[PATCH v3 09/11] irqchip: Add RISC-V advanced PLIC driver

Anup Patel
2023-05-08T14:30:44Z

The RISC-V advanced interrupt architecture (AIA) specification defines
a new interrupt controller for managing wired interrupts on a RISC-V
platform. This new interrupt controller is referred to as advanced
platform-level interrupt controller (APLIC) which can forward wired
interrupts to CPUs (or HARTs) as local interrupts OR as message
signaled interrupts.
(For more details refer https://github.com/riscv/riscv-aia)

This patch adds an irqchip driver for RISC-V APLIC found on RISC-V
platforms.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
drivers/irqchip/Kconfig | 6 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-riscv-aplic.c | 750 ++++++++++++++++++++++++++++
include/linux/irqchip/riscv-aplic.h | 119 +++++
4 files changed, 876 insertions(+)
create mode 100644 drivers/irqchip/irq-riscv-aplic.c
create mode 100644 include/linux/irqchip/riscv-aplic.h

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index d700980372ef..834c0329f583 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -544,6 +544,12 @@ config SIFIVE_PLIC
select IRQ_DOMAIN_HIERARCHY
select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP

+config RISCV_APLIC
+ bool
+ depends on RISCV
+ select IRQ_DOMAIN_HIERARCHY
+ select GENERIC_MSI_IRQ
+
config RISCV_IMSIC
bool
depends on RISCV
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 577bde3e986b..438b8e1a152c 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -95,6 +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-$(CONFIG_RISCV_APLIC) += irq-riscv-aplic.o
obj-$(CONFIG_RISCV_IMSIC) += irq-riscv-imsic.o
obj-$(CONFIG_SIFIVE_PLIC) += irq-sifive-plic.o
obj-$(CONFIG_IMX_IRQSTEER) += irq-imx-irqsteer.o
diff --git a/drivers/irqchip/irq-riscv-aplic.c b/drivers/irqchip/irq-riscv-aplic.c
new file mode 100644
index 000000000000..207138ee0e92
--- /dev/null
+++ b/drivers/irqchip/irq-riscv-aplic.c
@@ -0,0 +1,750 @@
+// 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-aplic: " fmt
+#include <linux/bitops.h>
+#include <linux/cpu.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqchip/riscv-aplic.h>
+#include <linux/irqchip/riscv-imsic.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/platform_device.h>
+#include <linux/smp.h>
+
+#define APLIC_DEFAULT_PRIORITY 1
+#define APLIC_DISABLE_IDELIVERY 0
+#define APLIC_ENABLE_IDELIVERY 1
+#define APLIC_DISABLE_ITHRESHOLD 1
+#define APLIC_ENABLE_ITHRESHOLD 0
+
+struct aplic_msicfg {
+ phys_addr_t base_ppn;
+ u32 hhxs;
+ u32 hhxw;
+ u32 lhxs;
+ u32 lhxw;
+};
+
+struct aplic_idc {
+ unsigned int hart_index;
+ void __iomem *regs;
+ struct aplic_priv *priv;
+};
+
+struct aplic_priv {
+ struct fwnode_handle *fwnode;
+ u32 gsi_base;
+ u32 nr_irqs;
+ u32 nr_idcs;
+ void __iomem *regs;
+ struct irq_domain *irqdomain;
+ struct aplic_msicfg msicfg;
+ struct cpumask lmask;
+};
+
+static unsigned int aplic_idc_parent_irq;
+static DEFINE_PER_CPU(struct aplic_idc, aplic_idcs);
+
+static void aplic_irq_unmask(struct irq_data *d)
+{
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+
+ writel(d->hwirq, priv->regs + APLIC_SETIENUM);
+
+ if (!priv->nr_idcs)
+ irq_chip_unmask_parent(d);
+}
+
+static void aplic_irq_mask(struct irq_data *d)
+{
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+
+ writel(d->hwirq, priv->regs + APLIC_CLRIENUM);
+
+ if (!priv->nr_idcs)
+ irq_chip_mask_parent(d);
+}
+
+static int aplic_set_type(struct irq_data *d, unsigned int type)
+{
+ u32 val = 0;
+ void __iomem *sourcecfg;
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+
+ switch (type) {
+ case IRQ_TYPE_NONE:
+ val = APLIC_SOURCECFG_SM_INACTIVE;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ val = APLIC_SOURCECFG_SM_LEVEL_LOW;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ val = APLIC_SOURCECFG_SM_LEVEL_HIGH;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ val = APLIC_SOURCECFG_SM_EDGE_FALL;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ val = APLIC_SOURCECFG_SM_EDGE_RISE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ sourcecfg = priv->regs + APLIC_SOURCECFG_BASE;
+ sourcecfg += (d->hwirq - 1) * sizeof(u32);
+ writel(val, sourcecfg);
+
+ return 0;
+}
+
+static void aplic_irq_eoi(struct irq_data *d)
+{
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+ u32 reg_off, reg_mask;
+
+ /*
+ * EOI handling only required only for level-triggered
+ * interrupts in APLIC MSI mode.
+ */
+
+ if (priv->nr_idcs)
+ return;
+
+ reg_off = APLIC_CLRIP_BASE + ((d->hwirq / APLIC_IRQBITS_PER_REG) * 4);
+ reg_mask = BIT(d->hwirq % APLIC_IRQBITS_PER_REG);
+ switch (irqd_get_trigger_type(d)) {
+ case IRQ_TYPE_LEVEL_LOW:
+ if (!(readl(priv->regs + reg_off) & reg_mask))
+ writel(d->hwirq, priv->regs + APLIC_SETIPNUM_LE);
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ if (readl(priv->regs + reg_off) & reg_mask)
+ writel(d->hwirq, priv->regs + APLIC_SETIPNUM_LE);
+ break;
+ }
+}
+
+#ifdef CONFIG_SMP
+static int aplic_set_affinity(struct irq_data *d,
+ const struct cpumask *mask_val, bool force)
+{
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+ struct aplic_idc *idc;
+ unsigned int cpu, val;
+ struct cpumask amask;
+ void __iomem *target;
+
+ if (!priv->nr_idcs)
+ return irq_chip_set_affinity_parent(d, mask_val, force);
+
+ 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;
+
+ idc = per_cpu_ptr(&aplic_idcs, cpu);
+ target = priv->regs + APLIC_TARGET_BASE;
+ target += (d->hwirq - 1) * sizeof(u32);
+ val = idc->hart_index & APLIC_TARGET_HART_IDX_MASK;
+ val <<= APLIC_TARGET_HART_IDX_SHIFT;
+ val |= APLIC_DEFAULT_PRIORITY;
+ writel(val, target);
+
+ irq_data_update_effective_affinity(d, cpumask_of(cpu));
+
+ return IRQ_SET_MASK_OK_DONE;
+}
+#endif
+
+static struct irq_chip aplic_chip = {
+ .name = "RISC-V APLIC",
+ .irq_mask = aplic_irq_mask,
+ .irq_unmask = aplic_irq_unmask,
+ .irq_set_type = aplic_set_type,
+ .irq_eoi = aplic_irq_eoi,
+#ifdef CONFIG_SMP
+ .irq_set_affinity = aplic_set_affinity,
+#endif
+ .flags = IRQCHIP_SET_TYPE_MASKED |
+ IRQCHIP_SKIP_SET_WAKE |
+ IRQCHIP_MASK_ON_SUSPEND,
+};
+
+static int aplic_irqdomain_translate(struct irq_fwspec *fwspec,
+ u32 gsi_base,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ if (WARN_ON(fwspec->param_count < 2))
+ return -EINVAL;
+ if (WARN_ON(!fwspec->param[0]))
+ return -EINVAL;
+
+ /* For DT, gsi_base is always zero. */
+ *hwirq = fwspec->param[0] - gsi_base;
+ *type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+
+ WARN_ON(*type == IRQ_TYPE_NONE);
+
+ return 0;
+}
+
+static int aplic_irqdomain_msi_translate(struct irq_domain *d,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ struct aplic_priv *priv = platform_msi_get_host_data(d);
+
+ return aplic_irqdomain_translate(fwspec, priv->gsi_base, hwirq, type);
+}
+
+static int aplic_irqdomain_msi_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *arg)
+{
+ int i, ret;
+ unsigned int type;
+ irq_hw_number_t hwirq;
+ struct irq_fwspec *fwspec = arg;
+ struct aplic_priv *priv = platform_msi_get_host_data(domain);
+
+ ret = aplic_irqdomain_translate(fwspec, priv->gsi_base, &hwirq, &type);
+ if (ret)
+ return ret;
+
+ ret = platform_msi_device_domain_alloc(domain, virq, nr_irqs);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_info(domain, virq + i, hwirq + i,
+ &aplic_chip, priv, handle_fasteoi_irq,
+ NULL, NULL);
+ /*
+ * APLIC does not implement irq_disable() so Linux interrupt
+ * subsystem will take a lazy approach for disabling an APLIC
+ * interrupt. This means APLIC interrupts are left unmasked
+ * upon system suspend and interrupts are not processed
+ * immediately upon system wake up. To tackle this, we disable
+ * the lazy approach for all APLIC interrupts.
+ */
+ irq_set_status_flags(virq + i, IRQ_DISABLE_UNLAZY);
+ }
+
+ return 0;
+}
+
+static const struct irq_domain_ops aplic_irqdomain_msi_ops = {
+ .translate = aplic_irqdomain_msi_translate,
+ .alloc = aplic_irqdomain_msi_alloc,
+ .free = platform_msi_device_domain_free,
+};
+
+static int aplic_irqdomain_idc_translate(struct irq_domain *d,
+ struct irq_fwspec *fwspec,
+ unsigned long *hwirq,
+ unsigned int *type)
+{
+ struct aplic_priv *priv = d->host_data;
+
+ return aplic_irqdomain_translate(fwspec, priv->gsi_base, hwirq, type);
+}
+
+static int aplic_irqdomain_idc_alloc(struct irq_domain *domain,
+ unsigned int virq, unsigned int nr_irqs,
+ void *arg)
+{
+ int i, ret;
+ unsigned int type;
+ irq_hw_number_t hwirq;
+ struct irq_fwspec *fwspec = arg;
+ struct aplic_priv *priv = domain->host_data;
+
+ ret = aplic_irqdomain_translate(fwspec, priv->gsi_base, &hwirq, &type);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_info(domain, virq + i, hwirq + i,
+ &aplic_chip, priv, handle_fasteoi_irq,
+ NULL, NULL);
+ irq_set_affinity(virq + i, &priv->lmask);
+ /* See the reason described in aplic_irqdomain_msi_alloc() */
+ irq_set_status_flags(virq + i, IRQ_DISABLE_UNLAZY);
+ }
+
+ return 0;
+}
+
+static const struct irq_domain_ops aplic_irqdomain_idc_ops = {
+ .translate = aplic_irqdomain_idc_translate,
+ .alloc = aplic_irqdomain_idc_alloc,
+ .free = irq_domain_free_irqs_top,
+};
+
+static void aplic_init_hw_irqs(struct aplic_priv *priv)
+{
+ int i;
+
+ /* Disable all interrupts */
+ for (i = 0; i <= priv->nr_irqs; i += 32)
+ writel(-1U, priv->regs + APLIC_CLRIE_BASE +
+ (i / 32) * sizeof(u32));
+
+ /* Set interrupt type and default priority for all interrupts */
+ for (i = 1; i <= priv->nr_irqs; i++) {
+ writel(0, priv->regs + APLIC_SOURCECFG_BASE +
+ (i - 1) * sizeof(u32));
+ writel(APLIC_DEFAULT_PRIORITY,
+ priv->regs + APLIC_TARGET_BASE +
+ (i - 1) * sizeof(u32));
+ }
+
+ /* Clear APLIC domaincfg */
+ writel(0, priv->regs + APLIC_DOMAINCFG);
+}
+
+static void aplic_init_hw_global(struct aplic_priv *priv)
+{
+ u32 val;
+#ifdef CONFIG_RISCV_M_MODE
+ u32 valH;
+
+ if (!priv->nr_idcs) {
+ val = priv->msicfg.base_ppn;
+ valH = (priv->msicfg.base_ppn >> 32) &
+ APLIC_xMSICFGADDRH_BAPPN_MASK;
+ valH |= (priv->msicfg.lhxw & APLIC_xMSICFGADDRH_LHXW_MASK)
+ << APLIC_xMSICFGADDRH_LHXW_SHIFT;
+ valH |= (priv->msicfg.hhxw & APLIC_xMSICFGADDRH_HHXW_MASK)
+ << APLIC_xMSICFGADDRH_HHXW_SHIFT;
+ valH |= (priv->msicfg.lhxs & APLIC_xMSICFGADDRH_LHXS_MASK)
+ << APLIC_xMSICFGADDRH_LHXS_SHIFT;
+ valH |= (priv->msicfg.hhxs & APLIC_xMSICFGADDRH_HHXS_MASK)
+ << APLIC_xMSICFGADDRH_HHXS_SHIFT;
+ writel(val, priv->regs + APLIC_xMSICFGADDR);
+ writel(valH, priv->regs + APLIC_xMSICFGADDRH);
+ }
+#endif
+
+ /* Setup APLIC domaincfg register */
+ val = readl(priv->regs + APLIC_DOMAINCFG);
+ val |= APLIC_DOMAINCFG_IE;
+ if (!priv->nr_idcs)
+ val |= APLIC_DOMAINCFG_DM;
+ writel(val, priv->regs + APLIC_DOMAINCFG);
+ if (readl(priv->regs + APLIC_DOMAINCFG) != val)
+ pr_warn("%pfwP: unable to write 0x%x in domaincfg\n",
+ priv->fwnode, val);
+}
+
+static void aplic_msi_write_msg(struct msi_desc *desc, struct msi_msg *msg)
+{
+ unsigned int group_index, hart_index, guest_index, val;
+ struct irq_data *d = irq_get_irq_data(desc->irq);
+ struct aplic_priv *priv = irq_data_get_irq_chip_data(d);
+ struct aplic_msicfg *mc = &priv->msicfg;
+ phys_addr_t tppn, tbppn, msg_addr;
+ void __iomem *target;
+
+ /* For zeroed MSI, simply write zero into the target register */
+ if (!msg->address_hi && !msg->address_lo && !msg->data) {
+ target = priv->regs + APLIC_TARGET_BASE;
+ target += (d->hwirq - 1) * sizeof(u32);
+ writel(0, target);
+ return;
+ }
+
+ /* Sanity check on message data */
+ WARN_ON(msg->data > APLIC_TARGET_EIID_MASK);
+
+ /* Compute target MSI address */
+ msg_addr = (((u64)msg->address_hi) << 32) | msg->address_lo;
+ tppn = msg_addr >> APLIC_xMSICFGADDR_PPN_SHIFT;
+
+ /* Compute target HART Base PPN */
+ tbppn = tppn;
+ tbppn &= ~APLIC_xMSICFGADDR_PPN_HART(mc->lhxs);
+ tbppn &= ~APLIC_xMSICFGADDR_PPN_LHX(mc->lhxw, mc->lhxs);
+ tbppn &= ~APLIC_xMSICFGADDR_PPN_HHX(mc->hhxw, mc->hhxs);
+ WARN_ON(tbppn != mc->base_ppn);
+
+ /* Compute target group and hart indexes */
+ group_index = (tppn >> APLIC_xMSICFGADDR_PPN_HHX_SHIFT(mc->hhxs)) &
+ APLIC_xMSICFGADDR_PPN_HHX_MASK(mc->hhxw);
+ hart_index = (tppn >> APLIC_xMSICFGADDR_PPN_LHX_SHIFT(mc->lhxs)) &
+ APLIC_xMSICFGADDR_PPN_LHX_MASK(mc->lhxw);
+ hart_index |= (group_index << mc->lhxw);
+ WARN_ON(hart_index > APLIC_TARGET_HART_IDX_MASK);
+
+ /* Compute target guest index */
+ guest_index = tppn & APLIC_xMSICFGADDR_PPN_HART(mc->lhxs);
+ WARN_ON(guest_index > APLIC_TARGET_GUEST_IDX_MASK);
+
+ /* Update IRQ TARGET register */
+ target = priv->regs + APLIC_TARGET_BASE;
+ target += (d->hwirq - 1) * sizeof(u32);
+ val = (hart_index & APLIC_TARGET_HART_IDX_MASK)
+ << APLIC_TARGET_HART_IDX_SHIFT;
+ val |= (guest_index & APLIC_TARGET_GUEST_IDX_MASK)
+ << APLIC_TARGET_GUEST_IDX_SHIFT;
+ val |= (msg->data & APLIC_TARGET_EIID_MASK);
+ writel(val, target);
+}
+
+static int aplic_setup_msi(struct aplic_priv *priv)
+{
+ struct aplic_msicfg *mc = &priv->msicfg;
+ const struct imsic_global_config *imsic_global;
+
+ /*
+ * The APLIC outgoing MSI config registers assume target MSI
+ * controller to be RISC-V AIA IMSIC controller.
+ */
+ imsic_global = imsic_get_global_config();
+ if (!imsic_global) {
+ pr_err("%pfwP: IMSIC global config not found\n",
+ priv->fwnode);
+ return -ENODEV;
+ }
+
+ /* Find number of guest index bits (LHXS) */
+ mc->lhxs = imsic_global->guest_index_bits;
+ if (APLIC_xMSICFGADDRH_LHXS_MASK < mc->lhxs) {
+ pr_err("%pfwP: IMSIC guest index bits big for APLIC LHXS\n",
+ priv->fwnode);
+ return -EINVAL;
+ }
+
+ /* Find number of HART index bits (LHXW) */
+ mc->lhxw = imsic_global->hart_index_bits;
+ if (APLIC_xMSICFGADDRH_LHXW_MASK < mc->lhxw) {
+ pr_err("%pfwP: IMSIC hart index bits big for APLIC LHXW\n",
+ priv->fwnode);
+ return -EINVAL;
+ }
+
+ /* Find number of group index bits (HHXW) */
+ mc->hhxw = imsic_global->group_index_bits;
+ if (APLIC_xMSICFGADDRH_HHXW_MASK < mc->hhxw) {
+ pr_err("%pfwP: IMSIC group index bits big for APLIC HHXW\n",
+ priv->fwnode);
+ return -EINVAL;
+ }
+
+ /* Find first bit position of group index (HHXS) */
+ mc->hhxs = imsic_global->group_index_shift;
+ if (mc->hhxs < (2 * APLIC_xMSICFGADDR_PPN_SHIFT)) {
+ pr_err("%pfwP: IMSIC group index shift should be >= %d\n",
+ priv->fwnode, (2 * APLIC_xMSICFGADDR_PPN_SHIFT));
+ return -EINVAL;
+ }
+ mc->hhxs -= (2 * APLIC_xMSICFGADDR_PPN_SHIFT);
+ if (APLIC_xMSICFGADDRH_HHXS_MASK < mc->hhxs) {
+ pr_err("%pfwP: IMSIC group index shift big for APLIC HHXS\n",
+ priv->fwnode);
+ return -EINVAL;
+ }
+
+ /* Compute PPN base */
+ mc->base_ppn = imsic_global->base_addr >> APLIC_xMSICFGADDR_PPN_SHIFT;
+ mc->base_ppn &= ~APLIC_xMSICFGADDR_PPN_HART(mc->lhxs);
+ mc->base_ppn &= ~APLIC_xMSICFGADDR_PPN_LHX(mc->lhxw, mc->lhxs);
+ mc->base_ppn &= ~APLIC_xMSICFGADDR_PPN_HHX(mc->hhxw, mc->hhxs);
+
+ /* Use all possible CPUs as lmask */
+ cpumask_copy(&priv->lmask, cpu_possible_mask);
+
+ return 0;
+}
+
+/*
+ * To handle an APLIC IDC interrupts, we just read the CLAIMI register
+ * which will return highest priority pending interrupt and clear the
+ * pending bit of the interrupt. This process is repeated until CLAIMI
+ * register return zero value.
+ */
+static void aplic_idc_handle_irq(struct irq_desc *desc)
+{
+ struct aplic_idc *idc = this_cpu_ptr(&aplic_idcs);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ irq_hw_number_t hw_irq;
+ int irq;
+
+ chained_irq_enter(chip, desc);
+
+ while ((hw_irq = readl(idc->regs + APLIC_IDC_CLAIMI))) {
+ hw_irq = hw_irq >> APLIC_IDC_TOPI_ID_SHIFT;
+ irq = irq_find_mapping(idc->priv->irqdomain, hw_irq);
+
+ if (unlikely(irq <= 0))
+ pr_warn_ratelimited("hw_irq %lu mapping not found\n",
+ hw_irq);
+ else
+ generic_handle_irq(irq);
+ }
+
+ chained_irq_exit(chip, desc);
+}
+
+static void aplic_idc_set_delivery(struct aplic_idc *idc, bool en)
+{
+ u32 de = (en) ? APLIC_ENABLE_IDELIVERY : APLIC_DISABLE_IDELIVERY;
+ u32 th = (en) ? APLIC_ENABLE_ITHRESHOLD : APLIC_DISABLE_ITHRESHOLD;
+
+ /* Priority must be less than threshold for interrupt triggering */
+ writel(th, idc->regs + APLIC_IDC_ITHRESHOLD);
+
+ /* Delivery must be set to 1 for interrupt triggering */
+ writel(de, idc->regs + APLIC_IDC_IDELIVERY);
+}
+
+static int aplic_idc_dying_cpu(unsigned int cpu)
+{
+ if (aplic_idc_parent_irq)
+ disable_percpu_irq(aplic_idc_parent_irq);
+
+ return 0;
+}
+
+static int aplic_idc_starting_cpu(unsigned int cpu)
+{
+ if (aplic_idc_parent_irq)
+ enable_percpu_irq(aplic_idc_parent_irq,
+ irq_get_trigger_type(aplic_idc_parent_irq));
+
+ return 0;
+}
+
+static int aplic_setup_idc(struct aplic_priv *priv)
+{
+ int i, j, rc, cpu, setup_count = 0;
+ struct fwnode_reference_args parent;
+ struct irq_domain *domain;
+ unsigned long hartid;
+ struct aplic_idc *idc;
+ u32 val;
+
+ /* Setup per-CPU IDC and target CPU mask */
+ for (i = 0; i < priv->nr_idcs; i++) {
+ rc = fwnode_property_get_reference_args(priv->fwnode,
+ "interrupts-extended", "#interrupt-cells",
+ 0, i, &parent);
+ if (rc) {
+ pr_warn("%pfwP: parent irq for IDC%d not found\n",
+ priv->fwnode, i);
+ continue;
+ }
+
+ /*
+ * Skip interrupts other than external interrupts for
+ * current privilege level.
+ */
+ if (parent.args[0] != RV_IRQ_EXT)
+ continue;
+
+ rc = riscv_fw_parent_hartid(parent.fwnode, &hartid);
+ if (rc) {
+ pr_warn("%pfwP: invalid hartid for IDC%d\n",
+ priv->fwnode, i);
+ continue;
+ }
+
+ cpu = riscv_hartid_to_cpuid(hartid);
+ if (cpu < 0) {
+ pr_warn("%pfwP: invalid cpuid for IDC%d\n",
+ priv->fwnode, i);
+ continue;
+ }
+
+ cpumask_set_cpu(cpu, &priv->lmask);
+
+ idc = per_cpu_ptr(&aplic_idcs, cpu);
+ idc->hart_index = i;
+ idc->regs = priv->regs + APLIC_IDC_BASE + i * APLIC_IDC_SIZE;
+ idc->priv = priv;
+
+ aplic_idc_set_delivery(idc, true);
+
+ /*
+ * Boot cpu might not have APLIC hart_index = 0 so check
+ * and update target registers of all interrupts.
+ */
+ if (cpu == smp_processor_id() && idc->hart_index) {
+ val = idc->hart_index & APLIC_TARGET_HART_IDX_MASK;
+ val <<= APLIC_TARGET_HART_IDX_SHIFT;
+ val |= APLIC_DEFAULT_PRIORITY;
+ for (j = 1; j <= priv->nr_irqs; j++)
+ writel(val, priv->regs + APLIC_TARGET_BASE +
+ (j - 1) * sizeof(u32));
+ }
+
+ setup_count++;
+ }
+
+ /* Find parent domain and register chained handler */
+ domain = irq_find_matching_fwnode(riscv_get_intc_hwnode(),
+ DOMAIN_BUS_ANY);
+ if (!aplic_idc_parent_irq && domain) {
+ aplic_idc_parent_irq = irq_create_mapping(domain, RV_IRQ_EXT);
+ if (aplic_idc_parent_irq) {
+ irq_set_chained_handler(aplic_idc_parent_irq,
+ aplic_idc_handle_irq);
+
+ /*
+ * Setup CPUHP notifier to enable IDC parent
+ * interrupt on all CPUs
+ */
+ cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
+ "irqchip/riscv/aplic:starting",
+ aplic_idc_starting_cpu,
+ aplic_idc_dying_cpu);
+ }
+ }
+
+ /* Fail if we were not able to setup IDC for any CPU */
+ return (setup_count) ? 0 : -ENODEV;
+}
+
+static int aplic_probe(struct platform_device *pdev)
+{
+ struct fwnode_handle *fwnode = pdev->dev.fwnode;
+ struct fwnode_reference_args parent;
+ struct aplic_priv *priv;
+ struct resource *res;
+ phys_addr_t pa;
+ int rc;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ priv->fwnode = fwnode;
+
+ /* Map the MMIO registers */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ pr_err("%pfwP: failed to get MMIO resource\n", fwnode);
+ return -EINVAL;
+ }
+ priv->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
+ if (!priv->regs) {
+ pr_err("%pfwP: failed map MMIO registers\n", fwnode);
+ return -ENOMEM;
+ }
+
+ /*
+ * Find out GSI base number
+ *
+ * Note: DT does not define "riscv,gsi-base" property so GSI
+ * base is always zero for DT.
+ */
+ rc = fwnode_property_read_u32_array(fwnode, "riscv,gsi-base",
+ &priv->gsi_base, 1);
+ if (rc)
+ priv->gsi_base = 0;
+
+ /* Find out number of interrupt sources */
+ rc = fwnode_property_read_u32_array(fwnode, "riscv,num-sources",
+ &priv->nr_irqs, 1);
+ if (rc) {
+ pr_err("%pfwP: failed to get number of interrupt sources\n",
+ fwnode);
+ return rc;
+ }
+
+ /* Setup initial state APLIC interrupts */
+ aplic_init_hw_irqs(priv);
+
+ /*
+ * Find out number of IDCs based on parent interrupts
+ *
+ * If "msi-parent" property is present then we ignore the
+ * APLIC IDCs which forces the APLIC driver to use MSI mode.
+ */
+ if (!fwnode_property_present(fwnode, "msi-parent")) {
+ while (!fwnode_property_get_reference_args(fwnode,
+ "interrupts-extended", "#interrupt-cells",
+ 0, priv->nr_idcs, &parent))
+ priv->nr_idcs++;
+ }
+
+ /* Setup IDCs or MSIs based on number of IDCs */
+ if (priv->nr_idcs)
+ rc = aplic_setup_idc(priv);
+ else
+ rc = aplic_setup_msi(priv);
+ if (rc) {
+ pr_err("%pfwP: failed setup %s\n",
+ fwnode, priv->nr_idcs ? "IDCs" : "MSIs");
+ return rc;
+ }
+
+ /* Setup global config and interrupt delivery */
+ aplic_init_hw_global(priv);
+
+ /* Create irq domain instance for the APLIC */
+ if (priv->nr_idcs)
+ priv->irqdomain = irq_domain_create_linear(
+ priv->fwnode,
+ priv->nr_irqs + 1,
+ &aplic_irqdomain_idc_ops,
+ priv);
+ else
+ priv->irqdomain = platform_msi_create_device_domain(
+ &pdev->dev,
+ priv->nr_irqs + 1,
+ aplic_msi_write_msg,
+ &aplic_irqdomain_msi_ops,
+ priv);
+ if (!priv->irqdomain) {
+ pr_err("%pfwP: failed to add irq domain\n", priv->fwnode);
+ return -ENOMEM;
+ }
+
+ /* Advertise the interrupt controller */
+ if (priv->nr_idcs) {
+ pr_info("%pfwP: %d interrupts directly connected to %d CPUs\n",
+ priv->fwnode, priv->nr_irqs, priv->nr_idcs);
+ } else {
+ pa = priv->msicfg.base_ppn << APLIC_xMSICFGADDR_PPN_SHIFT;
+ pr_info("%pfwP: %d interrupts forwared to MSI base %pa\n",
+ priv->fwnode, priv->nr_irqs, &pa);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id aplic_match[] = {
+ { .compatible = "riscv,aplic" },
+ {}
+};
+
+static struct platform_driver aplic_driver = {
+ .driver = {
+ .name = "riscv-aplic",
+ .of_match_table = aplic_match,
+ },
+ .probe = aplic_probe,
+};
+
+static int __init aplic_init(void)
+{
+ return platform_driver_register(&aplic_driver);
+}
+core_initcall(aplic_init);
diff --git a/include/linux/irqchip/riscv-aplic.h b/include/linux/irqchip/riscv-aplic.h
new file mode 100644
index 000000000000..97e198ea0109
--- /dev/null
+++ b/include/linux/irqchip/riscv-aplic.h
@@ -0,0 +1,119 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ */
+#ifndef __LINUX_IRQCHIP_RISCV_APLIC_H
+#define __LINUX_IRQCHIP_RISCV_APLIC_H
+
+#include <linux/bitops.h>
+
+#define APLIC_MAX_IDC BIT(14)
+#define APLIC_MAX_SOURCE 1024
+
+#define APLIC_DOMAINCFG 0x0000
+#define APLIC_DOMAINCFG_RDONLY 0x80000000
+#define APLIC_DOMAINCFG_IE BIT(8)
+#define APLIC_DOMAINCFG_DM BIT(2)
+#define APLIC_DOMAINCFG_BE BIT(0)
+
+#define APLIC_SOURCECFG_BASE 0x0004
+#define APLIC_SOURCECFG_D BIT(10)
+#define APLIC_SOURCECFG_CHILDIDX_MASK 0x000003ff
+#define APLIC_SOURCECFG_SM_MASK 0x00000007
+#define APLIC_SOURCECFG_SM_INACTIVE 0x0
+#define APLIC_SOURCECFG_SM_DETACH 0x1
+#define APLIC_SOURCECFG_SM_EDGE_RISE 0x4
+#define APLIC_SOURCECFG_SM_EDGE_FALL 0x5
+#define APLIC_SOURCECFG_SM_LEVEL_HIGH 0x6
+#define APLIC_SOURCECFG_SM_LEVEL_LOW 0x7
+
+#define APLIC_MMSICFGADDR 0x1bc0
+#define APLIC_MMSICFGADDRH 0x1bc4
+#define APLIC_SMSICFGADDR 0x1bc8
+#define APLIC_SMSICFGADDRH 0x1bcc
+
+#ifdef CONFIG_RISCV_M_MODE
+#define APLIC_xMSICFGADDR APLIC_MMSICFGADDR
+#define APLIC_xMSICFGADDRH APLIC_MMSICFGADDRH
+#else
+#define APLIC_xMSICFGADDR APLIC_SMSICFGADDR
+#define APLIC_xMSICFGADDRH APLIC_SMSICFGADDRH
+#endif
+
+#define APLIC_xMSICFGADDRH_L BIT(31)
+#define APLIC_xMSICFGADDRH_HHXS_MASK 0x1f
+#define APLIC_xMSICFGADDRH_HHXS_SHIFT 24
+#define APLIC_xMSICFGADDRH_LHXS_MASK 0x7
+#define APLIC_xMSICFGADDRH_LHXS_SHIFT 20
+#define APLIC_xMSICFGADDRH_HHXW_MASK 0x7
+#define APLIC_xMSICFGADDRH_HHXW_SHIFT 16
+#define APLIC_xMSICFGADDRH_LHXW_MASK 0xf
+#define APLIC_xMSICFGADDRH_LHXW_SHIFT 12
+#define APLIC_xMSICFGADDRH_BAPPN_MASK 0xfff
+
+#define APLIC_xMSICFGADDR_PPN_SHIFT 12
+
+#define APLIC_xMSICFGADDR_PPN_HART(__lhxs) \
+ (BIT(__lhxs) - 1)
+
+#define APLIC_xMSICFGADDR_PPN_LHX_MASK(__lhxw) \
+ (BIT(__lhxw) - 1)
+#define APLIC_xMSICFGADDR_PPN_LHX_SHIFT(__lhxs) \
+ ((__lhxs))
+#define APLIC_xMSICFGADDR_PPN_LHX(__lhxw, __lhxs) \
+ (APLIC_xMSICFGADDR_PPN_LHX_MASK(__lhxw) << \
+ APLIC_xMSICFGADDR_PPN_LHX_SHIFT(__lhxs))
+
+#define APLIC_xMSICFGADDR_PPN_HHX_MASK(__hhxw) \
+ (BIT(__hhxw) - 1)
+#define APLIC_xMSICFGADDR_PPN_HHX_SHIFT(__hhxs) \
+ ((__hhxs) + APLIC_xMSICFGADDR_PPN_SHIFT)
+#define APLIC_xMSICFGADDR_PPN_HHX(__hhxw, __hhxs) \
+ (APLIC_xMSICFGADDR_PPN_HHX_MASK(__hhxw) << \
+ APLIC_xMSICFGADDR_PPN_HHX_SHIFT(__hhxs))
+
+#define APLIC_IRQBITS_PER_REG 32
+
+#define APLIC_SETIP_BASE 0x1c00
+#define APLIC_SETIPNUM 0x1cdc
+
+#define APLIC_CLRIP_BASE 0x1d00
+#define APLIC_CLRIPNUM 0x1ddc
+
+#define APLIC_SETIE_BASE 0x1e00
+#define APLIC_SETIENUM 0x1edc
+
+#define APLIC_CLRIE_BASE 0x1f00
+#define APLIC_CLRIENUM 0x1fdc
+
+#define APLIC_SETIPNUM_LE 0x2000
+#define APLIC_SETIPNUM_BE 0x2004
+
+#define APLIC_GENMSI 0x3000
+
+#define APLIC_TARGET_BASE 0x3004
+#define APLIC_TARGET_HART_IDX_SHIFT 18
+#define APLIC_TARGET_HART_IDX_MASK 0x3fff
+#define APLIC_TARGET_GUEST_IDX_SHIFT 12
+#define APLIC_TARGET_GUEST_IDX_MASK 0x3f
+#define APLIC_TARGET_IPRIO_MASK 0xff
+#define APLIC_TARGET_EIID_MASK 0x7ff
+
+#define APLIC_IDC_BASE 0x4000
+#define APLIC_IDC_SIZE 32
+
+#define APLIC_IDC_IDELIVERY 0x00
+
+#define APLIC_IDC_IFORCE 0x04
+
+#define APLIC_IDC_ITHRESHOLD 0x08
+
+#define APLIC_IDC_TOPI 0x18
+#define APLIC_IDC_TOPI_ID_SHIFT 16
+#define APLIC_IDC_TOPI_ID_MASK 0x3ff
+#define APLIC_IDC_TOPI_PRIO_MASK 0xff
+
+#define APLIC_IDC_CLAIMI 0x1c
+
+#endif
--
2.34.1