On Sun, May 21, 2017 at 09:55:55AM +0000, Bernat, Yehezkel wrote: > > > > -----Original Message----- > > From: Levy, Amir (Jer) > > Sent: Sunday, May 21, 2017 11:07 > > To: Mika Westerberg <mika.westerb...@linux.intel.com>; Lukas Wunner > > <lu...@wunner.de> > > Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>; Andreas Noever > > <andreas.noe...@gmail.com>; Jamet, Michael <michael.ja...@intel.com>; > > Bernat, Yehezkel <yehezkel.ber...@intel.com>; Andy Lutomirski > > <l...@kernel.org>; mario.limoncie...@dell.com; > > jared.doming...@dell.com; Andy Shevchenko > > <andriy.shevche...@linux.intel.com>; linux-kernel@vger.kernel.org > > Subject: RE: [PATCH 18/24] thunderbolt: Store Thunderbolt generation in the > > switch structure > > > > On Sun, May 21 2017, 11:00 AM, Mika Westerberg wrote: > > > On Sun, May 21, 2017 at 10:40:41AM +0300, Mika Westerberg wrote: > > > > On Sun, May 21, 2017 at 07:35:21AM +0200, Lukas Wunner wrote: > > > > > On Sun, May 21, 2017 at 05:29:47AM +0000, Levy, Amir (Jer) wrote: > > > > > > On Sun, May 21 2017, 07:47 AM, Lukas Wunner wrote: > > > > > > > On Thu, May 18, 2017 at 05:39:08PM +0300, Mika Westerberg wrote: > > > > > > > > + > > > > > > > > + default: > > > > > > > > + sw->generation = 1; > > > > > > > > + break; > > > > > > > > > > > > > > If someone adds an entry for, say, a new TB3 controller to > > > > > > > nhi_ids[] but forgets to update this function, the controller > > > > > > > is assigned the wrong generation number. It might be better > > > > > > > to make TB3 the default and list each TB1 controller instead > > > > > > > since it's less likely for Intel to introduce an older gen chip. > > > > > > > > > > > > > > Generally I think it's problematic to require that multiple > > > > > > > files are touched whenever a new controller is added. Isn't > > > > > > > the generation number or link speed (10/20/40) stored in some > > > > > > > register in PCI config space (VSEC 0x1234) or TB config space? > > > > > > > > > > > > How about setting information, that isn't available from PCI, in > > > > > > pci_device_id.driver_data when initializing nhi_ids[]? > > > > > > > > > > Right, that would also be possible, though reading the generation > > > > > number from a register would be more elegant, if such a register > > > > > exists. > > > > > > > > I don't think there is such register but I can put this information > > > > to the driver_data instead. > > > > > > Actually these are Thunderbolt switch IDs, not NHI PCI IDs so I don't > > > think driver_data is the right place after all. So if no objections, > > > I'll update the function to default to TBT3 but keep the switch case > > > and add the TBT1 IDs + Win Ridge there. > > > > There is correlation between switch ID to NHI ID. > > I'm not sure defaulting to TBT3 is a good idea. ICM message format can > be changed, DMA port can be different, nothing guaranties correct > operation of the driver with newer unknown controllers.
Fair enough :) Then we just need to remember to update the function here as new generations get added and tested. I suppose you don't know either if we could use the revision or similar field in the switch config space to determine generation somehow?