From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis Chamberlain Date: Wed, 13 Nov 2019 18:45:05 +0000 Subject: Re: [PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64 Message-Id: <20191113184505.GW11244@42.do-not-panic.com> List-Id: References: <20191111192258.2234502-1-arnd@arndb.de> <20191112105507.GA7122@lst.de> <20191112140631.GA10922@lst.de> <20191112222423.GO11244@42.do-not-panic.com> <20191113072708.GA3213@lst.de> <20191113093154.GB32742@smile.fi.intel.com> In-Reply-To: <20191113093154.GB32742@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andy Shevchenko Cc: Linux Fbdev development list , linux-ia64@vger.kernel.org, Daniel Vetter , dri-devel , "H. Peter Anvin" , Lee Jones , Christoph Hellwig , X86 ML , Ingo Molnar , Tuowen Zhao , Fenghua Yu , Arnd Bergmann , Bartlomiej Zolnierkiewicz , "Luis R. Rodriguez" , Borislav Petkov , Thomas Gleixner , Mika Westerberg , Juergen Gross , Tony Luck , Linux Kernel Mailing List , AceLan Kao , Souptick Joarder , Roman Gilg On Wed, Nov 13, 2019 at 11:31:54AM +0200, Andy Shevchenko wrote: > On Wed, Nov 13, 2019 at 08:38:15AM +0100, Arnd Bergmann wrote: > > On Wed, Nov 13, 2019 at 8:27 AM Christoph Hellwig wrote: > > > > > > On Tue, Nov 12, 2019 at 10:24:23PM +0000, Luis Chamberlain wrote: > > > > I think this would be possible if we could flop ioremap_nocache() to UC > > > > instead of UC- on x86. Otherwise, I can't see how we can remove this by > > > > still not allowing direct MTRR calls. > > > > > > If everything goes well ioremap_nocache will be gone as of 5.5. > > > > As ioremap_nocache() just an alias for ioremap(), I suppose the idea would > > then be to make x86 ioremap be UC instead of UC-, again matching what the > > other architectures do already. > > I think it's right thing to do, i.e. assume that ioremap() always does strong > UC independently on MTRR settings. Agreed wholeheartedly. What are the blockers from making that happen? Do we have any left? Luis From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis Chamberlain Date: Wed, 13 Nov 2019 18:45:05 +0000 Subject: Re: [PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64 Message-Id: <20191113184505.GW11244@42.do-not-panic.com> List-Id: References: <20191111192258.2234502-1-arnd@arndb.de> <20191112105507.GA7122@lst.de> <20191112140631.GA10922@lst.de> <20191112222423.GO11244@42.do-not-panic.com> <20191113072708.GA3213@lst.de> <20191113093154.GB32742@smile.fi.intel.com> In-Reply-To: <20191113093154.GB32742@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andy Shevchenko Cc: Arnd Bergmann , Christoph Hellwig , Daniel Vetter , Juergen Gross , Tuowen Zhao , AceLan Kao , Mika Westerberg , Roman Gilg , Lee Jones , "Luis R. Rodriguez" , Bartlomiej Zolnierkiewicz , X86 ML , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , linux-ia64@vger.kernel.org, Tony Luck , Fenghua Yu , Maarten Lankhorst , Souptick Joarder , dri-devel , Linux Fbdev development list , Linux Kernel Mailing List On Wed, Nov 13, 2019 at 11:31:54AM +0200, Andy Shevchenko wrote: > On Wed, Nov 13, 2019 at 08:38:15AM +0100, Arnd Bergmann wrote: > > On Wed, Nov 13, 2019 at 8:27 AM Christoph Hellwig wrote: > > > > > > On Tue, Nov 12, 2019 at 10:24:23PM +0000, Luis Chamberlain wrote: > > > > I think this would be possible if we could flop ioremap_nocache() to UC > > > > instead of UC- on x86. Otherwise, I can't see how we can remove this by > > > > still not allowing direct MTRR calls. > > > > > > If everything goes well ioremap_nocache will be gone as of 5.5. > > > > As ioremap_nocache() just an alias for ioremap(), I suppose the idea would > > then be to make x86 ioremap be UC instead of UC-, again matching what the > > other architectures do already. > > I think it's right thing to do, i.e. assume that ioremap() always does strong > UC independently on MTRR settings. Agreed wholeheartedly. What are the blockers from making that happen? Do we have any left? Luis From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis Chamberlain Subject: Re: [PATCH] video: fbdev: atyfb: only use ioremap_uc() on i386 and ia64 Date: Wed, 13 Nov 2019 18:45:05 +0000 Message-ID: <20191113184505.GW11244@42.do-not-panic.com> References: <20191111192258.2234502-1-arnd@arndb.de> <20191112105507.GA7122@lst.de> <20191112140631.GA10922@lst.de> <20191112222423.GO11244@42.do-not-panic.com> <20191113072708.GA3213@lst.de> <20191113093154.GB32742@smile.fi.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail-pf1-f193.google.com (mail-pf1-f193.google.com [209.85.210.193]) by gabe.freedesktop.org (Postfix) with ESMTPS id E8A5F6EDFE for ; Wed, 13 Nov 2019 18:45:07 +0000 (UTC) Received: by mail-pf1-f193.google.com with SMTP id r4so2237620pfl.7 for ; Wed, 13 Nov 2019 10:45:07 -0800 (PST) Content-Disposition: inline In-Reply-To: <20191113093154.GB32742@smile.fi.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Andy Shevchenko Cc: Linux Fbdev development list , linux-ia64@vger.kernel.org, Daniel Vetter , dri-devel , "H. Peter Anvin" , Lee Jones , Christoph Hellwig , X86 ML , Ingo Molnar , Tuowen Zhao , Fenghua Yu , Arnd Bergmann , Bartlomiej Zolnierkiewicz , "Luis R. Rodriguez" , Borislav Petkov , Thomas Gleixner , Mika Westerberg , Juergen Gross , Tony Luck , Linux Kernel Mailing List , AceLan Kao , Souptick Joarder , Roman Gilg List-Id: dri-devel@lists.freedesktop.org T24gV2VkLCBOb3YgMTMsIDIwMTkgYXQgMTE6MzE6NTRBTSArMDIwMCwgQW5keSBTaGV2Y2hlbmtv IHdyb3RlOgo+IE9uIFdlZCwgTm92IDEzLCAyMDE5IGF0IDA4OjM4OjE1QU0gKzAxMDAsIEFybmQg QmVyZ21hbm4gd3JvdGU6Cj4gPiBPbiBXZWQsIE5vdiAxMywgMjAxOSBhdCA4OjI3IEFNIENocmlz dG9waCBIZWxsd2lnIDxoY2hAbHN0LmRlPiB3cm90ZToKPiA+ID4KPiA+ID4gT24gVHVlLCBOb3Yg MTIsIDIwMTkgYXQgMTA6MjQ6MjNQTSArMDAwMCwgTHVpcyBDaGFtYmVybGFpbiB3cm90ZToKPiA+ ID4gPiBJIHRoaW5rIHRoaXMgd291bGQgYmUgcG9zc2libGUgaWYgd2UgY291bGQgZmxvcCBpb3Jl bWFwX25vY2FjaGUoKSB0byBVQwo+ID4gPiA+IGluc3RlYWQgb2YgVUMtIG9uIHg4Ni4gT3RoZXJ3 aXNlLCBJIGNhbid0IHNlZSBob3cgd2UgY2FuIHJlbW92ZSB0aGlzIGJ5Cj4gPiA+ID4gc3RpbGwg bm90IGFsbG93aW5nIGRpcmVjdCBNVFJSIGNhbGxzLgo+ID4gPgo+ID4gPiBJZiBldmVyeXRoaW5n IGdvZXMgd2VsbCBpb3JlbWFwX25vY2FjaGUgd2lsbCBiZSBnb25lIGFzIG9mIDUuNS4KPiA+IAo+ ID4gQXMgaW9yZW1hcF9ub2NhY2hlKCkganVzdCBhbiBhbGlhcyBmb3IgaW9yZW1hcCgpLCBJIHN1 cHBvc2UgdGhlIGlkZWEgd291bGQKPiA+IHRoZW4gYmUgdG8gbWFrZSB4ODYgaW9yZW1hcCBiZSBV QyBpbnN0ZWFkIG9mIFVDLSwgYWdhaW4gbWF0Y2hpbmcgd2hhdCB0aGUKPiA+IG90aGVyIGFyY2hp dGVjdHVyZXMgZG8gYWxyZWFkeS4KPiAKPiBJIHRoaW5rIGl0J3MgcmlnaHQgdGhpbmcgdG8gZG8s IGkuZS4gYXNzdW1lIHRoYXQgaW9yZW1hcCgpIGFsd2F5cyBkb2VzIHN0cm9uZwo+IFVDIGluZGVw ZW5kZW50bHkgb24gTVRSUiBzZXR0aW5ncy4KCkFncmVlZCB3aG9sZWhlYXJ0ZWRseS4gV2hhdCBh cmUgdGhlIGJsb2NrZXJzIGZyb20gbWFraW5nIHRoYXQgaGFwcGVuPyBEbwp3ZSBoYXZlIGFueSBs ZWZ0PwoKICBMdWlzCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9y ZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZl bA==