/* Copyright 2013-2016 IBM Corp. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or * implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * Handle ChipTOD chip & configure core timebases */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX_RESET_PATCH_SIZE 64 static uint32_t slw_saved_reset[MAX_RESET_PATCH_SIZE]; static bool slw_current_le = false; /* SLW timer related stuff */ static bool slw_has_timer; static uint64_t slw_timer_inc; static uint64_t slw_timer_target; static uint32_t slw_timer_chip; static uint64_t slw_last_gen; static uint64_t slw_last_gen_stamp; DEFINE_LOG_ENTRY(OPAL_RC_SLW_INIT, OPAL_PLATFORM_ERR_EVT, OPAL_SLW, OPAL_PLATFORM_FIRMWARE, OPAL_PREDICTIVE_ERR_GENERAL, OPAL_NA); DEFINE_LOG_ENTRY(OPAL_RC_SLW_SET, OPAL_PLATFORM_ERR_EVT, OPAL_SLW, OPAL_PLATFORM_FIRMWARE, OPAL_INFO, OPAL_NA); DEFINE_LOG_ENTRY(OPAL_RC_SLW_GET, OPAL_PLATFORM_ERR_EVT, OPAL_SLW, OPAL_PLATFORM_FIRMWARE, OPAL_INFO, OPAL_NA); DEFINE_LOG_ENTRY(OPAL_RC_SLW_REG, OPAL_PLATFORM_ERR_EVT, OPAL_SLW, OPAL_PLATFORM_FIRMWARE, OPAL_INFO, OPAL_NA); static void slw_do_rvwinkle(void *data) { struct cpu_thread *cpu = this_cpu(); struct cpu_thread *master = data; uint64_t lpcr = mfspr(SPR_LPCR); struct proc_chip *chip; /* Setup our ICP to receive IPIs */ icp_prep_for_pm(); /* Setup LPCR to wakeup on external interrupts only */ mtspr(SPR_LPCR, ((lpcr & ~SPR_LPCR_P8_PECE) | SPR_LPCR_P8_PECE2)); prlog(PR_DEBUG, "SLW: CPU PIR 0x%04x goint to rvwinkle...\n", cpu->pir); /* Tell that we got it */ cpu->state = cpu_state_rvwinkle; enter_pm_state(1); /* Restore SPRs */ init_shared_sprs(); init_replicated_sprs(); /* Ok, it's ours again */ cpu->state = cpu_state_active; prlog(PR_DEBUG, "SLW: CPU PIR 0x%04x woken up !\n", cpu->pir); /* Cleanup our ICP */ reset_cpu_icp(); /* Resync timebase */ chiptod_wakeup_resync(); /* Restore LPCR */ mtspr(SPR_LPCR, lpcr); /* If we are passed a master pointer we are the designated * waker, let's proceed. If not, return, we are finished. */ if (!master) return; prlog(PR_DEBUG, "SLW: CPU PIR 0x%04x waiting for master...\n", cpu->pir); /* Allriiiight... now wait for master to go down */ while(master->state != cpu_state_rvwinkle) sync(); /* XXX Wait one second ! (should check xscom state ? ) */ time_wait_ms(1000); for_each_chip(chip) { struct cpu_thread *c; uint64_t tmp; for_each_available_core_in_chip(c, chip->id) { xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(pir_to_core_id(c->pir), EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); prlog(PR_TRACE, "SLW: core %x:%x" " history: 0x%016llx (mid2)\n", chip->id, pir_to_core_id(c->pir), tmp); } } prlog(PR_DEBUG, "SLW: Waking master (PIR 0x%04x)...\n", master->pir); /* Now poke all the secondary threads on the master's core */ for_each_cpu(cpu) { if (!cpu_is_sibling(cpu, master) || (cpu == master)) continue; icp_kick_cpu(cpu); /* Wait for it to claim to be back (XXX ADD TIMEOUT) */ while(cpu->state != cpu_state_active) sync(); } /* Now poke the master and be gone */ icp_kick_cpu(master); } static void slw_patch_reset(void) { uint32_t *src, *dst, *sav; BUILD_ASSERT((&reset_patch_end - &reset_patch_start) <= MAX_RESET_PATCH_SIZE); src = &reset_patch_start; dst = (uint32_t *)0x100; sav = slw_saved_reset; while(src < &reset_patch_end) { *(sav++) = *(dst); *(dst++) = *(src++); } sync_icache(); } static void slw_unpatch_reset(void) { extern uint32_t reset_patch_start; extern uint32_t reset_patch_end; uint32_t *src, *dst, *sav; src = &reset_patch_start; dst = (uint32_t *)0x100; sav = slw_saved_reset; while(src < &reset_patch_end) { *(dst++) = *(sav++); src++; } sync_icache(); } static bool slw_general_init(struct proc_chip *chip, struct cpu_thread *c) { uint32_t core = pir_to_core_id(c->pir); uint64_t tmp; int rc; /* PowerManagement GP0 clear PM_DISABLE */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_GP0), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Failed to read PM_GP0\n"); return false; } tmp = tmp & ~0x8000000000000000ULL; rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_GP0), tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Failed to write PM_GP0\n"); return false; } prlog(PR_TRACE, "SLW: PMGP0 set to 0x%016llx\n", tmp); /* Read back for debug */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_GP0), &tmp); if (rc) log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Failed to re-read PM_GP0. Continuing...\n"); prlog(PR_TRACE, "SLW: PMGP0 read 0x%016llx\n", tmp); return true; } static bool slw_set_overrides(struct proc_chip *chip, struct cpu_thread *c) { uint32_t core = pir_to_core_id(c->pir); uint64_t tmp; int rc; /* * Set ENABLE_IGNORE_RECOV_ERRORS in OHA_MODE_REG * * XXX FIXME: This should be only done for "forced" winkle such as * when doing repairs or LE transition, and we should restore the * original value when done */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX(core, PM_OHA_MODE_REG), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to read PM_OHA_MODE_REG\n"); return false; } tmp = tmp | 0x8000000000000000ULL; rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX(core, PM_OHA_MODE_REG), tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_OHA_MODE_REG\n"); return false; } prlog(PR_TRACE, "SLW: PM_OHA_MODE_REG set to 0x%016llx\n", tmp); /* Read back for debug */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX(core, PM_OHA_MODE_REG),&tmp); prlog(PR_TRACE, "SLW: PM_OHA_MODE_REG read 0x%016llx\n", tmp); /* * Clear special wakeup bits that could hold power mgt * * XXX FIXME: See above */ rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_SPECIAL_WAKEUP_FSP), 0); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_SPECIAL_WAKEUP_FSP\n"); return false; } rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_SPECIAL_WAKEUP_OCC), 0); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_SPECIAL_WAKEUP_OCC\n"); return false; } rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_SPECIAL_WAKEUP_PHYP), 0); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_SPECIAL_WAKEUP_PHYP\n"); return false; } return true; } static bool slw_set_overrides_p9(struct proc_chip *chip, struct cpu_thread *c) { uint64_t tmp; int rc; uint32_t core = pir_to_core_id(c->pir); /* MAMBO does not require this init */ if (proc_chip_quirks & QUIRK_MAMBO_CALLOUTS) { return true; } /* Clear special wakeup bits that could hold power mgt */ rc = xscom_write(chip->id, XSCOM_ADDR_P9_EC_SLAVE(core, EC_PPM_SPECIAL_WKUP_HYP), 0); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write EC_PPM_SPECIAL_WKUP_HYP\n"); return false; } /* Read back for debug */ rc = xscom_read(chip->id, XSCOM_ADDR_P9_EC_SLAVE(core, EC_PPM_SPECIAL_WKUP_HYP), &tmp); prlog(PR_NOTICE, "SLW: EC_PPM_SPECIAL_WKUP_HYP read 0x%016llx\n", tmp); rc = xscom_read(chip->id, XSCOM_ADDR_P9_EC_SLAVE(core, EC_PPM_SPECIAL_WKUP_OTR), &tmp); if (tmp) prlog(PR_WARNING, "SLW: EC_PPM_SPECIAL_WKUP_OTR read 0x%016llx\n", tmp); return true; } static bool slw_unset_overrides(struct proc_chip *chip, struct cpu_thread *c) { uint32_t core = pir_to_core_id(c->pir); /* XXX FIXME: Save and restore the overrides */ prlog(PR_DEBUG, "SLW: slw_unset_overrides %x:%x\n", chip->id, core); return true; } static bool slw_set_idle_mode(struct proc_chip *chip, struct cpu_thread *c) { uint32_t core = pir_to_core_id(c->pir); uint64_t tmp; int rc; /* * PM GP1 allows fast/deep mode to be selected independently for sleep * and winkle. Init PM GP1 so that sleep happens in fast mode and * winkle happens in deep mode. * Make use of the OR XSCOM for this since the OCC might be manipulating * the PM_GP1 register as well. Before doing this ensure that the bits * managing idle states are cleared so as to override any bits set at * init time. */ tmp = ~EX_PM_GP1_SLEEP_WINKLE_MASK; rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_CLEAR_GP1), tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_GP1\n"); return false; } rc = xscom_write(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_SET_GP1), EX_PM_SETUP_GP1_FAST_SLEEP_DEEP_WINKLE); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_SET), "SLW: Failed to write PM_GP1\n"); return false; } /* Read back for debug */ xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_GP1), &tmp); prlog(PR_TRACE, "SLW: PMGP1 read 0x%016llx\n", tmp); return true; } static bool slw_get_idle_state_history(struct proc_chip *chip, struct cpu_thread *c) { uint32_t core = pir_to_core_id(c->pir); uint64_t tmp; int rc; /* Cleanup history */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_GET), "SLW: Failed to read PM_IDLE_STATE_HISTORY\n"); return false; } prlog(PR_TRACE, "SLW: core %x:%x history: 0x%016llx (old1)\n", chip->id, core, tmp); rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(core, EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_GET), "SLW: Failed to read PM_IDLE_STATE_HISTORY\n"); return false; } prlog(PR_TRACE, "SLW: core %x:%x history: 0x%016llx (old2)\n", chip->id, core, tmp); return true; } static bool idle_prepare_core(struct proc_chip *chip, struct cpu_thread *c) { prlog(PR_TRACE, "FASTSLEEP: Prepare core %x:%x\n", chip->id, pir_to_core_id(c->pir)); if(!slw_general_init(chip, c)) return false; if(!slw_set_overrides(chip, c)) return false; if(!slw_set_idle_mode(chip, c)) return false; if(!slw_get_idle_state_history(chip, c)) return false; return true; } /* Define device-tree fields */ #define MAX_NAME_LEN 16 struct cpu_idle_states { char name[MAX_NAME_LEN]; u32 latency_ns; u32 residency_ns; /* * Register value/mask used to select different idle states. * PMICR in POWER8 and PSSCR in POWER9 */ u64 pm_ctrl_reg_val; u64 pm_ctrl_reg_mask; u32 flags; }; static struct cpu_idle_states power7_cpu_idle_states[] = { { /* nap */ .name = "nap", .latency_ns = 4000, .residency_ns = 100000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_NAP_ENABLED \ | 0*OPAL_PM_SLEEP_ENABLED \ | 0*OPAL_PM_WINKLE_ENABLED \ | 0*OPAL_USE_PMICR, .pm_ctrl_reg_val = 0, .pm_ctrl_reg_mask = 0 }, }; static struct cpu_idle_states power8_cpu_idle_states[] = { { /* nap */ .name = "nap", .latency_ns = 4000, .residency_ns = 100000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_NAP_ENABLED \ | 0*OPAL_USE_PMICR, .pm_ctrl_reg_val = 0, .pm_ctrl_reg_mask = 0 }, { /* fast sleep (with workaround) */ .name = "fastsleep_", .latency_ns = 40000, .residency_ns = 300000000, .flags = 1*OPAL_PM_DEC_STOP \ | 1*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_SLEEP_ENABLED_ER1 \ | 0*OPAL_USE_PMICR, /* Not enabled until deep states are available */ .pm_ctrl_reg_val = OPAL_PM_FASTSLEEP_PMICR, .pm_ctrl_reg_mask = OPAL_PM_SLEEP_PMICR_MASK }, { /* Winkle */ .name = "winkle", .latency_ns = 10000000, .residency_ns = 1000000000, /* Educated guess (not measured). * Winkle is not currently used by * linux cpuidle subsystem so we * don't have real world user. * However, this should be roughly * accurate for when linux does * use it. */ .flags = 1*OPAL_PM_DEC_STOP \ | 1*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 1*OPAL_PM_LOSE_HYP_CONTEXT \ | 1*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_WINKLE_ENABLED \ | 0*OPAL_USE_PMICR, /* Currently choosing deep vs fast via EX_PM_GP1 reg */ .pm_ctrl_reg_val = 0, .pm_ctrl_reg_mask = 0 }, }; /* * cpu_idle_states for key idle states of POWER9 that we want to * exploit. * Note latency_ns and residency_ns are estimated values for now. */ static struct cpu_idle_states power9_cpu_idle_states[] = { { .name = "stop0_lite", /* Enter stop0 with no state loss */ .latency_ns = 200, .residency_ns = 2000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 0*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(0) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3), .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop0", .latency_ns = 300, .residency_ns = 3000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 0*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(0) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop1_lite", /* Enter stop1 with no state loss */ .latency_ns = 4900, .residency_ns = 49000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(1) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3), .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop1", .latency_ns = 5000, .residency_ns = 50000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(1) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop2_lite", /* Enter stop2 with no state loss */ .latency_ns = 9900, .residency_ns = 99000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(2) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3), .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop2", .latency_ns = 10000, .residency_ns = 100000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(2) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop4", .latency_ns = 100000, .residency_ns = 1000000, .flags = 1*OPAL_PM_DEC_STOP \ | 1*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 1*OPAL_PM_LOSE_HYP_CONTEXT \ | 1*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_DEEP, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(4) \ | OPAL_PM_PSSCR_MTL(7) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop8", .latency_ns = 2000000, .residency_ns = 20000000, .flags = 1*OPAL_PM_DEC_STOP \ | 1*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 1*OPAL_PM_LOSE_HYP_CONTEXT \ | 1*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_DEEP, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(8) \ | OPAL_PM_PSSCR_MTL(11) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop11", .latency_ns = 10000000, .residency_ns = 100000000, .flags = 1*OPAL_PM_DEC_STOP \ | 1*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 1*OPAL_PM_LOSE_HYP_CONTEXT \ | 1*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_DEEP, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(11) \ | OPAL_PM_PSSCR_MTL(11) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, }; /* Idle states supported for P9 DD1 */ static struct cpu_idle_states power9_dd1_cpu_idle_states[] = { { .name = "stop0_lite", .latency_ns = 200, .residency_ns = 2000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 0*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(0) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3), .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop1_lite", .latency_ns = 4900, .residency_ns = 49000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(1) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3), .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK }, { .name = "stop1", .latency_ns = 2050000, .residency_ns = 50000, .flags = 0*OPAL_PM_DEC_STOP \ | 0*OPAL_PM_TIMEBASE_STOP \ | 1*OPAL_PM_LOSE_USER_CONTEXT \ | 0*OPAL_PM_LOSE_HYP_CONTEXT \ | 0*OPAL_PM_LOSE_FULL_CONTEXT \ | 1*OPAL_PM_STOP_INST_FAST, .pm_ctrl_reg_val = OPAL_PM_PSSCR_RL(1) \ | OPAL_PM_PSSCR_MTL(3) \ | OPAL_PM_PSSCR_TR(3) \ | OPAL_PM_PSSCR_ESL \ | OPAL_PM_PSSCR_EC, .pm_ctrl_reg_mask = OPAL_PM_PSSCR_MASK } }; /* Add device tree properties to describe idle states */ void add_cpu_idle_state_properties(void) { struct dt_node *power_mgt; struct cpu_idle_states *states; struct proc_chip *chip; int nr_states; bool can_sleep = true; bool has_slw = true; bool has_stop_inst = false; u8 i; u64 *pm_ctrl_reg_val_buf; u64 *pm_ctrl_reg_mask_buf; u32 supported_states_mask; u32 stop_levels; /* Variables to track buffer length */ u8 name_buf_len; u8 num_supported_idle_states; /* Buffers to hold idle state properties */ char *name_buf, *alloced_name_buf; u32 *latency_ns_buf; u32 *residency_ns_buf; u32 *flags_buf; prlog(PR_DEBUG, "CPU idle state device tree init\n"); /* Create /ibm,opal/power-mgt if it doesn't exist already */ power_mgt = dt_new_check(opal_node, "power-mgt"); if (!power_mgt) { /** * @fwts-label CreateDTPowerMgtNodeFail * @fwts-advice OPAL failed to add the power-mgt device tree * node. This could mean that firmware ran out of memory, * or there's a bug somewhere. */ prlog(PR_ERR, "creating dt node /ibm,opal/power-mgt failed\n"); return; } /* * Chose the right state table for the chip * * XXX We use the first chip version, we should probably look * for the smaller of all chips instead.. */ chip = next_chip(NULL); assert(chip); if (chip->type == PROC_CHIP_P9_NIMBUS || chip->type == PROC_CHIP_P9_CUMULUS) { if (chip->ec_level == 0x10) { states = power9_dd1_cpu_idle_states; nr_states = ARRAY_SIZE(power9_dd1_cpu_idle_states); } else { states = power9_cpu_idle_states; nr_states = ARRAY_SIZE(power9_cpu_idle_states); } has_stop_inst = true; stop_levels = dt_prop_get_u32_def(power_mgt, "ibm,enabled-stop-levels", 0); if (!stop_levels) prerror("SLW: No stop levels available. Power saving is disabled!\n"); } else if (chip->type == PROC_CHIP_P8_MURANO || chip->type == PROC_CHIP_P8_VENICE || chip->type == PROC_CHIP_P8_NAPLES) { const struct dt_property *p; p = dt_find_property(dt_root, "ibm,enabled-idle-states"); if (p) prlog(PR_NOTICE, "SLW: HB-provided idle states property found\n"); states = power8_cpu_idle_states; nr_states = ARRAY_SIZE(power8_cpu_idle_states); /* Check if hostboot say we can sleep */ if (!p || !dt_prop_find_string(p, "fast-sleep")) { prlog(PR_WARNING, "SLW: Sleep not enabled by HB" " on this platform\n"); can_sleep = false; } /* Clip to NAP only on Murano and Venice DD1.x */ if ((chip->type == PROC_CHIP_P8_MURANO || chip->type == PROC_CHIP_P8_VENICE) && chip->ec_level < 0x20) { prlog(PR_NOTICE, "SLW: Sleep not enabled on P8 DD1.x\n"); can_sleep = false; } } else { states = power7_cpu_idle_states; nr_states = ARRAY_SIZE(power7_cpu_idle_states); } /* Enable deep idle states only if slw image is intact */ has_slw = (chip->slw_base && chip->slw_bar_size && chip->slw_image_size); /* * Currently we can't append strings and cells to dt properties. * So create buffers to which you can append values, then create * dt properties with this buffer content. */ /* Allocate memory to idle state property buffers. */ alloced_name_buf= malloc(nr_states * sizeof(char) * MAX_NAME_LEN); name_buf = alloced_name_buf; latency_ns_buf = malloc(nr_states * sizeof(u32)); residency_ns_buf= malloc(nr_states * sizeof(u32)); flags_buf = malloc(nr_states * sizeof(u32)); pm_ctrl_reg_val_buf = malloc(nr_states * sizeof(u64)); pm_ctrl_reg_mask_buf = malloc(nr_states * sizeof(u64)); name_buf_len = 0; num_supported_idle_states = 0; /* * Create a mask with the flags of all supported idle states * set. Use this to only add supported idle states to the * device-tree */ if (has_stop_inst) { /* Power 9 / POWER ISA 3.0 */ supported_states_mask = OPAL_PM_STOP_INST_FAST; if (has_slw) supported_states_mask |= OPAL_PM_STOP_INST_DEEP; } else { /* Power 7 and Power 8 */ supported_states_mask = OPAL_PM_NAP_ENABLED; if (can_sleep) supported_states_mask |= OPAL_PM_SLEEP_ENABLED | OPAL_PM_SLEEP_ENABLED_ER1; if (has_slw) supported_states_mask |= OPAL_PM_WINKLE_ENABLED; } for (i = 0; i < nr_states; i++) { /* For each state, check if it is one of the supported states. */ if (!(states[i].flags & supported_states_mask)) continue; /* We can only use the stop levels that HB has made available */ if (has_stop_inst) { u32 level = 31 - (states[i].pm_ctrl_reg_val & OPAL_PM_PSSCR_RL_MASK); if (!(stop_levels & (1ul << level))) continue; } prlog(PR_NOTICE, "SLW: Enabling: %s\n", states[i].name); /* * If a state is supported add each of its property * to its corresponding property buffer. */ strncpy(name_buf, states[i].name, MAX_NAME_LEN); name_buf = name_buf + strlen(states[i].name) + 1; *latency_ns_buf = cpu_to_fdt32(states[i].latency_ns); latency_ns_buf++; *residency_ns_buf = cpu_to_fdt32(states[i].residency_ns); residency_ns_buf++; *flags_buf = cpu_to_fdt32(states[i].flags); flags_buf++; *pm_ctrl_reg_val_buf = cpu_to_fdt64(states[i].pm_ctrl_reg_val); pm_ctrl_reg_val_buf++; *pm_ctrl_reg_mask_buf = cpu_to_fdt64(states[i].pm_ctrl_reg_mask); pm_ctrl_reg_mask_buf++; /* Increment buffer length trackers */ name_buf_len += strlen(states[i].name) + 1; num_supported_idle_states++; } /* Point buffer pointers back to beginning of the buffer */ name_buf -= name_buf_len; latency_ns_buf -= num_supported_idle_states; residency_ns_buf -= num_supported_idle_states; flags_buf -= num_supported_idle_states; pm_ctrl_reg_val_buf -= num_supported_idle_states; pm_ctrl_reg_mask_buf -= num_supported_idle_states; /* Create dt properties with the buffer content */ dt_add_property(power_mgt, "ibm,cpu-idle-state-names", name_buf, name_buf_len* sizeof(char)); dt_add_property(power_mgt, "ibm,cpu-idle-state-latencies-ns", latency_ns_buf, num_supported_idle_states * sizeof(u32)); dt_add_property(power_mgt, "ibm,cpu-idle-state-residency-ns", residency_ns_buf, num_supported_idle_states * sizeof(u32)); dt_add_property(power_mgt, "ibm,cpu-idle-state-flags", flags_buf, num_supported_idle_states * sizeof(u32)); if (has_stop_inst) { dt_add_property(power_mgt, "ibm,cpu-idle-state-psscr", pm_ctrl_reg_val_buf, num_supported_idle_states * sizeof(u64)); dt_add_property(power_mgt, "ibm,cpu-idle-state-psscr-mask", pm_ctrl_reg_mask_buf, num_supported_idle_states * sizeof(u64)); } else { dt_add_property(power_mgt, "ibm,cpu-idle-state-pmicr", pm_ctrl_reg_val_buf, num_supported_idle_states * sizeof(u64)); dt_add_property(power_mgt, "ibm,cpu-idle-state-pmicr-mask", pm_ctrl_reg_mask_buf, num_supported_idle_states * sizeof(u64)); } assert(alloced_name_buf == name_buf); free(alloced_name_buf); free(latency_ns_buf); free(residency_ns_buf); free(flags_buf); free(pm_ctrl_reg_val_buf); free(pm_ctrl_reg_mask_buf); } static void slw_cleanup_core(struct proc_chip *chip, struct cpu_thread *c) { uint64_t tmp; int rc; /* Display history to check transition */ rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(pir_to_core_id(c->pir), EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_GET), "SLW: Failed to read PM_IDLE_STATE_HISTORY\n"); /* XXX error handling ? return false; */ } prlog(PR_DEBUG, "SLW: core %x:%x history: 0x%016llx (new1)\n", chip->id, pir_to_core_id(c->pir), tmp); rc = xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(pir_to_core_id(c->pir), EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_GET), "SLW: Failed to read PM_IDLE_STATE_HISTORY\n"); /* XXX error handling ? return false; */ } prlog(PR_DEBUG, "SLW: core %x:%x history: 0x%016llx (new2)\n", chip->id, pir_to_core_id(c->pir), tmp); /* * XXX FIXME: Error out if the transition didn't reach rvwinkle ? */ /* * XXX FIXME: We should restore a bunch of the EX bits we * overwrite to sane values here */ slw_unset_overrides(chip, c); } static void slw_cleanup_chip(struct proc_chip *chip) { struct cpu_thread *c; for_each_available_core_in_chip(c, chip->id) slw_cleanup_core(chip, c); } static void slw_patch_scans(struct proc_chip *chip, bool le_mode) { int64_t rc; uint64_t old_val, new_val; rc = sbe_xip_get_scalar((void *)chip->slw_base, "skip_ex_override_ring_scans", &old_val); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_REG), "SLW: Failed to read scan override on chip %d\n", chip->id); return; } new_val = le_mode ? 0 : 1; prlog(PR_TRACE, "SLW: Chip %d, LE value was: %lld, setting to %lld\n", chip->id, old_val, new_val); rc = sbe_xip_set_scalar((void *)chip->slw_base, "skip_ex_override_ring_scans", new_val); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_REG), "SLW: Failed to set LE mode on chip %d\n", chip->id); return; } } int64_t slw_reinit(uint64_t flags) { struct proc_chip *chip; struct cpu_thread *cpu; bool has_waker = false; bool target_le = slw_current_le; if (proc_gen < proc_gen_p8) return OPAL_UNSUPPORTED; if (flags & OPAL_REINIT_CPUS_HILE_BE) target_le = false; if (flags & OPAL_REINIT_CPUS_HILE_LE) target_le = true; prlog(PR_TRACE, "SLW Reinit from CPU PIR 0x%04x," " HILE set to %s endian...\n", this_cpu()->pir, target_le ? "little" : "big"); /* Prepare chips/cores for rvwinkle */ for_each_chip(chip) { if (!chip->slw_base) { log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Not found on chip %d\n", chip->id); return OPAL_HARDWARE; } slw_patch_scans(chip, target_le); } slw_current_le = target_le; /* XXX Save HIDs ? Or do that in head.S ... */ slw_patch_reset(); /* rvwinkle everybody and pick one to wake me once I rvwinkle myself */ for_each_available_cpu(cpu) { struct cpu_thread *master = NULL; if (cpu == this_cpu()) continue; /* Pick up a waker for myself: it must not be a sibling of * the current CPU and must be a thread 0 (so it gets to * sync its timebase before doing time_wait_ms() */ if (!has_waker && !cpu_is_sibling(cpu, this_cpu()) && cpu_is_thread0(cpu)) { has_waker = true; master = this_cpu(); } __cpu_queue_job(cpu, "slw_do_rvwinkle", slw_do_rvwinkle, master, true); /* Wait for it to claim to be down */ while(cpu->state != cpu_state_rvwinkle) sync(); } /* XXX Wait one second ! (should check xscom state ? ) */ prlog(PR_TRACE, "SLW: Waiting one second...\n"); time_wait_ms(1000); prlog(PR_TRACE, "SLW: Done.\n"); for_each_chip(chip) { struct cpu_thread *c; uint64_t tmp; for_each_available_core_in_chip(c, chip->id) { xscom_read(chip->id, XSCOM_ADDR_P8_EX_SLAVE(pir_to_core_id(c->pir), EX_PM_IDLE_STATE_HISTORY_PHYP), &tmp); prlog(PR_DEBUG, "SLW: core %x:%x" " history: 0x%016llx (mid)\n", chip->id, pir_to_core_id(c->pir), tmp); } } /* Wake everybody except on my core */ for_each_cpu(cpu) { if (cpu->state != cpu_state_rvwinkle || cpu_is_sibling(cpu, this_cpu())) continue; icp_kick_cpu(cpu); /* Wait for it to claim to be back (XXX ADD TIMEOUT) */ while(cpu->state != cpu_state_active) sync(); } /* Did we find a waker ? If we didn't, that means we had no * other core in the system, we can't do it */ if (!has_waker) { prlog(PR_TRACE, "SLW: No candidate waker, giving up !\n"); return OPAL_HARDWARE; } /* Our siblings are rvwinkling, and our waker is waiting for us * so let's just go down now */ slw_do_rvwinkle(NULL); slw_unpatch_reset(); for_each_chip(chip) slw_cleanup_chip(chip); prlog(PR_TRACE, "SLW Reinit complete !\n"); return OPAL_SUCCESS; } static void slw_patch_regs(struct proc_chip *chip) { struct cpu_thread *c; void *image = (void *)chip->slw_base; int rc; for_each_available_cpu(c) { if (c->chip_id != chip->id) continue; /* Clear HRMOR */ rc = p8_pore_gen_cpureg_fixed(image, P8_SLW_MODEBUILD_SRAM, P8_SPR_HRMOR, 0, cpu_get_core_index(c), cpu_get_thread_index(c)); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_REG), "SLW: Failed to set HRMOR for CPU %x\n", c->pir); } /* XXX Add HIDs etc... */ } } static void slw_init_chip_p9(struct proc_chip *chip) { struct cpu_thread *c; prlog(PR_NOTICE, "SLW: Init chip 0x%x\n", chip->id); /* At power ON setup inits for power-mgt */ for_each_available_core_in_chip(c, chip->id) slw_set_overrides_p9(chip, c); } static void slw_init_chip(struct proc_chip *chip) { int64_t rc; struct cpu_thread *c; prlog(PR_DEBUG, "SLW: Init chip 0x%x\n", chip->id); if (!chip->slw_base) { prerror("SLW: No image found !\n"); return; } /* Check actual image size */ rc = sbe_xip_get_scalar((void *)chip->slw_base, "image_size", &chip->slw_image_size); if (rc != 0) { log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Error %lld reading SLW image size\n", rc); /* XXX Panic ? */ chip->slw_base = 0; chip->slw_bar_size = 0; chip->slw_image_size = 0; return; } prlog(PR_DEBUG, "SLW: Image size from image: 0x%llx\n", chip->slw_image_size); if (chip->slw_image_size > chip->slw_bar_size) { log_simple_error(&e_info(OPAL_RC_SLW_INIT), "SLW: Built-in image size larger than BAR size !\n"); /* XXX Panic ? */ } /* Patch SLW image */ slw_patch_regs(chip); /* At power ON setup inits for fast-sleep */ for_each_available_core_in_chip(c, chip->id) { idle_prepare_core(chip, c); } } /* Workarounds while entering fast-sleep */ static void fast_sleep_enter(void) { uint32_t core = pir_to_core_id(this_cpu()->pir); uint32_t chip_id = this_cpu()->chip_id; struct cpu_thread *primary_thread; uint64_t tmp; int rc; primary_thread = this_cpu()->primary; rc = xscom_read(chip_id, XSCOM_ADDR_P8_EX(core, L2_FIR_ACTION1), &tmp); if (rc) { prlog(PR_WARNING, "fast_sleep_enter XSCOM failed(1):" " rc=%d chip_id=%d core=%d\n", rc, chip_id, core); return; } primary_thread->save_l2_fir_action1 = tmp; primary_thread->in_fast_sleep = true; tmp = tmp & ~0x0200000000000000ULL; rc = xscom_write(chip_id, XSCOM_ADDR_P8_EX(core, L2_FIR_ACTION1), tmp); if (rc) { prlog(PR_WARNING, "fast_sleep_enter XSCOM failed(2):" " rc=%d chip_id=%d core=%d\n", rc, chip_id, core); return; } rc = xscom_read(chip_id, XSCOM_ADDR_P8_EX(core, L2_FIR_ACTION1), &tmp); if (rc) { prlog(PR_WARNING, "fast_sleep_enter XSCOM failed(3):" " rc=%d chip_id=%d core=%d\n", rc, chip_id, core); return; } } /* Workarounds while exiting fast-sleep */ void fast_sleep_exit(void) { uint32_t core = pir_to_core_id(this_cpu()->pir); uint32_t chip_id = this_cpu()->chip_id; struct cpu_thread *primary_thread; int rc; primary_thread = this_cpu()->primary; primary_thread->in_fast_sleep = false; rc = xscom_write(chip_id, XSCOM_ADDR_P8_EX(core, L2_FIR_ACTION1), primary_thread->save_l2_fir_action1); if (rc) { prlog(PR_WARNING, "fast_sleep_exit XSCOM failed:" " rc=%d chip_id=%d core=%d\n", rc, chip_id, core); return; } } /* * Setup and cleanup method for fast-sleep workarounds * state = 1 fast-sleep * enter = 1 Enter state * exit = 0 Exit state */ static int64_t opal_config_cpu_idle_state(uint64_t state, uint64_t enter) { /* Only fast-sleep for now */ if (state != 1) return OPAL_PARAMETER; switch(enter) { case 1: fast_sleep_enter(); break; case 0: fast_sleep_exit(); break; default: return OPAL_PARAMETER; } return OPAL_SUCCESS; } opal_call(OPAL_CONFIG_CPU_IDLE_STATE, opal_config_cpu_idle_state, 2); int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val) { struct cpu_thread *c = find_cpu_by_pir(cpu_pir); struct proc_chip *chip; void *image; int rc; int i; int spr_is_supported = 0; assert(c); chip = get_chip(c->chip_id); assert(chip); image = (void *) chip->slw_base; /* Check of the SPR is supported by libpore */ for ( i=0; i < SLW_SPR_REGS_SIZE ; i++) { if (sprn == SLW_SPR_REGS[i].value) { spr_is_supported = 1; break; } } if (!spr_is_supported) { log_simple_error(&e_info(OPAL_RC_SLW_REG), "SLW: Trying to set unsupported spr for CPU %x\n", c->pir); return OPAL_UNSUPPORTED; } rc = p8_pore_gen_cpureg_fixed(image, P8_SLW_MODEBUILD_SRAM, sprn, val, cpu_get_core_index(c), cpu_get_thread_index(c)); if (rc) { log_simple_error(&e_info(OPAL_RC_SLW_REG), "SLW: Failed to set spr for CPU %x\n", c->pir); return OPAL_INTERNAL_ERROR; } return OPAL_SUCCESS; } opal_call(OPAL_SLW_SET_REG, opal_slw_set_reg, 3); static void slw_dump_timer_ffdc(void) { uint64_t i, val; int64_t rc; static const uint32_t dump_regs[] = { 0xe0000, 0xe0001, 0xe0002, 0xe0003, 0xe0004, 0xe0005, 0xe0006, 0xe0007, 0xe0008, 0xe0009, 0xe000a, 0xe000b, 0xe000c, 0xe000d, 0xe000e, 0xe000f, 0xe0010, 0xe0011, 0xe0012, 0xe0013, 0xe0014, 0xe0015, 0xe0016, 0xe0017, 0xe0018, 0xe0019, 0x5001c, 0x50038, 0x50039, 0x5003a, 0x5003b }; /** * @fwts-label SLWRegisterDump * @fwts-advice An error condition occurred in sleep/winkle * engines timer state machine. Dumping debug information to * root-cause. OPAL/skiboot may be stuck on some operation that * requires SLW timer state machine (e.g. core powersaving) */ prlog(PR_DEBUG, "SLW: Register state:\n"); for (i = 0; i < ARRAY_SIZE(dump_regs); i++) { uint32_t reg = dump_regs[i]; rc = xscom_read(slw_timer_chip, reg, &val); if (rc) { prlog(PR_DEBUG, "SLW: XSCOM error %lld reading" " reg 0x%x\n", rc, reg); break; } prlog(PR_DEBUG, "SLW: %5x = %016llx\n", reg, val); } } /* This is called with the timer lock held, so there is no * issue with re-entrancy or concurrence */ void slw_update_timer_expiry(uint64_t new_target) { uint64_t count, gen, gen2, req, now = mftb(); int64_t rc; if (!slw_has_timer || new_target == slw_timer_target) return; slw_timer_target = new_target; /* Calculate how many increments from now, rounded up */ if (now < new_target) count = (new_target - now + slw_timer_inc - 1) / slw_timer_inc; else count = 1; /* Max counter is 24-bit */ if (count > 0xffffff) count = 0xffffff; /* Fabricate update request */ req = (1ull << 63) | (count << 32); prlog(PR_TRACE, "SLW: TMR expiry: 0x%llx, req: %016llx\n", count, req); do { /* Grab generation and spin if odd */ _xscom_lock(); for (;;) { rc = _xscom_read(slw_timer_chip, 0xE0006, &gen, false); if (rc) { prerror("SLW: Error %lld reading tmr gen " " count\n", rc); _xscom_unlock(); return; } if (!(gen & 1)) break; if (tb_compare(now + msecs_to_tb(1), mftb()) == TB_ABEFOREB) { /** * @fwts-label SLWTimerStuck * @fwts-advice The SLeep/Winkle Engine (SLW) * failed to increment the generation number * within our timeout period (it *should* have * done so within ~10us, not >1ms. OPAL uses * the SLW timer to schedule some operations, * but can fall back to the (much less frequent * OPAL poller, which although does not affect * functionality, runs *much* less frequently. * This could have the effect of slow I2C * operations (for example). It may also mean * that you *had* an increase in jitter, due * to slow interactions with SLW. * This error may also occur if the machine * is connected to via soft FSI. */ prerror("SLW: timer stuck, falling back to OPAL pollers. You will likely have slower I2C and may have experienced increased jitter.\n"); prlog(PR_DEBUG, "SLW: Stuck with odd generation !\n"); _xscom_unlock(); slw_has_timer = false; slw_dump_timer_ffdc(); return; } } rc = _xscom_write(slw_timer_chip, 0x5003A, req, false); if (rc) { prerror("SLW: Error %lld writing tmr request\n", rc); _xscom_unlock(); return; } /* Re-check gen count */ rc = _xscom_read(slw_timer_chip, 0xE0006, &gen2, false); if (rc) { prerror("SLW: Error %lld re-reading tmr gen " " count\n", rc); _xscom_unlock(); return; } _xscom_unlock(); } while(gen != gen2); /* Check if the timer is working. If at least 1ms has elapsed * since the last call to this function, check that the gen * count has changed */ if (tb_compare(slw_last_gen_stamp + msecs_to_tb(1), now) == TB_ABEFOREB) { if (slw_last_gen == gen) { prlog(PR_ERR, "SLW: Timer appears to not be running !\n"); slw_has_timer = false; slw_dump_timer_ffdc(); } slw_last_gen = gen; slw_last_gen_stamp = mftb(); } prlog(PR_TRACE, "SLW: gen: %llx\n", gen); } bool slw_timer_ok(void) { return slw_has_timer; } static void slw_init_timer(void) { struct dt_node *np; int64_t rc; uint32_t tick_us; np = dt_find_compatible_node(dt_root, NULL, "ibm,power8-sbe-timer"); if (!np) return; slw_timer_chip = dt_get_chip_id(np); tick_us = dt_prop_get_u32(np, "tick-time-us"); slw_timer_inc = usecs_to_tb(tick_us); slw_timer_target = ~0ull; rc = xscom_read(slw_timer_chip, 0xE0006, &slw_last_gen); if (rc) { prerror("SLW: Error %lld reading tmr gen count\n", rc); return; } slw_last_gen_stamp = mftb(); prlog(PR_INFO, "SLW: Timer facility on chip %d, resolution %dus\n", slw_timer_chip, tick_us); slw_has_timer = true; } void slw_init(void) { struct proc_chip *chip; if (proc_gen == proc_gen_p8) { for_each_chip(chip) slw_init_chip(chip); slw_init_timer(); } else if (proc_gen == proc_gen_p9) { for_each_chip(chip) slw_init_chip_p9(chip); } }