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;
Date:   Sat, 3 Aug 2019 16:14:01 +0200
From:   Lukas Wunner <lukas@wunner.de>
To:     Mika Westerberg <mika.westerberg@linux.intel.com>
Cc:     linux-kernel@vger.kernel.org,
        Andreas Noever <andreas.noever@gmail.com>,
        Michael Jamet <michael.jamet@intel.com>,
        Yehezkel Bernat <YehezkelShB@gmail.com>
Subject: Re: [PATCH 4/8] thunderbolt: Do not fail adding switch if some port
 is not implemented
Message-ID: <20190803141401.bmjo7u723p4wxtqb@wunner.de>
References: <20190705095800.43534-1-mika.westerberg@linux.intel.com>
 <20190705095800.43534-5-mika.westerberg@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20190705095800.43534-5-mika.westerberg@linux.intel.com>
User-Agent: NeoMutt/20170113 (1.7.2)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, Jul 05, 2019 at 12:57:56PM +0300, Mika Westerberg wrote:
> There are two ways to mark a port as unimplemented. Typical way is to
> return port type as TB_TYPE_INACTIVE when its config space is read.
> Alternatively if the port is not physically present (such as ports 10
> and 11 in ICL) reading from port config space returns
> TB_CFG_ERROR_INVALID_CONFIG_SPACE instead. Currently the driver bails
> out from adding the switch if it receives any error during port
> inititialization which is wrong.
> 
> Handle this properly and just leave the port as TB_TYPE_INACTIVE before
> continuing to the next port.

Your patch may also cause this snippet in eeprom.c to become obsolete:

		/* Port 5 is inaccessible on this gen 1 controller */
		if (sw->config.device_id == PCI_DEVICE_ID_INTEL_LIGHT_RIDGE)
			sw->ports[5].disabled = true;

To verify this hypothesis, one needs to comment out the call to
tb_drom_copy_efi() as well as the above-quoted snippet and boot
on a Mac with Light Ridge.  The driver should hit an error without
your patch and it may work correctly with your patch.

Thanks,

Lukas