Re: [PATCH v2 16/36] irqchip/gic-v4.1: Add mask/unmask doorbell callbacks

From: Marc Zyngier <maz@kernel.org>
To: Zenghui Yu <yuzenghui@huawei.com>
Cc: <kvmarm@lists.cs.columbia.edu>, <linux-kernel@vger.kernel.org>,
	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>
Subject: Re: [PATCH v2 16/36] irqchip/gic-v4.1: Add mask/unmask doorbell  callbacks
Date: Wed, 18 Dec 2019 15:06:30 +0000	[thread overview]
Message-ID: <115f732eec1d960e69ee2b544a0e39b0@www.loen.fr> (raw)
In-Reply-To: <7c94be43-e1b0-625a-762c-ec8589f16b2d@huawei.com>

On 2019-11-01 11:23, Zenghui Yu wrote:
> Hi Marc,
>
> On 2019/10/27 22:42, Marc Zyngier wrote:
>> masking/unmasking doorbells on GICv4.1 relies on a new INVDB 
>> command,
>> which broadcasts the invalidation to all RDs.
>> Implement the new command as well as the masking callbacks, and plug
>> the whole thing into the v4.1 VPE irqchip.
>> Signed-off-by: Marc Zyngier <maz@kernel.org>
>
> Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
>
>> ---
>>   drivers/irqchip/irq-gic-v3-its.c   | 60 
>> ++++++++++++++++++++++++++++++
>>   include/linux/irqchip/arm-gic-v3.h |  3 +-
>>   2 files changed, 62 insertions(+), 1 deletion(-)
>> diff --git a/drivers/irqchip/irq-gic-v3-its.c 
>> b/drivers/irqchip/irq-gic-v3-its.c
>> index dcc7227af5f1..3c34bef70bdd 100644
>> --- a/drivers/irqchip/irq-gic-v3-its.c
>> +++ b/drivers/irqchip/irq-gic-v3-its.c
>> @@ -309,6 +309,10 @@ struct its_cmd_desc {
>>   			u16 seq_num;
>>   			u16 its_list;
>>   		} its_vmovp_cmd;
>> +
>> +		struct {
>> +			struct its_vpe *vpe;
>> +		} its_invdb_cmd;
>>   	};
>>   };
>>   @@ -750,6 +754,21 @@ static struct its_vpe 
>> *its_build_vmovp_cmd(struct its_node *its,
>>   	return valid_vpe(its, desc->its_vmovp_cmd.vpe);
>>   }
>>   +static struct its_vpe *its_build_invdb_cmd(struct its_node *its,
>> +					   struct its_cmd_block *cmd,
>> +					   struct its_cmd_desc *desc)
>> +{
>> +	if (WARN_ON(!is_v4_1(its)))
>> +		return NULL;
>> +
>> +	its_encode_cmd(cmd, GITS_CMD_INVDB);
>> +	its_encode_vpeid(cmd, desc->its_invdb_cmd.vpe->vpe_id);
>> +
>> +	its_fixup_cmd(cmd);
>> +
>> +	return valid_vpe(its, desc->its_invdb_cmd.vpe);
>> +}
>> +
>>   static u64 its_cmd_ptr_to_offset(struct its_node *its,
>>   				 struct its_cmd_block *ptr)
>>   {
>> @@ -1117,6 +1136,14 @@ static void its_send_vinvall(struct its_node 
>> *its, struct its_vpe *vpe)
>>   	its_send_single_vcommand(its, its_build_vinvall_cmd, &desc);
>>   }
>>   +static void its_send_invdb(struct its_node *its, struct its_vpe 
>> *vpe)
>> +{
>> +	struct its_cmd_desc desc;
>> +
>> +	desc.its_invdb_cmd.vpe = vpe;
>> +	its_send_single_vcommand(its, its_build_invdb_cmd, &desc);
>> +}
>> +
>>   /*
>>    * irqchip functions - assumes MSI, mostly.
>>    */
>> @@ -3408,6 +3435,37 @@ static struct irq_chip its_vpe_irq_chip = {
>>   	.irq_set_vcpu_affinity	= its_vpe_set_vcpu_affinity,
>>   };
>>   +static void its_vpe_4_1_send_inv(struct irq_data *d)
>> +{
>> +	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
>> +	struct its_node *its;
>> +
>> +	/*
>> +	 * GICv4.1 wants doorbells to be invalidated using the
>> +	 * INVDB command in order to be broadcast to all RDs. Send
>> +	 * it to the first valid ITS, and let the HW do its magic.
>> +	 */
>> +	list_for_each_entry(its, &its_nodes, entry) {
>> +		if (!is_v4_1(its))
>> +			continue;
>> +
>> +		its_send_invdb(its, vpe);
>> +		break;
>> +	}
>
> Maybe use find_4_1_its() helper instead?

Yes, good point. I've moved it up in the series, and it is now added
to this patch.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...