[PATCH v4 08/10] irqchip: Add RISC-V advanced PLIC driver

Saravana Kannan saravanak at google.com
Thu Jun 22 13:56:50 PDT 2023


On Sun, Jun 18, 2023 at 11:13 PM Anup Patel <apatel at ventanamicro.com> wrote:
>
> On Sat, Jun 17, 2023 at 3:36 AM Saravana Kannan <saravanak at google.com> wrote:
> >
> > On Thu, Jun 15, 2023 at 7:01 PM Anup Patel <anup at brainfault.org> wrote:
> > >
> > > On Fri, Jun 16, 2023 at 12:47 AM Saravana Kannan <saravanak at google.com> wrote:
> > > >
> > > > On Tue, Jun 13, 2023 at 8:35 AM Anup Patel <apatel at ventanamicro.com> wrote:
> > > > >
> > > > > 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 at ventanamicro.com>
> > > > > ---
> > > > >  drivers/irqchip/Kconfig             |   6 +
> > > > >  drivers/irqchip/Makefile            |   1 +
> > > > >  drivers/irqchip/irq-riscv-aplic.c   | 765 ++++++++++++++++++++++++++++
> > > > >  include/linux/irqchip/riscv-aplic.h | 119 +++++
> > > > >  4 files changed, 891 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..1e710fdf5608
> > > > > --- /dev/null
> > > > > +++ b/drivers/irqchip/irq-riscv-aplic.c
> > > > > @@ -0,0 +1,765 @@
> > > > > +// 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,
> > > > > +};
> > > > > +builtin_platform_driver(aplic_driver);
> > > > > +
> > > > > +static int __init aplic_dt_init(struct device_node *node,
> > > > > +                               struct device_node *parent)
> > > > > +{
> > > > > +       /*
> > > > > +        * The APLIC platform driver needs to be probed early
> > > > > +        * so for device tree:
> > > > > +        *
> > > > > +        * 1) Set the FWNODE_FLAG_BEST_EFFORT flag in fwnode which
> > > > > +        *    provides a hint to the device driver core to probe the
> > > > > +        *    platform driver early.
> > > > > +        * 2) Clear the OF_POPULATED flag in device_node because
> > > > > +        *    of_irq_init() sets it which prevents creation of
> > > > > +        *    platform device.
> > > > > +        */
> > > > > +       node->fwnode.flags |= FWNODE_FLAG_BEST_EFFORT;
> > > >
> > > > NACK. You are blindly plastering flags without trying to understand
> > > > the real issue and fixing this correctly.
> > > >
> > > > > +       of_node_clear_flag(node, OF_POPULATED);
> > > > > +       return 0;
> > > > > +}
> > > > > +IRQCHIP_DECLARE(riscv_aplic, "riscv,aplic", aplic_dt_init);
> > > >
> > > > This macro pretty much skips the entire driver core framework to probe
> > > > and calls init and you are supposed to initialize the device when the
> > > > init function is called.
> > > >
> > > > If you want your device/driver to follow the proper platform driver
> > > > path (which is recommended), then you need to use the
> > > > IRQCHIP_PLATFORM_DRIVER_BEGIN() and related macros. Grep for plenty of examples.
> > > >
> > > > I offered to help you debug this issue and I asked for a dts file that
> > > > corresponds to a board you are testing this on and seeing an issue.
> > > > But you haven't answered my question [1] and are pointing to some
> > > > random commit and blaming it. That commit has no impact on any
> > > > existing devices/drivers.
> > > >
> > > > Hi Marc,
> > > >
> > > > Please consider this patch Nacked as long as FWNODE_FLAG_BEST_EFFORT
> > > > is used or until Anup actually works with us to debug the real issue.
> > >
> > > Maybe I misread your previous comment.
> > >
> > > You can easily reproduce the issue on QEMU virt machine for RISC-V:
> > > 1) Build qemu-system-riscv64 from latest QEMU master
> > > 2) Build kernel from riscv_aia_v4 branch at https://github.com/avpatel/linux.git
> > > (Note: make sure you remove the FWNODE_FLAG_BEST_EFFORT flag from
> > >  APLIC driver at the time of building kernel)
> > > 3) Boot a APLIC-only system on QEMU virt machine
> > >     qemu-system-riscv64 -smp 4 -M virt,aia=aplic -m 1G -nographic \
> > >     -bios opensbi/build/platform/generic/firmware/fw_dynamic.bin \
> > >     -kernel ./build-riscv64/arch/riscv/boot/Image \
> > >     -append "root=/dev/ram rw console=ttyS0 earlycon" \
> > >     -initrd ./rootfs_riscv64.img
> >
> > Unfortunately, I don't have the time to do all that, but I generally
> > don't need to run something to figure out the issue. It's generally
> > fairly obvious once I look at the DT. I'll also lean on you for some
> > debug logs.
>
> The boot log with FWNODE_BEST_EFFORT flag in APLIC can be
> found at:
> https://drive.google.com/file/d/1C-uuHbh6Zk9xkAsfGLfhb_4WighvmQp1/view?usp=sharing
>
> The boot log without FWNODE_BEST_EFFORT flag in APLIC can
> be found at:
> https://drive.google.com/file/d/12SRdR-2Frv_5O06kbuI_LUJ88khjf_7O/view?usp=sharing
>
> >
> > Where is the dts file that corresponds to this QEMU run? This is the
> > third time I'm asking for a pointer to a dts file that has this issue,
> > can you point me to it please? I shouldn't have to say this but: put
> > it somewhere and point me to it please. Please don't point me to some
> > git repo and ask me to dig around.
>
> For QEMU virt machine, the DTB is generated at runtime as part of
> virt machine creation. The DTS dumped by QEMU using the "dumpdtb"
> command line option can be found at:
> https://drive.google.com/file/d/1EU-exItL1B7EWuoXw4q-Ypocq--5Wvn8/view?usp=sharing
>
> >
> > Can you give me details on what supplier is causing the deferred probe
> > that's a problem for you? Any other details you can provide that'll
> > help debug this issue?
>
> FWNODE supplier for APLIC DT node is the OF framework.
>
> >
> > > I hope the above steps help you reproduce the issue. I will certainly
> > > test whatever fix you propose.
> >
> > Do you plan to try the fix I suggested already? The one about using
> > the correct macros?
>
> You mean use IRQCHIP_DECLARE() in the APLIC driver ?
> or something else ?

No. My previous email asking you to NOT use IRQCHIP_DECLARE() and
instead use IRQCHIP_PLATFORM_DRIVER_BEGIN/END() macros.

-Saravana



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