Re: [RFC net-next Patch v2 4/4] net: bridge: mrp: switchdev: Add HW offload

From: Andrew Lunn <andrew@lunn.ch>
To: Horatiu Vultur <horatiu.vultur@microchip.com>
Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	bridge@lists.linux-foundation.org, davem@davemloft.net,
	roopa@cumulusnetworks.com, nikolay@cumulusnetworks.com,
	jakub.kicinski@netronome.com, vivien.didelot@gmail.com,
	olteanv@gmail.com, anirudh.venkataramanan@intel.com,
	dsahern@gmail.com, jiri@resnulli.us, ivecera@redhat.com,
	UNGLinuxDriver@microchip.com
Subject: Re: [RFC net-next Patch v2 4/4] net: bridge: mrp: switchdev: Add HW offload
Date: Mon, 13 Jan 2020 15:00:53 +0100	[thread overview]
Message-ID: <20200113140053.GE11788@lunn.ch> (raw)
In-Reply-To: <20200113124620.18657-5-horatiu.vultur@microchip.com>

On Mon, Jan 13, 2020 at 01:46:20PM +0100, Horatiu Vultur wrote:
> +#ifdef CONFIG_BRIDGE_MRP
> +/* SWITCHDEV_OBJ_ID_PORT_MRP */
> +struct switchdev_obj_port_mrp {
> +	struct switchdev_obj obj;
> +	struct net_device *port;
> +	u32 ring_nr;
> +};
> +
> +#define SWITCHDEV_OBJ_PORT_MRP(OBJ) \
> +	container_of((OBJ), struct switchdev_obj_port_mrp, obj)
> +
> +/* SWITCHDEV_OBJ_ID_RING_TEST_MRP */
> +struct switchdev_obj_ring_test_mrp {
> +	struct switchdev_obj obj;
> +	/* The value is in us and a value of 0 represents to stop */
> +	u32 interval;
> +	u8 max;
> +	u32 ring_nr;
> +};
> +
> +#define SWITCHDEV_OBJ_RING_TEST_MRP(OBJ) \
> +	container_of((OBJ), struct switchdev_obj_ring_test_mrp, obj)
> +
> +/* SWITCHDEV_OBJ_ID_RING_ROLE_MRP */
> +struct switchdev_obj_ring_role_mrp {
> +	struct switchdev_obj obj;
> +	u8 ring_role;
> +	u32 ring_nr;
> +};

Hi Horatiu

The structures above should give me enough information to build this,
correct?

Ethernet II, Src: 7a:8b:b1:35:96:e1 (7a:8b:b1:35:96:e1), Dst: Iec_00:00:01 (01:15:4e:00:00:01)
    Destination: Iec_00:00:01 (01:15:4e:00:00:01)
    Source: 7a:8b:b1:35:96:e1 (7a:8b:b1:35:96:e1)
    Type: MRP (0x88e3)
PROFINET MRP MRP_Test, MRP_Common, MRP_End
    MRP_Version: 1
    MRP_TLVHeader.Type: MRP_Test (0x02)
        MRP_TLVHeader.Type: MRP_Test (0x02)
        MRP_TLVHeader.Length: 18
        MRP_Prio: 0x1f40 High priorities
        MRP_SA: 7a:8b:b1:35:96:e1 (7a:8b:b1:35:96:e1)
        MRP_PortRole: Primary ring port (0x0000)
        MRP_RingState: Ring closed (0x0001)
        MRP_Transition: 0x0001
        MRP_TimeStamp [ms]: 0x000cf574             <---------- Updated automatic
    MRP_TLVHeader.Type: MRP_Common (0x01)
        MRP_TLVHeader.Type: MRP_Common (0x01)
        MRP_TLVHeader.Length: 18
        MRP_SequenceID: 0x00e9                     <---------- Updated automatic
        MRP_DomainUUID: ffffffff-ffff-ffff-ffff-ffffffffffff
    MRP_TLVHeader.Type: MRP_End (0x00)
        MRP_TLVHeader.Type: MRP_End (0x00)
        MRP_TLVHeader.Length: 0

There are a couple of fields i don't see. MRP_SA, MRP_Transition.

What are max and ring_nr used for?

Do you need to set the first value MRP_SequenceID uses? Often, in
order to detect a reset, a random value is used to initialise the
sequence number. Also, does the time stamp need initializing?

Thanks
	Andrew