-------- Original-Nachricht -------- > Datum: Thu, 19 Apr 2012 14:41:16 +0200 > Von: "Michel Dänzer" <mic...@daenzer.net> > An: Gerhard Pircher <gerhard_pirc...@gmx.net> > CC: linuxppc-dev@lists.ozlabs.org, sch...@linux-m68k.org, > ojordan12...@hotmail.co.uk > Betreff: Re: PowerPC radeon KMS - is it possible?
> On Don, 2012-04-19 at 13:48 +0200, Gerhard Pircher wrote: > > > Von: "Michel Dänzer" <mic...@daenzer.net> > > > On Mit, 2012-04-18 at 18:23 +0200, Gerhard Pircher wrote: > > > > > Von: "Michel Dänzer" <mic...@daenzer.net> > > > > > On Mit, 2012-04-18 at 17:49 +0200, Gerhard Pircher wrote: > > > > > > > > > > > > That may be a stupid question, but is it allowed (for a DRM > > > > > > client or whatever does the mapping) to change the content of > > > > > > a page mapped into the AGP GART or is it necessary to > > > > > > explicitly unmap the page, change its content and map it again? > > > > > > > > > > The former. > > > > I know that the uninorth AGPGART driver does a cache flushing for > > > > newly mapped pages, but is there any code in the driver that > > > > handles the former case (or isn't this necessary on PPC Macs)? > > > > > > If by 'former case' you mean userspace modifying memory mapped into > > > the AGP GART, then no, this generally doesn't require special > > > treatment on PowerMacs. (Ignoring the potential issue mentioned by > > > Ben in this thread) > > I guess you refer to the ordering issue here. > > Yeah. > > > The "former case" is an explanation, why I see data corruption with my > > AGPGART driver (more or less a copy of the uninorth driver) on my > > non-coherent platform. There are no cache flushes done for writes to > > already mapped pages. > > As I said, the radeon driver always maps AGP memory uncacheable for the > CPU, so no such CPU cache flushes should be necessary. I know. We also discussed this topic over two years ago. :-) What I didn't understand yet is how this uncacheable memory is allocated (well, I never took the time to look at this again). The functions in ttm_page_alloc.c seem to allocate normal cacheable memory and try to set the page flags with set_pages_array_uc(), which is more or less a no-op on powerpc. ttm_page_alloc_dma.c on the other side is only used with SWIOTLB!? > > I tested this with radeon.test=1, but I'm not even sure if this code > > changes already mapped pages [...] > > It does. radeon_bo_pin(..., RADEON_GEM_DOMAIN_GTT, ...) binds the buffer > memory into the AGP GART, and the test only maps it to the CPU after > that. Could it be that the memory is finally mapped uncacheable by radeon_bo_kmap()/ ttm_bo_kmap()/..some other TTM functions../vmap()? > I take it the test fails for you? How exactly? I didn't work on the driver for a long time. It looks like I did the last tests with a 2.6.39 kernel, where I changed the radeon test routine to not stop on a failed copy. This way I could check for a pattern in the failed copies. Here is an excerpt of the 2.6.39 kernel log. IIRC the testing code changed in the meantime so I guess it would make sense to repeat it with a newer kernel version. [ 5.185619] calling agp_init+0x0/0x5c @ 1 [ 5.189816] Linux agpgart interface v0.103 [ 5.193993] initcall agp_init+0x0/0x5c returned 0 after 4076 usecs [ 5.200359] calling agp_articias_init+0x0/0x58 @ 1 [ 5.205411] agpgart-articias 0000:00:00.0: MAI Logic Articia S chipset [ 5.213555] agpgart-articias 0000:00:00.0: configuring for size idx: 6 [ 5.220996] agpgart-articias 0000:00:00.0: AGP aperture is 128M @ 0xc0000000 [ 5.228557] initcall agp_articias_init+0x0/0x58 returned 0 after 22629 usecs [ 5.235791] calling drm_core_init+0x0/0x16c @ 1 [ 5.240839] [drm] Initialized drm 1.1.0 20060810 [ 5.245623] initcall drm_core_init+0x0/0x16c returned 0 after 4937 usecs [ 5.252510] calling ttm_init+0x0/0x8c @ 1 [ 5.256908] initcall ttm_init+0x0/0x8c returned 0 after 197 usecs [ 5.263172] calling radeon_init+0x0/0x11c @ 1 [ 5.267731] [drm] radeon kernel modesetting enabled. [ 5.274683] [drm] initializing kernel modesetting (RV280 0x1002:0x5960). [ 5.281657] [drm] register mmio base: 0x88000000 [ 5.286397] [drm] register mmio size: 65536 [ 5.327510] [drm] AGP mode requested: 1 [ 5.331485] agpgart-articias 0000:00:00.0: AGP 1.0 bridge [ 5.337071] agpgart-articias 0000:00:00.0: putting AGP V2 device into 1x mode [ 5.344440] radeon 0000:01:00.0: putting AGP V2 device into 1x mode [ 5.350865] radeon 0000:01:00.0: GTT: 128M 0xC0000000 - 0xC7FFFFFF [ 5.357197] [drm] Generation 2 PCI interface, using max accessible memory [ 5.364111] radeon 0000:01:00.0: VRAM: 256M 0x0000000080000000 - 0x000000008FFFFFFF (256M used) [ 5.373060] [drm] Supports vblank timestamp caching Rev 1 (10.10.2010). [ 5.379815] [drm] Driver supports precise vblank timestamp query. [ 5.386068] [drm] radeon: irq initialized. [ 5.390264] [drm] Detected VRAM RAM=256M, BAR=128M [ 5.395177] [drm] RAM width 128bits DDR [ 5.399322] [TTM] Zone kernel: Available graphics memory: 380684 kiB. [ 5.406047] [TTM] Zone highmem: Available graphics memory: 773900 kiB. [ 5.412725] [TTM] Initializing pool allocator. [ 5.417395] [drm] radeon: 256M of VRAM memory ready [ 5.422442] [drm] radeon: 128M of GTT memory ready. [ 5.428527] agpgart-articias 0000:00:00.0: TLB flush! [ 5.433785] radeon 0000:01:00.0: WB disabled [ 5.438671] [drm] Loading R200 Microcode [ 5.444292] agpgart-articias 0000:00:00.0: TLB flush! [ 5.449629] [drm] radeon: ring at 0x00000000C0001000 [ 5.454761] [drm] ring test succeeded in 0 usecs [ 5.460620] agpgart-articias 0000:00:00.0: TLB flush! [ 5.465889] [drm] radeon: ib pool ready. [ 5.470212] [drm] ib test succeeded in 0 usecs [ 5.475939] agpgart-articias 0000:00:00.0: TLB flush! [ 5.490569] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326160 (GTT map 0xf1326000-0xf1426000) [ 5.503397] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf1326164 (GTT map 0xf1326000-0xf1426000) [ 5.516202] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326168 (GTT map 0xf1326000-0xf1426000) [ 5.528993] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf132616c (GTT map 0xf1326000-0xf1426000) [ 5.541777] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326170 (GTT map 0xf1326000-0xf1426000) [ 5.554535] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf1326174 (GTT map 0xf1326000-0xf1426000) [ 5.567303] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326178 (GTT map 0xf1326000-0xf1426000) [ 5.580049] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf132617c (GTT map 0xf1326000-0xf1426000) [ 5.592843] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326180 (GTT map 0xf1326000-0xf1426000) [ 5.605652] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf1326184 (GTT map 0xf1326000-0xf1426000) [ 5.618392] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326188 (GTT map 0xf1326000-0xf1426000) [ 5.631178] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf132618c (GTT map 0xf1326000-0xf1426000) [ 5.643970] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326190 (GTT map 0xf1326000-0xf1426000) [ 5.656769] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf1326194 (GTT map 0xf1326000-0xf1426000) [ 5.669494] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c0, expected 0xf1326198 (GTT map 0xf1326000-0xf1426000) [ 5.682293] [drm:radeon_test_moves] *ERROR* Incorrect GTT->VRAM copy 0: Got 0xf13268c4, expected 0xf132619c (GTT map 0xf1326000-0xf1426000) [ 5.878809] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ec0, expected 0xf1570ec0 (VRAM map 0xf1480000-0xf1580000) [ 5.891734] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ec4, expected 0xf1570ec4 (VRAM map 0xf1480000-0xf1580000) [ 5.904616] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ec8, expected 0xf1570ec8 (VRAM map 0xf1480000-0xf1580000) [ 5.917460] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ecc, expected 0xf1570ecc (VRAM map 0xf1480000-0xf1580000) [ 5.930286] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ed0, expected 0xf1570ed0 (VRAM map 0xf1480000-0xf1580000) [ 5.943164] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ed4, expected 0xf1570ed4 (VRAM map 0xf1480000-0xf1580000) [ 5.956052] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ed8, expected 0xf1570ed8 (VRAM map 0xf1480000-0xf1580000) [ 5.968898] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416edc, expected 0xf1570edc (VRAM map 0xf1480000-0xf1580000) [ 5.981758] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ee0, expected 0xf1570ee0 (VRAM map 0xf1480000-0xf1580000) [ 5.994593] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ee4, expected 0xf1570ee4 (VRAM map 0xf1480000-0xf1580000) [ 6.007455] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ee8, expected 0xf1570ee8 (VRAM map 0xf1480000-0xf1580000) [ 6.020309] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416eec, expected 0xf1570eec (VRAM map 0xf1480000-0xf1580000) [ 6.033208] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ef0, expected 0xf1570ef0 (VRAM map 0xf1480000-0xf1580000) [ 6.046077] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ef4, expected 0xf1570ef4 (VRAM map 0xf1480000-0xf1580000) [ 6.058964] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416ef8, expected 0xf1570ef8 (VRAM map 0xf1480000-0xf1580000) [ 6.071850] [drm:radeon_test_moves] *ERROR* Incorrect VRAM->GTT copy 0: Got 0xf1416efc, expected 0xf1570efc (VRAM map 0xf1480000-0xf1580000) For the GTT->VRAM copy it looks like the AGPGART driver at least gets the graphics aperture translation table right, as both the returned and expected values are within a page. But the page offset of the returned values (0x8c0, 0x8c4) makes me wonder whether I'm fooled by a hardware bug or a cache coherency problem. The VRAM->GTT copy totally puzzles me, as it returns a wrong page address, but the offset is fine!? br, Gerhard -- Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
