diff options
author | Rebecca N. Palmer <rebecca_palmer@zoho.com> | 2015-05-16 18:52:59 +0100 |
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committer | Zhigang Gong <gongzg@freedesktop.org> | 2015-05-18 02:12:01 -0700 |
commit | 00f749ed9a5b7a900328041ccdcbb36bb83500d5 (patch) | |
tree | a009d166a308d045f25b935f106a19f9eabf68a7 /Software/Beignet.mdwn | |
parent | ef0794d3e5548b412ce22e44c6484c1272e516a0 (diff) |
Docs: update/clarify Haswell issues
Reflect recent beignet and Linux changes.
Diffstat (limited to 'Software/Beignet.mdwn')
-rw-r--r-- | Software/Beignet.mdwn | 40 |
1 files changed, 26 insertions, 14 deletions
diff --git a/Software/Beignet.mdwn b/Software/Beignet.mdwn index 8504c8f6..710fc982 100644 --- a/Software/Beignet.mdwn +++ b/Software/Beignet.mdwn @@ -140,7 +140,7 @@ Supported Targets * 3rd Generation Intel Core Processors * Intel “Bay Trail” platforms with Intel HD Graphics - * 4th Generation Intel Core Processors, need kernel patch currently, see the "Known Issues" section. + * 4th Generation Intel Core Processors "Haswell", need kernel patch currently, see the "Known Issues" section. * 5th Generation Intel Core Processors "Broadwell". Known Issues @@ -161,22 +161,34 @@ Known Issues But this command is a little bit dangerous, as if your kernel really hang, then the gpu will lock up forever until a reboot. -* Almost all unit tests fail. - There is a known issue in some versions of linux kernel which enable register whitelist feature - but miss some necessary registers which are required for beignet. For non-HSW platforms, the - problematic version are around 3.15 and 3.16 which have commit f0a346b... but haven't commit - c9224f... If it is the case, you can apply c9224f... manually and rebuild the kernel or just - disable the parse command by invoke the following command (use Ubuntu as an example): +* "Beignet: self-test failed" and almost all unit tests fail. + Linux 3.15 and 3.16 (commits [f0a346b](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f0a346bdafaf6fc4a51df9ddf1548fd888f860d8) + to [c9224fa](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=c9224faa59c3071ecfa2d4b24592f4eb61e57069)) + enable the register whitelist by default but miss some registers needed + for Beignet. + + This can be fixed by upgrading Linux, or by disabling the whitelist: `# echo 0 > /sys/module/i915/parameters/enable_cmd_parser` - For HSW platforms, this issue exists in all linux kernel version after 3.15. We always need - to execute the above command. - -* Some unit test cases, maybe 20 to 30, fail on 4th Generation (HSW) platform. - _The 4th Generation Intel Core Processors's support requires some Linux kernel - modification_. You need to apply the patch at: - [https://01.org/zh/beignet/downloads/linux-kernel-patch-hsw-support](https://01.org/zh/beignet/downloads/linux-kernel-patch-hsw-support) + On Haswell hardware, Beignet 1.0.1 to 1.0.3 also required the + above workaround on later Linux versions, but this _should not_ be + required in current (after [83f8739](http://cgit.freedesktop.org/beignet/commit/?id=83f8739b6fc4893fac60145326052ccb5cf653dc)) + git master. + +* "Beignet: self-test failed" and 15-30 unit tests fail on 4th Generation (Haswell) hardware. + On Haswell, shared local memory (\_\_local) does not work at all on + Linux <= 4.0, and requires the i915.enable_ppgtt=2 [boot parameter](https://wiki.ubuntu.com/Kernel/KernelBootParameters) + on Linux 4.1. + + This will be fixed in Linux 4.2; older versions can be fixed with + [this patch](https://01.org/zh/beignet/downloads/linux-kernel-patch-hsw-support). + + If you do not need \_\_local, you can override the self-test with + + `export OCL_IGNORE_SELF_TEST=1` + + but using \_\_local after this may silently give wrong results. * Precision issue. Currently Gen does not provide native support of high precision math functions |