Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v2 06/36] irqchip/gic-v3-its: Kill its->device_ids and use
 TYPER copy instead
To:     Marc Zyngier <maz@kernel.org>, <kvmarm@lists.cs.columbia.edu>,
        <linux-kernel@vger.kernel.org>
CC:     Eric Auger <eric.auger@redhat.com>,
        James Morse <james.morse@arm.com>,
        Julien Thierry <julien.thierry.kdev@gmail.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Jason Cooper <jason@lakedaemon.net>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        "Andrew Murray" <Andrew.Murray@arm.com>,
        Jayachandran C <jnair@marvell.com>,
        "Robert Richter" <rrichter@marvell.com>
References: <20191027144234.8395-1-maz@kernel.org>
 <20191027144234.8395-7-maz@kernel.org>
From:   Zenghui Yu <yuzenghui@huawei.com>
Message-ID: <603e60d8-b2a5-74a4-6d32-8277aa0e39c1@huawei.com>
Date:   Thu, 31 Oct 2019 14:33:23 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101
 Thunderbird/68.2.0
MIME-Version: 1.0
In-Reply-To: <20191027144234.8395-7-maz@kernel.org>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Marc,

On 2019/10/27 22:42, Marc Zyngier wrote:
> Now that we have a copy of TYPER in the ITS structure, rely on this
> to provide the same service as its->device_ids, which gets axed.
> Errata workarounds are now updating the cached fields instead of
> requiring a separate field in the ITS structure.
> 
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>

> ---
>   drivers/irqchip/irq-gic-v3-its.c   | 24 +++++++++++++-----------
>   include/linux/irqchip/arm-gic-v3.h |  2 +-
>   2 files changed, 14 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 3b046181ddfc..6c91c7feadf3 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -109,7 +109,6 @@ struct its_node {
>   	struct list_head	its_device_list;
>   	u64			flags;
>   	unsigned long		list_nr;
> -	u32			device_ids;
>   	int			numa_node;
>   	unsigned int		msi_domain_flags;
>   	u32			pre_its_base; /* for Socionext Synquacer */
> @@ -117,6 +116,7 @@ struct its_node {
>   };
>   
>   #define is_v4(its)		(!!((its)->typer & GITS_TYPER_VLPIS))
> +#define device_ids(its)		(FIELD_GET(GITS_TYPER_DEVBITS, (its)->typer) + 1)
>   
>   #define ITS_ITT_ALIGN		SZ_256
>   
> @@ -1938,9 +1938,9 @@ static bool its_parse_indirect_baser(struct its_node *its,
>   	if (new_order >= MAX_ORDER) {
>   		new_order = MAX_ORDER - 1;
>   		ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz);
> -		pr_warn("ITS@%pa: %s Table too large, reduce ids %u->%u\n",
> +		pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n",
>   			&its->phys_base, its_base_type_string[type],
> -			its->device_ids, ids);
> +			device_ids(its), ids);

But this pr_warn() looks a bit odd. The table type is chosen from
its_base_type_string[], but ids is always Devbits (+1)?


Thanks,
Zenghui