Hi Stanislav, Thank you for the patch! Yet something to improve: [auto build test ERROR on bb6d3fb354c5ee8d6bde2d576eb7220ea09862b9] url: https://github.com/0day-ci/linux/commits/Stanislav-Spassov/Improve-PCI-device-post-reset-readiness-polling/20200303-043307 base: bb6d3fb354c5ee8d6bde2d576eb7220ea09862b9 config: i386-randconfig-d001-20200302 (attached as .config) compiler: gcc-7 (Debian 7.5.0-5) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): ld: drivers/pci/pci-acpi.o: in function `pci_acpi_optimize_delay': >> drivers/pci/pci-acpi.c:1242: undefined reference to `__udivdi3' >> ld: drivers/pci/pci-acpi.c:1243: undefined reference to `__umoddi3' ld: drivers/pci/pci-acpi.c:1250: undefined reference to `__udivdi3' ld: drivers/pci/pci-acpi.c:1251: undefined reference to `__umoddi3' vim +1242 drivers/pci/pci-acpi.c 1178 1179 /** 1180 * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI 1181 * @pdev: the PCI device whose delay is to be updated 1182 * @handle: ACPI handle of this device 1183 * 1184 * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM 1185 * Function 9 of the device, and cache the parent host bridge's flag for 1186 * ignoring reset delay upon Sx Resume (the flag is originally set in 1187 * acpi_pci_add_bus through _DSM Function 8). 1188 * 1189 * Function 9, "Device Readiness Durations," applies only to the object 1190 * where it is located. It returns delay durations required after various 1191 * events if the device requires less time than the spec requires. 1192 * Values provided by this function can only be used to lower (reduce) the 1193 * latency required by specification or values discovered from device. 1194 * 1195 * This _DSM function is defined by the PCI Firmware Specification Rev 3.2 1196 * (January 26, 2015), after originally introduced by a draft ECN of 1197 * January 28, 2014, titled "ACPI additions for FW latency optimizations." 1198 * 1199 * XXX The PCI Firmware Specification contradicts itself by stating, in addition 1200 * to the above "can only be used to lower (reduce)", that also: 1201 * Values must be interpreted as overriding any Configuration Ready indicator 1202 * from hardware, whether increasing or decreasing required delays. This 1203 * includes ignoring FRS and DRS notifications where overridden by this 1204 * _DSM function, as well as ignoring values specified in the Readiness Time 1205 * Reporting Extended Capability, if present. 1206 * Meanwhile, the PCI Express Base Specification Revision 5.0 Version 1.0 1207 * (22 May 2019) states in section 7.9.17 Readiness Time Reporting Extended 1208 * Capability: 1209 * Software is permitted to issue requests upon the earliest of: 1210 * - Receiving a Readiness Notification messages 1211 * - Waiting the appropriate time as per relevant specifications 1212 * - Waiting the time indicated in the associated field of this capability 1213 * - Waiting the time defined by system software or firmware 1214 * The kernel does not yet support Readiness Notifications, and does not yet 1215 * use a Readiness Time Reporting capability if present, so we do not need to 1216 * worry about the prioritization for now. 1217 */ 1218 static void pci_acpi_optimize_delay(struct pci_dev *pdev, 1219 acpi_handle handle) 1220 { 1221 struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus); 1222 /* 1223 * _DSM 9 provides values in microseconds, but the kernel uses msleep() 1224 * when waiting, so the code below rounds up when setting value in ms 1225 */ 1226 u64 value_us; 1227 int value; 1228 union acpi_object *obj, *elements; 1229 1230 pdev->ignore_reset_delay_on_sx_resume = 1231 bridge->ignore_reset_delay_on_sx_resume; 1232 1233 obj = acpi_evaluate_dsm(handle, &pci_acpi_dsm_guid, 3, 1234 FUNCTION_DELAY_DSM, NULL); 1235 if (!obj) 1236 return; 1237 1238 if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) { 1239 elements = obj->package.elements; 1240 if (elements[0].type == ACPI_TYPE_INTEGER) { 1241 value_us = elements[0].integer.value; > 1242 value = (int)(value_us / 1000); > 1243 if (value_us % 1000 > 0) 1244 value++; 1245 if (value < PCI_PM_D3COLD_WAIT) 1246 pdev->d3cold_delay = value; 1247 } 1248 if (elements[3].type == ACPI_TYPE_INTEGER) { 1249 value_us = elements[3].integer.value; 1250 value = (int)(value_us / 1000); 1251 if (value_us % 1000 > 0) 1252 value++; 1253 if (value < PCI_PM_D3_WAIT) 1254 pdev->d3_delay = value; 1255 } 1256 } 1257 ACPI_FREE(obj); 1258 } 1259 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
Attachment:
.config.gz
Description: application/gzip
