Re:Re: Re: [PATCH v11 12/14] irqchip/riscv-aplic: Add support for MSI-mode
From: Ben
Date: Wed Nov 08 2023 - 10:34:05 EST
At 2023-11-08 22:56:59, "Anup Patel" <apatel@xxxxxxxxxxxxxxxx> wrote:
>On Wed, Nov 8, 2023 at 8:23 PM Ben <figure1802@xxxxxxx> wrote:
>>
>> At 2023-11-08 22:43:25, "Anup Patel" <apatel@xxxxxxxxxxxxxxxx> wrote:
>> >On Sat, Nov 4, 2023 at 6:30 AM Ben <figure1802@xxxxxxx> wrote:
>> >>
>> >> At 2023-10-24 01:27:58, "Anup Patel" <apatel@xxxxxxxxxxxxxxxx> wrote:
>> >> >The RISC-V advanced platform-level interrupt controller (APLIC) has
>> >> >two modes of operation: 1) Direct mode and 2) MSI mode.
>> >> >(For more details, refer https://github.com/riscv/riscv-aia)
>> >> >
>> >> >In APLIC MSI-mode, wired interrupts are forwared as message signaled
>> >> >interrupts (MSIs) to CPUs via IMSIC.
>> >> >
>> >> >We extend the existing APLIC irqchip driver to support MSI-mode for
>> >> >RISC-V platforms having both wired interrupts and MSIs.
>> >> >
>> >> >Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
>> >> >---
>> >> > drivers/irqchip/Kconfig | 6 +
>> >> > drivers/irqchip/Makefile | 1 +
>> >> > drivers/irqchip/irq-riscv-aplic-main.c | 2 +-
>> >> > drivers/irqchip/irq-riscv-aplic-main.h | 8 +
>> >> > drivers/irqchip/irq-riscv-aplic-msi.c | 285 +++++++++++++++++++++++++
>> >> > 5 files changed, 301 insertions(+), 1 deletion(-)
>> >> > create mode 100644 drivers/irqchip/irq-riscv-aplic-msi.c
>> >> >
>> >> >diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
>> >> >index 1996cc6f666a..7adc4dbe07ff 100644
>> >> >--- a/drivers/irqchip/Kconfig
>> >> >+++ b/drivers/irqchip/Kconfig
>> >> >@@ -551,6 +551,12 @@ config RISCV_APLIC
>> >> > depends on RISCV
>> >> > select IRQ_DOMAIN_HIERARCHY
>> >> >
>> >> >+config RISCV_APLIC_MSI
>> >> >+ bool
>> >> >+ depends on RISCV_APLIC
>> >> >+ select GENERIC_MSI_IRQ
>> >> >+ default RISCV_APLIC
>> >> >+
>> >> > config RISCV_IMSIC
>> >> > bool
>> >> > depends on RISCV
>> >> >diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
>> >> >index 7f8289790ed8..47995fdb2c60 100644
>> >> >--- a/drivers/irqchip/Makefile
>> >> >+++ b/drivers/irqchip/Makefile
>> >> >@@ -96,6 +96,7 @@ 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-main.o irq-riscv-aplic-direct.o
>> >> >+obj-$(CONFIG_RISCV_APLIC_MSI) += irq-riscv-aplic-msi.o
>> >> > obj-$(CONFIG_RISCV_IMSIC) += irq-riscv-imsic-state.o irq-riscv-imsic-early.o irq-riscv-imsic-platform.o
>> >> > obj-$(CONFIG_SIFIVE_PLIC) += irq-sifive-plic.o
>> >> > obj-$(CONFIG_IMX_IRQSTEER) += irq-imx-irqsteer.o
>> >> >diff --git a/drivers/irqchip/irq-riscv-aplic-main.c b/drivers/irqchip/irq-riscv-aplic-main.c
>> >> >index 87450708a733..d1b342b66551 100644
>> >> >--- a/drivers/irqchip/irq-riscv-aplic-main.c
>> >> >+++ b/drivers/irqchip/irq-riscv-aplic-main.c
>> >> >@@ -205,7 +205,7 @@ static int aplic_probe(struct platform_device *pdev)
>> >> > msi_mode = of_property_present(to_of_node(dev->fwnode),
>> >> > "msi-parent");
>> >> > if (msi_mode)
>> >> >- rc = -ENODEV;
>> >> >+ rc = aplic_msi_setup(dev, regs);
>> >> > else
>> >> > rc = aplic_direct_setup(dev, regs);
>> >> > if (rc) {
>> >> >diff --git a/drivers/irqchip/irq-riscv-aplic-main.h b/drivers/irqchip/irq-riscv-aplic-main.h
>> >> >index 474a04229334..78267ec58098 100644
>> >> >--- a/drivers/irqchip/irq-riscv-aplic-main.h
>> >> >+++ b/drivers/irqchip/irq-riscv-aplic-main.h
>> >> >@@ -41,5 +41,13 @@ void aplic_init_hw_global(struct aplic_priv *priv, bool msi_mode);
>> >> > int aplic_setup_priv(struct aplic_priv *priv, struct device *dev,
>> >> > void __iomem *regs);
>> >> > int aplic_direct_setup(struct device *dev, void __iomem *regs);
>> >> >+#ifdef CONFIG_RISCV_APLIC_MSI
>> >> >+int aplic_msi_setup(struct device *dev, void __iomem *regs);
>> >> >+#else
>> >> >+static inline int aplic_msi_setup(struct device *dev, void __iomem *regs)
>> >> >+{
>> >> >+ return -ENODEV;
>> >> >+}
>> >> >+#endif
>> >> >
>> >> > #endif
>> >> >diff --git a/drivers/irqchip/irq-riscv-aplic-msi.c b/drivers/irqchip/irq-riscv-aplic-msi.c
>> >> >new file mode 100644
>> >> >index 000000000000..086d00e0429e
>> >> >--- /dev/null
>> >> >+++ b/drivers/irqchip/irq-riscv-aplic-msi.c
>> >> >@@ -0,0 +1,285 @@
>> >> >+// SPDX-License-Identifier: GPL-2.0
>> >> >+/*
>> >> >+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
>> >> >+ * Copyright (C) 2022 Ventana Micro Systems Inc.
>> >> >+ */
>> >> >+
>> >> >+#include <linux/bitops.h>
>> >> >+#include <linux/cpu.h>
>> >> >+#include <linux/interrupt.h>
>> >> >+#include <linux/irqchip.h>
>> >> >+#include <linux/irqchip/riscv-aplic.h>
>> >> >+#include <linux/irqchip/riscv-imsic.h>
>> >> >+#include <linux/module.h>
>> >> >+#include <linux/msi.h>
>> >> >+#include <linux/of_irq.h>
>> >> >+#include <linux/platform_device.h>
>> >> >+#include <linux/printk.h>
>> >> >+#include <linux/smp.h>
>> >> >+
>> >> >+#include "irq-riscv-aplic-main.h"
>> >> >+
>> >> >+static void aplic_msi_irq_unmask(struct irq_data *d)
>> >> >+{
>> >> >+ aplic_irq_unmask(d);
>> >> >+ irq_chip_unmask_parent(d);
>> >> >+}
>> >> >+
>> >> >+static void aplic_msi_irq_mask(struct irq_data *d)
>> >> >+{
>> >> >+ aplic_irq_mask(d);
>> >> >+ irq_chip_mask_parent(d);
>> >> >+}
>> >> >+
>> >> >+static void aplic_msi_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.
>> >> >+ */
>> >> >+
>> >> >+ 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;
>> >> >+ }
>> >> >+}
>> >> >+
>> >> >+static struct irq_chip aplic_msi_chip = {
>> >> >+ .name = "APLIC-MSI",
>> >> >+ .irq_mask = aplic_msi_irq_mask,
>> >> >+ .irq_unmask = aplic_msi_irq_unmask,
>> >> >+ .irq_set_type = aplic_irq_set_type,
>> >> >+ .irq_eoi = aplic_msi_irq_eoi,
>> >> >+#ifdef CONFIG_SMP
>> >> >+ .irq_set_affinity = irq_chip_set_affinity_parent,
>> >> >+#endif
>> >> >+ .flags = IRQCHIP_SET_TYPE_MASKED |
>> >> >+ IRQCHIP_SKIP_SET_WAKE |
>> >> >+ IRQCHIP_MASK_ON_SUSPEND,
>> >> >+};
>> >> >+
>> >> >+static int aplic_msi_irqdomain_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_msi_irqdomain_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;
>> >>
>> >> In your patchset, the wired IRQ and IRQ of platform device will go into APLIC-MSI domain firstly.
>> >
>> >Yes, that is correct. In general, this applies to AIA specification
>> >and nothing to do with this patchset.
>> >
>> >> Let me assume here is a MSI IRQ not wired IRQ on a device, and it is a platform device in system.
>> >> so in aplic_irqdomain_translate() function, it will parse the APLIC physical IRQ number by fwspec->param[0],
>> >> but this is not a wried IRQ, it is a MSI IRQ, it should not has a APLIC physical IRQ number, the hwirq number should be allocated by MSI bitmap,
>> >> what value will be parse by DTS? zero or negative?
>> >
>> >For platform devices with MSI support, the MSIs will directly target
>> >the per-HART
>> >IMSICs and the DT node of such devices will never point to APLIC as the parent
>> >MSI controller.
>> >
>>
>> >The IMSIC driver implements the IMSIC-PLAT domain for platform MSIs.
>>
>> Have you test this case on QEMU? would you like share the test steps?
>
>The APLIC in MSI-mode acts like a platform device with MSIs so yes this
>is tested on QEMU.
yet, I know the wired interrupt with MSI-mode of APLIC has tested on QEMU by virtio devices, but i want to know how about the MSI interrupt with non-PCI device?
have you tested this case?