From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey.Brodkin@synopsys.com (Alexey Brodkin) Date: Tue, 5 Dec 2017 09:32:23 +0000 Subject: etnaviv: PHYS_OFFSET usage In-Reply-To: <1510768580.2835.15.camel@pengutronix.de> References: <1510763053.29843.64.camel@synopsys.com> <1510764243.2835.13.camel@pengutronix.de> <1510767395.29843.83.camel@synopsys.com> <1510768580.2835.15.camel@pengutronix.de> List-ID: Message-ID: <1512466342.4977.77.camel@synopsys.com> To: linux-snps-arc@lists.infradead.org Hi Lucas, On Wed, 2017-11-15@18:56 +0100, Lucas Stach wrote: > Am Mittwoch, den 15.11.2017, 17:36 +0000 schrieb Alexey Brodkin: [snip] > I'm not keen on having a private memory region for the GPU. Normally we > just use the shared system CMA memory region (and we will point the > linear memory window there on MC2.0 GPUs), which has the added benefit > that we can map the contiguous framebuffers allocated by another device > through the linear window, which is a crucial performance optimization > for the MMUv1 GPUs. > > The only time where we really need to know the start of RAM is on MC1.0 > GPUs which have a hardware bug in the TS unit, so we try to avoid > moving the linear window at all to work around that. In that case the > PHYS_OFFSET check is really there to avoid the situation where the > linear window would not allow any RAM to be reached at all. Then we > need to move the window, but disable any TS functionality, impacting > performance a lot. Thanks a lot fro explanation! > As MC1.0 GPUs are hopefully on the way out with new designs using MC2.0 > this shouldn't be much of a problem going forward. Maybe we can even > simply solve this issue by just dropping the check if PHYS_OFFSET isn't > defined. I guess something like that should work then: -------------------------------->8-------------------------------- diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index fc9a6a83dfc7..5ad191a605e2 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -678,6 +678,7 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu) ????????????????goto fail; ????????} ? +#ifdef PHYS_OFFSET ????????/* ?????????* Set the GPU linear window to be at the end of the DMA window, where ?????????* the CMA area is likely to reside. This ensures that we are able to @@ -699,6 +700,7 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu) ????????????????gpu->memory_base = PHYS_OFFSET; ????????????????gpu->identity.features &= ~chipFeatures_FAST_CLEAR; ????????} +#endif ? ????????ret = etnaviv_hw_reset(gpu); ????????if (ret) { -------------------------------->8-------------------------------- > At least I hope VeriSilicon didn't sell you a MC1.0 part at > this time... Given "chipMinorFeatures0_MC20" bit is set for us I would think that we indeed have MC2.0 in our chip. -Alexey From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Brodkin Subject: Re: etnaviv: PHYS_OFFSET usage Date: Tue, 5 Dec 2017 09:32:23 +0000 Message-ID: <1512466342.4977.77.camel@synopsys.com> References: <1510763053.29843.64.camel@synopsys.com> <1510764243.2835.13.camel@pengutronix.de> <1510767395.29843.83.camel@synopsys.com> <1510768580.2835.15.camel@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1510768580.2835.15.camel@pengutronix.de> Content-Language: en-US Content-ID: Sender: linux-kernel-owner@vger.kernel.org To: "l.stach@pengutronix.de" Cc: "christian.gmeiner@gmail.com" , "Vineet.Gupta1@synopsys.com" , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , "linux-snps-arc@lists.infradead.org" List-Id: dri-devel@lists.freedesktop.org SGkgTHVjYXMsDQoNCk9uIFdlZCwgMjAxNy0xMS0xNSBhdCAxODo1NiArMDEwMCwgTHVjYXMgU3Rh Y2ggd3JvdGU6DQo+IEFtIE1pdHR3b2NoLCBkZW4gMTUuMTEuMjAxNywgMTc6MzYgKzAwMDAgc2No cmllYiBBbGV4ZXkgQnJvZGtpbjoNCg0KW3NuaXBdDQoNCj4gSSdtIG5vdCBrZWVuIG9uIGhhdmlu ZyBhIHByaXZhdGUgbWVtb3J5IHJlZ2lvbiBmb3IgdGhlIEdQVS4gTm9ybWFsbHkgd2UNCj4ganVz dCB1c2UgdGhlIHNoYXJlZCBzeXN0ZW0gQ01BIG1lbW9yeSByZWdpb24gKGFuZCB3ZSB3aWxsIHBv aW50IHRoZQ0KPiBsaW5lYXIgbWVtb3J5IHdpbmRvdyB0aGVyZSBvbiBNQzIuMCBHUFVzKSwgd2hp Y2ggaGFzIHRoZSBhZGRlZCBiZW5lZml0DQo+IHRoYXQgd2UgY2FuIG1hcCB0aGUgY29udGlndW91 cyBmcmFtZWJ1ZmZlcnMgYWxsb2NhdGVkIGJ5IGFub3RoZXIgZGV2aWNlDQo+IHRocm91Z2ggdGhl IGxpbmVhciB3aW5kb3csIHdoaWNoIGlzIGEgY3J1Y2lhbCBwZXJmb3JtYW5jZSBvcHRpbWl6YXRp b24NCj4gZm9yIHRoZSBNTVV2MSBHUFVzLg0KPiANCj4gVGhlIG9ubHkgdGltZSB3aGVyZSB3ZSBy ZWFsbHkgbmVlZCB0byBrbm93IHRoZSBzdGFydCBvZiBSQU0gaXMgb24gTUMxLjANCj4gR1BVcyB3 aGljaCBoYXZlIGEgaGFyZHdhcmUgYnVnIGluIHRoZSBUUyB1bml0LCBzbyB3ZSB0cnkgdG8gYXZv aWQNCj4gbW92aW5nIHRoZSBsaW5lYXIgd2luZG93IGF0IGFsbCB0byB3b3JrIGFyb3VuZCB0aGF0 LiBJbiB0aGF0IGNhc2UgdGhlDQo+IFBIWVNfT0ZGU0VUIGNoZWNrIGlzIHJlYWxseSB0aGVyZSB0 byBhdm9pZCB0aGUgc2l0dWF0aW9uIHdoZXJlIHRoZQ0KPiBsaW5lYXIgd2luZG93IHdvdWxkIG5v dCBhbGxvdyBhbnkgUkFNIHRvIGJlIHJlYWNoZWQgYXQgYWxsLiBUaGVuIHdlDQo+IG5lZWQgdG8g bW92ZSB0aGUgd2luZG93LCBidXQgZGlzYWJsZSBhbnkgVFMgZnVuY3Rpb25hbGl0eSwgaW1wYWN0 aW5nDQo+IHBlcmZvcm1hbmNlIGEgbG90Lg0KDQpUaGFua3MgYSBsb3QgZnJvIGV4cGxhbmF0aW9u IQ0KDQo+IEFzIE1DMS4wIEdQVXMgYXJlIGhvcGVmdWxseSBvbiB0aGUgd2F5IG91dCB3aXRoIG5l dyBkZXNpZ25zIHVzaW5nIE1DMi4wDQo+IHRoaXMgc2hvdWxkbid0IGJlIG11Y2ggb2YgYSBwcm9i bGVtIGdvaW5nIGZvcndhcmQuIE1heWJlIHdlIGNhbiBldmVuDQo+IHNpbXBseSBzb2x2ZSB0aGlz IGlzc3VlIGJ5IGp1c3QgZHJvcHBpbmcgdGhlIGNoZWNrIGlmIFBIWVNfT0ZGU0VUIGlzbid0DQo+ IGRlZmluZWQuDQoNCkkgZ3Vlc3Mgc29tZXRoaW5nIGxpa2UgdGhhdCBzaG91bGQgd29yayB0aGVu Og0KLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0+OC0tLS0tLS0tLS0tLS0tLS0tLS0t LS0tLS0tLS0tLS0tDQpkaWZmIC0tZ2l0IGEvZHJpdmVycy9ncHUvZHJtL2V0bmF2aXYvZXRuYXZp dl9ncHUuYyBiL2RyaXZlcnMvZ3B1L2RybS9ldG5hdml2L2V0bmF2aXZfZ3B1LmMNCmluZGV4IGZj OWE2YTgzZGZjNy4uNWFkMTkxYTYwNWUyIDEwMDY0NA0KLS0tIGEvZHJpdmVycy9ncHUvZHJtL2V0 bmF2aXYvZXRuYXZpdl9ncHUuYw0KKysrIGIvZHJpdmVycy9ncHUvZHJtL2V0bmF2aXYvZXRuYXZp dl9ncHUuYw0KQEAgLTY3OCw2ICs2NzgsNyBAQCBpbnQgZXRuYXZpdl9ncHVfaW5pdChzdHJ1Y3Qg ZXRuYXZpdl9ncHUgKmdwdSkNCsKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKgZ290byBm YWlsOw0KwqDCoMKgwqDCoMKgwqDCoH0NCsKgDQorI2lmZGVmIFBIWVNfT0ZGU0VUDQrCoMKgwqDC oMKgwqDCoMKgLyoNCsKgwqDCoMKgwqDCoMKgwqDCoCogU2V0IHRoZSBHUFUgbGluZWFyIHdpbmRv dyB0byBiZSBhdCB0aGUgZW5kIG9mIHRoZSBETUEgd2luZG93LCB3aGVyZQ0KwqDCoMKgwqDCoMKg wqDCoMKgKiB0aGUgQ01BIGFyZWEgaXMgbGlrZWx5IHRvIHJlc2lkZS4gVGhpcyBlbnN1cmVzIHRo YXQgd2UgYXJlIGFibGUgdG8NCkBAIC02OTksNiArNzAwLDcgQEAgaW50IGV0bmF2aXZfZ3B1X2lu aXQoc3RydWN0IGV0bmF2aXZfZ3B1ICpncHUpDQrCoMKgwqDCoMKgwqDCoMKgwqDCoMKgwqDCoMKg wqDCoGdwdS0+bWVtb3J5X2Jhc2UgPSBQSFlTX09GRlNFVDsNCsKgwqDCoMKgwqDCoMKgwqDCoMKg wqDCoMKgwqDCoMKgZ3B1LT5pZGVudGl0eS5mZWF0dXJlcyAmPSB+Y2hpcEZlYXR1cmVzX0ZBU1Rf Q0xFQVI7DQrCoMKgwqDCoMKgwqDCoMKgfQ0KKyNlbmRpZg0KwqANCsKgwqDCoMKgwqDCoMKgwqBy ZXQgPSBldG5hdml2X2h3X3Jlc2V0KGdwdSk7DQrCoMKgwqDCoMKgwqDCoMKgaWYgKHJldCkgew0K LS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0+OC0tLS0tLS0tLS0tLS0tLS0tLS0tLS0t LS0tLS0tLS0tDQoNCj4gQXQgbGVhc3QgSSBob3BlIFZlcmlTaWxpY29uIGRpZG4ndCBzZWxsIHlv dSBhIE1DMS4wIHBhcnQgYXQNCj4gdGhpcyB0aW1lLi4uDQoNCkdpdmVuICJjaGlwTWlub3JGZWF0 dXJlczBfTUMyMCIgYml0IGlzIHNldCBmb3IgdXMgSSB3b3VsZCB0aGluayB0aGF0IHdlDQppbmRl ZWQgaGF2ZSBNQzIuMCBpbiBvdXIgY2hpcC4NCg0KLUFsZXhleQ==