Re:Re: [PATCH v11 12/14] irqchip/riscv-aplic: Add support for MSI-mode

From: Ben  <figure1802@126.com>
To: "Anup Patel" <apatel@ventanamicro.com>
Cc: "Palmer Dabbelt" <palmer@dabbelt.com>,
	"Paul Walmsley" <paul.walmsley@sifive.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
	"Frank Rowand" <frowand.list@gmail.com>,
	"Conor Dooley" <conor+dt@kernel.org>,
	devicetree@vger.kernel.org,
	"Saravana Kannan" <saravanak@google.com>,
	"Marc Zyngier" <maz@kernel.org>,
	"Anup Patel" <anup@brainfault.org>,
	linux-kernel@vger.kernel.org, "Björn Töpel" <bjorn@kernel.org>,
	"Atish Patra" <atishp@atishpatra.org>,
	linux-riscv@lists.infradead.org,
	"Andrew Jones" <ajones@ventanamicro.com>
Subject: Re:Re: [PATCH v11 12/14] irqchip/riscv-aplic: Add support for MSI-mode
Date: Wed, 8 Nov 2023 22:51:38 +0800 (CST)	[thread overview]
Message-ID: <8624cc4.5923.18baf6adca4.Coremail.figure1802@126.com> (raw)
In-Reply-To: <CAK9=C2WPhROWKGKmLbLyS+q2ncCNTJEHnFKcYqCGJoNK4Uz=LQ@mail.gmail.com>

At 2023-11-08 22:43:25, "Anup Patel" <apatel@ventanamicro.com> wrote:
>On Sat, Nov 4, 2023 at 6:30 AM Ben <figure1802@126.com> wrote:
>>
>> At 2023-10-24 01:27:58, "Anup Patel" <apatel@ventanamicro.com> 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@ventanamicro.com>
>> >---
>> > 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?
_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv