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Message-ID: <68e3a7ab-0387-3e58-8c30-3ace807acee5@linux.intel.com>
Date:   Thu, 20 Jul 2023 18:38:37 +0800
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Cc:     baolu.lu@linux.intel.com, Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Anup Patel <apatel@ventanamicro.com>,
        Sunil V L <sunilvl@ventanamicro.com>,
        Nick Kossifidis <mick@ics.forth.gr>,
        Sebastien Boeuf <seb@rivosinc.com>, iommu@lists.linux.dev,
        linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux@rivosinc.com
Subject: Re: [PATCH 01/11] RISC-V: drivers/iommu: Add RISC-V IOMMU - Ziommu
 support.
Content-Language: en-US
To:     Tomasz Jeznach <tjeznach@rivosinc.com>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Paul Walmsley <paul.walmsley@sifive.com>
References: <cover.1689792825.git.tjeznach@rivosinc.com>
 <c33c24036c06c023947ecb47177da273569b3ac7.1689792825.git.tjeznach@rivosinc.com>
From:   Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <c33c24036c06c023947ecb47177da273569b3ac7.1689792825.git.tjeznach@rivosinc.com>
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On 2023/7/20 3:33, Tomasz Jeznach wrote:
> +struct riscv_iommu_domain {
> +	struct iommu_domain domain;
> +
> +	struct list_head endpoints;
> +	struct mutex lock;
> +	struct riscv_iommu_device *iommu;

How are domains and iommu devices connected? A domain can be attached to
multiple devices, which are possibly behind different iommu devices. So
a domain is possibly connected to multiple iommu devices.

Is it possible?

> +
> +	unsigned mode;		/* RIO_ATP_MODE_* enum */
> +	unsigned pscid;		/* RISC-V IOMMU PSCID */
> +
> +	pgd_t *pgd_root;	/* page table root pointer */
> +};
> +
> +/* Private dev_iommu_priv object, device-domain relationship. */
> +struct riscv_iommu_endpoint {
> +	struct device *dev;			/* platform or PCI endpoint device */
> +	unsigned devid;      			/* PCI bus:device:function number */
> +	unsigned domid;    			/* PCI domain number, segment */
> +	struct rb_node node;    		/* device tracking node (lookup by devid) */
> +	struct riscv_iommu_device *iommu;	/* parent iommu device */
> +
> +	struct mutex lock;
> +	struct list_head domain;		/* endpoint attached managed domain */
> +};

Best regards,
baolu