI support allows per-device MSI domains so let us add a platform irqchip driver for RISC-V IMSIC which provides a base IRQ domain with MSI parent support for platform device domains. This driver assumes that the IMSIC state is already initialized by the IMSIC early driver. Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> --- drivers/irqchip/Makefile | 2 +- drivers/irqchip/irq-riscv-imsic-platform.c | 346 +++++++++++++++++++++ drivers/irqchip/irq-riscv-imsic-state.h | 1 + 3 files changed, 348 insertions(+), 1 deletion(-) create mode 100644 drivers/irqchip/irq-riscv-imsic-platform.c diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index d714724387ce..abca445a3229 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -95,7 +95,7 @@ obj-$(CONFIG_QCOM_MPM) += irq-qcom-mpm.o obj-$(CONFIG_CSKY_MPINTC) += irq-csky-mpintc.o obj-$(CONFIG_CSKY_APB_INTC) += irq-csky-apb-intc.o obj-$(CONFIG_RISCV_INTC) += irq-riscv-intc.o -obj-$(CONFIG_RISCV_IMSIC) += irq-riscv-imsic-state.o irq-riscv-imsic-early.o +obj-$(CONFIG_RISCV_IMSIC) += irq-riscv-imsic-state.o irq-riscv-imsic-early.o irq-riscv-imsic-platform.o obj-$(CONFIG_SIFIVE_PLIC) += irq-sifive-plic.o obj-$(CONFIG_IMX_IRQSTEER) += irq-imx-irqsteer.o obj-$(CONFIG_IMX_INTMUX) += irq-imx-intmux.o diff --git a/drivers/irqchip/irq-riscv-imsic-platform.c b/drivers/irqchip/irq-riscv-imsic-platform.c new file mode 100644 index 000000000000..7ee44c493dbc --- /dev/null +++ b/drivers/irqchip/irq-riscv-imsic-platform.c @@ -0,0 +1,346 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Western Digital Corporation or its affiliates. + * Copyright (C) 2022 Ventana Micro Systems Inc. + */ + +#define pr_fmt(fmt) "riscv-imsic: " fmt +#include <linux/bitmap.h> +#include <linux/cpu.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/module.h> +#include <linux/msi.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/smp.h> + +#include "irq-riscv-imsic-state.h" + +static bool imsic_cpu_page_phys(unsigned int cpu, unsigned int guest_index, + phys_addr_t *out_msi_pa) +{ + struct imsic_global_config *global; + struct imsic_local_config *local; + + global = &imsic->global; + local = per_cpu_ptr(global->local, cpu); + + if (BIT(global->guest_index_bits) <= guest_index) + return false; + + if (out_msi_pa) + *out_msi_pa = local->msi_pa + + (guest_index * IMSIC_MMIO_PAGE_SZ); + + return true; +} + +static void imsic_irq_mask(struct irq_data *d) +{ + imsic_vector_mask(irq_data_get_irq_chip_data(d)); +} + +static void imsic_irq_unmask(struct irq_data *d) +{ + imsic_vector_unmask(irq_data_get_irq_chip_data(d)); +} + +static int imsic_irq_retrigger(struct irq_data *d) +{ + struct imsic_vector *vec = irq_data_get_irq_chip_data(d); + struct imsic_local_config *local; + + if (WARN_ON(vec == NULL)) + return -ENOENT; + + local = per_cpu_ptr(imsic->global.local, vec->cpu); + writel_relaxed(vec->local_id, local->msi_va); + return 0; +} + +static void imsic_irq_compose_vector_msg(struct imsic_vector *vec, struct msi_msg *msg) +{ + phys_addr_t msi_addr; + + if (WARN_ON(vec == NULL)) + return; + + if (WARN_ON(!imsic_cpu_page_phys(vec->cpu, 0, &msi_addr))) + return; + + msg->address_hi = upper_32_bits(msi_addr); + msg->address_lo = lower_32_bits(msi_addr); + msg->data = vec->local_id; +} + +static void imsic_irq_compose_msg(struct irq_data *d, struct msi_msg *msg) +{ + imsic_irq_compose_vector_msg(irq_data_get_irq_chip_data(d), msg); +} + +#ifdef CONFIG_SMP +static void imsic_msi_update_msg(struct irq_data *d, struct imsic_vector *vec) +{ + struct msi_msg msg[2] = { [1] = { }, }; + + imsic_irq_compose_vector_msg(vec, msg); + irq_data_get_irq_chip(d)->irq_write_msi_msg(d, msg); +} + +static int imsic_irq_set_affinity(struct irq_data *d, const struct cpumask *mask_val, + bool force) +{ + struct imsic_vector *old_vec, *new_vec; + struct irq_data *pd = d->parent_data; + + old_vec = irq_data_get_irq_chip_data(pd); + if (WARN_ON(old_vec == NULL)) + return -ENOENT; + + /* If old vector cpu belongs to the target cpumask then do nothing */ + if (cpumask_test_cpu(old_vec->cpu, mask_val)) + return IRQ_SET_MASK_OK_DONE; + + /* If move is already in-flight then return failure */ + if (imsic_vector_get_move(old_vec)) + return -EBUSY; + + /* Get a new vector on the desired set of CPUs */ + new_vec = imsic_vector_alloc(old_vec->hwirq, mask_val); + if (!new_vec) + return -ENOSPC; + + /* Point device to the new vector */ + imsic_msi_update_msg(d, new_vec); + + /* Update irq descriptors with the new vector */ + pd->chip_data = new_vec; + + /* Update effective affinity of parent irq data */ + irq_data_update_effective_affinity(pd, cpumask_of(new_vec->cpu)); + + /* Move state of the old vector to the new vector */ + imsic_vector_move(old_vec, new_vec); + + return IRQ_SET_MASK_OK_DONE; +} +#endif + +static struct irq_chip imsic_irq_base_chip = { + .name = "IMSIC", + .irq_mask = imsic_irq_mask, + .irq_unmask = imsic_irq_unmask, + .irq_retrigger = imsic_irq_retrigger, + .irq_compose_msi_msg = imsic_irq_compose_msg, + .flags = IRQCHIP_SKIP_SET_WAKE | + IRQCHIP_MASK_ON_SUSPEND, +}; + +static int imsic_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct imsic_vector *vec; + + /* Legacy-MSI or multi-MSI not supported yet. */ + if (nr_irqs > 1) + return -ENOTSUPP; + + vec = imsic_vector_alloc(virq, cpu_online_mask); + if (!vec) + return -ENOSPC; + + irq_domain_set_info(domain, virq, virq, + &imsic_irq_base_chip, vec, + handle_simple_irq, NULL, NULL); + irq_set_noprobe(virq); + irq_set_affinity(virq, cpu_online_mask); + + return 0; +} + +static void imsic_irq_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) +{ + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + + imsic_vector_free(irq_data_get_irq_chip_data(d)); + irq_domain_free_irqs_parent(domain, virq, nr_irqs); +} + +static int imsic_irq_domain_select(struct irq_domain *domain, struct irq_fwspec *fwspec, + enum irq_domain_bus_token bus_token) +{ + const struct msi_parent_ops *ops = domain->msi_parent_ops; + u32 busmask = BIT(bus_token); + + if (fwspec->fwnode != domain->fwnode || fwspec->param_count != 0) + return 0; + + /* Handle pure domain searches */ + if (bus_token == ops->bus_select_token) + return 1; + + return !!(ops->bus_select_mask & busmask); +} + +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS +static void imsic_irq_debug_show(struct seq_file *m, struct irq_domain *d, + struct irq_data *irqd, int ind) +{ + if (!irqd) { + imsic_vector_debug_show_summary(m, ind); + return; + } + + imsic_vector_debug_show(m, irq_data_get_irq_chip_data(irqd), ind); +} +#endif + +static const struct irq_domain_ops imsic_base_domain_ops = { + .alloc = imsic_irq_domain_alloc, + .free = imsic_irq_domain_free, + .select = imsic_irq_domain_select, +#ifdef CONFIG_GENERIC_IRQ_DEBUGFS + .debug_show = imsic_irq_debug_show, +#endif +}; + +static bool imsic_init_dev_msi_info(struct device *dev, + struct irq_domain *domain, + struct irq_domain *real_parent, + struct msi_domain_info *info) +{ + const struct msi_parent_ops *pops = real_parent->msi_parent_ops; + + /* MSI parent domain specific settings */ + switch (real_parent->bus_token) { + case DOMAIN_BUS_NEXUS: + if (WARN_ON_ONCE(domain != real_parent)) + return false; +#ifdef CONFIG_SMP + info->chip->irq_set_affinity = imsic_irq_set_affinity; +#endif + break; + default: + WARN_ON_ONCE(1); + return false; + } + + /* Is the target supported? */ + switch (info->bus_token) { + case DOMAIN_BUS_DEVICE_MSI: + /* + * Per-device MSI should never have any MSI feature bits + * set. It's sole purpose is to create a dumb interrupt + * chip which has a device specific irq_write_msi_msg() + * callback. + */ + if (WARN_ON_ONCE(info->flags)) + return false; + + /* Core managed MSI descriptors */ + info->flags |= MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | + MSI_FLAG_FREE_MSI_DESCS; + break; + case DOMAIN_BUS_WIRED_TO_MSI: + break; + default: + WARN_ON_ONCE(1); + return false; + } + + /* Use hierarchial chip operations re-trigger */ + info->chip->irq_retrigger = irq_chip_retrigger_hierarchy; + + /* + * Mask out the domain specific MSI feature flags which are not + * supported by the real parent. + */ + info->flags &= pops->supported_flags; + + /* Enforce the required flags */ + info->flags |= pops->required_flags; + + return true; +} + +#define MATCH_PLATFORM_MSI BIT(DOMAIN_BUS_PLATFORM_MSI) + +static const struct msi_parent_ops imsic_msi_parent_ops = { + .supported_flags = MSI_GENERIC_FLAGS_MASK, + .required_flags = MSI_FLAG_USE_DEF_DOM_OPS | + MSI_FLAG_USE_DEF_CHIP_OPS, + .bus_select_token = DOMAIN_BUS_NEXUS, + .bus_select_mask = MATCH_PLATFORM_MSI, + .init_dev_msi_info = imsic_init_dev_msi_info, +}; + +int imsic_irqdomain_init(void) +{ + struct imsic_global_config *global; + + if (!imsic || !imsic->fwnode) { + pr_err("early driver not probed\n"); + return -ENODEV; + } + + if (imsic->base_domain) { + pr_err("%pfwP: irq domain already created\n", imsic->fwnode); + return -ENODEV; + } + + /* Create Base IRQ domain */ + imsic->base_domain = irq_domain_create_tree(imsic->fwnode, + &imsic_base_domain_ops, imsic); + if (!imsic->base_domain) { + pr_err("%pfwP: failed to create IMSIC base domain\n", + imsic->fwnode); + return -ENOMEM; + } + imsic->base_domain->flags |= IRQ_DOMAIN_FLAG_MSI_PARENT; + imsic->base_domain->msi_parent_ops = &imsic_msi_parent_ops; + + irq_domain_update_bus_token(imsic->base_domain, DOMAIN_BUS_NEXUS); + + global = &imsic->global; + pr_info("%pfwP: hart-index-bits: %d, guest-index-bits: %d\n", + imsic->fwnode, global->hart_index_bits, global->guest_index_bits); + pr_info("%pfwP: group-index-bits: %d, group-index-shift: %d\n", + imsic->fwnode, global->group_index_bits, global->group_index_shift); + pr_info("%pfwP: per-CPU IDs %d at base PPN %pa\n", + imsic->fwnode, global->nr_ids, &global->base_addr); + pr_info("%pfwP: total %d interrupts available\n", + imsic->fwnode, num_possible_cpus() * (global->nr_ids - 1)); + + return 0; +} + +static int imsic_platform_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + + if (imsic && imsic->fwnode != dev->fwnode) { + dev_err(dev, "fwnode mismatch\n"); + return -ENODEV; + } + + return imsic_irqdomain_init(); +} + +static const struct of_device_id imsic_platform_match[] = { + { .compatible = "riscv,imsics" }, + {} +}; + +static struct platform_driver imsic_platform_driver = { + .driver = { + .name = "riscv-imsic", + .of_match_table = imsic_platform_match, + }, + .probe = imsic_platform_probe, +}; +builtin_platform_driver(imsic_platform_driver); diff --git a/drivers/irqchip/irq-riscv-imsic-state.h b/drivers/irqchip/irq-riscv-imsic-state.h index f0c983db99eb..a01a70eff3af 100644 --- a/drivers/irqchip/irq-riscv-imsic-state.h +++ b/drivers/irqchip/irq-riscv-imsic-state.h @@ -94,5 +94,6 @@ void imsic_vector_debug_show_summary(struct seq_file *m, int ind); void imsic_state_online(void); void imsic_state_offline(void); int imsic_setup_state(struct fwnode_handle *fwnode); +int imsic_irqdomain_init(void); #endif -- 2.34.1