[PATCH 2/3] drm/i915/psr: Improve fast and IO wake lines calculation
kernel test robot
lkp at intel.com
Thu Feb 22 00:42:05 UTC 2024
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@intel.com/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@intel.com/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 at intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202402220859.K3oSmRCi-lkp@intel.com/
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
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