On Tue, 03 Jan 2023 14:14:05 +0000, Anup Patel <apatel@xxxxxxxxxxxxxxxx> wrote: > > The RISC-V advanced interrupt architecture (AIA) specification defines > a new MSI controller for managing MSIs on a RISC-V platform. This new > MSI controller is referred to as incoming message signaled interrupt > controller (IMSIC) which manages MSI on per-HART (or per-CPU) basis. > (For more details refer https://github.com/riscv/riscv-aia) And how about IPIs, which this driver seems to be concerned about? > > This patch adds an irqchip driver for RISC-V IMSIC found on RISC-V > platforms. > > Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> > --- > drivers/irqchip/Kconfig | 14 +- > drivers/irqchip/Makefile | 1 + > drivers/irqchip/irq-riscv-imsic.c | 1174 +++++++++++++++++++++++++++ > include/linux/irqchip/riscv-imsic.h | 92 +++ > 4 files changed, 1280 insertions(+), 1 deletion(-) > create mode 100644 drivers/irqchip/irq-riscv-imsic.c > create mode 100644 include/linux/irqchip/riscv-imsic.h > > diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig > index 9e65345ca3f6..a1315189a595 100644 > --- a/drivers/irqchip/Kconfig > +++ b/drivers/irqchip/Kconfig > @@ -29,7 +29,6 @@ config ARM_GIC_V2M > > config GIC_NON_BANKED > bool > - > config ARM_GIC_V3 > bool > select IRQ_DOMAIN_HIERARCHY > @@ -548,6 +547,19 @@ config SIFIVE_PLIC > select IRQ_DOMAIN_HIERARCHY > select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP > > +config RISCV_IMSIC > + bool > + depends on RISCV > + select IRQ_DOMAIN_HIERARCHY > + select GENERIC_MSI_IRQ_DOMAIN > + > +config RISCV_IMSIC_PCI > + bool > + depends on RISCV_IMSIC > + depends on PCI > + depends on PCI_MSI > + default RISCV_IMSIC This should definitely tell you that this driver needs splitting. > + > config EXYNOS_IRQ_COMBINER > bool "Samsung Exynos IRQ combiner support" if COMPILE_TEST > depends on (ARCH_EXYNOS && ARM) || COMPILE_TEST > diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile > index 87b49a10962c..22c723cc6ec8 100644 > --- a/drivers/irqchip/Makefile > +++ b/drivers/irqchip/Makefile > @@ -96,6 +96,7 @@ 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-$(CONFIG_RISCV_IMSIC) += irq-riscv-imsic.o > obj-$(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.c b/drivers/irqchip/irq-riscv-imsic.c > new file mode 100644 > index 000000000000..4c16b66738d6 > --- /dev/null > +++ b/drivers/irqchip/irq-riscv-imsic.c > @@ -0,0 +1,1174 @@ > +// 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/iommu.h> > +#include <linux/irq.h> > +#include <linux/irqchip.h> > +#include <linux/irqchip/chained_irq.h> > +#include <linux/irqchip/riscv-imsic.h> > +#include <linux/irqdomain.h> > +#include <linux/module.h> > +#include <linux/msi.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_irq.h> > +#include <linux/pci.h> > +#include <linux/platform_device.h> > +#include <linux/spinlock.h> > +#include <linux/smp.h> > +#include <asm/hwcap.h> > + > +#define IMSIC_DISABLE_EIDELIVERY 0 > +#define IMSIC_ENABLE_EIDELIVERY 1 > +#define IMSIC_DISABLE_EITHRESHOLD 1 > +#define IMSIC_ENABLE_EITHRESHOLD 0 > + > +#define imsic_csr_write(__c, __v) \ > +do { \ > + csr_write(CSR_ISELECT, __c); \ > + csr_write(CSR_IREG, __v); \ > +} while (0) > + > +#define imsic_csr_read(__c) \ > +({ \ > + unsigned long __v; \ > + csr_write(CSR_ISELECT, __c); \ > + __v = csr_read(CSR_IREG); \ > + __v; \ > +}) > + > +#define imsic_csr_set(__c, __v) \ > +do { \ > + csr_write(CSR_ISELECT, __c); \ > + csr_set(CSR_IREG, __v); \ > +} while (0) > + > +#define imsic_csr_clear(__c, __v) \ > +do { \ > + csr_write(CSR_ISELECT, __c); \ > + csr_clear(CSR_IREG, __v); \ > +} while (0) > + > +struct imsic_mmio { > + phys_addr_t pa; > + void __iomem *va; > + unsigned long size; > +}; > + > +struct imsic_priv { > + /* Global configuration common for all HARTs */ > + struct imsic_global_config global; > + > + /* MMIO regions */ > + u32 num_mmios; > + struct imsic_mmio *mmios; > + > + /* Global state of interrupt identities */ > + raw_spinlock_t ids_lock; > + unsigned long *ids_used_bimap; > + unsigned long *ids_enabled_bimap; > + unsigned int *ids_target_cpu; > + > + /* Mask for connected CPUs */ > + struct cpumask lmask; > + > + /* IPI interrupt identity */ > + u32 ipi_id; > + u32 ipi_lsync_id; > + > + /* IRQ domains */ > + struct irq_domain *base_domain; > + struct irq_domain *pci_domain; > + struct irq_domain *plat_domain; > +}; > + > +struct imsic_handler { > + /* Local configuration for given HART */ > + struct imsic_local_config local; > + > + /* Pointer to private context */ > + struct imsic_priv *priv; > +}; > + > +static bool imsic_init_done; > + > +static int imsic_parent_irq; > +static DEFINE_PER_CPU(struct imsic_handler, imsic_handlers); > + > +const struct imsic_global_config *imsic_get_global_config(void) > +{ > + struct imsic_handler *handler = this_cpu_ptr(&imsic_handlers); > + > + if (!handler || !handler->priv) > + return NULL; > + > + return &handler->priv->global; > +} > +EXPORT_SYMBOL_GPL(imsic_get_global_config); > + > +const struct imsic_local_config *imsic_get_local_config(unsigned int cpu) > +{ > + struct imsic_handler *handler = per_cpu_ptr(&imsic_handlers, cpu); > + > + if (!handler || !handler->priv) > + return NULL; How can this happen? > + > + return &handler->local; > +} > +EXPORT_SYMBOL_GPL(imsic_get_local_config); Why are these symbols exported? They have no user, so they shouldn't even exist here. I also seriously doubt there is a valid use case for exposing this information to the rest of the kernel. > + > +static int imsic_cpu_page_phys(unsigned int cpu, > + unsigned int guest_index, > + phys_addr_t *out_msi_pa) > +{ > + struct imsic_handler *handler = per_cpu_ptr(&imsic_handlers, cpu); > + struct imsic_global_config *global; > + struct imsic_local_config *local; > + > + if (!handler || !handler->priv) > + return -ENODEV; > + local = &handler->local; > + global = &handler->priv->global; > + > + if (BIT(global->guest_index_bits) <= guest_index) > + return -EINVAL; > + > + if (out_msi_pa) > + *out_msi_pa = local->msi_pa + > + (guest_index * IMSIC_MMIO_PAGE_SZ); > + > + return 0; > +} > + > +static int imsic_get_cpu(struct imsic_priv *priv, > + const struct cpumask *mask_val, bool force, > + unsigned int *out_target_cpu) > +{ > + struct cpumask amask; > + unsigned int cpu; > + > + cpumask_and(&amask, &priv->lmask, mask_val); > + > + if (force) > + cpu = cpumask_first(&amask); > + else > + cpu = cpumask_any_and(&amask, cpu_online_mask); > + > + if (cpu >= nr_cpu_ids) > + return -EINVAL; > + > + if (out_target_cpu) > + *out_target_cpu = cpu; > + > + return 0; > +} > + > +static int imsic_get_cpu_msi_msg(unsigned int cpu, unsigned int id, > + struct msi_msg *msg) > +{ > + phys_addr_t msi_addr; > + int err; > + > + err = imsic_cpu_page_phys(cpu, 0, &msi_addr); > + if (err) > + return err; > + > + msg->address_hi = upper_32_bits(msi_addr); > + msg->address_lo = lower_32_bits(msi_addr); > + msg->data = id; > + > + return err; > +} > + > +static void imsic_id_set_target(struct imsic_priv *priv, > + unsigned int id, unsigned int target_cpu) > +{ > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + priv->ids_target_cpu[id] = target_cpu; > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > +} > + > +static unsigned int imsic_id_get_target(struct imsic_priv *priv, > + unsigned int id) > +{ > + unsigned int ret; > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + ret = priv->ids_target_cpu[id]; > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > + > + return ret; > +} > + > +static void __imsic_eix_update(unsigned long base_id, > + unsigned long num_id, bool pend, bool val) > +{ > + unsigned long i, isel, ireg, flags; > + unsigned long id = base_id, last_id = base_id + num_id; > + > + while (id < last_id) { > + isel = id / BITS_PER_LONG; > + isel *= BITS_PER_LONG / IMSIC_EIPx_BITS; > + isel += (pend) ? IMSIC_EIP0 : IMSIC_EIE0; > + > + ireg = 0; > + for (i = id & (__riscv_xlen - 1); > + (id < last_id) && (i < __riscv_xlen); i++) { > + ireg |= BIT(i); > + id++; > + } > + > + /* > + * The IMSIC EIEx and EIPx registers are indirectly > + * accessed via using ISELECT and IREG CSRs so we > + * save/restore local IRQ to ensure that we don't > + * get preempted while accessing IMSIC registers. > + */ > + local_irq_save(flags); > + if (val) > + imsic_csr_set(isel, ireg); > + else > + imsic_csr_clear(isel, ireg); > + local_irq_restore(flags); What is the actual requirement? no preemption? or no interrupts? This isn't the same thing. Also, a bunch of the users already disable interrupts. Consistency wouldn't hurt here. > + } > +} > + > +#define __imsic_id_enable(__id) \ > + __imsic_eix_update((__id), 1, false, true) > +#define __imsic_id_disable(__id) \ > + __imsic_eix_update((__id), 1, false, false) > + > +#ifdef CONFIG_SMP > +static void __imsic_id_smp_sync(struct imsic_priv *priv) > +{ > + struct imsic_handler *handler; > + struct cpumask amask; > + int cpu; > + > + cpumask_and(&amask, &priv->lmask, cpu_online_mask); Can't this race against a CPU going down? > + for_each_cpu(cpu, &amask) { > + if (cpu == smp_processor_id()) > + continue; > + > + handler = per_cpu_ptr(&imsic_handlers, cpu); > + if (!handler || !handler->priv || !handler->local.msi_va) { > + pr_warn("CPU%d: handler not initialized\n", cpu); How many times are you going to do that? On each failing synchronisation? > + continue; > + } > + > + writel(handler->priv->ipi_lsync_id, handler->local.msi_va); As I understand it, this is a "behind the scenes" IPI. Why isn't that a *real* IPI? > + } > +} > +#else > +#define __imsic_id_smp_sync(__priv) > +#endif > + > +static void imsic_id_enable(struct imsic_priv *priv, unsigned int id) > +{ > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + bitmap_set(priv->ids_enabled_bimap, id, 1); > + __imsic_id_enable(id); > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > + > + __imsic_id_smp_sync(priv); > +} > + > +static void imsic_id_disable(struct imsic_priv *priv, unsigned int id) > +{ > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + bitmap_clear(priv->ids_enabled_bimap, id, 1); > + __imsic_id_disable(id); > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > + > + __imsic_id_smp_sync(priv); > +} > + > +static void imsic_ids_local_sync(struct imsic_priv *priv) > +{ > + int i; > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + for (i = 1; i <= priv->global.nr_ids; i++) { > + if (priv->ipi_id == i || priv->ipi_lsync_id == i) > + continue; > + > + if (test_bit(i, priv->ids_enabled_bimap)) > + __imsic_id_enable(i); > + else > + __imsic_id_disable(i); > + } > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > +} > + > +static void imsic_ids_local_delivery(struct imsic_priv *priv, bool enable) > +{ > + if (enable) { > + imsic_csr_write(IMSIC_EITHRESHOLD, IMSIC_ENABLE_EITHRESHOLD); > + imsic_csr_write(IMSIC_EIDELIVERY, IMSIC_ENABLE_EIDELIVERY); > + } else { > + imsic_csr_write(IMSIC_EIDELIVERY, IMSIC_DISABLE_EIDELIVERY); > + imsic_csr_write(IMSIC_EITHRESHOLD, IMSIC_DISABLE_EITHRESHOLD); > + } > +} > + > +static int imsic_ids_alloc(struct imsic_priv *priv, > + unsigned int max_id, unsigned int order) > +{ > + int ret; > + unsigned long flags; > + > + if ((priv->global.nr_ids < max_id) || > + (max_id < BIT(order))) > + return -EINVAL; Why do we need this check? Shouldn't that be guaranteed by construction? > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + ret = bitmap_find_free_region(priv->ids_used_bimap, > + max_id + 1, order); > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > + > + return ret; > +} > + > +static void imsic_ids_free(struct imsic_priv *priv, unsigned int base_id, > + unsigned int order) > +{ > + unsigned long flags; > + > + raw_spin_lock_irqsave(&priv->ids_lock, flags); > + bitmap_release_region(priv->ids_used_bimap, base_id, order); > + raw_spin_unlock_irqrestore(&priv->ids_lock, flags); > +} > + > +static int __init imsic_ids_init(struct imsic_priv *priv) > +{ > + int i; > + struct imsic_global_config *global = &priv->global; > + > + raw_spin_lock_init(&priv->ids_lock); > + > + /* Allocate used bitmap */ > + priv->ids_used_bimap = kcalloc(BITS_TO_LONGS(global->nr_ids + 1), > + sizeof(unsigned long), GFP_KERNEL); How about bitmap_alloc? > + if (!priv->ids_used_bimap) > + return -ENOMEM; > + > + /* Allocate enabled bitmap */ > + priv->ids_enabled_bimap = kcalloc(BITS_TO_LONGS(global->nr_ids + 1), > + sizeof(unsigned long), GFP_KERNEL); > + if (!priv->ids_enabled_bimap) { > + kfree(priv->ids_used_bimap); > + return -ENOMEM; > + } > + > + /* Allocate target CPU array */ > + priv->ids_target_cpu = kcalloc(global->nr_ids + 1, > + sizeof(unsigned int), GFP_KERNEL); > + if (!priv->ids_target_cpu) { > + kfree(priv->ids_enabled_bimap); > + kfree(priv->ids_used_bimap); > + return -ENOMEM; > + } > + for (i = 0; i <= global->nr_ids; i++) > + priv->ids_target_cpu[i] = UINT_MAX; > + > + /* Reserve ID#0 because it is special and never implemented */ > + bitmap_set(priv->ids_used_bimap, 0, 1); > + > + return 0; > +} > + > +static void __init imsic_ids_cleanup(struct imsic_priv *priv) > +{ > + kfree(priv->ids_target_cpu); > + kfree(priv->ids_enabled_bimap); > + kfree(priv->ids_used_bimap); > +} > + > +#ifdef CONFIG_SMP > +static void imsic_ipi_send(unsigned int cpu) > +{ > + struct imsic_handler *handler = per_cpu_ptr(&imsic_handlers, cpu); > + > + if (!handler || !handler->priv || !handler->local.msi_va) { > + pr_warn("CPU%d: handler not initialized\n", cpu); > + return; > + } > + > + writel(handler->priv->ipi_id, handler->local.msi_va); > +} > + > +static void imsic_ipi_enable(struct imsic_priv *priv) > +{ > + __imsic_id_enable(priv->ipi_id); > + __imsic_id_enable(priv->ipi_lsync_id); > +} > + > +static int __init imsic_ipi_domain_init(struct imsic_priv *priv) > +{ > + int virq; > + > + /* Allocate interrupt identity for IPIs */ > + virq = imsic_ids_alloc(priv, priv->global.nr_ids, get_count_order(1)); > + if (virq < 0) > + return virq; > + priv->ipi_id = virq; > + > + /* Create IMSIC IPI multiplexing */ > + virq = ipi_mux_create(BITS_PER_BYTE, imsic_ipi_send); Please! This BITS_PER_BYTE makes zero sense here. Have a proper define that says 8, and document *why* this is 8! You're not defining a type system, you're writing a irqchip driver. > + if (virq <= 0) { > + imsic_ids_free(priv, priv->ipi_id, get_count_order(1)); > + return (virq < 0) ? virq : -ENOMEM; > + } > + > + /* Set vIRQ range */ > + riscv_ipi_set_virq_range(virq, BITS_PER_BYTE, true); > + > + /* Allocate interrupt identity for local enable/disable sync */ > + virq = imsic_ids_alloc(priv, priv->global.nr_ids, get_count_order(1)); > + if (virq < 0) { > + imsic_ids_free(priv, priv->ipi_id, get_count_order(1)); > + return virq; > + } > + priv->ipi_lsync_id = virq; > + > + return 0; > +} > + > +static void __init imsic_ipi_domain_cleanup(struct imsic_priv *priv) > +{ > + imsic_ids_free(priv, priv->ipi_lsync_id, get_count_order(1)); > + if (priv->ipi_id) > + imsic_ids_free(priv, priv->ipi_id, get_count_order(1)); > +} > +#else > +static void imsic_ipi_enable(struct imsic_priv *priv) > +{ > +} > + > +static int __init imsic_ipi_domain_init(struct imsic_priv *priv) > +{ > + /* Clear the IPI ids because we are not using IPIs */ > + priv->ipi_id = 0; > + priv->ipi_lsync_id = 0; > + return 0; > +} > + > +static void __init imsic_ipi_domain_cleanup(struct imsic_priv *priv) > +{ > +} > +#endif > + > +static void imsic_irq_mask(struct irq_data *d) > +{ > + imsic_id_disable(irq_data_get_irq_chip_data(d), d->hwirq); > +} > + > +static void imsic_irq_unmask(struct irq_data *d) > +{ > + imsic_id_enable(irq_data_get_irq_chip_data(d), d->hwirq); > +} > + > +static void imsic_irq_compose_msi_msg(struct irq_data *d, > + struct msi_msg *msg) > +{ > + struct imsic_priv *priv = irq_data_get_irq_chip_data(d); > + unsigned int cpu; > + int err; > + > + cpu = imsic_id_get_target(priv, d->hwirq); > + WARN_ON(cpu == UINT_MAX); > + > + err = imsic_get_cpu_msi_msg(cpu, d->hwirq, msg); > + WARN_ON(err); > + > + iommu_dma_compose_msi_msg(irq_data_get_msi_desc(d), msg); > +} > + > +#ifdef CONFIG_SMP > +static int imsic_irq_set_affinity(struct irq_data *d, > + const struct cpumask *mask_val, > + bool force) > +{ > + struct imsic_priv *priv = irq_data_get_irq_chip_data(d); > + unsigned int target_cpu; > + int rc; > + > + rc = imsic_get_cpu(priv, mask_val, force, &target_cpu); > + if (rc) > + return rc; > + > + imsic_id_set_target(priv, d->hwirq, target_cpu); > + irq_data_update_effective_affinity(d, cpumask_of(target_cpu)); > + > + return IRQ_SET_MASK_OK; > +} > +#endif > + > +static struct irq_chip imsic_irq_base_chip = { > + .name = "RISC-V IMSIC-BASE", > + .irq_mask = imsic_irq_mask, > + .irq_unmask = imsic_irq_unmask, > +#ifdef CONFIG_SMP > + .irq_set_affinity = imsic_irq_set_affinity, > +#endif > + .irq_compose_msi_msg = imsic_irq_compose_msi_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_priv *priv = domain->host_data; > + msi_alloc_info_t *info = args; > + phys_addr_t msi_addr; > + int i, hwirq, err = 0; > + unsigned int cpu; > + > + err = imsic_get_cpu(priv, &priv->lmask, false, &cpu); > + if (err) > + return err; > + > + err = imsic_cpu_page_phys(cpu, 0, &msi_addr); > + if (err) > + return err; > + > + hwirq = imsic_ids_alloc(priv, priv->global.nr_ids, > + get_count_order(nr_irqs)); > + if (hwirq < 0) > + return hwirq; > + > + err = iommu_dma_prepare_msi(info->desc, msi_addr); > + if (err) > + goto fail; > + > + for (i = 0; i < nr_irqs; i++) { > + imsic_id_set_target(priv, hwirq + i, cpu); > + irq_domain_set_info(domain, virq + i, hwirq + i, > + &imsic_irq_base_chip, priv, > + handle_simple_irq, NULL, NULL); > + irq_set_noprobe(virq + i); > + irq_set_affinity(virq + i, &priv->lmask); > + } > + > + return 0; > + > +fail: > + imsic_ids_free(priv, hwirq, get_count_order(nr_irqs)); > + return err; > +} > + > +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); > + struct imsic_priv *priv = domain->host_data; > + > + imsic_ids_free(priv, d->hwirq, get_count_order(nr_irqs)); > + irq_domain_free_irqs_parent(domain, virq, nr_irqs); > +} > + > +static const struct irq_domain_ops imsic_base_domain_ops = { > + .alloc = imsic_irq_domain_alloc, > + .free = imsic_irq_domain_free, > +}; > + > +#ifdef CONFIG_RISCV_IMSIC_PCI > + > +static void imsic_pci_mask_irq(struct irq_data *d) > +{ > + pci_msi_mask_irq(d); > + irq_chip_mask_parent(d); > +} > + > +static void imsic_pci_unmask_irq(struct irq_data *d) > +{ > + pci_msi_unmask_irq(d); > + irq_chip_unmask_parent(d); > +} > + > +static struct irq_chip imsic_pci_irq_chip = { > + .name = "RISC-V IMSIC-PCI", > + .irq_mask = imsic_pci_mask_irq, > + .irq_unmask = imsic_pci_unmask_irq, > + .irq_eoi = irq_chip_eoi_parent, > +}; > + > +static struct msi_domain_ops imsic_pci_domain_ops = { > +}; > + > +static struct msi_domain_info imsic_pci_domain_info = { > + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | > + MSI_FLAG_PCI_MSIX | MSI_FLAG_MULTI_PCI_MSI), > + .ops = &imsic_pci_domain_ops, > + .chip = &imsic_pci_irq_chip, > +}; > + > +#endif > + > +static struct irq_chip imsic_plat_irq_chip = { > + .name = "RISC-V IMSIC-PLAT", > +}; > + > +static struct msi_domain_ops imsic_plat_domain_ops = { > +}; > + > +static struct msi_domain_info imsic_plat_domain_info = { > + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), > + .ops = &imsic_plat_domain_ops, > + .chip = &imsic_plat_irq_chip, > +}; > + > +static int __init imsic_irq_domains_init(struct imsic_priv *priv, > + struct fwnode_handle *fwnode) > +{ > + /* Create Base IRQ domain */ > + priv->base_domain = irq_domain_create_tree(fwnode, > + &imsic_base_domain_ops, priv); > + if (!priv->base_domain) { > + pr_err("Failed to create IMSIC base domain\n"); > + return -ENOMEM; > + } > + irq_domain_update_bus_token(priv->base_domain, DOMAIN_BUS_NEXUS); > + > +#ifdef CONFIG_RISCV_IMSIC_PCI > + /* Create PCI MSI domain */ > + priv->pci_domain = pci_msi_create_irq_domain(fwnode, > + &imsic_pci_domain_info, > + priv->base_domain); > + if (!priv->pci_domain) { > + pr_err("Failed to create IMSIC PCI domain\n"); > + irq_domain_remove(priv->base_domain); > + return -ENOMEM; > + } > +#endif > + > + /* Create Platform MSI domain */ > + priv->plat_domain = platform_msi_create_irq_domain(fwnode, > + &imsic_plat_domain_info, > + priv->base_domain); > + if (!priv->plat_domain) { > + pr_err("Failed to create IMSIC platform domain\n"); > + if (priv->pci_domain) > + irq_domain_remove(priv->pci_domain); > + irq_domain_remove(priv->base_domain); > + return -ENOMEM; > + } > + > + return 0; > +} > + > +/* > + * To handle an interrupt, we read the TOPEI CSR and write zero in one > + * instruction. If TOPEI CSR is non-zero then we translate TOPEI.ID to > + * Linux interrupt number and let Linux IRQ subsystem handle it. > + */ > +static void imsic_handle_irq(struct irq_desc *desc) > +{ > + struct imsic_handler *handler = this_cpu_ptr(&imsic_handlers); > + struct irq_chip *chip = irq_desc_get_chip(desc); > + struct imsic_priv *priv = handler->priv; > + irq_hw_number_t hwirq; > + int err; > + > + WARN_ON_ONCE(!handler->priv); > + > + chained_irq_enter(chip, desc); > + > + while ((hwirq = csr_swap(CSR_TOPEI, 0))) { > + hwirq = hwirq >> TOPEI_ID_SHIFT; > + > + if (hwirq == priv->ipi_id) { > +#ifdef CONFIG_SMP > + ipi_mux_process(); > +#endif > + continue; > + } else if (hwirq == priv->ipi_lsync_id) { > + imsic_ids_local_sync(priv); > + continue; > + } > + > + err = generic_handle_domain_irq(priv->base_domain, hwirq); > + if (unlikely(err)) > + pr_warn_ratelimited( > + "hwirq %lu mapping not found\n", hwirq); > + } > + > + chained_irq_exit(chip, desc); > +} > + > +static int imsic_starting_cpu(unsigned int cpu) > +{ > + struct imsic_handler *handler = this_cpu_ptr(&imsic_handlers); > + struct imsic_priv *priv = handler->priv; > + > + /* Enable per-CPU parent interrupt */ > + if (imsic_parent_irq) > + enable_percpu_irq(imsic_parent_irq, > + irq_get_trigger_type(imsic_parent_irq)); Shouldn't that be the default already? > + else > + pr_warn("cpu%d: parent irq not available\n", cpu); And yet continue in sequence? Duh... > + > + /* Enable IPIs */ > + imsic_ipi_enable(priv); > + > + /* > + * Interrupts identities might have been enabled/disabled while > + * this CPU was not running so sync-up local enable/disable state. > + */ > + imsic_ids_local_sync(priv); > + > + /* Locally enable interrupt delivery */ > + imsic_ids_local_delivery(priv, true); > + > + return 0; > +} > + > +struct imsic_fwnode_ops { > + u32 (*nr_parent_irq)(struct fwnode_handle *fwnode, > + void *fwopaque); > + int (*parent_hartid)(struct fwnode_handle *fwnode, > + void *fwopaque, u32 index, > + unsigned long *out_hartid); > + u32 (*nr_mmio)(struct fwnode_handle *fwnode, void *fwopaque); > + int (*mmio_to_resource)(struct fwnode_handle *fwnode, > + void *fwopaque, u32 index, > + struct resource *res); > + void __iomem *(*mmio_map)(struct fwnode_handle *fwnode, > + void *fwopaque, u32 index); > + int (*read_u32)(struct fwnode_handle *fwnode, > + void *fwopaque, const char *prop, u32 *out_val); > + bool (*read_bool)(struct fwnode_handle *fwnode, > + void *fwopaque, const char *prop); > +}; Why do we need this sort of (terrible) indirection? > + > +static int __init imsic_init(struct imsic_fwnode_ops *fwops, > + struct fwnode_handle *fwnode, > + void *fwopaque) > +{ > + struct resource res; > + phys_addr_t base_addr; > + int rc, nr_parent_irqs; > + struct imsic_mmio *mmio; > + struct imsic_priv *priv; > + struct irq_domain *domain; > + struct imsic_handler *handler; > + struct imsic_global_config *global; > + u32 i, tmp, nr_handlers = 0; > + > + if (imsic_init_done) { > + pr_err("%pfwP: already initialized hence ignoring\n", > + fwnode); > + return -ENODEV; > + } > + > + if (!riscv_isa_extension_available(NULL, SxAIA)) { > + pr_err("%pfwP: AIA support not available\n", fwnode); > + return -ENODEV; > + } > + > + priv = kzalloc(sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + global = &priv->global; > + > + /* Find number of parent interrupts */ > + nr_parent_irqs = fwops->nr_parent_irq(fwnode, fwopaque); > + if (!nr_parent_irqs) { > + pr_err("%pfwP: no parent irqs available\n", fwnode); > + return -EINVAL; > + } > + > + /* Find number of guest index bits in MSI address */ > + rc = fwops->read_u32(fwnode, fwopaque, "riscv,guest-index-bits", > + &global->guest_index_bits); > + if (rc) > + global->guest_index_bits = 0; > + tmp = BITS_PER_LONG - IMSIC_MMIO_PAGE_SHIFT; > + if (tmp < global->guest_index_bits) { > + pr_err("%pfwP: guest index bits too big\n", fwnode); > + return -EINVAL; > + } > + > + /* Find number of HART index bits */ > + rc = fwops->read_u32(fwnode, fwopaque, "riscv,hart-index-bits", > + &global->hart_index_bits); > + if (rc) { > + /* Assume default value */ > + global->hart_index_bits = __fls(nr_parent_irqs); > + if (BIT(global->hart_index_bits) < nr_parent_irqs) > + global->hart_index_bits++; > + } > + tmp = BITS_PER_LONG - IMSIC_MMIO_PAGE_SHIFT - > + global->guest_index_bits; > + if (tmp < global->hart_index_bits) { > + pr_err("%pfwP: HART index bits too big\n", fwnode); > + return -EINVAL; > + } > + > + /* Find number of group index bits */ > + rc = fwops->read_u32(fwnode, fwopaque, "riscv,group-index-bits", > + &global->group_index_bits); > + if (rc) > + global->group_index_bits = 0; > + tmp = BITS_PER_LONG - IMSIC_MMIO_PAGE_SHIFT - > + global->guest_index_bits - global->hart_index_bits; > + if (tmp < global->group_index_bits) { > + pr_err("%pfwP: group index bits too big\n", fwnode); > + return -EINVAL; > + } > + > + /* > + * Find first bit position of group index. > + * If not specified assumed the default APLIC-IMSIC configuration. > + */ > + rc = fwops->read_u32(fwnode, fwopaque, "riscv,group-index-shift", > + &global->group_index_shift); > + if (rc) > + global->group_index_shift = IMSIC_MMIO_PAGE_SHIFT * 2; > + tmp = global->group_index_bits + global->group_index_shift - 1; > + if (tmp >= BITS_PER_LONG) { > + pr_err("%pfwP: group index shift too big\n", fwnode); > + return -EINVAL; > + } > + > + /* Find number of interrupt identities */ > + rc = fwops->read_u32(fwnode, fwopaque, "riscv,num-ids", > + &global->nr_ids); > + if (rc) { > + pr_err("%pfwP: number of interrupt identities not found\n", > + fwnode); > + return rc; > + } > + if ((global->nr_ids < IMSIC_MIN_ID) || > + (global->nr_ids >= IMSIC_MAX_ID) || > + ((global->nr_ids & IMSIC_MIN_ID) != IMSIC_MIN_ID)) { > + pr_err("%pfwP: invalid number of interrupt identities\n", > + fwnode); > + return -EINVAL; > + } > + > + /* Find number of guest interrupt identities */ > + if (fwops->read_u32(fwnode, fwopaque, "riscv,num-guest-ids", > + &global->nr_guest_ids)) > + global->nr_guest_ids = global->nr_ids; > + if ((global->nr_guest_ids < IMSIC_MIN_ID) || > + (global->nr_guest_ids >= IMSIC_MAX_ID) || > + ((global->nr_guest_ids & IMSIC_MIN_ID) != IMSIC_MIN_ID)) { > + pr_err("%pfwP: invalid number of guest interrupt identities\n", > + fwnode); > + return -EINVAL; > + } Please split the whole guest stuff out. It is totally unused! I've stopped reading. This needs structure, cleanups and a bit of taste. Not a lot of that here at the moment. M. -- Without deviation from the norm, progress is not possible.
