From mboxrd@z Thu Jan 1 00:00:00 1970 From: Suman Anna Subject: Re: dra7xx pci driver broken on dra7xx-evm Date: Thu, 7 Jan 2016 15:26:18 -0600 Message-ID: <568ED7FA.4000508@ti.com> References: <20160106214518.GA6106@localhost.localdomain> <568DF4FE.5010704@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <568DF4FE.5010704@ti.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Kishon Vijay Abraham I , Richard Cochran , linux-arm-kernel@lists.infradead.org Cc: Bjorn Helgaas , Tero Kristo , Tony Lindgren , "linux-omap@vger.kernel.org" , "Murphy, Dan" List-Id: linux-omap@vger.kernel.org On 01/06/2016 11:17 PM, Kishon Vijay Abraham I wrote: > Hi, + Tero, Tony and linux-omap > > On Thursday 07 January 2016 03:15 AM, Richard Cochran wrote: >> >> The dra7xx-evm box freezes hard at the very first PCI bus access, the >> call to in dra7xx_pcie_readl() in dra7xx_pcie_probe(). >> >> The out-of-tree 3.14.53 TI driver performs a reset via platform data, >> calling omap_device_assert_hardreset() by hook and crook. Yeah, this is the only feasible way and not break multi-arch atm until a reset framework is in place. We have couple of drivers (omap_iommu and wkup_m3_rproc) following this approach. >> >> Adding the reset into the mainline driver cures the freeze. >> >> Question: How on earth is this driver supposed to work? > > It doesn't work out of the box in mainline. (Every time I post a PCI patch, I > add the pdata-quirks mechanism to test it). The pdata-quirks mechanism used in > TI tree is not an upstream-able solution. Something like this [1] was done for > performing reset. Not sure the latest state of that. Dan? Suman? Yeah, [1] is very old, and it doesn't deal with the hwmod integration for pm_runtime API usage. Tero has posted another revamped series [2] with hwmod integration, and it needs to be refreshed with few additional patches and fixes. It will probably take couple of releases before it hits mainline. So, I guess it is then a question of picking up the pdata quirks solution for interim to get the driver functional until the reset framework hits mainline, or mark the driver as broken. regards Suman > > [1] -> https://patches.linaro.org/33797/ [2] http://marc.info/?l=linux-omap&m=144310496514782&w=2