From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martyn Welch Subject: Re: [PATCH] STAGING: Comedi: Build only on arches providing PAGE_KERNEL_NOCACHE Date: Thu, 23 Jun 2011 12:53:36 +0100 Message-ID: <4E032940.5010205@ge.com> References: <20110623114536.GA14011@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20110623114536.GA14011@linux-mips.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: devel-bounces@linuxdriverproject.org Errors-To: devel-bounces@linuxdriverproject.org To: Ralf Baechle Cc: devel@driverdev.osuosl.org, linux-m32r-ja@ml.linux-m32r.org, linux-m32r@ml.linux-m32r.org, Paul Mundt , linux-sh@vger.kernel.org, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Chris Metcalf , David Howells , linux-am33-list@redhat.com, "H. Peter Anvin" , Thomas Gleixner , linux-arch@vger.kernel.org, Ingo Molnar , x86@kernel.org List-Id: linux-arch.vger.kernel.org T24gMjMvMDYvMTEgMTI6NDUsIFJhbGYgQmFlY2hsZSB3cm90ZToKPiBPbiBhcmNoaXRlY3R1cmVz IHRoYXQgZG9uJ3QgZGVmaW5lIFBBR0VfS0VSTkVMX05PQ0FDSEUsIHRoZSBDb21lZGkgZHJpdmVy IHR1cm5zCj4gaW50byB0cmFnZWR5Ogo+IAo+ICAgQ0MgW01dICBkcml2ZXJzL3N0YWdpbmcvY29t ZWRpL2RyaXZlcnMubwo+IGRyaXZlcnMvc3RhZ2luZy9jb21lZGkvZHJpdmVycy5jOiBJbiBmdW5j dGlvbiDigJhjb21lZGlfYnVmX2FsbG9j4oCZOgo+IGRyaXZlcnMvc3RhZ2luZy9jb21lZGkvZHJp dmVycy5jOjUwNTo0MTogZXJyb3I6IOKAmFBBR0VfS0VSTkVMX05PQ0FDSEXigJkgdW5kZWNsYXJl ZCAoZmlyc3QgdXNlIGluIHRoaXMgZnVuY3Rpb24pCj4gZHJpdmVycy9zdGFnaW5nL2NvbWVkaS9k cml2ZXJzLmM6NTA1OjQxOiBub3RlOiBlYWNoIHVuZGVjbGFyZWQgaWRlbnRpZmllciBpcyByZXAg b3J0ZWQgb25seSBvbmNlIGZvciBlYWNoIGZ1bmN0aW9uIGl0IGFwcGVhcnMgaW4KPiBtYWtlWzNd OiAqKiogW2RyaXZlcnMvc3RhZ2luZy9jb21lZGkvZHJpdmVycy5vXSBFcnJvciAxCj4gCj4gUmVz dHJpY3QgdGhlIGRyaXZlciB0byBvbmx5IHRob3NlIGFyY2hpdGVjdHVyZXMgdGhhdCBkZWZpbmUg UEFHRV9LRVJORUxfTk9DQUNIRS4KPiAKPiBQQUdFX0tFUk5FTF9OT0NBQ0hFIGlzIGEga2x1ZGdl IC0gc29tZSBzeXN0ZW0gYXJjaGl0ZWN0dXJlcyBzdWNoIGFzIFNHSSBJUDI3Cj4gYXJlIGV2ZW4g dWFibGUgdG8gb2ZmZXIgdW5jYWNoZWQgb3BlcmF0aW9uIC0gYXQgbGVhc3QgaW4gdGhlIHdheSBh biB1bndpdHRpbmcKPiBkcml2ZXIgbWlnaHQgYXNzdW1lLiAgSSBoYXZlbid0IGxvb2tlZCBpbiBk ZXRhaWxzIGhvdyB0aGUgZHJpdmVyIGlzIHVzaW5nCj4gdGhlIGFyZWEgdm1hcGVkIHdpdGggUEFH RV9LRVJORUxfTk9DQUNIRSBidXQgbWF5YmUgZG9pbmcgaXQgWEZTLXN0eWxlIHVzaW5nCj4gY2Fj aGVkIG1lbW9yeSBhbmQgdGhlIGZsdXNoX2tlcm5lbF92bWFwX3JhbmdlIC8gaW52YWxpZGF0ZV9r ZXJuZWxfdm1hcF9yYW5nZQo+IEFQSXMgaW4gY29uanVuY3Rpb24gd2l0aCB0aGUgRE1BIEFQSSBp cyBhIHByYWN0aWNhbCBhbHRlcm5hdGl2ZS4KPiAKPiBTaWduZWQtb2ZmLWJ5OiBSYWxmIEJhZWNo bGUgPHJhbGZAbGludXgtbWlwcy5vcmc+Cj4gCj4gIGRyaXZlcnMvc3RhZ2luZy9jb21lZGkvS2Nv bmZpZyB8ICAgIDEgKwo+ICAxIGZpbGVzIGNoYW5nZWQsIDEgaW5zZXJ0aW9ucygrKSwgMCBkZWxl dGlvbnMoLSkKPiAKPiBkaWZmIC0tZ2l0IGEvZHJpdmVycy9zdGFnaW5nL2NvbWVkaS9LY29uZmln IGIvZHJpdmVycy9zdGFnaW5nL2NvbWVkaS9LY29uZmlnCj4gaW5kZXggMTUwMmQ4MC4uYmNjZGMx MiAxMDA2NDQKPiAtLS0gYS9kcml2ZXJzL3N0YWdpbmcvY29tZWRpL0tjb25maWcKPiArKysgYi9k cml2ZXJzL3N0YWdpbmcvY29tZWRpL0tjb25maWcKPiBAQCAtMiw2ICsyLDcgQEAgY29uZmlnIENP TUVESQo+ICAJdHJpc3RhdGUgIkRhdGEgYWNxdWlzaXRpb24gc3VwcG9ydCAoY29tZWRpKSIKPiAg CWRlZmF1bHQgTgo+ICAJZGVwZW5kcyBvbiBtCj4gKwlkZXBlbmRzIG9uIEJST0tFTiB8fCBGUlYg fHwgTTMyUiB8fCBNTjEwMzAwIHx8IFNVUEVSSCB8fCBUSUxFIHx8IFg4NgoKSSdtIHN1cmUgSSBn b3QgY29tZWRpIHRvIGNvbXBpbGUgb24gYSAzMi1iaXQgUFBDIGJvYXJkIG5vdCB0aGF0IGxvbmcg YWdvLiBIYXMKc29tZXRoaW5nIGNoYW5nZWQsIG9yIGlzIHRoaXMganVzdCBub3QgYW4gZXhoYXVz dGl2ZSBsaXN0PwoKPiAgCS0tLWhlbHAtLS0KPiAgCSAgRW5hYmxlIHN1cHBvcnQgYSB3aWRlIHJh bmdlIG9mIGRhdGEgYWNxdWlzaXRpb24gZGV2aWNlcwo+ICAJICBmb3IgTGludXguCj4gX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KPiBkZXZlbCBtYWlsaW5n IGxpc3QKPiBkZXZlbEBsaW51eGRyaXZlcnByb2plY3Qub3JnCj4gaHR0cDovL2RyaXZlcmRldi5s aW51eGRyaXZlcnByb2plY3Qub3JnL21haWxtYW4vbGlzdGluZm8vZGV2ZWwKCgotLSAKTWFydHlu IFdlbGNoIChQcmluY2lwYWwgU29mdHdhcmUgRW5naW5lZXIpIHwgUmVnaXN0ZXJlZCBpbiBFbmds YW5kIGFuZApHRSBJbnRlbGxpZ2VudCBQbGF0Zm9ybXMgICAgICAgICAgICAgICAgICAgfCBXYWxl cyAoMzgyODY0MikgYXQgMTAwClQgKzQ0KDApMTI3MzIyNzQ4ICAgICAgICAgICAgICAgICAgICAg ICAgICB8IEJhcmJpcm9sbGkgU3F1YXJlLCBNYW5jaGVzdGVyLApFIG1hcnR5bi53ZWxjaEBnZS5j b20gICAgICAgICAgICAgICAgICAgICAgfCBNMiAzQUIgIFZBVDpHQiA5Mjc1NTkxODkKX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZGV2ZWwgbWFpbGluZyBs aXN0CmRldmVsQGxpbnV4ZHJpdmVycHJvamVjdC5vcmcKaHR0cDovL2RyaXZlcmRldi5saW51eGRy aXZlcnByb2plY3Qub3JnL21haWxtYW4vbGlzdGluZm8vZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from exprod5og101.obsmtp.com ([64.18.0.141]:53719 "EHLO exprod5og101.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755812Ab1FWL6p (ORCPT ); Thu, 23 Jun 2011 07:58:45 -0400 Message-ID: <4E032940.5010205@ge.com> Date: Thu, 23 Jun 2011 12:53:36 +0100 From: Martyn Welch MIME-Version: 1.0 Subject: Re: [PATCH] STAGING: Comedi: Build only on arches providing PAGE_KERNEL_NOCACHE References: <20110623114536.GA14011@linux-mips.org> In-Reply-To: <20110623114536.GA14011@linux-mips.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Ralf Baechle Cc: Greg Kroah-Hartman , devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, David Howells , linux-m32r@ml.linux-m32r.org, linux-m32r-ja@ml.linux-m32r.org, linux-am33-list@redhat.com, Paul Mundt , linux-sh@vger.kernel.org, Chris Metcalf , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-arch@vger.kernel.org Message-ID: <20110623115336.Gmv7Fn2d1GCx3sJGiY4hGPARibSvKMeQ6ZaaaleEBnQ@z> On 23/06/11 12:45, Ralf Baechle wrote: > On architectures that don't define PAGE_KERNEL_NOCACHE, the Comedi driver turns > into tragedy: > > CC [M] drivers/staging/comedi/drivers.o > drivers/staging/comedi/drivers.c: In function ‘comedi_buf_alloc’: > drivers/staging/comedi/drivers.c:505:41: error: ‘PAGE_KERNEL_NOCACHE’ undeclared (first use in this function) > drivers/staging/comedi/drivers.c:505:41: note: each undeclared identifier is rep orted only once for each function it appears in > make[3]: *** [drivers/staging/comedi/drivers.o] Error 1 > > Restrict the driver to only those architectures that define PAGE_KERNEL_NOCACHE. > > PAGE_KERNEL_NOCACHE is a kludge - some system architectures such as SGI IP27 > are even uable to offer uncached operation - at least in the way an unwitting > driver might assume. I haven't looked in details how the driver is using > the area vmaped with PAGE_KERNEL_NOCACHE but maybe doing it XFS-style using > cached memory and the flush_kernel_vmap_range / invalidate_kernel_vmap_range > APIs in conjunction with the DMA API is a practical alternative. > > Signed-off-by: Ralf Baechle > > drivers/staging/comedi/Kconfig | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig > index 1502d80..bccdc12 100644 > --- a/drivers/staging/comedi/Kconfig > +++ b/drivers/staging/comedi/Kconfig > @@ -2,6 +2,7 @@ config COMEDI > tristate "Data acquisition support (comedi)" > default N > depends on m > + depends on BROKEN || FRV || M32R || MN10300 || SUPERH || TILE || X86 I'm sure I got comedi to compile on a 32-bit PPC board not that long ago. Has something changed, or is this just not an exhaustive list? > ---help--- > Enable support a wide range of data acquisition devices > for Linux. > _______________________________________________ > devel mailing list > devel@linuxdriverproject.org > http://driverdev.linuxdriverproject.org/mailman/listinfo/devel -- Martyn Welch (Principal Software Engineer) | Registered in England and GE Intelligent Platforms | Wales (3828642) at 100 T +44(0)127322748 | Barbirolli Square, Manchester, E martyn.welch@ge.com | M2 3AB VAT:GB 927559189