mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-27 00:45:13 +07:00
e9cef0189c
This is an implementation of commits53a712bae5
("powerpc/powernv/idle: Restore AMR/UAMOR/AMOR after idle") anda3f3072db6
("powerpc/powernv/idle: Restore IAMR after idle") using the new C-based idle code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Extract from Nick's patch] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
1404 lines
36 KiB
C
1404 lines
36 KiB
C
/*
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* PowerNV cpuidle code
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*
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* Copyright 2015 IBM Corp.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/of.h>
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#include <linux/device.h>
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#include <linux/cpu.h>
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#include <asm/asm-prototypes.h>
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#include <asm/firmware.h>
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#include <asm/machdep.h>
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#include <asm/opal.h>
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#include <asm/cputhreads.h>
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#include <asm/cpuidle.h>
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#include <asm/code-patching.h>
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#include <asm/smp.h>
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#include <asm/runlatch.h>
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#include <asm/dbell.h>
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#include "powernv.h"
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#include "subcore.h"
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/* Power ISA 3.0 allows for stop states 0x0 - 0xF */
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#define MAX_STOP_STATE 0xF
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#define P9_STOP_SPR_MSR 2000
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#define P9_STOP_SPR_PSSCR 855
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static u32 supported_cpuidle_states;
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struct pnv_idle_states_t *pnv_idle_states;
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int nr_pnv_idle_states;
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/*
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* The default stop state that will be used by ppc_md.power_save
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* function on platforms that support stop instruction.
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*/
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static u64 pnv_default_stop_val;
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static u64 pnv_default_stop_mask;
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static bool default_stop_found;
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/*
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* First stop state levels when SPR and TB loss can occur.
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*/
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static u64 pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
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static u64 pnv_first_spr_loss_level = MAX_STOP_STATE + 1;
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/*
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* psscr value and mask of the deepest stop idle state.
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* Used when a cpu is offlined.
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*/
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static u64 pnv_deepest_stop_psscr_val;
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static u64 pnv_deepest_stop_psscr_mask;
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static u64 pnv_deepest_stop_flag;
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static bool deepest_stop_found;
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static unsigned long power7_offline_type;
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static int pnv_save_sprs_for_deep_states(void)
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{
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int cpu;
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int rc;
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/*
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* hid0, hid1, hid4, hid5, hmeer and lpcr values are symmetric across
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* all cpus at boot. Get these reg values of current cpu and use the
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* same across all cpus.
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*/
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uint64_t lpcr_val = mfspr(SPRN_LPCR);
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uint64_t hid0_val = mfspr(SPRN_HID0);
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uint64_t hid1_val = mfspr(SPRN_HID1);
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uint64_t hid4_val = mfspr(SPRN_HID4);
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uint64_t hid5_val = mfspr(SPRN_HID5);
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uint64_t hmeer_val = mfspr(SPRN_HMEER);
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uint64_t msr_val = MSR_IDLE;
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uint64_t psscr_val = pnv_deepest_stop_psscr_val;
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for_each_present_cpu(cpu) {
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uint64_t pir = get_hard_smp_processor_id(cpu);
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uint64_t hsprg0_val = (uint64_t)paca_ptrs[cpu];
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rc = opal_slw_set_reg(pir, SPRN_HSPRG0, hsprg0_val);
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if (rc != 0)
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return rc;
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rc = opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val);
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if (rc != 0)
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return rc;
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if (cpu_has_feature(CPU_FTR_ARCH_300)) {
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rc = opal_slw_set_reg(pir, P9_STOP_SPR_MSR, msr_val);
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if (rc)
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return rc;
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rc = opal_slw_set_reg(pir,
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P9_STOP_SPR_PSSCR, psscr_val);
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if (rc)
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return rc;
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}
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/* HIDs are per core registers */
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if (cpu_thread_in_core(cpu) == 0) {
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rc = opal_slw_set_reg(pir, SPRN_HMEER, hmeer_val);
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if (rc != 0)
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return rc;
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rc = opal_slw_set_reg(pir, SPRN_HID0, hid0_val);
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if (rc != 0)
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return rc;
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/* Only p8 needs to set extra HID regiters */
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if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
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rc = opal_slw_set_reg(pir, SPRN_HID1, hid1_val);
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if (rc != 0)
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return rc;
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rc = opal_slw_set_reg(pir, SPRN_HID4, hid4_val);
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if (rc != 0)
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return rc;
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rc = opal_slw_set_reg(pir, SPRN_HID5, hid5_val);
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if (rc != 0)
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return rc;
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}
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}
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}
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return 0;
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}
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u32 pnv_get_supported_cpuidle_states(void)
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{
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return supported_cpuidle_states;
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}
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EXPORT_SYMBOL_GPL(pnv_get_supported_cpuidle_states);
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static void pnv_fastsleep_workaround_apply(void *info)
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{
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int rc;
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int *err = info;
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rc = opal_config_cpu_idle_state(OPAL_CONFIG_IDLE_FASTSLEEP,
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OPAL_CONFIG_IDLE_APPLY);
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if (rc)
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*err = 1;
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}
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static bool power7_fastsleep_workaround_entry = true;
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static bool power7_fastsleep_workaround_exit = true;
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/*
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* Used to store fastsleep workaround state
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* 0 - Workaround applied/undone at fastsleep entry/exit path (Default)
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* 1 - Workaround applied once, never undone.
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*/
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static u8 fastsleep_workaround_applyonce;
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static ssize_t show_fastsleep_workaround_applyonce(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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return sprintf(buf, "%u\n", fastsleep_workaround_applyonce);
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}
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static ssize_t store_fastsleep_workaround_applyonce(struct device *dev,
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struct device_attribute *attr, const char *buf,
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size_t count)
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{
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cpumask_t primary_thread_mask;
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int err;
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u8 val;
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if (kstrtou8(buf, 0, &val) || val != 1)
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return -EINVAL;
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if (fastsleep_workaround_applyonce == 1)
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return count;
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/*
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* fastsleep_workaround_applyonce = 1 implies
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* fastsleep workaround needs to be left in 'applied' state on all
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* the cores. Do this by-
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* 1. Disable the 'undo' workaround in fastsleep exit path
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* 2. Sendi IPIs to all the cores which have at least one online thread
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* 3. Disable the 'apply' workaround in fastsleep entry path
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*
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* There is no need to send ipi to cores which have all threads
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* offlined, as last thread of the core entering fastsleep or deeper
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* state would have applied workaround.
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*/
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power7_fastsleep_workaround_exit = false;
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get_online_cpus();
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primary_thread_mask = cpu_online_cores_map();
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on_each_cpu_mask(&primary_thread_mask,
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pnv_fastsleep_workaround_apply,
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&err, 1);
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put_online_cpus();
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if (err) {
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pr_err("fastsleep_workaround_applyonce change failed while running pnv_fastsleep_workaround_apply");
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goto fail;
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}
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power7_fastsleep_workaround_entry = false;
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fastsleep_workaround_applyonce = 1;
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return count;
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fail:
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return -EIO;
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}
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static DEVICE_ATTR(fastsleep_workaround_applyonce, 0600,
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show_fastsleep_workaround_applyonce,
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store_fastsleep_workaround_applyonce);
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static inline void atomic_start_thread_idle(void)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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int thread_nr = cpu_thread_in_core(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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clear_bit(thread_nr, state);
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}
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static inline void atomic_stop_thread_idle(void)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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int thread_nr = cpu_thread_in_core(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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set_bit(thread_nr, state);
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}
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static inline void atomic_lock_thread_idle(void)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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while (unlikely(test_and_set_bit_lock(NR_PNV_CORE_IDLE_LOCK_BIT, state)))
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barrier();
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}
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static inline void atomic_unlock_and_stop_thread_idle(void)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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unsigned long thread = 1UL << cpu_thread_in_core(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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u64 s = READ_ONCE(*state);
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u64 new, tmp;
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BUG_ON(!(s & PNV_CORE_IDLE_LOCK_BIT));
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BUG_ON(s & thread);
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again:
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new = (s | thread) & ~PNV_CORE_IDLE_LOCK_BIT;
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tmp = cmpxchg(state, s, new);
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if (unlikely(tmp != s)) {
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s = tmp;
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goto again;
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}
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}
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static inline void atomic_unlock_thread_idle(void)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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BUG_ON(!test_bit(NR_PNV_CORE_IDLE_LOCK_BIT, state));
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clear_bit_unlock(NR_PNV_CORE_IDLE_LOCK_BIT, state);
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}
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/* P7 and P8 */
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struct p7_sprs {
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/* per core */
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u64 tscr;
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u64 worc;
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/* per subcore */
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u64 sdr1;
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u64 rpr;
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/* per thread */
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u64 lpcr;
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u64 hfscr;
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u64 fscr;
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u64 purr;
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u64 spurr;
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u64 dscr;
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u64 wort;
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/* per thread SPRs that get lost in shallow states */
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u64 amr;
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u64 iamr;
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u64 amor;
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u64 uamor;
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};
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static unsigned long power7_idle_insn(unsigned long type)
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{
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int cpu = raw_smp_processor_id();
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int first = cpu_first_thread_sibling(cpu);
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unsigned long *state = &paca_ptrs[first]->idle_state;
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unsigned long thread = 1UL << cpu_thread_in_core(cpu);
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unsigned long core_thread_mask = (1UL << threads_per_core) - 1;
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unsigned long srr1;
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bool full_winkle;
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struct p7_sprs sprs = {}; /* avoid false use-uninitialised */
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bool sprs_saved = false;
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int rc;
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if (unlikely(type != PNV_THREAD_NAP)) {
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atomic_lock_thread_idle();
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BUG_ON(!(*state & thread));
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*state &= ~thread;
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if (power7_fastsleep_workaround_entry) {
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if ((*state & core_thread_mask) == 0) {
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rc = opal_config_cpu_idle_state(
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OPAL_CONFIG_IDLE_FASTSLEEP,
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OPAL_CONFIG_IDLE_APPLY);
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BUG_ON(rc);
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}
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}
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if (type == PNV_THREAD_WINKLE) {
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sprs.tscr = mfspr(SPRN_TSCR);
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sprs.worc = mfspr(SPRN_WORC);
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sprs.sdr1 = mfspr(SPRN_SDR1);
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sprs.rpr = mfspr(SPRN_RPR);
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sprs.lpcr = mfspr(SPRN_LPCR);
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if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
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sprs.hfscr = mfspr(SPRN_HFSCR);
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sprs.fscr = mfspr(SPRN_FSCR);
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}
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sprs.purr = mfspr(SPRN_PURR);
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sprs.spurr = mfspr(SPRN_SPURR);
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sprs.dscr = mfspr(SPRN_DSCR);
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sprs.wort = mfspr(SPRN_WORT);
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sprs_saved = true;
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/*
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* Increment winkle counter and set all winkle bits if
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* all threads are winkling. This allows wakeup side to
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* distinguish between fast sleep and winkle state
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* loss. Fast sleep still has to resync the timebase so
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* this may not be a really big win.
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*/
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*state += 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT;
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if ((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS)
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>> PNV_CORE_IDLE_WINKLE_COUNT_SHIFT
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== threads_per_core)
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*state |= PNV_CORE_IDLE_THREAD_WINKLE_BITS;
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WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0);
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}
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|
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atomic_unlock_thread_idle();
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}
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|
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if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
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sprs.amr = mfspr(SPRN_AMR);
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sprs.iamr = mfspr(SPRN_IAMR);
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sprs.amor = mfspr(SPRN_AMOR);
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sprs.uamor = mfspr(SPRN_UAMOR);
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}
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local_paca->thread_idle_state = type;
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srr1 = isa206_idle_insn_mayloss(type); /* go idle */
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local_paca->thread_idle_state = PNV_THREAD_RUNNING;
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|
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WARN_ON_ONCE(!srr1);
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WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR));
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|
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if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
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if ((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS) {
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/*
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* We don't need an isync after the mtsprs here because
|
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* the upcoming mtmsrd is execution synchronizing.
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*/
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mtspr(SPRN_AMR, sprs.amr);
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mtspr(SPRN_IAMR, sprs.iamr);
|
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mtspr(SPRN_AMOR, sprs.amor);
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mtspr(SPRN_UAMOR, sprs.uamor);
|
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}
|
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}
|
|
|
|
if (unlikely((srr1 & SRR1_WAKEMASK_P8) == SRR1_WAKEHMI))
|
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hmi_exception_realmode(NULL);
|
|
|
|
if (likely((srr1 & SRR1_WAKESTATE) != SRR1_WS_HVLOSS)) {
|
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if (unlikely(type != PNV_THREAD_NAP)) {
|
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atomic_lock_thread_idle();
|
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if (type == PNV_THREAD_WINKLE) {
|
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WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0);
|
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*state -= 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT;
|
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*state &= ~(thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT);
|
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}
|
|
atomic_unlock_and_stop_thread_idle();
|
|
}
|
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return srr1;
|
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}
|
|
|
|
/* HV state loss */
|
|
BUG_ON(type == PNV_THREAD_NAP);
|
|
|
|
atomic_lock_thread_idle();
|
|
|
|
full_winkle = false;
|
|
if (type == PNV_THREAD_WINKLE) {
|
|
WARN_ON((*state & PNV_CORE_IDLE_WINKLE_COUNT_BITS) == 0);
|
|
*state -= 1 << PNV_CORE_IDLE_WINKLE_COUNT_SHIFT;
|
|
if (*state & (thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT)) {
|
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*state &= ~(thread << PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT);
|
|
full_winkle = true;
|
|
BUG_ON(!sprs_saved);
|
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}
|
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}
|
|
|
|
WARN_ON(*state & thread);
|
|
|
|
if ((*state & core_thread_mask) != 0)
|
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goto core_woken;
|
|
|
|
/* Per-core SPRs */
|
|
if (full_winkle) {
|
|
mtspr(SPRN_TSCR, sprs.tscr);
|
|
mtspr(SPRN_WORC, sprs.worc);
|
|
}
|
|
|
|
if (power7_fastsleep_workaround_exit) {
|
|
rc = opal_config_cpu_idle_state(OPAL_CONFIG_IDLE_FASTSLEEP,
|
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OPAL_CONFIG_IDLE_UNDO);
|
|
BUG_ON(rc);
|
|
}
|
|
|
|
/* TB */
|
|
if (opal_resync_timebase() != OPAL_SUCCESS)
|
|
BUG();
|
|
|
|
core_woken:
|
|
if (!full_winkle)
|
|
goto subcore_woken;
|
|
|
|
if ((*state & local_paca->subcore_sibling_mask) != 0)
|
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goto subcore_woken;
|
|
|
|
/* Per-subcore SPRs */
|
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mtspr(SPRN_SDR1, sprs.sdr1);
|
|
mtspr(SPRN_RPR, sprs.rpr);
|
|
|
|
subcore_woken:
|
|
/*
|
|
* isync after restoring shared SPRs and before unlocking. Unlock
|
|
* only contains hwsync which does not necessarily do the right
|
|
* thing for SPRs.
|
|
*/
|
|
isync();
|
|
atomic_unlock_and_stop_thread_idle();
|
|
|
|
/* Fast sleep does not lose SPRs */
|
|
if (!full_winkle)
|
|
return srr1;
|
|
|
|
/* Per-thread SPRs */
|
|
mtspr(SPRN_LPCR, sprs.lpcr);
|
|
if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
|
|
mtspr(SPRN_HFSCR, sprs.hfscr);
|
|
mtspr(SPRN_FSCR, sprs.fscr);
|
|
}
|
|
mtspr(SPRN_PURR, sprs.purr);
|
|
mtspr(SPRN_SPURR, sprs.spurr);
|
|
mtspr(SPRN_DSCR, sprs.dscr);
|
|
mtspr(SPRN_WORT, sprs.wort);
|
|
|
|
mtspr(SPRN_SPRG3, local_paca->sprg_vdso);
|
|
|
|
/*
|
|
* The SLB has to be restored here, but it sometimes still
|
|
* contains entries, so the __ variant must be used to prevent
|
|
* multi hits.
|
|
*/
|
|
__slb_restore_bolted_realmode();
|
|
|
|
return srr1;
|
|
}
|
|
|
|
extern unsigned long idle_kvm_start_guest(unsigned long srr1);
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static unsigned long power7_offline(void)
|
|
{
|
|
unsigned long srr1;
|
|
|
|
mtmsr(MSR_IDLE);
|
|
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
/* Tell KVM we're entering idle. */
|
|
/******************************************************/
|
|
/* N O T E W E L L ! ! ! N O T E W E L L */
|
|
/* The following store to HSTATE_HWTHREAD_STATE(r13) */
|
|
/* MUST occur in real mode, i.e. with the MMU off, */
|
|
/* and the MMU must stay off until we clear this flag */
|
|
/* and test HSTATE_HWTHREAD_REQ(r13) in */
|
|
/* pnv_powersave_wakeup in this file. */
|
|
/* The reason is that another thread can switch the */
|
|
/* MMU to a guest context whenever this flag is set */
|
|
/* to KVM_HWTHREAD_IN_IDLE, and if the MMU was on, */
|
|
/* that would potentially cause this thread to start */
|
|
/* executing instructions from guest memory in */
|
|
/* hypervisor mode, leading to a host crash or data */
|
|
/* corruption, or worse. */
|
|
/******************************************************/
|
|
local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE;
|
|
#endif
|
|
|
|
__ppc64_runlatch_off();
|
|
srr1 = power7_idle_insn(power7_offline_type);
|
|
__ppc64_runlatch_on();
|
|
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_KERNEL;
|
|
/* Order setting hwthread_state vs. testing hwthread_req */
|
|
smp_mb();
|
|
if (local_paca->kvm_hstate.hwthread_req)
|
|
srr1 = idle_kvm_start_guest(srr1);
|
|
#endif
|
|
|
|
mtmsr(MSR_KERNEL);
|
|
|
|
return srr1;
|
|
}
|
|
#endif
|
|
|
|
void power7_idle_type(unsigned long type)
|
|
{
|
|
unsigned long srr1;
|
|
|
|
if (!prep_irq_for_idle_irqsoff())
|
|
return;
|
|
|
|
mtmsr(MSR_IDLE);
|
|
__ppc64_runlatch_off();
|
|
srr1 = power7_idle_insn(type);
|
|
__ppc64_runlatch_on();
|
|
mtmsr(MSR_KERNEL);
|
|
|
|
fini_irq_for_idle_irqsoff();
|
|
irq_set_pending_from_srr1(srr1);
|
|
}
|
|
|
|
void power7_idle(void)
|
|
{
|
|
if (!powersave_nap)
|
|
return;
|
|
|
|
power7_idle_type(PNV_THREAD_NAP);
|
|
}
|
|
|
|
struct p9_sprs {
|
|
/* per core */
|
|
u64 ptcr;
|
|
u64 rpr;
|
|
u64 tscr;
|
|
u64 ldbar;
|
|
|
|
/* per thread */
|
|
u64 lpcr;
|
|
u64 hfscr;
|
|
u64 fscr;
|
|
u64 pid;
|
|
u64 purr;
|
|
u64 spurr;
|
|
u64 dscr;
|
|
u64 wort;
|
|
|
|
u64 mmcra;
|
|
u32 mmcr0;
|
|
u32 mmcr1;
|
|
u64 mmcr2;
|
|
|
|
/* per thread SPRs that get lost in shallow states */
|
|
u64 amr;
|
|
u64 iamr;
|
|
u64 amor;
|
|
u64 uamor;
|
|
};
|
|
|
|
static unsigned long power9_idle_stop(unsigned long psscr, bool mmu_on)
|
|
{
|
|
int cpu = raw_smp_processor_id();
|
|
int first = cpu_first_thread_sibling(cpu);
|
|
unsigned long *state = &paca_ptrs[first]->idle_state;
|
|
unsigned long core_thread_mask = (1UL << threads_per_core) - 1;
|
|
unsigned long srr1;
|
|
unsigned long pls;
|
|
unsigned long mmcr0 = 0;
|
|
struct p9_sprs sprs = {}; /* avoid false used-uninitialised */
|
|
bool sprs_saved = false;
|
|
|
|
if (!(psscr & (PSSCR_EC|PSSCR_ESL))) {
|
|
/* EC=ESL=0 case */
|
|
|
|
BUG_ON(!mmu_on);
|
|
|
|
/*
|
|
* Wake synchronously. SRESET via xscom may still cause
|
|
* a 0x100 powersave wakeup with SRR1 reason!
|
|
*/
|
|
srr1 = isa300_idle_stop_noloss(psscr); /* go idle */
|
|
if (likely(!srr1))
|
|
return 0;
|
|
|
|
/*
|
|
* Registers not saved, can't recover!
|
|
* This would be a hardware bug
|
|
*/
|
|
BUG_ON((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS);
|
|
|
|
goto out;
|
|
}
|
|
|
|
/* EC=ESL=1 case */
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
if (cpu_has_feature(CPU_FTR_P9_TM_XER_SO_BUG)) {
|
|
local_paca->requested_psscr = psscr;
|
|
/* order setting requested_psscr vs testing dont_stop */
|
|
smp_mb();
|
|
if (atomic_read(&local_paca->dont_stop)) {
|
|
local_paca->requested_psscr = 0;
|
|
return 0;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!cpu_has_feature(CPU_FTR_POWER9_DD2_1)) {
|
|
/*
|
|
* POWER9 DD2 can incorrectly set PMAO when waking up
|
|
* after a state-loss idle. Saving and restoring MMCR0
|
|
* over idle is a workaround.
|
|
*/
|
|
mmcr0 = mfspr(SPRN_MMCR0);
|
|
}
|
|
if ((psscr & PSSCR_RL_MASK) >= pnv_first_spr_loss_level) {
|
|
sprs.lpcr = mfspr(SPRN_LPCR);
|
|
sprs.hfscr = mfspr(SPRN_HFSCR);
|
|
sprs.fscr = mfspr(SPRN_FSCR);
|
|
sprs.pid = mfspr(SPRN_PID);
|
|
sprs.purr = mfspr(SPRN_PURR);
|
|
sprs.spurr = mfspr(SPRN_SPURR);
|
|
sprs.dscr = mfspr(SPRN_DSCR);
|
|
sprs.wort = mfspr(SPRN_WORT);
|
|
|
|
sprs.mmcra = mfspr(SPRN_MMCRA);
|
|
sprs.mmcr0 = mfspr(SPRN_MMCR0);
|
|
sprs.mmcr1 = mfspr(SPRN_MMCR1);
|
|
sprs.mmcr2 = mfspr(SPRN_MMCR2);
|
|
|
|
sprs.ptcr = mfspr(SPRN_PTCR);
|
|
sprs.rpr = mfspr(SPRN_RPR);
|
|
sprs.tscr = mfspr(SPRN_TSCR);
|
|
sprs.ldbar = mfspr(SPRN_LDBAR);
|
|
|
|
sprs_saved = true;
|
|
|
|
atomic_start_thread_idle();
|
|
}
|
|
|
|
sprs.amr = mfspr(SPRN_AMR);
|
|
sprs.iamr = mfspr(SPRN_IAMR);
|
|
sprs.amor = mfspr(SPRN_AMOR);
|
|
sprs.uamor = mfspr(SPRN_UAMOR);
|
|
|
|
srr1 = isa300_idle_stop_mayloss(psscr); /* go idle */
|
|
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
local_paca->requested_psscr = 0;
|
|
#endif
|
|
|
|
psscr = mfspr(SPRN_PSSCR);
|
|
|
|
WARN_ON_ONCE(!srr1);
|
|
WARN_ON_ONCE(mfmsr() & (MSR_IR|MSR_DR));
|
|
|
|
if ((srr1 & SRR1_WAKESTATE) != SRR1_WS_NOLOSS) {
|
|
unsigned long mmcra;
|
|
|
|
/*
|
|
* We don't need an isync after the mtsprs here because the
|
|
* upcoming mtmsrd is execution synchronizing.
|
|
*/
|
|
mtspr(SPRN_AMR, sprs.amr);
|
|
mtspr(SPRN_IAMR, sprs.iamr);
|
|
mtspr(SPRN_AMOR, sprs.amor);
|
|
mtspr(SPRN_UAMOR, sprs.uamor);
|
|
|
|
/*
|
|
* Workaround for POWER9 DD2.0, if we lost resources, the ERAT
|
|
* might have been corrupted and needs flushing. We also need
|
|
* to reload MMCR0 (see mmcr0 comment above).
|
|
*/
|
|
if (!cpu_has_feature(CPU_FTR_POWER9_DD2_1)) {
|
|
asm volatile(PPC_INVALIDATE_ERAT);
|
|
mtspr(SPRN_MMCR0, mmcr0);
|
|
}
|
|
|
|
/*
|
|
* DD2.2 and earlier need to set then clear bit 60 in MMCRA
|
|
* to ensure the PMU starts running.
|
|
*/
|
|
mmcra = mfspr(SPRN_MMCRA);
|
|
mmcra |= PPC_BIT(60);
|
|
mtspr(SPRN_MMCRA, mmcra);
|
|
mmcra &= ~PPC_BIT(60);
|
|
mtspr(SPRN_MMCRA, mmcra);
|
|
}
|
|
|
|
if (unlikely((srr1 & SRR1_WAKEMASK_P8) == SRR1_WAKEHMI))
|
|
hmi_exception_realmode(NULL);
|
|
|
|
/*
|
|
* On POWER9, SRR1 bits do not match exactly as expected.
|
|
* SRR1_WS_GPRLOSS (10b) can also result in SPR loss, so
|
|
* just always test PSSCR for SPR/TB state loss.
|
|
*/
|
|
pls = (psscr & PSSCR_PLS) >> PSSCR_PLS_SHIFT;
|
|
if (likely(pls < pnv_first_spr_loss_level)) {
|
|
if (sprs_saved)
|
|
atomic_stop_thread_idle();
|
|
goto out;
|
|
}
|
|
|
|
/* HV state loss */
|
|
BUG_ON(!sprs_saved);
|
|
|
|
atomic_lock_thread_idle();
|
|
|
|
if ((*state & core_thread_mask) != 0)
|
|
goto core_woken;
|
|
|
|
/* Per-core SPRs */
|
|
mtspr(SPRN_PTCR, sprs.ptcr);
|
|
mtspr(SPRN_RPR, sprs.rpr);
|
|
mtspr(SPRN_TSCR, sprs.tscr);
|
|
mtspr(SPRN_LDBAR, sprs.ldbar);
|
|
|
|
if (pls >= pnv_first_tb_loss_level) {
|
|
/* TB loss */
|
|
if (opal_resync_timebase() != OPAL_SUCCESS)
|
|
BUG();
|
|
}
|
|
|
|
/*
|
|
* isync after restoring shared SPRs and before unlocking. Unlock
|
|
* only contains hwsync which does not necessarily do the right
|
|
* thing for SPRs.
|
|
*/
|
|
isync();
|
|
|
|
core_woken:
|
|
atomic_unlock_and_stop_thread_idle();
|
|
|
|
/* Per-thread SPRs */
|
|
mtspr(SPRN_LPCR, sprs.lpcr);
|
|
mtspr(SPRN_HFSCR, sprs.hfscr);
|
|
mtspr(SPRN_FSCR, sprs.fscr);
|
|
mtspr(SPRN_PID, sprs.pid);
|
|
mtspr(SPRN_PURR, sprs.purr);
|
|
mtspr(SPRN_SPURR, sprs.spurr);
|
|
mtspr(SPRN_DSCR, sprs.dscr);
|
|
mtspr(SPRN_WORT, sprs.wort);
|
|
|
|
mtspr(SPRN_MMCRA, sprs.mmcra);
|
|
mtspr(SPRN_MMCR0, sprs.mmcr0);
|
|
mtspr(SPRN_MMCR1, sprs.mmcr1);
|
|
mtspr(SPRN_MMCR2, sprs.mmcr2);
|
|
|
|
mtspr(SPRN_SPRG3, local_paca->sprg_vdso);
|
|
|
|
if (!radix_enabled())
|
|
__slb_restore_bolted_realmode();
|
|
|
|
out:
|
|
if (mmu_on)
|
|
mtmsr(MSR_KERNEL);
|
|
|
|
return srr1;
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
static unsigned long power9_offline_stop(unsigned long psscr)
|
|
{
|
|
unsigned long srr1;
|
|
|
|
#ifndef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
__ppc64_runlatch_off();
|
|
srr1 = power9_idle_stop(psscr, true);
|
|
__ppc64_runlatch_on();
|
|
#else
|
|
/*
|
|
* Tell KVM we're entering idle.
|
|
* This does not have to be done in real mode because the P9 MMU
|
|
* is independent per-thread. Some steppings share radix/hash mode
|
|
* between threads, but in that case KVM has a barrier sync in real
|
|
* mode before and after switching between radix and hash.
|
|
*
|
|
* kvm_start_guest must still be called in real mode though, hence
|
|
* the false argument.
|
|
*/
|
|
local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_IDLE;
|
|
|
|
__ppc64_runlatch_off();
|
|
srr1 = power9_idle_stop(psscr, false);
|
|
__ppc64_runlatch_on();
|
|
|
|
local_paca->kvm_hstate.hwthread_state = KVM_HWTHREAD_IN_KERNEL;
|
|
/* Order setting hwthread_state vs. testing hwthread_req */
|
|
smp_mb();
|
|
if (local_paca->kvm_hstate.hwthread_req)
|
|
srr1 = idle_kvm_start_guest(srr1);
|
|
mtmsr(MSR_KERNEL);
|
|
#endif
|
|
|
|
return srr1;
|
|
}
|
|
#endif
|
|
|
|
void power9_idle_type(unsigned long stop_psscr_val,
|
|
unsigned long stop_psscr_mask)
|
|
{
|
|
unsigned long psscr;
|
|
unsigned long srr1;
|
|
|
|
if (!prep_irq_for_idle_irqsoff())
|
|
return;
|
|
|
|
psscr = mfspr(SPRN_PSSCR);
|
|
psscr = (psscr & ~stop_psscr_mask) | stop_psscr_val;
|
|
|
|
__ppc64_runlatch_off();
|
|
srr1 = power9_idle_stop(psscr, true);
|
|
__ppc64_runlatch_on();
|
|
|
|
fini_irq_for_idle_irqsoff();
|
|
|
|
irq_set_pending_from_srr1(srr1);
|
|
}
|
|
|
|
/*
|
|
* Used for ppc_md.power_save which needs a function with no parameters
|
|
*/
|
|
void power9_idle(void)
|
|
{
|
|
power9_idle_type(pnv_default_stop_val, pnv_default_stop_mask);
|
|
}
|
|
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
/*
|
|
* This is used in working around bugs in thread reconfiguration
|
|
* on POWER9 (at least up to Nimbus DD2.2) relating to transactional
|
|
* memory and the way that XER[SO] is checkpointed.
|
|
* This function forces the core into SMT4 in order by asking
|
|
* all other threads not to stop, and sending a message to any
|
|
* that are in a stop state.
|
|
* Must be called with preemption disabled.
|
|
*/
|
|
void pnv_power9_force_smt4_catch(void)
|
|
{
|
|
int cpu, cpu0, thr;
|
|
int awake_threads = 1; /* this thread is awake */
|
|
int poke_threads = 0;
|
|
int need_awake = threads_per_core;
|
|
|
|
cpu = smp_processor_id();
|
|
cpu0 = cpu & ~(threads_per_core - 1);
|
|
for (thr = 0; thr < threads_per_core; ++thr) {
|
|
if (cpu != cpu0 + thr)
|
|
atomic_inc(&paca_ptrs[cpu0+thr]->dont_stop);
|
|
}
|
|
/* order setting dont_stop vs testing requested_psscr */
|
|
smp_mb();
|
|
for (thr = 0; thr < threads_per_core; ++thr) {
|
|
if (!paca_ptrs[cpu0+thr]->requested_psscr)
|
|
++awake_threads;
|
|
else
|
|
poke_threads |= (1 << thr);
|
|
}
|
|
|
|
/* If at least 3 threads are awake, the core is in SMT4 already */
|
|
if (awake_threads < need_awake) {
|
|
/* We have to wake some threads; we'll use msgsnd */
|
|
for (thr = 0; thr < threads_per_core; ++thr) {
|
|
if (poke_threads & (1 << thr)) {
|
|
ppc_msgsnd_sync();
|
|
ppc_msgsnd(PPC_DBELL_MSGTYPE, 0,
|
|
paca_ptrs[cpu0+thr]->hw_cpu_id);
|
|
}
|
|
}
|
|
/* now spin until at least 3 threads are awake */
|
|
do {
|
|
for (thr = 0; thr < threads_per_core; ++thr) {
|
|
if ((poke_threads & (1 << thr)) &&
|
|
!paca_ptrs[cpu0+thr]->requested_psscr) {
|
|
++awake_threads;
|
|
poke_threads &= ~(1 << thr);
|
|
}
|
|
}
|
|
} while (awake_threads < need_awake);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(pnv_power9_force_smt4_catch);
|
|
|
|
void pnv_power9_force_smt4_release(void)
|
|
{
|
|
int cpu, cpu0, thr;
|
|
|
|
cpu = smp_processor_id();
|
|
cpu0 = cpu & ~(threads_per_core - 1);
|
|
|
|
/* clear all the dont_stop flags */
|
|
for (thr = 0; thr < threads_per_core; ++thr) {
|
|
if (cpu != cpu0 + thr)
|
|
atomic_dec(&paca_ptrs[cpu0+thr]->dont_stop);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(pnv_power9_force_smt4_release);
|
|
#endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
|
|
void pnv_program_cpu_hotplug_lpcr(unsigned int cpu, u64 lpcr_val)
|
|
{
|
|
u64 pir = get_hard_smp_processor_id(cpu);
|
|
|
|
mtspr(SPRN_LPCR, lpcr_val);
|
|
|
|
/*
|
|
* Program the LPCR via stop-api only if the deepest stop state
|
|
* can lose hypervisor context.
|
|
*/
|
|
if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT)
|
|
opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val);
|
|
}
|
|
|
|
/*
|
|
* pnv_cpu_offline: A function that puts the CPU into the deepest
|
|
* available platform idle state on a CPU-Offline.
|
|
* interrupts hard disabled and no lazy irq pending.
|
|
*/
|
|
unsigned long pnv_cpu_offline(unsigned int cpu)
|
|
{
|
|
unsigned long srr1;
|
|
|
|
__ppc64_runlatch_off();
|
|
|
|
if (cpu_has_feature(CPU_FTR_ARCH_300) && deepest_stop_found) {
|
|
unsigned long psscr;
|
|
|
|
psscr = mfspr(SPRN_PSSCR);
|
|
psscr = (psscr & ~pnv_deepest_stop_psscr_mask) |
|
|
pnv_deepest_stop_psscr_val;
|
|
srr1 = power9_offline_stop(psscr);
|
|
} else if (cpu_has_feature(CPU_FTR_ARCH_206) && power7_offline_type) {
|
|
srr1 = power7_offline();
|
|
} else {
|
|
/* This is the fallback method. We emulate snooze */
|
|
while (!generic_check_cpu_restart(cpu)) {
|
|
HMT_low();
|
|
HMT_very_low();
|
|
}
|
|
srr1 = 0;
|
|
HMT_medium();
|
|
}
|
|
|
|
__ppc64_runlatch_on();
|
|
|
|
return srr1;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Power ISA 3.0 idle initialization.
|
|
*
|
|
* POWER ISA 3.0 defines a new SPR Processor stop Status and Control
|
|
* Register (PSSCR) to control idle behavior.
|
|
*
|
|
* PSSCR layout:
|
|
* ----------------------------------------------------------
|
|
* | PLS | /// | SD | ESL | EC | PSLL | /// | TR | MTL | RL |
|
|
* ----------------------------------------------------------
|
|
* 0 4 41 42 43 44 48 54 56 60
|
|
*
|
|
* PSSCR key fields:
|
|
* Bits 0:3 - Power-Saving Level Status (PLS). This field indicates the
|
|
* lowest power-saving state the thread entered since stop instruction was
|
|
* last executed.
|
|
*
|
|
* Bit 41 - Status Disable(SD)
|
|
* 0 - Shows PLS entries
|
|
* 1 - PLS entries are all 0
|
|
*
|
|
* Bit 42 - Enable State Loss
|
|
* 0 - No state is lost irrespective of other fields
|
|
* 1 - Allows state loss
|
|
*
|
|
* Bit 43 - Exit Criterion
|
|
* 0 - Exit from power-save mode on any interrupt
|
|
* 1 - Exit from power-save mode controlled by LPCR's PECE bits
|
|
*
|
|
* Bits 44:47 - Power-Saving Level Limit
|
|
* This limits the power-saving level that can be entered into.
|
|
*
|
|
* Bits 60:63 - Requested Level
|
|
* Used to specify which power-saving level must be entered on executing
|
|
* stop instruction
|
|
*/
|
|
|
|
int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags)
|
|
{
|
|
int err = 0;
|
|
|
|
/*
|
|
* psscr_mask == 0xf indicates an older firmware.
|
|
* Set remaining fields of psscr to the default values.
|
|
* See NOTE above definition of PSSCR_HV_DEFAULT_VAL
|
|
*/
|
|
if (*psscr_mask == 0xf) {
|
|
*psscr_val = *psscr_val | PSSCR_HV_DEFAULT_VAL;
|
|
*psscr_mask = PSSCR_HV_DEFAULT_MASK;
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* New firmware is expected to set the psscr_val bits correctly.
|
|
* Validate that the following invariants are correctly maintained by
|
|
* the new firmware.
|
|
* - ESL bit value matches the EC bit value.
|
|
* - ESL bit is set for all the deep stop states.
|
|
*/
|
|
if (GET_PSSCR_ESL(*psscr_val) != GET_PSSCR_EC(*psscr_val)) {
|
|
err = ERR_EC_ESL_MISMATCH;
|
|
} else if ((flags & OPAL_PM_LOSE_FULL_CONTEXT) &&
|
|
GET_PSSCR_ESL(*psscr_val) == 0) {
|
|
err = ERR_DEEP_STATE_ESL_MISMATCH;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* pnv_arch300_idle_init: Initializes the default idle state, first
|
|
* deep idle state and deepest idle state on
|
|
* ISA 3.0 CPUs.
|
|
*
|
|
* @np: /ibm,opal/power-mgt device node
|
|
* @flags: cpu-idle-state-flags array
|
|
* @dt_idle_states: Number of idle state entries
|
|
* Returns 0 on success
|
|
*/
|
|
static void __init pnv_power9_idle_init(void)
|
|
{
|
|
u64 max_residency_ns = 0;
|
|
int i;
|
|
|
|
/*
|
|
* pnv_deepest_stop_{val,mask} should be set to values corresponding to
|
|
* the deepest stop state.
|
|
*
|
|
* pnv_default_stop_{val,mask} should be set to values corresponding to
|
|
* the deepest loss-less (OPAL_PM_STOP_INST_FAST) stop state.
|
|
*/
|
|
pnv_first_tb_loss_level = MAX_STOP_STATE + 1;
|
|
pnv_first_spr_loss_level = MAX_STOP_STATE + 1;
|
|
for (i = 0; i < nr_pnv_idle_states; i++) {
|
|
int err;
|
|
struct pnv_idle_states_t *state = &pnv_idle_states[i];
|
|
u64 psscr_rl = state->psscr_val & PSSCR_RL_MASK;
|
|
|
|
if ((state->flags & OPAL_PM_TIMEBASE_STOP) &&
|
|
(pnv_first_tb_loss_level > psscr_rl))
|
|
pnv_first_tb_loss_level = psscr_rl;
|
|
|
|
if ((state->flags & OPAL_PM_LOSE_FULL_CONTEXT) &&
|
|
(pnv_first_spr_loss_level > psscr_rl))
|
|
pnv_first_spr_loss_level = psscr_rl;
|
|
|
|
/*
|
|
* The idle code does not deal with TB loss occurring
|
|
* in a shallower state than SPR loss, so force it to
|
|
* behave like SPRs are lost if TB is lost. POWER9 would
|
|
* never encouter this, but a POWER8 core would if it
|
|
* implemented the stop instruction. So this is for forward
|
|
* compatibility.
|
|
*/
|
|
if ((state->flags & OPAL_PM_TIMEBASE_STOP) &&
|
|
(pnv_first_spr_loss_level > psscr_rl))
|
|
pnv_first_spr_loss_level = psscr_rl;
|
|
|
|
err = validate_psscr_val_mask(&state->psscr_val,
|
|
&state->psscr_mask,
|
|
state->flags);
|
|
if (err) {
|
|
report_invalid_psscr_val(state->psscr_val, err);
|
|
continue;
|
|
}
|
|
|
|
state->valid = true;
|
|
|
|
if (max_residency_ns < state->residency_ns) {
|
|
max_residency_ns = state->residency_ns;
|
|
pnv_deepest_stop_psscr_val = state->psscr_val;
|
|
pnv_deepest_stop_psscr_mask = state->psscr_mask;
|
|
pnv_deepest_stop_flag = state->flags;
|
|
deepest_stop_found = true;
|
|
}
|
|
|
|
if (!default_stop_found &&
|
|
(state->flags & OPAL_PM_STOP_INST_FAST)) {
|
|
pnv_default_stop_val = state->psscr_val;
|
|
pnv_default_stop_mask = state->psscr_mask;
|
|
default_stop_found = true;
|
|
WARN_ON(state->flags & OPAL_PM_LOSE_FULL_CONTEXT);
|
|
}
|
|
}
|
|
|
|
if (unlikely(!default_stop_found)) {
|
|
pr_warn("cpuidle-powernv: No suitable default stop state found. Disabling platform idle.\n");
|
|
} else {
|
|
ppc_md.power_save = power9_idle;
|
|
pr_info("cpuidle-powernv: Default stop: psscr = 0x%016llx,mask=0x%016llx\n",
|
|
pnv_default_stop_val, pnv_default_stop_mask);
|
|
}
|
|
|
|
if (unlikely(!deepest_stop_found)) {
|
|
pr_warn("cpuidle-powernv: No suitable stop state for CPU-Hotplug. Offlined CPUs will busy wait");
|
|
} else {
|
|
pr_info("cpuidle-powernv: Deepest stop: psscr = 0x%016llx,mask=0x%016llx\n",
|
|
pnv_deepest_stop_psscr_val,
|
|
pnv_deepest_stop_psscr_mask);
|
|
}
|
|
|
|
pr_info("cpuidle-powernv: First stop level that may lose SPRs = 0x%lld\n",
|
|
pnv_first_spr_loss_level);
|
|
|
|
pr_info("cpuidle-powernv: First stop level that may lose timebase = 0x%lld\n",
|
|
pnv_first_tb_loss_level);
|
|
}
|
|
|
|
static void __init pnv_disable_deep_states(void)
|
|
{
|
|
/*
|
|
* The stop-api is unable to restore hypervisor
|
|
* resources on wakeup from platform idle states which
|
|
* lose full context. So disable such states.
|
|
*/
|
|
supported_cpuidle_states &= ~OPAL_PM_LOSE_FULL_CONTEXT;
|
|
pr_warn("cpuidle-powernv: Disabling idle states that lose full context\n");
|
|
pr_warn("cpuidle-powernv: Idle power-savings, CPU-Hotplug affected\n");
|
|
|
|
if (cpu_has_feature(CPU_FTR_ARCH_300) &&
|
|
(pnv_deepest_stop_flag & OPAL_PM_LOSE_FULL_CONTEXT)) {
|
|
/*
|
|
* Use the default stop state for CPU-Hotplug
|
|
* if available.
|
|
*/
|
|
if (default_stop_found) {
|
|
pnv_deepest_stop_psscr_val = pnv_default_stop_val;
|
|
pnv_deepest_stop_psscr_mask = pnv_default_stop_mask;
|
|
pr_warn("cpuidle-powernv: Offlined CPUs will stop with psscr = 0x%016llx\n",
|
|
pnv_deepest_stop_psscr_val);
|
|
} else { /* Fallback to snooze loop for CPU-Hotplug */
|
|
deepest_stop_found = false;
|
|
pr_warn("cpuidle-powernv: Offlined CPUs will busy wait\n");
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Probe device tree for supported idle states
|
|
*/
|
|
static void __init pnv_probe_idle_states(void)
|
|
{
|
|
int i;
|
|
|
|
if (nr_pnv_idle_states < 0) {
|
|
pr_warn("cpuidle-powernv: no idle states found in the DT\n");
|
|
return;
|
|
}
|
|
|
|
if (cpu_has_feature(CPU_FTR_ARCH_300))
|
|
pnv_power9_idle_init();
|
|
|
|
for (i = 0; i < nr_pnv_idle_states; i++)
|
|
supported_cpuidle_states |= pnv_idle_states[i].flags;
|
|
}
|
|
|
|
/*
|
|
* This function parses device-tree and populates all the information
|
|
* into pnv_idle_states structure. It also sets up nr_pnv_idle_states
|
|
* which is the number of cpuidle states discovered through device-tree.
|
|
*/
|
|
|
|
static int pnv_parse_cpuidle_dt(void)
|
|
{
|
|
struct device_node *np;
|
|
int nr_idle_states, i;
|
|
int rc = 0;
|
|
u32 *temp_u32;
|
|
u64 *temp_u64;
|
|
const char **temp_string;
|
|
|
|
np = of_find_node_by_path("/ibm,opal/power-mgt");
|
|
if (!np) {
|
|
pr_warn("opal: PowerMgmt Node not found\n");
|
|
return -ENODEV;
|
|
}
|
|
nr_idle_states = of_property_count_u32_elems(np,
|
|
"ibm,cpu-idle-state-flags");
|
|
|
|
pnv_idle_states = kcalloc(nr_idle_states, sizeof(*pnv_idle_states),
|
|
GFP_KERNEL);
|
|
temp_u32 = kcalloc(nr_idle_states, sizeof(u32), GFP_KERNEL);
|
|
temp_u64 = kcalloc(nr_idle_states, sizeof(u64), GFP_KERNEL);
|
|
temp_string = kcalloc(nr_idle_states, sizeof(char *), GFP_KERNEL);
|
|
|
|
if (!(pnv_idle_states && temp_u32 && temp_u64 && temp_string)) {
|
|
pr_err("Could not allocate memory for dt parsing\n");
|
|
rc = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
/* Read flags */
|
|
if (of_property_read_u32_array(np, "ibm,cpu-idle-state-flags",
|
|
temp_u32, nr_idle_states)) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-flags in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
pnv_idle_states[i].flags = temp_u32[i];
|
|
|
|
/* Read latencies */
|
|
if (of_property_read_u32_array(np, "ibm,cpu-idle-state-latencies-ns",
|
|
temp_u32, nr_idle_states)) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
pnv_idle_states[i].latency_ns = temp_u32[i];
|
|
|
|
/* Read residencies */
|
|
if (of_property_read_u32_array(np, "ibm,cpu-idle-state-residency-ns",
|
|
temp_u32, nr_idle_states)) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-latencies-ns in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
pnv_idle_states[i].residency_ns = temp_u32[i];
|
|
|
|
/* For power9 */
|
|
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
|
|
/* Read pm_crtl_val */
|
|
if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr",
|
|
temp_u64, nr_idle_states)) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
pnv_idle_states[i].psscr_val = temp_u64[i];
|
|
|
|
/* Read pm_crtl_mask */
|
|
if (of_property_read_u64_array(np, "ibm,cpu-idle-state-psscr-mask",
|
|
temp_u64, nr_idle_states)) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr-mask in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
pnv_idle_states[i].psscr_mask = temp_u64[i];
|
|
}
|
|
|
|
/*
|
|
* power8 specific properties ibm,cpu-idle-state-pmicr-mask and
|
|
* ibm,cpu-idle-state-pmicr-val were never used and there is no
|
|
* plan to use it in near future. Hence, not parsing these properties
|
|
*/
|
|
|
|
if (of_property_read_string_array(np, "ibm,cpu-idle-state-names",
|
|
temp_string, nr_idle_states) < 0) {
|
|
pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-names in DT\n");
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < nr_idle_states; i++)
|
|
strlcpy(pnv_idle_states[i].name, temp_string[i],
|
|
PNV_IDLE_NAME_LEN);
|
|
nr_pnv_idle_states = nr_idle_states;
|
|
rc = 0;
|
|
out:
|
|
kfree(temp_u32);
|
|
kfree(temp_u64);
|
|
kfree(temp_string);
|
|
return rc;
|
|
}
|
|
|
|
static int __init pnv_init_idle_states(void)
|
|
{
|
|
int cpu;
|
|
int rc = 0;
|
|
|
|
/* Set up PACA fields */
|
|
for_each_present_cpu(cpu) {
|
|
struct paca_struct *p = paca_ptrs[cpu];
|
|
|
|
p->idle_state = 0;
|
|
if (cpu == cpu_first_thread_sibling(cpu))
|
|
p->idle_state = (1 << threads_per_core) - 1;
|
|
|
|
if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
|
|
/* P7/P8 nap */
|
|
p->thread_idle_state = PNV_THREAD_RUNNING;
|
|
} else {
|
|
/* P9 stop */
|
|
#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
|
|
p->requested_psscr = 0;
|
|
atomic_set(&p->dont_stop, 0);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/* In case we error out nr_pnv_idle_states will be zero */
|
|
nr_pnv_idle_states = 0;
|
|
supported_cpuidle_states = 0;
|
|
|
|
if (cpuidle_disable != IDLE_NO_OVERRIDE)
|
|
goto out;
|
|
rc = pnv_parse_cpuidle_dt();
|
|
if (rc)
|
|
return rc;
|
|
pnv_probe_idle_states();
|
|
|
|
if (!cpu_has_feature(CPU_FTR_ARCH_300)) {
|
|
if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
|
|
power7_fastsleep_workaround_entry = false;
|
|
power7_fastsleep_workaround_exit = false;
|
|
} else {
|
|
/*
|
|
* OPAL_PM_SLEEP_ENABLED_ER1 is set. It indicates that
|
|
* workaround is needed to use fastsleep. Provide sysfs
|
|
* control to choose how this workaround has to be
|
|
* applied.
|
|
*/
|
|
device_create_file(cpu_subsys.dev_root,
|
|
&dev_attr_fastsleep_workaround_applyonce);
|
|
}
|
|
|
|
update_subcore_sibling_mask();
|
|
|
|
if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED) {
|
|
ppc_md.power_save = power7_idle;
|
|
power7_offline_type = PNV_THREAD_NAP;
|
|
}
|
|
|
|
if ((supported_cpuidle_states & OPAL_PM_WINKLE_ENABLED) &&
|
|
(supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT))
|
|
power7_offline_type = PNV_THREAD_WINKLE;
|
|
else if ((supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED) ||
|
|
(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1))
|
|
power7_offline_type = PNV_THREAD_SLEEP;
|
|
}
|
|
|
|
if (supported_cpuidle_states & OPAL_PM_LOSE_FULL_CONTEXT) {
|
|
if (pnv_save_sprs_for_deep_states())
|
|
pnv_disable_deep_states();
|
|
}
|
|
|
|
out:
|
|
return 0;
|
|
}
|
|
machine_subsys_initcall(powernv, pnv_init_idle_states);
|