[PATCH v5 2/7] iommu/riscv: Add RISC-V IOMMU platform device driver

Anup Patel apatel at ventanamicro.com
Fri May 17 20:51:15 PDT 2024


On Sat, May 18, 2024 at 1:11 AM Tomasz Jeznach <tjeznach at rivosinc.com> wrote:
>
> On Fri, May 17, 2024 at 9:28 AM Anup Patel <apatel at ventanamicro.com> wrote:
> >
> > Hi Tomasz,
> >
> > On Fri, May 17, 2024 at 9:16 PM Tomasz Jeznach <tjeznach at rivosinc.com> wrote:
> > >
> > > On Fri, May 17, 2024 at 12:22 AM Zong Li <zong.li at sifive.com> wrote:
> > > >
> > > > On Wed, May 15, 2024 at 2:17 AM Tomasz Jeznach <tjeznach at rivosinc.com> wrote:
> > > > >
> > > > > Introduce platform device driver for implementation of RISC-V IOMMU
> > > > > architected hardware.
> > > > >
> > > > > Hardware interface definition located in file iommu-bits.h is based on
> > > > > ratified RISC-V IOMMU Architecture Specification version 1.0.0.
> > > > >
> > > > > This patch implements platform device initialization, early check and
> > > > > configuration of the IOMMU interfaces and enables global pass-through
> > > > > address translation mode (iommu_mode == BARE), without registering
> > > > > hardware instance in the IOMMU subsystem.
> > > > >
> > > > > Link: https://github.com/riscv-non-isa/riscv-iommu
> > > > > Co-developed-by: Nick Kossifidis <mick at ics.forth.gr>
> > > > > Signed-off-by: Nick Kossifidis <mick at ics.forth.gr>
> > > > > Co-developed-by: Sebastien Boeuf <seb at rivosinc.com>
> > > > > Signed-off-by: Sebastien Boeuf <seb at rivosinc.com>
> > > > > Reviewed-by: Lu Baolu <baolu.lu at linux.intel.com>
> > > > > Signed-off-by: Tomasz Jeznach <tjeznach at rivosinc.com>
> > > > > ---
> > > > >  MAINTAINERS                          |   1 +
> > > > >  drivers/iommu/Kconfig                |   1 +
> > > > >  drivers/iommu/Makefile               |   2 +-
> > > > >  drivers/iommu/riscv/Kconfig          |  15 +
> > > > >  drivers/iommu/riscv/Makefile         |   2 +
> > > > >  drivers/iommu/riscv/iommu-bits.h     | 707 +++++++++++++++++++++++++++
> > > > >  drivers/iommu/riscv/iommu-platform.c |  92 ++++
> > > > >  drivers/iommu/riscv/iommu.c          |  99 ++++
> > > > >  drivers/iommu/riscv/iommu.h          |  62 +++
> > > > >  9 files changed, 980 insertions(+), 1 deletion(-)
> > > > >  create mode 100644 drivers/iommu/riscv/Kconfig
> > > > >  create mode 100644 drivers/iommu/riscv/Makefile
> > > > >  create mode 100644 drivers/iommu/riscv/iommu-bits.h
> > > > >  create mode 100644 drivers/iommu/riscv/iommu-platform.c
> > > > >  create mode 100644 drivers/iommu/riscv/iommu.c
> > > > >  create mode 100644 drivers/iommu/riscv/iommu.h
> > > > >
> > > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > > index 7e090f878dc7..c0ef07031d01 100644
> > > > > --- a/MAINTAINERS
> > > > > +++ b/MAINTAINERS
> > > > > @@ -18963,6 +18963,7 @@ L:      iommu at lists.linux.dev
> > > > >  L:     linux-riscv at lists.infradead.org
> > > > >  S:     Maintained
> > > > >  F:     Documentation/devicetree/bindings/iommu/riscv,iommu.yaml
> > > > > +F:     drivers/iommu/riscv/
> > > > >
> > > > >  RISC-V MICROCHIP FPGA SUPPORT
> > > > >  M:     Conor Dooley <conor.dooley at microchip.com>
> > > > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> > > > > index c04584be3089..9359f07fe671 100644
> > > > > --- a/drivers/iommu/Kconfig
> > > > > +++ b/drivers/iommu/Kconfig
> > > > > @@ -195,6 +195,7 @@ config MSM_IOMMU
> > > > >  source "drivers/iommu/amd/Kconfig"
> > > > >  source "drivers/iommu/intel/Kconfig"
> > > > >  source "drivers/iommu/iommufd/Kconfig"
> > > > > +source "drivers/iommu/riscv/Kconfig"
> > > > >
> > > > >  config IRQ_REMAP
> > > > >         bool "Support for Interrupt Remapping"
> > > > > diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
> > > > > index 542760d963ec..5e5a83c6c2aa 100644
> > > > > --- a/drivers/iommu/Makefile
> > > > > +++ b/drivers/iommu/Makefile
> > > > > @@ -1,5 +1,5 @@
> > > > >  # SPDX-License-Identifier: GPL-2.0
> > > > > -obj-y += amd/ intel/ arm/ iommufd/
> > > > > +obj-y += amd/ intel/ arm/ iommufd/ riscv/
> > > > >  obj-$(CONFIG_IOMMU_API) += iommu.o
> > > > >  obj-$(CONFIG_IOMMU_API) += iommu-traces.o
> > > > >  obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
> > > > > diff --git a/drivers/iommu/riscv/Kconfig b/drivers/iommu/riscv/Kconfig
> > > > > new file mode 100644
> > > > > index 000000000000..5dcc5c45aa50
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/Kconfig
> > > > > @@ -0,0 +1,15 @@
> > > > > +# SPDX-License-Identifier: GPL-2.0-only
> > > > > +# RISC-V IOMMU support
> > > > > +
> > > > > +config RISCV_IOMMU
> > > > > +       bool "RISC-V IOMMU Support"
> > > > > +       depends on RISCV && 64BIT
> > > > > +       default y
> > > > > +       select IOMMU_API
> > > >
> > > > Hi Tomasz,
> > > > Could I know do we need to add RISCV dependency on CONFIG_IOMMU_DMA
> > > > due to the patch 'de9f8a91eb32 ("iommu/dma: Clean up Kconfig")'?
> > > >
> > >
> > > Hi Zong,
> > >
> > > Correct, This series will be followed with actual enablement of the
> > > iommu/riscv driver with the change to add IOMMU_DMA for RISCV arch,
> > > here is the change:
> >
> > I understand that this series is intended to be minimal but I suggest
> > expanding this series a bit more such that at least a basic EDU device
> > works along with MSIs from EDU device. This will give us a more
> > usable IOMMU driver sooner and also allow people to do more
> > testing.
> >
> > Subsequent series can add more features (such as IOMMU_DMA,
> > HPM, etc) incrementally.
> >
>
> Hi Anup,
>
> This series introduces a fundamental and practical IOMMU/RISC-V
> driver. It is fully testable on simulated, emulated, or real hardware
> implementations of the RISC-V architecture. Users can enable
> additional kernel configuration options, such as VFIO and IOMMU_DMA,
> to facilitate testing.

In terms of features, what is fundamental and practical IOMMU
driver to you might not be for others.

>
> The activation of IOMMU_DMA for the RISC-V architecture will be
> feasible once the core components achieve compatibility with the DMA
> subsystem, which unfortunately is currently not the case. Without
> IOMMU_DMA enabled, driver will recognize RISC-V IOMMU hardware,
> register itself in the IOMMU core subsystem, and will provide basic
> IDENTITY protection domains for connected devices.

I am not asking for IOMMU_DMA feature instead I am asking for
supporting device MSIs in this series.

>
> For those interested in testing this series (based on v6.9), with MSI
> support (riscv_aia_v17), I have provided a ready to use branch [1]
> with necessary fixes/workarounds included for convenience.
>
> [1] link: https://github.com/tjeznach/linux/tree/riscv_iommu_v5_aia_17

Up-streaming the patches is much more useful compared to
sharing patches in private branches.

It seems you already have subsequent patches so why not just
submit another series which depends on this series ?

It is very easy to pull patches from mailing list using b4. Waiting
for this series to be merged before sending another series will
only delay having a usable driver in upstream. People send-out
multiple interdependent series all the time. Usually, it takes time
to review patches so it is generally better to have patches on the
list as soon as possible. This also allows others to test and
propose or send fixes on top.

Regards,
Anup

>
> Best regards,
> - Tomasz
>
>
> > Regards,
> > Anup
> >
> > >
> > > --- a/drivers/iommu/Kconfig
> > > +++ b/drivers/iommu/Kconfig
> > > @@ -150,7 +150,7 @@ config OF_IOMMU
> > >
> > >  # IOMMU-agnostic DMA-mapping layer
> > >  config IOMMU_DMA
> > > -       def_bool ARM64 || X86 || S390
> > > +       def_bool ARM64 || X86 || S390 || RISCV
> > >         select DMA_OPS
> > >         select IOMMU_API
> > >         select IOMMU_IOVA
> > >
> > > Best regards,
> > > - Tomasz
> > >
> > > > > +       help
> > > > > +         Support for implementations of the RISC-V IOMMU architecture that
> > > > > +         complements the RISC-V MMU capabilities, providing similar address
> > > > > +         translation and protection functions for accesses from I/O devices.
> > > > > +
> > > > > +         Say Y here if your SoC includes an IOMMU device implementing
> > > > > +         the RISC-V IOMMU architecture.
> > > > > diff --git a/drivers/iommu/riscv/Makefile b/drivers/iommu/riscv/Makefile
> > > > > new file mode 100644
> > > > > index 000000000000..e4c189de58d3
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/Makefile
> > > > > @@ -0,0 +1,2 @@
> > > > > +# SPDX-License-Identifier: GPL-2.0-only
> > > > > +obj-$(CONFIG_RISCV_IOMMU) += iommu.o iommu-platform.o
> > > > > diff --git a/drivers/iommu/riscv/iommu-bits.h b/drivers/iommu/riscv/iommu-bits.h
> > > > > new file mode 100644
> > > > > index 000000000000..48f795a0cd10
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/iommu-bits.h
> > > > > @@ -0,0 +1,707 @@
> > > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > > +/*
> > > > > + * Copyright © 2022-2024 Rivos Inc.
> > > > > + * Copyright © 2023 FORTH-ICS/CARV
> > > > > + * Copyright © 2023 RISC-V IOMMU Task Group
> > > > > + *
> > > > > + * RISC-V IOMMU - Register Layout and Data Structures.
> > > > > + *
> > > > > + * Based on the 'RISC-V IOMMU Architecture Specification', Version 1.0
> > > > > + * Published at  https://github.com/riscv-non-isa/riscv-iommu
> > > > > + *
> > > > > + */
> > > > > +
> > > > > +#ifndef _RISCV_IOMMU_BITS_H_
> > > > > +#define _RISCV_IOMMU_BITS_H_
> > > > > +
> > > > > +#include <linux/types.h>
> > > > > +#include <linux/bitfield.h>
> > > > > +#include <linux/bits.h>
> > > > > +
> > > > > +/*
> > > > > + * Chapter 5: Memory Mapped register interface
> > > > > + */
> > > > > +
> > > > > +/* Common field positions */
> > > > > +#define RISCV_IOMMU_PPN_FIELD          GENMASK_ULL(53, 10)
> > > > > +#define RISCV_IOMMU_QUEUE_LOGSZ_FIELD  GENMASK_ULL(4, 0)
> > > > > +#define RISCV_IOMMU_QUEUE_INDEX_FIELD  GENMASK_ULL(31, 0)
> > > > > +#define RISCV_IOMMU_QUEUE_ENABLE       BIT(0)
> > > > > +#define RISCV_IOMMU_QUEUE_INTR_ENABLE  BIT(1)
> > > > > +#define RISCV_IOMMU_QUEUE_MEM_FAULT    BIT(8)
> > > > > +#define RISCV_IOMMU_QUEUE_OVERFLOW     BIT(9)
> > > > > +#define RISCV_IOMMU_QUEUE_ACTIVE       BIT(16)
> > > > > +#define RISCV_IOMMU_QUEUE_BUSY         BIT(17)
> > > > > +
> > > > > +#define RISCV_IOMMU_ATP_PPN_FIELD      GENMASK_ULL(43, 0)
> > > > > +#define RISCV_IOMMU_ATP_MODE_FIELD     GENMASK_ULL(63, 60)
> > > > > +
> > > > > +/* 5.3 IOMMU Capabilities (64bits) */
> > > > > +#define RISCV_IOMMU_REG_CAP            0x0000
> > > > > +#define RISCV_IOMMU_CAP_VERSION                GENMASK_ULL(7, 0)
> > > > > +#define RISCV_IOMMU_CAP_S_SV32         BIT_ULL(8)
> > > > > +#define RISCV_IOMMU_CAP_S_SV39         BIT_ULL(9)
> > > > > +#define RISCV_IOMMU_CAP_S_SV48         BIT_ULL(10)
> > > > > +#define RISCV_IOMMU_CAP_S_SV57         BIT_ULL(11)
> > > > > +#define RISCV_IOMMU_CAP_SVPBMT         BIT_ULL(15)
> > > > > +#define RISCV_IOMMU_CAP_G_SV32         BIT_ULL(16)
> > > > > +#define RISCV_IOMMU_CAP_G_SV39         BIT_ULL(17)
> > > > > +#define RISCV_IOMMU_CAP_G_SV48         BIT_ULL(18)
> > > > > +#define RISCV_IOMMU_CAP_G_SV57         BIT_ULL(19)
> > > > > +#define RISCV_IOMMU_CAP_AMO_MRIF       BIT_ULL(21)
> > > > > +#define RISCV_IOMMU_CAP_MSI_FLAT       BIT_ULL(22)
> > > > > +#define RISCV_IOMMU_CAP_MSI_MRIF       BIT_ULL(23)
> > > > > +#define RISCV_IOMMU_CAP_AMO_HWAD       BIT_ULL(24)
> > > > > +#define RISCV_IOMMU_CAP_ATS            BIT_ULL(25)
> > > > > +#define RISCV_IOMMU_CAP_T2GPA          BIT_ULL(26)
> > > > > +#define RISCV_IOMMU_CAP_END            BIT_ULL(27)
> > > > > +#define RISCV_IOMMU_CAP_IGS            GENMASK_ULL(29, 28)
> > > > > +#define RISCV_IOMMU_CAP_HPM            BIT_ULL(30)
> > > > > +#define RISCV_IOMMU_CAP_DBG            BIT_ULL(31)
> > > > > +#define RISCV_IOMMU_CAP_PAS            GENMASK_ULL(37, 32)
> > > > > +#define RISCV_IOMMU_CAP_PD8            BIT_ULL(38)
> > > > > +#define RISCV_IOMMU_CAP_PD17           BIT_ULL(39)
> > > > > +#define RISCV_IOMMU_CAP_PD20           BIT_ULL(40)
> > > > > +
> > > > > +#define RISCV_IOMMU_CAP_VERSION_VER_MASK       0xF0
> > > > > +#define RISCV_IOMMU_CAP_VERSION_REV_MASK       0x0F
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_igs_settings - Interrupt Generation Support Settings
> > > > > + * @RISCV_IOMMU_CAP_IGS_MSI: I/O MMU supports only MSI generation
> > > > > + * @RISCV_IOMMU_CAP_IGS_WSI: I/O MMU supports only Wired-Signaled interrupt
> > > > > + * @RISCV_IOMMU_CAP_IGS_BOTH: I/O MMU supports both MSI and WSI generation
> > > > > + * @RISCV_IOMMU_CAP_IGS_RSRV: Reserved for standard use
> > > > > + */
> > > > > +enum riscv_iommu_igs_settings {
> > > > > +       RISCV_IOMMU_CAP_IGS_MSI = 0,
> > > > > +       RISCV_IOMMU_CAP_IGS_WSI = 1,
> > > > > +       RISCV_IOMMU_CAP_IGS_BOTH = 2,
> > > > > +       RISCV_IOMMU_CAP_IGS_RSRV = 3
> > > > > +};
> > > > > +
> > > > > +/* 5.4 Features control register (32bits) */
> > > > > +#define RISCV_IOMMU_REG_FCTL           0x0008
> > > > > +#define RISCV_IOMMU_FCTL_BE            BIT(0)
> > > > > +#define RISCV_IOMMU_FCTL_WSI           BIT(1)
> > > > > +#define RISCV_IOMMU_FCTL_GXL           BIT(2)
> > > > > +
> > > > > +/* 5.5 Device-directory-table pointer (64bits) */
> > > > > +#define RISCV_IOMMU_REG_DDTP           0x0010
> > > > > +#define RISCV_IOMMU_DDTP_MODE          GENMASK_ULL(3, 0)
> > > > > +#define RISCV_IOMMU_DDTP_BUSY          BIT_ULL(4)
> > > > > +#define RISCV_IOMMU_DDTP_PPN           RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_ddtp_modes - I/O MMU translation modes
> > > > > + * @RISCV_IOMMU_DDTP_MODE_OFF: No inbound transactions allowed
> > > > > + * @RISCV_IOMMU_DDTP_MODE_BARE: Pass-through mode
> > > > > + * @RISCV_IOMMU_DDTP_MODE_1LVL: One-level DDT
> > > > > + * @RISCV_IOMMU_DDTP_MODE_2LVL: Two-level DDT
> > > > > + * @RISCV_IOMMU_DDTP_MODE_3LVL: Three-level DDT
> > > > > + * @RISCV_IOMMU_DDTP_MODE_MAX: Max value allowed by specification
> > > > > + */
> > > > > +enum riscv_iommu_ddtp_modes {
> > > > > +       RISCV_IOMMU_DDTP_MODE_OFF = 0,
> > > > > +       RISCV_IOMMU_DDTP_MODE_BARE = 1,
> > > > > +       RISCV_IOMMU_DDTP_MODE_1LVL = 2,
> > > > > +       RISCV_IOMMU_DDTP_MODE_2LVL = 3,
> > > > > +       RISCV_IOMMU_DDTP_MODE_3LVL = 4,
> > > > > +       RISCV_IOMMU_DDTP_MODE_MAX = 4
> > > > > +};
> > > > > +
> > > > > +/* 5.6 Command Queue Base (64bits) */
> > > > > +#define RISCV_IOMMU_REG_CQB            0x0018
> > > > > +#define RISCV_IOMMU_CQB_ENTRIES                RISCV_IOMMU_QUEUE_LOGSZ_FIELD
> > > > > +#define RISCV_IOMMU_CQB_PPN            RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/* 5.7 Command Queue head (32bits) */
> > > > > +#define RISCV_IOMMU_REG_CQH            0x0020
> > > > > +#define RISCV_IOMMU_CQH_INDEX          RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.8 Command Queue tail (32bits) */
> > > > > +#define RISCV_IOMMU_REG_CQT            0x0024
> > > > > +#define RISCV_IOMMU_CQT_INDEX          RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.9 Fault Queue Base (64bits) */
> > > > > +#define RISCV_IOMMU_REG_FQB            0x0028
> > > > > +#define RISCV_IOMMU_FQB_ENTRIES                RISCV_IOMMU_QUEUE_LOGSZ_FIELD
> > > > > +#define RISCV_IOMMU_FQB_PPN            RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/* 5.10 Fault Queue Head (32bits) */
> > > > > +#define RISCV_IOMMU_REG_FQH            0x0030
> > > > > +#define RISCV_IOMMU_FQH_INDEX          RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.11 Fault Queue tail (32bits) */
> > > > > +#define RISCV_IOMMU_REG_FQT            0x0034
> > > > > +#define RISCV_IOMMU_FQT_INDEX          RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.12 Page Request Queue base (64bits) */
> > > > > +#define RISCV_IOMMU_REG_PQB            0x0038
> > > > > +#define RISCV_IOMMU_PQB_ENTRIES                RISCV_IOMMU_QUEUE_LOGSZ_FIELD
> > > > > +#define RISCV_IOMMU_PQB_PPN            RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/* 5.13 Page Request Queue head (32bits) */
> > > > > +#define RISCV_IOMMU_REG_PQH            0x0040
> > > > > +#define RISCV_IOMMU_PQH_INDEX          RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.14 Page Request Queue tail (32bits) */
> > > > > +#define RISCV_IOMMU_REG_PQT            0x0044
> > > > > +#define RISCV_IOMMU_PQT_INDEX_MASK     RISCV_IOMMU_QUEUE_INDEX_FIELD
> > > > > +
> > > > > +/* 5.15 Command Queue CSR (32bits) */
> > > > > +#define RISCV_IOMMU_REG_CQCSR          0x0048
> > > > > +#define RISCV_IOMMU_CQCSR_CQEN         RISCV_IOMMU_QUEUE_ENABLE
> > > > > +#define RISCV_IOMMU_CQCSR_CIE          RISCV_IOMMU_QUEUE_INTR_ENABLE
> > > > > +#define RISCV_IOMMU_CQCSR_CQMF         RISCV_IOMMU_QUEUE_MEM_FAULT
> > > > > +#define RISCV_IOMMU_CQCSR_CMD_TO       BIT(9)
> > > > > +#define RISCV_IOMMU_CQCSR_CMD_ILL      BIT(10)
> > > > > +#define RISCV_IOMMU_CQCSR_FENCE_W_IP   BIT(11)
> > > > > +#define RISCV_IOMMU_CQCSR_CQON         RISCV_IOMMU_QUEUE_ACTIVE
> > > > > +#define RISCV_IOMMU_CQCSR_BUSY         RISCV_IOMMU_QUEUE_BUSY
> > > > > +
> > > > > +/* 5.16 Fault Queue CSR (32bits) */
> > > > > +#define RISCV_IOMMU_REG_FQCSR          0x004C
> > > > > +#define RISCV_IOMMU_FQCSR_FQEN         RISCV_IOMMU_QUEUE_ENABLE
> > > > > +#define RISCV_IOMMU_FQCSR_FIE          RISCV_IOMMU_QUEUE_INTR_ENABLE
> > > > > +#define RISCV_IOMMU_FQCSR_FQMF         RISCV_IOMMU_QUEUE_MEM_FAULT
> > > > > +#define RISCV_IOMMU_FQCSR_FQOF         RISCV_IOMMU_QUEUE_OVERFLOW
> > > > > +#define RISCV_IOMMU_FQCSR_FQON         RISCV_IOMMU_QUEUE_ACTIVE
> > > > > +#define RISCV_IOMMU_FQCSR_BUSY         RISCV_IOMMU_QUEUE_BUSY
> > > > > +
> > > > > +/* 5.17 Page Request Queue CSR (32bits) */
> > > > > +#define RISCV_IOMMU_REG_PQCSR          0x0050
> > > > > +#define RISCV_IOMMU_PQCSR_PQEN         RISCV_IOMMU_QUEUE_ENABLE
> > > > > +#define RISCV_IOMMU_PQCSR_PIE          RISCV_IOMMU_QUEUE_INTR_ENABLE
> > > > > +#define RISCV_IOMMU_PQCSR_PQMF         RISCV_IOMMU_QUEUE_MEM_FAULT
> > > > > +#define RISCV_IOMMU_PQCSR_PQOF         RISCV_IOMMU_QUEUE_OVERFLOW
> > > > > +#define RISCV_IOMMU_PQCSR_PQON         RISCV_IOMMU_QUEUE_ACTIVE
> > > > > +#define RISCV_IOMMU_PQCSR_BUSY         RISCV_IOMMU_QUEUE_BUSY
> > > > > +
> > > > > +/* 5.18 Interrupt Pending Status (32bits) */
> > > > > +#define RISCV_IOMMU_REG_IPSR           0x0054
> > > > > +
> > > > > +#define RISCV_IOMMU_INTR_CQ            0
> > > > > +#define RISCV_IOMMU_INTR_FQ            1
> > > > > +#define RISCV_IOMMU_INTR_PM            2
> > > > > +#define RISCV_IOMMU_INTR_PQ            3
> > > > > +#define RISCV_IOMMU_INTR_COUNT         4
> > > > > +
> > > > > +#define RISCV_IOMMU_IPSR_CIP           BIT(RISCV_IOMMU_INTR_CQ)
> > > > > +#define RISCV_IOMMU_IPSR_FIP           BIT(RISCV_IOMMU_INTR_FQ)
> > > > > +#define RISCV_IOMMU_IPSR_PMIP          BIT(RISCV_IOMMU_INTR_PM)
> > > > > +#define RISCV_IOMMU_IPSR_PIP           BIT(RISCV_IOMMU_INTR_PQ)
> > > > > +
> > > > > +/* 5.19 Performance monitoring counter overflow status (32bits) */
> > > > > +#define RISCV_IOMMU_REG_IOCOUNTOVF     0x0058
> > > > > +#define RISCV_IOMMU_IOCOUNTOVF_CY      BIT(0)
> > > > > +#define RISCV_IOMMU_IOCOUNTOVF_HPM     GENMASK_ULL(31, 1)
> > > > > +
> > > > > +/* 5.20 Performance monitoring counter inhibits (32bits) */
> > > > > +#define RISCV_IOMMU_REG_IOCOUNTINH     0x005C
> > > > > +#define RISCV_IOMMU_IOCOUNTINH_CY      BIT(0)
> > > > > +#define RISCV_IOMMU_IOCOUNTINH_HPM     GENMASK(31, 1)
> > > > > +
> > > > > +/* 5.21 Performance monitoring cycles counter (64bits) */
> > > > > +#define RISCV_IOMMU_REG_IOHPMCYCLES     0x0060
> > > > > +#define RISCV_IOMMU_IOHPMCYCLES_COUNTER        GENMASK_ULL(62, 0)
> > > > > +#define RISCV_IOMMU_IOHPMCYCLES_OVF    BIT_ULL(63)
> > > > > +
> > > > > +/* 5.22 Performance monitoring event counters (31 * 64bits) */
> > > > > +#define RISCV_IOMMU_REG_IOHPMCTR_BASE  0x0068
> > > > > +#define RISCV_IOMMU_REG_IOHPMCTR(_n)   (RISCV_IOMMU_REG_IOHPMCTR_BASE + ((_n) * 0x8))
> > > > > +
> > > > > +/* 5.23 Performance monitoring event selectors (31 * 64bits) */
> > > > > +#define RISCV_IOMMU_REG_IOHPMEVT_BASE  0x0160
> > > > > +#define RISCV_IOMMU_REG_IOHPMEVT(_n)   (RISCV_IOMMU_REG_IOHPMEVT_BASE + ((_n) * 0x8))
> > > > > +#define RISCV_IOMMU_IOHPMEVT_CNT       31
> > > > > +#define RISCV_IOMMU_IOHPMEVT_EVENT_ID  GENMASK_ULL(14, 0)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_DMASK     BIT_ULL(15)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_PID_PSCID GENMASK_ULL(35, 16)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_DID_GSCID GENMASK_ULL(59, 36)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_PV_PSCV   BIT_ULL(60)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_DV_GSCV   BIT_ULL(61)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_IDT       BIT_ULL(62)
> > > > > +#define RISCV_IOMMU_IOHPMEVT_OF                BIT_ULL(63)
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_hpmevent_id - Performance-monitoring event identifier
> > > > > + *
> > > > > + * @RISCV_IOMMU_HPMEVENT_INVALID: Invalid event, do not count
> > > > > + * @RISCV_IOMMU_HPMEVENT_URQ: Untranslated requests
> > > > > + * @RISCV_IOMMU_HPMEVENT_TRQ: Translated requests
> > > > > + * @RISCV_IOMMU_HPMEVENT_ATS_RQ: ATS translation requests
> > > > > + * @RISCV_IOMMU_HPMEVENT_TLB_MISS: TLB misses
> > > > > + * @RISCV_IOMMU_HPMEVENT_DD_WALK: Device directory walks
> > > > > + * @RISCV_IOMMU_HPMEVENT_PD_WALK: Process directory walks
> > > > > + * @RISCV_IOMMU_HPMEVENT_S_VS_WALKS: S/VS-Stage page table walks
> > > > > + * @RISCV_IOMMU_HPMEVENT_G_WALKS: G-Stage page table walks
> > > > > + * @RISCV_IOMMU_HPMEVENT_MAX: Value to denote maximum Event IDs
> > > > > + */
> > > > > +enum riscv_iommu_hpmevent_id {
> > > > > +       RISCV_IOMMU_HPMEVENT_INVALID    = 0,
> > > > > +       RISCV_IOMMU_HPMEVENT_URQ        = 1,
> > > > > +       RISCV_IOMMU_HPMEVENT_TRQ        = 2,
> > > > > +       RISCV_IOMMU_HPMEVENT_ATS_RQ     = 3,
> > > > > +       RISCV_IOMMU_HPMEVENT_TLB_MISS   = 4,
> > > > > +       RISCV_IOMMU_HPMEVENT_DD_WALK    = 5,
> > > > > +       RISCV_IOMMU_HPMEVENT_PD_WALK    = 6,
> > > > > +       RISCV_IOMMU_HPMEVENT_S_VS_WALKS = 7,
> > > > > +       RISCV_IOMMU_HPMEVENT_G_WALKS    = 8,
> > > > > +       RISCV_IOMMU_HPMEVENT_MAX        = 9
> > > > > +};
> > > > > +
> > > > > +/* 5.24 Translation request IOVA (64bits) */
> > > > > +#define RISCV_IOMMU_REG_TR_REQ_IOVA     0x0258
> > > > > +#define RISCV_IOMMU_TR_REQ_IOVA_VPN    GENMASK_ULL(63, 12)
> > > > > +
> > > > > +/* 5.25 Translation request control (64bits) */
> > > > > +#define RISCV_IOMMU_REG_TR_REQ_CTL     0x0260
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_GO_BUSY BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_PRIV    BIT_ULL(1)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_EXE     BIT_ULL(2)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_NW      BIT_ULL(3)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_PID     GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_PV      BIT_ULL(32)
> > > > > +#define RISCV_IOMMU_TR_REQ_CTL_DID     GENMASK_ULL(63, 40)
> > > > > +
> > > > > +/* 5.26 Translation request response (64bits) */
> > > > > +#define RISCV_IOMMU_REG_TR_RESPONSE    0x0268
> > > > > +#define RISCV_IOMMU_TR_RESPONSE_FAULT  BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_TR_RESPONSE_PBMT   GENMASK_ULL(8, 7)
> > > > > +#define RISCV_IOMMU_TR_RESPONSE_SZ     BIT_ULL(9)
> > > > > +#define RISCV_IOMMU_TR_RESPONSE_PPN    RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/* 5.27 Interrupt cause to vector (64bits) */
> > > > > +#define RISCV_IOMMU_REG_ICVEC          0x02F8
> > > > > +#define RISCV_IOMMU_ICVEC_CIV          GENMASK_ULL(3, 0)
> > > > > +#define RISCV_IOMMU_ICVEC_FIV          GENMASK_ULL(7, 4)
> > > > > +#define RISCV_IOMMU_ICVEC_PMIV         GENMASK_ULL(11, 8)
> > > > > +#define RISCV_IOMMU_ICVEC_PIV          GENMASK_ULL(15, 12)
> > > > > +
> > > > > +/* 5.28 MSI Configuration table (32 * 64bits) */
> > > > > +#define RISCV_IOMMU_REG_MSI_CONFIG     0x0300
> > > > > +#define RISCV_IOMMU_REG_MSI_ADDR(_n)   (RISCV_IOMMU_REG_MSI_CONFIG + ((_n) * 0x10))
> > > > > +#define RISCV_IOMMU_MSI_ADDR           GENMASK_ULL(55, 2)
> > > > > +#define RISCV_IOMMU_REG_MSI_DATA(_n)   (RISCV_IOMMU_REG_MSI_CONFIG + ((_n) * 0x10) + 0x08)
> > > > > +#define RISCV_IOMMU_MSI_DATA           GENMASK_ULL(31, 0)
> > > > > +#define RISCV_IOMMU_REG_MSI_VEC_CTL(_n)        (RISCV_IOMMU_REG_MSI_CONFIG + ((_n) * 0x10) + 0x0C)
> > > > > +#define RISCV_IOMMU_MSI_VEC_CTL_M      BIT_ULL(0)
> > > > > +
> > > > > +#define RISCV_IOMMU_REG_SIZE   0x1000
> > > > > +
> > > > > +/*
> > > > > + * Chapter 2: Data structures
> > > > > + */
> > > > > +
> > > > > +/*
> > > > > + * Device Directory Table macros for non-leaf nodes
> > > > > + */
> > > > > +#define RISCV_IOMMU_DDTE_VALID BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_DDTE_PPN   RISCV_IOMMU_PPN_FIELD
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_dc - Device Context
> > > > > + * @tc: Translation Control
> > > > > + * @iohgatp: I/O Hypervisor guest address translation and protection
> > > > > + *          (Second stage context)
> > > > > + * @ta: Translation Attributes
> > > > > + * @fsc: First stage context
> > > > > + * @msiptp: MSI page table pointer
> > > > > + * @msi_addr_mask: MSI address mask
> > > > > + * @msi_addr_pattern: MSI address pattern
> > > > > + * @_reserved: Reserved for future use, padding
> > > > > + *
> > > > > + * This structure is used for leaf nodes on the Device Directory Table,
> > > > > + * in case RISCV_IOMMU_CAP_MSI_FLAT is not set, the bottom 4 fields are
> > > > > + * not present and are skipped with pointer arithmetic to avoid
> > > > > + * casting, check out riscv_iommu_get_dc().
> > > > > + * See section 2.1 for more details
> > > > > + */
> > > > > +struct riscv_iommu_dc {
> > > > > +       u64 tc;
> > > > > +       u64 iohgatp;
> > > > > +       u64 ta;
> > > > > +       u64 fsc;
> > > > > +       u64 msiptp;
> > > > > +       u64 msi_addr_mask;
> > > > > +       u64 msi_addr_pattern;
> > > > > +       u64 _reserved;
> > > > > +};
> > > > > +
> > > > > +/* Translation control fields */
> > > > > +#define RISCV_IOMMU_DC_TC_V            BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_DC_TC_EN_ATS       BIT_ULL(1)
> > > > > +#define RISCV_IOMMU_DC_TC_EN_PRI       BIT_ULL(2)
> > > > > +#define RISCV_IOMMU_DC_TC_T2GPA                BIT_ULL(3)
> > > > > +#define RISCV_IOMMU_DC_TC_DTF          BIT_ULL(4)
> > > > > +#define RISCV_IOMMU_DC_TC_PDTV         BIT_ULL(5)
> > > > > +#define RISCV_IOMMU_DC_TC_PRPR         BIT_ULL(6)
> > > > > +#define RISCV_IOMMU_DC_TC_GADE         BIT_ULL(7)
> > > > > +#define RISCV_IOMMU_DC_TC_SADE         BIT_ULL(8)
> > > > > +#define RISCV_IOMMU_DC_TC_DPE          BIT_ULL(9)
> > > > > +#define RISCV_IOMMU_DC_TC_SBE          BIT_ULL(10)
> > > > > +#define RISCV_IOMMU_DC_TC_SXL          BIT_ULL(11)
> > > > > +
> > > > > +/* Second-stage (aka G-stage) context fields */
> > > > > +#define RISCV_IOMMU_DC_IOHGATP_PPN     RISCV_IOMMU_ATP_PPN_FIELD
> > > > > +#define RISCV_IOMMU_DC_IOHGATP_GSCID   GENMASK_ULL(59, 44)
> > > > > +#define RISCV_IOMMU_DC_IOHGATP_MODE    RISCV_IOMMU_ATP_MODE_FIELD
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_dc_iohgatp_modes - Guest address translation/protection modes
> > > > > + * @RISCV_IOMMU_DC_IOHGATP_MODE_BARE: No translation/protection
> > > > > + * @RISCV_IOMMU_DC_IOHGATP_MODE_SV32X4: Sv32x4 (2-bit extension of Sv32), when fctl.GXL == 1
> > > > > + * @RISCV_IOMMU_DC_IOHGATP_MODE_SV39X4: Sv39x4 (2-bit extension of Sv39), when fctl.GXL == 0
> > > > > + * @RISCV_IOMMU_DC_IOHGATP_MODE_SV48X4: Sv48x4 (2-bit extension of Sv48), when fctl.GXL == 0
> > > > > + * @RISCV_IOMMU_DC_IOHGATP_MODE_SV57X4: Sv57x4 (2-bit extension of Sv57), when fctl.GXL == 0
> > > > > + */
> > > > > +enum riscv_iommu_dc_iohgatp_modes {
> > > > > +       RISCV_IOMMU_DC_IOHGATP_MODE_BARE = 0,
> > > > > +       RISCV_IOMMU_DC_IOHGATP_MODE_SV32X4 = 8,
> > > > > +       RISCV_IOMMU_DC_IOHGATP_MODE_SV39X4 = 8,
> > > > > +       RISCV_IOMMU_DC_IOHGATP_MODE_SV48X4 = 9,
> > > > > +       RISCV_IOMMU_DC_IOHGATP_MODE_SV57X4 = 10
> > > > > +};
> > > > > +
> > > > > +/* Translation attributes fields */
> > > > > +#define RISCV_IOMMU_DC_TA_PSCID                GENMASK_ULL(31, 12)
> > > > > +
> > > > > +/* First-stage context fields */
> > > > > +#define RISCV_IOMMU_DC_FSC_PPN         RISCV_IOMMU_ATP_PPN_FIELD
> > > > > +#define RISCV_IOMMU_DC_FSC_MODE                RISCV_IOMMU_ATP_MODE_FIELD
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_dc_fsc_atp_modes - First stage address translation/protection modes
> > > > > + * @RISCV_IOMMU_DC_FSC_MODE_BARE: No translation/protection
> > > > > + * @RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV32: Sv32, when dc.tc.SXL == 1
> > > > > + * @RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV39: Sv39, when dc.tc.SXL == 0
> > > > > + * @RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV48: Sv48, when dc.tc.SXL == 0
> > > > > + * @RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV57: Sv57, when dc.tc.SXL == 0
> > > > > + * @RISCV_IOMMU_DC_FSC_PDTP_MODE_PD8: 1lvl PDT, 8bit process ids
> > > > > + * @RISCV_IOMMU_DC_FSC_PDTP_MODE_PD17: 2lvl PDT, 17bit process ids
> > > > > + * @RISCV_IOMMU_DC_FSC_PDTP_MODE_PD20: 3lvl PDT, 20bit process ids
> > > > > + *
> > > > > + * FSC holds IOSATP when RISCV_IOMMU_DC_TC_PDTV is 0 and PDTP otherwise.
> > > > > + * IOSATP controls the first stage address translation (same as the satp register on
> > > > > + * the RISC-V MMU), and PDTP holds the process directory table, used to select a
> > > > > + * first stage page table based on a process id (for devices that support multiple
> > > > > + * process ids).
> > > > > + */
> > > > > +enum riscv_iommu_dc_fsc_atp_modes {
> > > > > +       RISCV_IOMMU_DC_FSC_MODE_BARE = 0,
> > > > > +       RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV32 = 8,
> > > > > +       RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV39 = 8,
> > > > > +       RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV48 = 9,
> > > > > +       RISCV_IOMMU_DC_FSC_IOSATP_MODE_SV57 = 10,
> > > > > +       RISCV_IOMMU_DC_FSC_PDTP_MODE_PD8 = 1,
> > > > > +       RISCV_IOMMU_DC_FSC_PDTP_MODE_PD17 = 2,
> > > > > +       RISCV_IOMMU_DC_FSC_PDTP_MODE_PD20 = 3
> > > > > +};
> > > > > +
> > > > > +/* MSI page table pointer */
> > > > > +#define RISCV_IOMMU_DC_MSIPTP_PPN      RISCV_IOMMU_ATP_PPN_FIELD
> > > > > +#define RISCV_IOMMU_DC_MSIPTP_MODE     RISCV_IOMMU_ATP_MODE_FIELD
> > > > > +#define RISCV_IOMMU_DC_MSIPTP_MODE_OFF 0
> > > > > +#define RISCV_IOMMU_DC_MSIPTP_MODE_FLAT        1
> > > > > +
> > > > > +/* MSI address mask */
> > > > > +#define RISCV_IOMMU_DC_MSI_ADDR_MASK   GENMASK_ULL(51, 0)
> > > > > +
> > > > > +/* MSI address pattern */
> > > > > +#define RISCV_IOMMU_DC_MSI_PATTERN     GENMASK_ULL(51, 0)
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_pc - Process Context
> > > > > + * @ta: Translation Attributes
> > > > > + * @fsc: First stage context
> > > > > + *
> > > > > + * This structure is used for leaf nodes on the Process Directory Table
> > > > > + * See section 2.3 for more details
> > > > > + */
> > > > > +struct riscv_iommu_pc {
> > > > > +       u64 ta;
> > > > > +       u64 fsc;
> > > > > +};
> > > > > +
> > > > > +/* Translation attributes fields */
> > > > > +#define RISCV_IOMMU_PC_TA_V    BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_PC_TA_ENS  BIT_ULL(1)
> > > > > +#define RISCV_IOMMU_PC_TA_SUM  BIT_ULL(2)
> > > > > +#define RISCV_IOMMU_PC_TA_PSCID        GENMASK_ULL(31, 12)
> > > > > +
> > > > > +/* First stage context fields */
> > > > > +#define RISCV_IOMMU_PC_FSC_PPN RISCV_IOMMU_ATP_PPN_FIELD
> > > > > +#define RISCV_IOMMU_PC_FSC_MODE        RISCV_IOMMU_ATP_MODE_FIELD
> > > > > +
> > > > > +/*
> > > > > + * Chapter 3: In-memory queue interface
> > > > > + */
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_command - Generic I/O MMU command structure
> > > > > + * @dword0: Includes the opcode and the function identifier
> > > > > + * @dword1: Opcode specific data
> > > > > + *
> > > > > + * The commands are interpreted as two 64bit fields, where the first
> > > > > + * 7bits of the first field are the opcode which also defines the
> > > > > + * command's format, followed by a 3bit field that specifies the
> > > > > + * function invoked by that command, and the rest is opcode-specific.
> > > > > + * This is a generic struct which will be populated differently
> > > > > + * according to each command. For more infos on the commands and
> > > > > + * the command queue check section 3.1.
> > > > > + */
> > > > > +struct riscv_iommu_command {
> > > > > +       u64 dword0;
> > > > > +       u64 dword1;
> > > > > +};
> > > > > +
> > > > > +/* Fields on dword0, common for all commands */
> > > > > +#define RISCV_IOMMU_CMD_OPCODE GENMASK_ULL(6, 0)
> > > > > +#define        RISCV_IOMMU_CMD_FUNC    GENMASK_ULL(9, 7)
> > > > > +
> > > > > +/* 3.1.1 I/O MMU Page-table cache invalidation */
> > > > > +/* Fields on dword0 */
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_OPCODE                1
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_FUNC_VMA      0
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_FUNC_GVMA     1
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_AV            BIT_ULL(10)
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_PSCID         GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_PSCV          BIT_ULL(32)
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_GV            BIT_ULL(33)
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_GSCID         GENMASK_ULL(59, 44)
> > > > > +/* dword1[61:10] is the 4K-aligned page address */
> > > > > +#define RISCV_IOMMU_CMD_IOTINVAL_ADDR          GENMASK_ULL(61, 10)
> > > > > +
> > > > > +/* 3.1.2 I/O MMU Command Queue Fences */
> > > > > +/* Fields on dword0 */
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_OPCODE         2
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_FUNC_C         0
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_AV             BIT_ULL(10)
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_WSI            BIT_ULL(11)
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_PR             BIT_ULL(12)
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_PW             BIT_ULL(13)
> > > > > +#define RISCV_IOMMU_CMD_IOFENCE_DATA           GENMASK_ULL(63, 32)
> > > > > +/* dword1 is the address, word-size aligned and shifted to the right by two bits. */
> > > > > +
> > > > > +/* 3.1.3 I/O MMU Directory cache invalidation */
> > > > > +/* Fields on dword0 */
> > > > > +#define RISCV_IOMMU_CMD_IODIR_OPCODE           3
> > > > > +#define RISCV_IOMMU_CMD_IODIR_FUNC_INVAL_DDT   0
> > > > > +#define RISCV_IOMMU_CMD_IODIR_FUNC_INVAL_PDT   1
> > > > > +#define RISCV_IOMMU_CMD_IODIR_PID              GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_CMD_IODIR_DV               BIT_ULL(33)
> > > > > +#define RISCV_IOMMU_CMD_IODIR_DID              GENMASK_ULL(63, 40)
> > > > > +/* dword1 is reserved for standard use */
> > > > > +
> > > > > +/* 3.1.4 I/O MMU PCIe ATS */
> > > > > +/* Fields on dword0 */
> > > > > +#define RISCV_IOMMU_CMD_ATS_OPCODE             4
> > > > > +#define RISCV_IOMMU_CMD_ATS_FUNC_INVAL         0
> > > > > +#define RISCV_IOMMU_CMD_ATS_FUNC_PRGR          1
> > > > > +#define RISCV_IOMMU_CMD_ATS_PID                        GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_CMD_ATS_PV                 BIT_ULL(32)
> > > > > +#define RISCV_IOMMU_CMD_ATS_DSV                        BIT_ULL(33)
> > > > > +#define RISCV_IOMMU_CMD_ATS_RID                        GENMASK_ULL(55, 40)
> > > > > +#define RISCV_IOMMU_CMD_ATS_DSEG               GENMASK_ULL(63, 56)
> > > > > +/* dword1 is the ATS payload, two different payload types for INVAL and PRGR */
> > > > > +
> > > > > +/* ATS.INVAL payload*/
> > > > > +#define RISCV_IOMMU_CMD_ATS_INVAL_G            BIT_ULL(0)
> > > > > +/* Bits 1 - 10 are zeroed */
> > > > > +#define RISCV_IOMMU_CMD_ATS_INVAL_S            BIT_ULL(11)
> > > > > +#define RISCV_IOMMU_CMD_ATS_INVAL_UADDR                GENMASK_ULL(63, 12)
> > > > > +
> > > > > +/* ATS.PRGR payload */
> > > > > +/* Bits 0 - 31 are zeroed */
> > > > > +#define RISCV_IOMMU_CMD_ATS_PRGR_PRG_INDEX     GENMASK_ULL(40, 32)
> > > > > +/* Bits 41 - 43 are zeroed */
> > > > > +#define RISCV_IOMMU_CMD_ATS_PRGR_RESP_CODE     GENMASK_ULL(47, 44)
> > > > > +#define RISCV_IOMMU_CMD_ATS_PRGR_DST_ID                GENMASK_ULL(63, 48)
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_fq_record - Fault/Event Queue Record
> > > > > + * @hdr: Header, includes fault/event cause, PID/DID, transaction type etc
> > > > > + * @_reserved: Low 32bits for custom use, high 32bits for standard use
> > > > > + * @iotval: Transaction-type/cause specific format
> > > > > + * @iotval2: Cause specific format
> > > > > + *
> > > > > + * The fault/event queue reports events and failures raised when
> > > > > + * processing transactions. Each record is a 32byte structure where
> > > > > + * the first dword has a fixed format for providing generic infos
> > > > > + * regarding the fault/event, and two more dwords are there for
> > > > > + * fault/event-specific information. For more details see section
> > > > > + * 3.2.
> > > > > + */
> > > > > +struct riscv_iommu_fq_record {
> > > > > +       u64 hdr;
> > > > > +       u64 _reserved;
> > > > > +       u64 iotval;
> > > > > +       u64 iotval2;
> > > > > +};
> > > > > +
> > > > > +/* Fields on header */
> > > > > +#define RISCV_IOMMU_FQ_HDR_CAUSE       GENMASK_ULL(11, 0)
> > > > > +#define RISCV_IOMMU_FQ_HDR_PID         GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_FQ_HDR_PV          BIT_ULL(32)
> > > > > +#define RISCV_IOMMU_FQ_HDR_PRIV                BIT_ULL(33)
> > > > > +#define RISCV_IOMMU_FQ_HDR_TTYPE       GENMASK_ULL(39, 34)
> > > > > +#define RISCV_IOMMU_FQ_HDR_DID         GENMASK_ULL(63, 40)
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_fq_causes - Fault/event cause values
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_INST_FAULT: Instruction access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_RD_ADDR_MISALIGNED: Read address misaligned
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_RD_FAULT: Read load fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_WR_ADDR_MISALIGNED: Write/AMO address misaligned
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_WR_FAULT: Write/AMO access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_INST_FAULT_S: Instruction page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_RD_FAULT_S: Read page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_WR_FAULT_S: Write/AMO page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_INST_FAULT_VS: Instruction guest page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_RD_FAULT_VS: Read guest page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_WR_FAULT_VS: Write/AMO guest page fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_DMA_DISABLED: All inbound transactions disallowed
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_DDT_LOAD_FAULT: DDT entry load access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_DDT_INVALID: DDT entry invalid
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_DDT_MISCONFIGURED: DDT entry misconfigured
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_TTYPE_BLOCKED: Transaction type disallowed
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MSI_LOAD_FAULT: MSI PTE load access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MSI_INVALID: MSI PTE invalid
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MSI_MISCONFIGURED: MSI PTE misconfigured
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MRIF_FAULT: MRIF access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_PDT_LOAD_FAULT: PDT entry load access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_PDT_INVALID: PDT entry invalid
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_PDT_MISCONFIGURED: PDT entry misconfigured
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_DDT_CORRUPTED: DDT data corruption
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_PDT_CORRUPTED: PDT data corruption
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MSI_PT_CORRUPTED: MSI page table data corruption
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MRIF_CORRUIPTED: MRIF data corruption
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_INTERNAL_DP_ERROR: Internal data path error
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_MSI_WR_FAULT: IOMMU MSI write access fault
> > > > > + * @RISCV_IOMMU_FQ_CAUSE_PT_CORRUPTED: First/second stage page table data corruption
> > > > > + *
> > > > > + * Values are on table 11 of the spec, encodings 275 - 2047 are reserved for standard
> > > > > + * use, and 2048 - 4095 for custom use.
> > > > > + */
> > > > > +enum riscv_iommu_fq_causes {
> > > > > +       RISCV_IOMMU_FQ_CAUSE_INST_FAULT = 1,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_RD_ADDR_MISALIGNED = 4,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_RD_FAULT = 5,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_WR_ADDR_MISALIGNED = 6,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_WR_FAULT = 7,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_INST_FAULT_S = 12,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_RD_FAULT_S = 13,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_WR_FAULT_S = 15,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_INST_FAULT_VS = 20,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_RD_FAULT_VS = 21,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_WR_FAULT_VS = 23,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_DMA_DISABLED = 256,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_DDT_LOAD_FAULT = 257,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_DDT_INVALID = 258,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_DDT_MISCONFIGURED = 259,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_TTYPE_BLOCKED = 260,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MSI_LOAD_FAULT = 261,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MSI_INVALID = 262,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MSI_MISCONFIGURED = 263,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MRIF_FAULT = 264,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_PDT_LOAD_FAULT = 265,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_PDT_INVALID = 266,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_PDT_MISCONFIGURED = 267,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_DDT_CORRUPTED = 268,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_PDT_CORRUPTED = 269,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MSI_PT_CORRUPTED = 270,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MRIF_CORRUIPTED = 271,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_INTERNAL_DP_ERROR = 272,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_MSI_WR_FAULT = 273,
> > > > > +       RISCV_IOMMU_FQ_CAUSE_PT_CORRUPTED = 274
> > > > > +};
> > > > > +
> > > > > +/**
> > > > > + * enum riscv_iommu_fq_ttypes: Fault/event transaction types
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_NONE: None. Fault not caused by an inbound transaction.
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_UADDR_INST_FETCH: Instruction fetch from untranslated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_UADDR_RD: Read from untranslated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_UADDR_WR: Write/AMO to untranslated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_TADDR_INST_FETCH: Instruction fetch from translated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_TADDR_RD: Read from translated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_TADDR_WR: Write/AMO to translated address
> > > > > + * @RISCV_IOMMU_FQ_TTYPE_PCIE_ATS_REQ: PCIe ATS translation request
> > > > > + * @RISCV_IOMMU_FW_TTYPE_PCIE_MSG_REQ: PCIe message request
> > > > > + *
> > > > > + * Values are on table 12 of the spec, type 4 and 10 - 31 are reserved for standard use
> > > > > + * and 31 - 63 for custom use.
> > > > > + */
> > > > > +enum riscv_iommu_fq_ttypes {
> > > > > +       RISCV_IOMMU_FQ_TTYPE_NONE = 0,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_UADDR_INST_FETCH = 1,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_UADDR_RD = 2,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_UADDR_WR = 3,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_TADDR_INST_FETCH = 5,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_TADDR_RD = 6,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_TADDR_WR = 7,
> > > > > +       RISCV_IOMMU_FQ_TTYPE_PCIE_ATS_REQ = 8,
> > > > > +       RISCV_IOMMU_FW_TTYPE_PCIE_MSG_REQ = 9,
> > > > > +};
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_pq_record - PCIe Page Request record
> > > > > + * @hdr: Header, includes PID, DID etc
> > > > > + * @payload: Holds the page address, request group and permission bits
> > > > > + *
> > > > > + * For more infos on the PCIe Page Request queue see chapter 3.3.
> > > > > + */
> > > > > +struct riscv_iommu_pq_record {
> > > > > +       u64 hdr;
> > > > > +       u64 payload;
> > > > > +};
> > > > > +
> > > > > +/* Header fields */
> > > > > +#define RISCV_IOMMU_PREQ_HDR_PID       GENMASK_ULL(31, 12)
> > > > > +#define RISCV_IOMMU_PREQ_HDR_PV                BIT_ULL(32)
> > > > > +#define RISCV_IOMMU_PREQ_HDR_PRIV      BIT_ULL(33)
> > > > > +#define RISCV_IOMMU_PREQ_HDR_EXEC      BIT_ULL(34)
> > > > > +#define RISCV_IOMMU_PREQ_HDR_DID       GENMASK_ULL(63, 40)
> > > > > +
> > > > > +/* Payload fields */
> > > > > +#define RISCV_IOMMU_PREQ_PAYLOAD_R     BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_PREQ_PAYLOAD_W     BIT_ULL(1)
> > > > > +#define RISCV_IOMMU_PREQ_PAYLOAD_L     BIT_ULL(2)
> > > > > +#define RISCV_IOMMU_PREQ_PAYLOAD_M     GENMASK_ULL(2, 0)       /* Mask of RWL for convenience */
> > > > > +#define RISCV_IOMMU_PREQ_PRG_INDEX     GENMASK_ULL(11, 3)
> > > > > +#define RISCV_IOMMU_PREQ_UADDR         GENMASK_ULL(63, 12)
> > > > > +
> > > > > +/**
> > > > > + * struct riscv_iommu_msi_pte - MSI Page Table Entry
> > > > > + * @pte: MSI PTE
> > > > > + * @mrif_info: Memory-resident interrupt file info
> > > > > + *
> > > > > + * The MSI Page Table is used for virtualizing MSIs, so that when
> > > > > + * a device sends an MSI to a guest, the IOMMU can reroute it
> > > > > + * by translating the MSI address, either to a guest interrupt file
> > > > > + * or a memory resident interrupt file (MRIF). Note that this page table
> > > > > + * is an array of MSI PTEs, not a multi-level pt, each entry
> > > > > + * is a leaf entry. For more infos check out the AIA spec, chapter 9.5.
> > > > > + *
> > > > > + * Also in basic mode the mrif_info field is ignored by the IOMMU and can
> > > > > + * be used by software, any other reserved fields on pte must be zeroed-out
> > > > > + * by software.
> > > > > + */
> > > > > +struct riscv_iommu_msi_pte {
> > > > > +       u64 pte;
> > > > > +       u64 mrif_info;
> > > > > +};
> > > > > +
> > > > > +/* Fields on pte */
> > > > > +#define RISCV_IOMMU_MSI_PTE_V          BIT_ULL(0)
> > > > > +#define RISCV_IOMMU_MSI_PTE_M          GENMASK_ULL(2, 1)
> > > > > +#define RISCV_IOMMU_MSI_PTE_MRIF_ADDR  GENMASK_ULL(53, 7)      /* When M == 1 (MRIF mode) */
> > > > > +#define RISCV_IOMMU_MSI_PTE_PPN                RISCV_IOMMU_PPN_FIELD   /* When M == 3 (basic mode) */
> > > > > +#define RISCV_IOMMU_MSI_PTE_C          BIT_ULL(63)
> > > > > +
> > > > > +/* Fields on mrif_info */
> > > > > +#define RISCV_IOMMU_MSI_MRIF_NID       GENMASK_ULL(9, 0)
> > > > > +#define RISCV_IOMMU_MSI_MRIF_NPPN      RISCV_IOMMU_PPN_FIELD
> > > > > +#define RISCV_IOMMU_MSI_MRIF_NID_MSB   BIT_ULL(60)
> > > > > +
> > > > > +#endif /* _RISCV_IOMMU_BITS_H_ */
> > > > > diff --git a/drivers/iommu/riscv/iommu-platform.c b/drivers/iommu/riscv/iommu-platform.c
> > > > > new file mode 100644
> > > > > index 000000000000..1b453334fbbe
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/iommu-platform.c
> > > > > @@ -0,0 +1,92 @@
> > > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > > +/*
> > > > > + * RISC-V IOMMU as a platform device
> > > > > + *
> > > > > + * Copyright © 2023 FORTH-ICS/CARV
> > > > > + * Copyright © 2023-2024 Rivos Inc.
> > > > > + *
> > > > > + * Authors
> > > > > + *     Nick Kossifidis <mick at ics.forth.gr>
> > > > > + *     Tomasz Jeznach <tjeznach at rivosinc.com>
> > > > > + */
> > > > > +
> > > > > +#include <linux/kernel.h>
> > > > > +#include <linux/of_platform.h>
> > > > > +#include <linux/platform_device.h>
> > > > > +
> > > > > +#include "iommu-bits.h"
> > > > > +#include "iommu.h"
> > > > > +
> > > > > +static int riscv_iommu_platform_probe(struct platform_device *pdev)
> > > > > +{
> > > > > +       struct device *dev = &pdev->dev;
> > > > > +       struct riscv_iommu_device *iommu = NULL;
> > > > > +       struct resource *res = NULL;
> > > > > +       int vec;
> > > > > +
> > > > > +       iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL);
> > > > > +       if (!iommu)
> > > > > +               return -ENOMEM;
> > > > > +
> > > > > +       iommu->dev = dev;
> > > > > +       iommu->reg = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> > > > > +       if (IS_ERR(iommu->reg))
> > > > > +               return dev_err_probe(dev, PTR_ERR(iommu->reg),
> > > > > +                                    "could not map register region\n");
> > > > > +
> > > > > +       dev_set_drvdata(dev, iommu);
> > > > > +
> > > > > +       /* Check device reported capabilities / features. */
> > > > > +       iommu->caps = riscv_iommu_readq(iommu, RISCV_IOMMU_REG_CAP);
> > > > > +       iommu->fctl = riscv_iommu_readl(iommu, RISCV_IOMMU_REG_FCTL);
> > > > > +
> > > > > +       /* For now we only support WSI */
> > > > > +       switch (FIELD_GET(RISCV_IOMMU_CAP_IGS, iommu->caps)) {
> > > > > +       case RISCV_IOMMU_CAP_IGS_WSI:
> > > > > +       case RISCV_IOMMU_CAP_IGS_BOTH:
> > > > > +               break;
> > > > > +       default:
> > > > > +               return dev_err_probe(dev, -ENODEV,
> > > > > +                                    "unable to use wire-signaled interrupts\n");
> > > > > +       }
> > > > > +
> > > > > +       iommu->irqs_count = platform_irq_count(pdev);
> > > > > +       if (iommu->irqs_count <= 0)
> > > > > +               return dev_err_probe(dev, -ENODEV,
> > > > > +                                    "no IRQ resources provided\n");
> > > > > +       if (iommu->irqs_count > RISCV_IOMMU_INTR_COUNT)
> > > > > +               iommu->irqs_count = RISCV_IOMMU_INTR_COUNT;
> > > > > +
> > > > > +       for (vec = 0; vec < iommu->irqs_count; vec++)
> > > > > +               iommu->irqs[vec] = platform_get_irq(pdev, vec);
> > > > > +
> > > > > +       /* Enable wire-signaled interrupts, fctl.WSI */
> > > > > +       if (!(iommu->fctl & RISCV_IOMMU_FCTL_WSI)) {
> > > > > +               iommu->fctl |= RISCV_IOMMU_FCTL_WSI;
> > > > > +               riscv_iommu_writel(iommu, RISCV_IOMMU_REG_FCTL, iommu->fctl);
> > > > > +       }
> > > > > +
> > > > > +       return riscv_iommu_init(iommu);
> > > > > +};
> > > > > +
> > > > > +static void riscv_iommu_platform_remove(struct platform_device *pdev)
> > > > > +{
> > > > > +       riscv_iommu_remove(dev_get_drvdata(&pdev->dev));
> > > > > +};
> > > > > +
> > > > > +static const struct of_device_id riscv_iommu_of_match[] = {
> > > > > +       {.compatible = "riscv,iommu",},
> > > > > +       {},
> > > > > +};
> > > > > +
> > > > > +static struct platform_driver riscv_iommu_platform_driver = {
> > > > > +       .probe = riscv_iommu_platform_probe,
> > > > > +       .remove_new = riscv_iommu_platform_remove,
> > > > > +       .driver = {
> > > > > +               .name = "riscv,iommu",
> > > > > +               .of_match_table = riscv_iommu_of_match,
> > > > > +               .suppress_bind_attrs = true,
> > > > > +       },
> > > > > +};
> > > > > +
> > > > > +builtin_platform_driver(riscv_iommu_platform_driver);
> > > > > diff --git a/drivers/iommu/riscv/iommu.c b/drivers/iommu/riscv/iommu.c
> > > > > new file mode 100644
> > > > > index 000000000000..3c5a6b49669d
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/iommu.c
> > > > > @@ -0,0 +1,99 @@
> > > > > +// SPDX-License-Identifier: GPL-2.0-only
> > > > > +/*
> > > > > + * IOMMU API for RISC-V IOMMU implementations.
> > > > > + *
> > > > > + * Copyright © 2022-2024 Rivos Inc.
> > > > > + * Copyright © 2023 FORTH-ICS/CARV
> > > > > + *
> > > > > + * Authors
> > > > > + *     Tomasz Jeznach <tjeznach at rivosinc.com>
> > > > > + *     Nick Kossifidis <mick at ics.forth.gr>
> > > > > + */
> > > > > +
> > > > > +#define pr_fmt(fmt) "riscv-iommu: " fmt
> > > > > +
> > > > > +#include <linux/compiler.h>
> > > > > +#include <linux/crash_dump.h>
> > > > > +#include <linux/init.h>
> > > > > +#include <linux/iommu.h>
> > > > > +#include <linux/kernel.h>
> > > > > +
> > > > > +#include "iommu-bits.h"
> > > > > +#include "iommu.h"
> > > > > +
> > > > > +/* Timeouts in [us] */
> > > > > +#define RISCV_IOMMU_DDTP_TIMEOUT       50000
> > > > > +
> > > > > +/*
> > > > > + * This is best effort IOMMU translation shutdown flow.
> > > > > + * Disable IOMMU without waiting for hardware response.
> > > > > + */
> > > > > +static void riscv_iommu_disable(struct riscv_iommu_device *iommu)
> > > > > +{
> > > > > +       riscv_iommu_writeq(iommu, RISCV_IOMMU_REG_DDTP, 0);
> > > > > +       riscv_iommu_writel(iommu, RISCV_IOMMU_REG_CQCSR, 0);
> > > > > +       riscv_iommu_writel(iommu, RISCV_IOMMU_REG_FQCSR, 0);
> > > > > +       riscv_iommu_writel(iommu, RISCV_IOMMU_REG_PQCSR, 0);
> > > > > +}
> > > > > +
> > > > > +static int riscv_iommu_init_check(struct riscv_iommu_device *iommu)
> > > > > +{
> > > > > +       u64 ddtp;
> > > > > +
> > > > > +       /*
> > > > > +        * Make sure the IOMMU is switched off or in pass-through mode during
> > > > > +        * regular boot flow and disable translation when we boot into a kexec
> > > > > +        * kernel and the previous kernel left them enabled.
> > > > > +        */
> > > > > +       ddtp = riscv_iommu_readq(iommu, RISCV_IOMMU_REG_DDTP);
> > > > > +       if (ddtp & RISCV_IOMMU_DDTP_BUSY)
> > > > > +               return -EBUSY;
> > > > > +
> > > > > +       if (FIELD_GET(RISCV_IOMMU_DDTP_MODE, ddtp) > RISCV_IOMMU_DDTP_MODE_BARE) {
> > > > > +               if (!is_kdump_kernel())
> > > > > +                       return -EBUSY;
> > > > > +               riscv_iommu_disable(iommu);
> > > > > +       }
> > > > > +
> > > > > +       /* Configure accesses to in-memory data structures for CPU-native byte order. */
> > > > > +       if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) != !!(iommu->fctl & RISCV_IOMMU_FCTL_BE)) {
> > > > > +               if (!(iommu->caps & RISCV_IOMMU_CAP_END))
> > > > > +                       return -EINVAL;
> > > > > +               riscv_iommu_writel(iommu, RISCV_IOMMU_REG_FCTL,
> > > > > +                                  iommu->fctl ^ RISCV_IOMMU_FCTL_BE);
> > > > > +               iommu->fctl = riscv_iommu_readl(iommu, RISCV_IOMMU_REG_FCTL);
> > > > > +               if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) != !!(iommu->fctl & RISCV_IOMMU_FCTL_BE))
> > > > > +                       return -EINVAL;
> > > > > +       }
> > > > > +
> > > > > +       return 0;
> > > > > +}
> > > > > +
> > > > > +void riscv_iommu_remove(struct riscv_iommu_device *iommu)
> > > > > +{
> > > > > +       iommu_device_sysfs_remove(&iommu->iommu);
> > > > > +}
> > > > > +
> > > > > +int riscv_iommu_init(struct riscv_iommu_device *iommu)
> > > > > +{
> > > > > +       int rc;
> > > > > +
> > > > > +       rc = riscv_iommu_init_check(iommu);
> > > > > +       if (rc)
> > > > > +               return dev_err_probe(iommu->dev, rc, "unexpected device state\n");
> > > > > +
> > > > > +       /*
> > > > > +        * Placeholder for a complete IOMMU device initialization.  For now,
> > > > > +        * only bare minimum: enable global identity mapping mode and register sysfs.
> > > > > +        */
> > > > > +       riscv_iommu_writeq(iommu, RISCV_IOMMU_REG_DDTP,
> > > > > +                          FIELD_PREP(RISCV_IOMMU_DDTP_MODE, RISCV_IOMMU_DDTP_MODE_BARE));
> > > > > +
> > > > > +       rc = iommu_device_sysfs_add(&iommu->iommu, NULL, NULL, "riscv-iommu@%s",
> > > > > +                                   dev_name(iommu->dev));
> > > > > +       if (rc)
> > > > > +               return dev_err_probe(iommu->dev, rc,
> > > > > +                                    "cannot register sysfs interface\n");
> > > > > +
> > > > > +       return 0;
> > > > > +}
> > > > > diff --git a/drivers/iommu/riscv/iommu.h b/drivers/iommu/riscv/iommu.h
> > > > > new file mode 100644
> > > > > index 000000000000..700e33dc2446
> > > > > --- /dev/null
> > > > > +++ b/drivers/iommu/riscv/iommu.h
> > > > > @@ -0,0 +1,62 @@
> > > > > +/* SPDX-License-Identifier: GPL-2.0-only */
> > > > > +/*
> > > > > + * Copyright © 2022-2024 Rivos Inc.
> > > > > + * Copyright © 2023 FORTH-ICS/CARV
> > > > > + *
> > > > > + * Authors
> > > > > + *     Tomasz Jeznach <tjeznach at rivosinc.com>
> > > > > + *     Nick Kossifidis <mick at ics.forth.gr>
> > > > > + */
> > > > > +
> > > > > +#ifndef _RISCV_IOMMU_H_
> > > > > +#define _RISCV_IOMMU_H_
> > > > > +
> > > > > +#include <linux/iommu.h>
> > > > > +#include <linux/types.h>
> > > > > +#include <linux/iopoll.h>
> > > > > +
> > > > > +#include "iommu-bits.h"
> > > > > +
> > > > > +struct riscv_iommu_device {
> > > > > +       /* iommu core interface */
> > > > > +       struct iommu_device iommu;
> > > > > +
> > > > > +       /* iommu hardware */
> > > > > +       struct device *dev;
> > > > > +
> > > > > +       /* hardware control register space */
> > > > > +       void __iomem *reg;
> > > > > +
> > > > > +       /* supported and enabled hardware capabilities */
> > > > > +       u64 caps;
> > > > > +       u32 fctl;
> > > > > +
> > > > > +       /* available interrupt numbers, MSI or WSI */
> > > > > +       unsigned int irqs[RISCV_IOMMU_INTR_COUNT];
> > > > > +       unsigned int irqs_count;
> > > > > +};
> > > > > +
> > > > > +int riscv_iommu_init(struct riscv_iommu_device *iommu);
> > > > > +void riscv_iommu_remove(struct riscv_iommu_device *iommu);
> > > > > +
> > > > > +#define riscv_iommu_readl(iommu, addr) \
> > > > > +       readl_relaxed((iommu)->reg + (addr))
> > > > > +
> > > > > +#define riscv_iommu_readq(iommu, addr) \
> > > > > +       readq_relaxed((iommu)->reg + (addr))
> > > > > +
> > > > > +#define riscv_iommu_writel(iommu, addr, val) \
> > > > > +       writel_relaxed((val), (iommu)->reg + (addr))
> > > > > +
> > > > > +#define riscv_iommu_writeq(iommu, addr, val) \
> > > > > +       writeq_relaxed((val), (iommu)->reg + (addr))
> > > > > +
> > > > > +#define riscv_iommu_readq_timeout(iommu, addr, val, cond, delay_us, timeout_us) \
> > > > > +       readx_poll_timeout(readq_relaxed, (iommu)->reg + (addr), val, cond, \
> > > > > +                          delay_us, timeout_us)
> > > > > +
> > > > > +#define riscv_iommu_readl_timeout(iommu, addr, val, cond, delay_us, timeout_us) \
> > > > > +       readx_poll_timeout(readl_relaxed, (iommu)->reg + (addr), val, cond, \
> > > > > +                          delay_us, timeout_us)
> > > > > +
> > > > > +#endif
> > > > > --
> > > > > 2.34.1
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > linux-riscv mailing list
> > > > > linux-riscv at lists.infradead.org
> > > > > http://lists.infradead.org/mailman/listinfo/linux-riscv



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