tree: https://github.com/intel/linux-intel-lts.git 5.4/yocto head: 8bbfe55bfdb2905c35914605bc1b4a4404d86649 commit: 2521b097a48688b899e3db9cb855aa1ec59b02e8 [8/24] drm/i915/gvt: Rebase IDV 2.1 direct display to 5.4.x. config: x86_64-randconfig-a014-20200916 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9e3842d60351f986d77dfe0a94f76e4fd895f188) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git checkout 2521b097a48688b899e3db9cb855aa1ec59b02e8 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): skl_wm_method1(const struct drm_i915_private *dev_priv, u32 pixel_rate, ^ drivers/gpu/drm/i915/intel_pm.c:4522:1: note: declare 'static' if the function is not intended to be used outside of this translation unit uint_fixed_16_16_t ^ static skl_wm_method2(u32 pixel_rate, u32 pipe_htotal, u32 latency, ^ drivers/gpu/drm/i915/intel_pm.c:4541:1: note: declare 'static' if the function is not intended to be used outside of this translation unit uint_fixed_16_16_t ^ static intel_get_linetime_us(const struct intel_crtc_state *crtc_state) ^ drivers/gpu/drm/i915/intel_pm.c:4558:1: note: declare 'static' if the function is not intended to be used outside of this translation unit uint_fixed_16_16_t ^ static void skl_compute_transition_wm(const struct intel_crtc_state *crtc_state, ^ drivers/gpu/drm/i915/intel_pm.c:4886:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void skl_compute_transition_wm(const struct intel_crtc_state *crtc_state, ^ static 4 errors generated. # https://github.com/intel/linux-intel-lts/commit/2521b097a48688b899e3db9cb... git remote add intel-linux-intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-linux-intel-lts 5.4/yocto git checkout 2521b097a48688b899e3db9cb855aa1ec59b02e8 vim +/skl_wm_method1 +4523 drivers/gpu/drm/i915/intel_pm.c b9cec07585cf1f5 Damien Lespiau 2014-11-04 4515 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4516 /* 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4517 * The max latency should be 257 (max the punit can code is 255 and we add 2us ac484963f979b6a Ville Syrjälä 2016-01-20 4518 * for the read latency) and cpp should always be <= 8, so that 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4519 * should allow pixel_rate up to ~2 GHz which seems sufficient since max 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4520 * 2xcdclk is 1350 MHz and the pixel rate should never exceed that. 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4521 */ 2521b097a48688b Colin Xu 2020-04-14 4522 uint_fixed_16_16_t 5ce9a6497914b21 Jani Nikula 2019-01-18 @4523 skl_wm_method1(const struct drm_i915_private *dev_priv, u32 pixel_rate, 5ce9a6497914b21 Jani Nikula 2019-01-18 4524 u8 cpp, u32 latency, u32 dbuf_block_size) 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4525 { 5ce9a6497914b21 Jani Nikula 2019-01-18 4526 u32 wm_intermediate_val; b95320bdf2d8910 Mahesh Kumar 2016-12-01 4527 uint_fixed_16_16_t ret; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4528 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4529 if (latency == 0) b95320bdf2d8910 Mahesh Kumar 2016-12-01 4530 return FP_16_16_MAX; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4531 b95320bdf2d8910 Mahesh Kumar 2016-12-01 4532 wm_intermediate_val = latency * pixel_rate * cpp; df8ee19087d24ca Mahesh Kumar 2018-01-30 4533 ret = div_fixed16(wm_intermediate_val, 1000 * dbuf_block_size); 6c64dd378aca528 Paulo Zanoni 2017-08-11 4534 6c64dd378aca528 Paulo Zanoni 2017-08-11 4535 if (INTEL_GEN(dev_priv) >= 10) 6c64dd378aca528 Paulo Zanoni 2017-08-11 4536 ret = add_fixed16_u32(ret, 1); 6c64dd378aca528 Paulo Zanoni 2017-08-11 4537 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4538 return ret; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4539 } 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4540 2521b097a48688b Colin Xu 2020-04-14 4541 uint_fixed_16_16_t 5ce9a6497914b21 Jani Nikula 2019-01-18 @4542 skl_wm_method2(u32 pixel_rate, u32 pipe_htotal, u32 latency, b95320bdf2d8910 Mahesh Kumar 2016-12-01 4543 uint_fixed_16_16_t plane_blocks_per_line) 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4544 { 5ce9a6497914b21 Jani Nikula 2019-01-18 4545 u32 wm_intermediate_val; b95320bdf2d8910 Mahesh Kumar 2016-12-01 4546 uint_fixed_16_16_t ret; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4547 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4548 if (latency == 0) b95320bdf2d8910 Mahesh Kumar 2016-12-01 4549 return FP_16_16_MAX; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4550 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4551 wm_intermediate_val = latency * pixel_rate; b95320bdf2d8910 Mahesh Kumar 2016-12-01 4552 wm_intermediate_val = DIV_ROUND_UP(wm_intermediate_val, b95320bdf2d8910 Mahesh Kumar 2016-12-01 4553 pipe_htotal * 1000); eac2cb81fb87223 Kumar, Mahesh 2017-07-05 4554 ret = mul_u32_fixed16(wm_intermediate_val, plane_blocks_per_line); 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4555 return ret; 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4556 } 2d41c0b59afcdd8 Pradeep Bhat 2014-11-04 4557 2521b097a48688b Colin Xu 2020-04-14 4558 uint_fixed_16_16_t ec193640819e014 Maarten Lankhorst 2019-06-28 @4559 intel_get_linetime_us(const struct intel_crtc_state *crtc_state) d555cb5827d6032 Kumar, Mahesh 2017-05-17 4560 { 5ce9a6497914b21 Jani Nikula 2019-01-18 4561 u32 pixel_rate; 5ce9a6497914b21 Jani Nikula 2019-01-18 4562 u32 crtc_htotal; d555cb5827d6032 Kumar, Mahesh 2017-05-17 4563 uint_fixed_16_16_t linetime_us; d555cb5827d6032 Kumar, Mahesh 2017-05-17 4564 3dd5d78f700217d Maarten Lankhorst 2019-10-31 4565 if (!crtc_state->hw.active) eac2cb81fb87223 Kumar, Mahesh 2017-07-05 4566 return u32_to_fixed16(0); d555cb5827d6032 Kumar, Mahesh 2017-05-17 4567 ec193640819e014 Maarten Lankhorst 2019-06-28 4568 pixel_rate = crtc_state->pixel_rate; d555cb5827d6032 Kumar, Mahesh 2017-05-17 4569 d555cb5827d6032 Kumar, Mahesh 2017-05-17 4570 if (WARN_ON(pixel_rate == 0)) eac2cb81fb87223 Kumar, Mahesh 2017-07-05 4571 return u32_to_fixed16(0); d555cb5827d6032 Kumar, Mahesh 2017-05-17 4572 3dd5d78f700217d Maarten Lankhorst 2019-10-31 4573 crtc_htotal = crtc_state->hw.adjusted_mode.crtc_htotal; eac2cb81fb87223 Kumar, Mahesh 2017-07-05 4574 linetime_us = div_fixed16(crtc_htotal * 1000, pixel_rate); d555cb5827d6032 Kumar, Mahesh 2017-05-17 4575 d555cb5827d6032 Kumar, Mahesh 2017-05-17 4576 return linetime_us; d555cb5827d6032 Kumar, Mahesh 2017-05-17 4577 } d555cb5827d6032 Kumar, Mahesh 2017-05-17 4578 :::::: The code at line 4523 was first introduced by commit :::::: 5ce9a6497914b21ca995ebbc0322b287b28176e8 drm/i915/pm: switch to kernel types :::::: TO: Jani Nikula <jani.nikula(a)intel.com&gt; :::::: CC: Jani Nikula <jani.nikula(a)intel.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org