Re: [PATCH v6 2/7] iommu/riscv: Add RISC-V IOMMU platform device driver
From: Andrew Jones
Date: Wed May 29 2024 - 11:16:30 EST
Hi Tomasz,
I reviewed iommu-bits.h to the spec. Most naming matches exactly, which
is nice, but I've pointed out a few which don't.
Thanks,
drew
On Fri, May 24, 2024 at 12:34:42PM GMT, Tomasz Jeznach wrote:
..
> 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)
RISCV_IOMMU_QUEUE_LOG2SZ_FIELD
> +#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
Maybe too verbose, but the name is "capabilities". So all the below 'CAP'
instances would match the spec better if spelled out.
> +#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)
RISCV_IOMMU_CAPABILITIES_SV32X4
RISCV_IOMMU_CAPABILITIES_SV39X4
RISCV_IOMMU_CAPABILITIES_SV48X4
RISCV_IOMMU_CAPABILITIES_SV57X4
> +#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
RISCV_IOMMU_CAP_VERSION_MAJOR_MASK
> +#define RISCV_IOMMU_CAP_VERSION_REV_MASK 0x0F
RISCV_IOMMU_CAP_VERSION_MINOR_MASK
> +
> +/**
> + * 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
Can we always spell IOMMU 'IOMMU'?
> + * @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)
A bit unnecessary, but spec calls this 'iommu_mode', so
RISCV_IOMMU_DDTP_IOMMU_MODE ?
> +#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_PN RISCV_IOMMU_PPN_FIELD
RISCV_IOMMU_FQB_PPN
> +
> +/* 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)
RISCV_IOMMU_REG_IOCNTOVF* for all above. It looks like this
got renamed and the header of the spec subsection still has
the old name, but otherwise the new name is referenced.
> +
> +/* 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)
RISCV_IOMMU_IOCNTINH* for all above. Same header with old
name spec issue.
> +
> +/* 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)
RISCV_IOMMU_IOHPMCYCLES_OF
> +
> +/* 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
What is RISCV_IOMMU_IOHPMEVT_CNT ?
> +#define RISCV_IOMMU_IOHPMEVT_EVENT_ID GENMASK_ULL(14, 0)
RISCV_IOMMU_IOHPMEVT_EVENTID (EVENT_ID reads nicer though...)
> +#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
Let's copy+paste these descriptions from the spec to allow them to be
copy+pasted from here into a search in the spec. (Most already mostly
match, except for the G-stage vs. second-stage type stuff.)
> + * @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)
RISCV_IOMMU_TR_RESPONSE_S (although SZ is easier to understand...)
> +#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)
RISCV_IOMMU_REG_MSI_CFG_TBL for all above
> +
> +#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)
RISCV_IOMMU_DDTE_V
> +#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)
RISCV_IOMMU_CMD_IOTDIR_* for all above
> +/* 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)
RISCV_IOMMU_FQ_HDR_TTYP
> +#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,
> +};
RISCV_IOMMU_FW_TTYP_* for all above
> +
> +/**
> + * 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 */
Maybe RISCV_IOMMU_PREQ_PAYLOAD_RWL_MASK ? Just 'M' doesn't convey anything
so it makes one want to look it up in the spec.
> +#define RISCV_IOMMU_PREQ_PRG_INDEX GENMASK_ULL(11, 3)
> +#define RISCV_IOMMU_PREQ_UADDR GENMASK_ULL(63, 12)
RISCV_IOMMU_PQ_HDR_* for all above
> +
> +/**
> + * 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)
RISCV_IOMMU_MSIPTE_* for all above
> +
> +/* 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_ */