Messages in this thread | | | Date | Fri, 13 Jan 2023 14:16:03 +0000 | From | "Russell King (Oracle)" <> | Subject | Re: [PATCH v4 1/3] dsa: marvell: Provide per device information about max frame size |
| |
On Fri, Jan 06, 2023 at 11:16:49AM +0100, Lukasz Majewski wrote: > Different Marvell DSA switches support different size of max frame > bytes to be sent. This value corresponds to the memory allocated > in switch to store single frame. > > For example mv88e6185 supports max 1632 bytes, which is now in-driver > standard value. On the other hand - mv88e6250 supports 2048 bytes. > To be more interresting - devices supporting jumbo frames - use yet > another value (10240 bytes) > > As this value is internal and may be different for each switch IC, > new entry in struct mv88e6xxx_info has been added to store it. > > This commit doesn't change the code functionality - it just provides > the max frame size value explicitly - up till now it has been > assigned depending on the callback provided by the IC driver > (e.g. .set_max_frame_size, .port_set_jumbo_size).
I don't think this patch is correct.
One of the things that mv88e6xxx_setup_port() does when initialising each port is:
if (chip->info->ops->port_set_jumbo_size) { err = chip->info->ops->port_set_jumbo_size(chip, port, 10218); if (err) return err; }
There is one implementation of this, which is mv88e6165_port_set_jumbo_size() and that has the effect of setting port register 8 to the largest size. So any chip that supports the port_set_jumbo_size() method will be programmed on initialisation to support this larger size.
However, you seem to be listing e.g. the 88e6190 (if I'm interpreting the horrid mv88e6xxx_table changes correctly) as having a maximum frame size of 1522, but it implements this method, supports 10240, and thus is programmed to support frames of that size rather than 1522.
-- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
| |