Hi Jouni, kernel test robot noticed the following build warnings: [auto build test WARNING on drm-intel/for-linux-next] [also build test WARNING on drm-tip/drm-tip next-20240221] [cannot apply to drm-intel/for-linux-next-fixes linus/master v6.8-rc5] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Jouni-H-gander/drm-i915-display-Add-aux-function-pointer-for-fast-wake-sync-pulse-count/20240221-160220 base: git://anongit.freedesktop.org/drm-intel for-linux-next patch link: https://lore.kernel.org/r/20240221075322.2764209-3-jouni.hogander%40intel.com patch subject: [PATCH 2/3] drm/i915/psr: Improve fast and IO wake lines calculation config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20240222/202402220859.K3oSmRCi-lkp@xxxxxxxxx/config) compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 36adfec155de366d722f2bac8ff9162289dcf06c) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240222/202402220859.K3oSmRCi-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202402220859.K3oSmRCi-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/gpu/drm/i915/display/intel_psr.c:28: In file included from drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h:15: In file included from drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h:11: In file included from drivers/gpu/drm/xe/xe_bo.h:11: In file included from drivers/gpu/drm/xe/xe_bo_types.h:9: In file included from include/linux/iosys-map.h:10: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:78: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 547 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) | ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' 102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) | ^ In file included from drivers/gpu/drm/i915/display/intel_psr.c:28: In file included from drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h:15: In file included from drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h:11: In file included from drivers/gpu/drm/xe/xe_bo.h:11: In file included from drivers/gpu/drm/xe/xe_bo_types.h:9: In file included from include/linux/iosys-map.h:10: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:78: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) | ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' 115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) | ^ In file included from drivers/gpu/drm/i915/display/intel_psr.c:28: In file included from drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h:15: In file included from drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h:11: In file included from drivers/gpu/drm/xe/xe_bo.h:11: In file included from drivers/gpu/drm/xe/xe_bo_types.h:9: In file included from include/linux/iosys-map.h:10: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:78: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 584 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 692 | readsb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 700 | readsw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 708 | readsl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 717 | writesb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 726 | writesw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 735 | writesl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ >> drivers/gpu/drm/i915/display/intel_psr.c:1182:6: warning: variable 'io_wake_time' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] 1182 | if (intel_dp->get_aux_fw_sync_len) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/i915/display/intel_psr.c:1203:34: note: uninitialized use occurs here 1203 | &crtc_state->hw.adjusted_mode, io_wake_time); | ^~~~~~~~~~~~ drivers/gpu/drm/i915/display/intel_psr.c:1182:2: note: remove the 'if' if its condition is always false 1182 | if (intel_dp->get_aux_fw_sync_len) { | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1183 | int io_wake_time = get_io_wake_time(intel_dp, crtc_state); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1184 | int tfw_exit_latency = 20; /* eDP spec */ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1185 | int phy_wake = 4; /* eDP spec */ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1186 | int preamble = 8; /* eDP spec */ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1187 | int precharge = intel_dp->get_aux_fw_sync_len() - preamble; | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1188 | 1189 | io_wake_time = max(precharge, io_wake_time) + preamble + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1190 | phy_wake + tfw_exit_latency; | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1191 | fast_wake_time = precharge + preamble + phy_wake + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1192 | tfw_exit_latency; | ~~~~~~~~~~~~~~~~~ 1193 | 1194 | /* TODO: Check how we can use ALPM_CTL fast wake extended field */ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1195 | max_wake_lines = 12; | ~~~~~~~~~~~~~~~~~~~~ 1196 | } else { | ~~~~~~ drivers/gpu/drm/i915/display/intel_psr.c:1179:33: note: initialize the variable 'io_wake_time' to silence this warning 1179 | int io_wake_lines, io_wake_time, fast_wake_lines, fast_wake_time; | ^ | = 0 13 warnings generated. vim +1182 drivers/gpu/drm/i915/display/intel_psr.c 1174 1175 static bool _compute_alpm_params(struct intel_dp *intel_dp, 1176 struct intel_crtc_state *crtc_state) 1177 { 1178 struct drm_i915_private *i915 = dp_to_i915(intel_dp); 1179 int io_wake_lines, io_wake_time, fast_wake_lines, fast_wake_time; 1180 u8 max_wake_lines; 1181 > 1182 if (intel_dp->get_aux_fw_sync_len) { 1183 int io_wake_time = get_io_wake_time(intel_dp, crtc_state); 1184 int tfw_exit_latency = 20; /* eDP spec */ 1185 int phy_wake = 4; /* eDP spec */ 1186 int preamble = 8; /* eDP spec */ 1187 int precharge = intel_dp->get_aux_fw_sync_len() - preamble; 1188 1189 io_wake_time = max(precharge, io_wake_time) + preamble + 1190 phy_wake + tfw_exit_latency; 1191 fast_wake_time = precharge + preamble + phy_wake + 1192 tfw_exit_latency; 1193 1194 /* TODO: Check how we can use ALPM_CTL fast wake extended field */ 1195 max_wake_lines = 12; 1196 } else { 1197 io_wake_time = 50; 1198 fast_wake_time = 32; 1199 max_wake_lines = 8; 1200 } 1201 1202 io_wake_lines = intel_usecs_to_scanlines( 1203 &crtc_state->hw.adjusted_mode, io_wake_time); 1204 fast_wake_lines = intel_usecs_to_scanlines( 1205 &crtc_state->hw.adjusted_mode, fast_wake_time); 1206 1207 if (io_wake_lines > max_wake_lines || 1208 fast_wake_lines > max_wake_lines) 1209 return false; 1210 1211 if (!_lnl_compute_alpm_params(intel_dp, crtc_state)) 1212 return false; 1213 1214 if (i915->display.params.psr_safest_params) 1215 io_wake_lines = fast_wake_lines = max_wake_lines; 1216 1217 /* According to Bspec lower limit should be set as 7 lines. */ 1218 intel_dp->psr.alpm_parameters.io_wake_lines = max(io_wake_lines, 7); 1219 intel_dp->psr.alpm_parameters.fast_wake_lines = max(fast_wake_lines, 7); 1220 1221 return true; 1222 } 1223 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
