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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/cpuidle/cpuidle-pseries.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/cpuidle/cpuidle-pseries.c')
-rw-r--r--drivers/cpuidle/cpuidle-pseries.c483
1 files changed, 483 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
new file mode 100644
index 000000000..1bad4d2b7
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -0,0 +1,483 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * cpuidle-pseries - idle state cpuidle driver.
+ * Adapted from drivers/idle/intel_idle.c and
+ * drivers/acpi/processor_idle.c
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/cpuidle.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+
+#include <asm/paca.h>
+#include <asm/reg.h>
+#include <asm/machdep.h>
+#include <asm/firmware.h>
+#include <asm/runlatch.h>
+#include <asm/idle.h>
+#include <asm/plpar_wrappers.h>
+#include <asm/rtas.h>
+
+static struct cpuidle_driver pseries_idle_driver = {
+ .name = "pseries_idle",
+ .owner = THIS_MODULE,
+};
+
+static int max_idle_state __read_mostly;
+static struct cpuidle_state *cpuidle_state_table __read_mostly;
+static u64 snooze_timeout __read_mostly;
+static bool snooze_timeout_en __read_mostly;
+
+static int snooze_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ u64 snooze_exit_time;
+
+ set_thread_flag(TIF_POLLING_NRFLAG);
+
+ pseries_idle_prolog();
+ local_irq_enable();
+ snooze_exit_time = get_tb() + snooze_timeout;
+ dev->poll_time_limit = false;
+
+ while (!need_resched()) {
+ HMT_low();
+ HMT_very_low();
+ if (likely(snooze_timeout_en) && get_tb() > snooze_exit_time) {
+ /*
+ * Task has not woken up but we are exiting the polling
+ * loop anyway. Require a barrier after polling is
+ * cleared to order subsequent test of need_resched().
+ */
+ dev->poll_time_limit = true;
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+ smp_mb();
+ break;
+ }
+ }
+
+ HMT_medium();
+ clear_thread_flag(TIF_POLLING_NRFLAG);
+
+ local_irq_disable();
+
+ pseries_idle_epilog();
+
+ return index;
+}
+
+static void check_and_cede_processor(void)
+{
+ /*
+ * Ensure our interrupt state is properly tracked,
+ * also checks if no interrupt has occurred while we
+ * were soft-disabled
+ */
+ if (prep_irq_for_idle()) {
+ cede_processor();
+#ifdef CONFIG_TRACE_IRQFLAGS
+ /* Ensure that H_CEDE returns with IRQs on */
+ if (WARN_ON(!(mfmsr() & MSR_EE)))
+ __hard_irq_enable();
+#endif
+ }
+}
+
+/*
+ * XCEDE: Extended CEDE states discovered through the
+ * "ibm,get-systems-parameter" RTAS call with the token
+ * CEDE_LATENCY_TOKEN
+ */
+
+/*
+ * Section 7.3.16 System Parameters Option of PAPR version 2.8.1 has a
+ * table with all the parameters to ibm,get-system-parameters.
+ * CEDE_LATENCY_TOKEN corresponds to the token value for Cede Latency
+ * Settings Information.
+ */
+#define CEDE_LATENCY_TOKEN 45
+
+/*
+ * If the platform supports the cede latency settings information system
+ * parameter it must provide the following information in the NULL terminated
+ * parameter string:
+ *
+ * a. The first byte is the length ā€œNā€ of each cede latency setting record minus
+ * one (zero indicates a length of 1 byte).
+ *
+ * b. For each supported cede latency setting a cede latency setting record
+ * consisting of the first ā€œNā€ bytes as per the following table.
+ *
+ * -----------------------------
+ * | Field | Field |
+ * | Name | Length |
+ * -----------------------------
+ * | Cede Latency | 1 Byte |
+ * | Specifier Value | |
+ * -----------------------------
+ * | Maximum wakeup | |
+ * | latency in | 8 Bytes |
+ * | tb-ticks | |
+ * -----------------------------
+ * | Responsive to | |
+ * | external | 1 Byte |
+ * | interrupts | |
+ * -----------------------------
+ *
+ * This version has cede latency record size = 10.
+ *
+ * The structure xcede_latency_payload represents a) and b) with
+ * xcede_latency_record representing the table in b).
+ *
+ * xcede_latency_parameter is what gets returned by
+ * ibm,get-systems-parameter RTAS call when made with
+ * CEDE_LATENCY_TOKEN.
+ *
+ * These structures are only used to represent the data obtained by the RTAS
+ * call. The data is in big-endian.
+ */
+struct xcede_latency_record {
+ u8 hint;
+ __be64 latency_ticks;
+ u8 wake_on_irqs;
+} __packed;
+
+// Make space for 16 records, which "should be enough".
+struct xcede_latency_payload {
+ u8 record_size;
+ struct xcede_latency_record records[16];
+} __packed;
+
+struct xcede_latency_parameter {
+ __be16 payload_size;
+ struct xcede_latency_payload payload;
+ u8 null_char;
+} __packed;
+
+static unsigned int nr_xcede_records;
+static struct xcede_latency_parameter xcede_latency_parameter __initdata;
+
+static int __init parse_cede_parameters(void)
+{
+ struct xcede_latency_payload *payload;
+ u32 total_xcede_records_size;
+ u8 xcede_record_size;
+ u16 payload_size;
+ int ret, i;
+
+ ret = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1,
+ NULL, CEDE_LATENCY_TOKEN, __pa(&xcede_latency_parameter),
+ sizeof(xcede_latency_parameter));
+ if (ret) {
+ pr_err("xcede: Error parsing CEDE_LATENCY_TOKEN\n");
+ return ret;
+ }
+
+ payload_size = be16_to_cpu(xcede_latency_parameter.payload_size);
+ payload = &xcede_latency_parameter.payload;
+
+ xcede_record_size = payload->record_size + 1;
+
+ if (xcede_record_size != sizeof(struct xcede_latency_record)) {
+ pr_err("xcede: Expected record-size %lu. Observed size %u.\n",
+ sizeof(struct xcede_latency_record), xcede_record_size);
+ return -EINVAL;
+ }
+
+ pr_info("xcede: xcede_record_size = %d\n", xcede_record_size);
+
+ /*
+ * Since the payload_size includes the last NULL byte and the
+ * xcede_record_size, the remaining bytes correspond to array of all
+ * cede_latency settings.
+ */
+ total_xcede_records_size = payload_size - 2;
+ nr_xcede_records = total_xcede_records_size / xcede_record_size;
+
+ for (i = 0; i < nr_xcede_records; i++) {
+ struct xcede_latency_record *record = &payload->records[i];
+ u64 latency_ticks = be64_to_cpu(record->latency_ticks);
+ u8 wake_on_irqs = record->wake_on_irqs;
+ u8 hint = record->hint;
+
+ pr_info("xcede: Record %d : hint = %u, latency = 0x%llx tb ticks, Wake-on-irq = %u\n",
+ i, hint, latency_ticks, wake_on_irqs);
+ }
+
+ return 0;
+}
+
+#define NR_DEDICATED_STATES 2 /* snooze, CEDE */
+static u8 cede_latency_hint[NR_DEDICATED_STATES];
+
+static int dedicated_cede_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+ u8 old_latency_hint;
+
+ pseries_idle_prolog();
+ get_lppaca()->donate_dedicated_cpu = 1;
+ old_latency_hint = get_lppaca()->cede_latency_hint;
+ get_lppaca()->cede_latency_hint = cede_latency_hint[index];
+
+ HMT_medium();
+ check_and_cede_processor();
+
+ local_irq_disable();
+ get_lppaca()->donate_dedicated_cpu = 0;
+ get_lppaca()->cede_latency_hint = old_latency_hint;
+
+ pseries_idle_epilog();
+
+ return index;
+}
+
+static int shared_cede_loop(struct cpuidle_device *dev,
+ struct cpuidle_driver *drv,
+ int index)
+{
+
+ pseries_idle_prolog();
+
+ /*
+ * Yield the processor to the hypervisor. We return if
+ * an external interrupt occurs (which are driven prior
+ * to returning here) or if a prod occurs from another
+ * processor. When returning here, external interrupts
+ * are enabled.
+ */
+ check_and_cede_processor();
+
+ local_irq_disable();
+ pseries_idle_epilog();
+
+ return index;
+}
+
+/*
+ * States for dedicated partition case.
+ */
+static struct cpuidle_state dedicated_states[NR_DEDICATED_STATES] = {
+ { /* Snooze */
+ .name = "snooze",
+ .desc = "snooze",
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &snooze_loop,
+ .flags = CPUIDLE_FLAG_POLLING },
+ { /* CEDE */
+ .name = "CEDE",
+ .desc = "CEDE",
+ .exit_latency = 10,
+ .target_residency = 100,
+ .enter = &dedicated_cede_loop },
+};
+
+/*
+ * States for shared partition case.
+ */
+static struct cpuidle_state shared_states[] = {
+ { /* Snooze */
+ .name = "snooze",
+ .desc = "snooze",
+ .exit_latency = 0,
+ .target_residency = 0,
+ .enter = &snooze_loop,
+ .flags = CPUIDLE_FLAG_POLLING },
+ { /* Shared Cede */
+ .name = "Shared Cede",
+ .desc = "Shared Cede",
+ .exit_latency = 10,
+ .target_residency = 100,
+ .enter = &shared_cede_loop },
+};
+
+static int pseries_cpuidle_cpu_online(unsigned int cpu)
+{
+ struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
+
+ if (dev && cpuidle_get_driver()) {
+ cpuidle_pause_and_lock();
+ cpuidle_enable_device(dev);
+ cpuidle_resume_and_unlock();
+ }
+ return 0;
+}
+
+static int pseries_cpuidle_cpu_dead(unsigned int cpu)
+{
+ struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
+
+ if (dev && cpuidle_get_driver()) {
+ cpuidle_pause_and_lock();
+ cpuidle_disable_device(dev);
+ cpuidle_resume_and_unlock();
+ }
+ return 0;
+}
+
+/*
+ * pseries_cpuidle_driver_init()
+ */
+static int pseries_cpuidle_driver_init(void)
+{
+ int idle_state;
+ struct cpuidle_driver *drv = &pseries_idle_driver;
+
+ drv->state_count = 0;
+
+ for (idle_state = 0; idle_state < max_idle_state; ++idle_state) {
+ /* Is the state not enabled? */
+ if (cpuidle_state_table[idle_state].enter == NULL)
+ continue;
+
+ drv->states[drv->state_count] = /* structure copy */
+ cpuidle_state_table[idle_state];
+
+ drv->state_count += 1;
+ }
+
+ return 0;
+}
+
+static void __init fixup_cede0_latency(void)
+{
+ struct xcede_latency_payload *payload;
+ u64 min_xcede_latency_us = UINT_MAX;
+ int i;
+
+ if (parse_cede_parameters())
+ return;
+
+ pr_info("cpuidle: Skipping the %d Extended CEDE idle states\n",
+ nr_xcede_records);
+
+ payload = &xcede_latency_parameter.payload;
+
+ /*
+ * The CEDE idle state maps to CEDE(0). While the hypervisor
+ * does not advertise CEDE(0) exit latency values, it does
+ * advertise the latency values of the extended CEDE states.
+ * We use the lowest advertised exit latency value as a proxy
+ * for the exit latency of CEDE(0).
+ */
+ for (i = 0; i < nr_xcede_records; i++) {
+ struct xcede_latency_record *record = &payload->records[i];
+ u8 hint = record->hint;
+ u64 latency_tb = be64_to_cpu(record->latency_ticks);
+ u64 latency_us = DIV_ROUND_UP_ULL(tb_to_ns(latency_tb), NSEC_PER_USEC);
+
+ /*
+ * We expect the exit latency of an extended CEDE
+ * state to be non-zero, it to since it takes at least
+ * a few nanoseconds to wakeup the idle CPU and
+ * dispatch the virtual processor into the Linux
+ * Guest.
+ *
+ * So we consider only non-zero value for performing
+ * the fixup of CEDE(0) latency.
+ */
+ if (latency_us == 0) {
+ pr_warn("cpuidle: Skipping xcede record %d [hint=%d]. Exit latency = 0us\n",
+ i, hint);
+ continue;
+ }
+
+ if (latency_us < min_xcede_latency_us)
+ min_xcede_latency_us = latency_us;
+ }
+
+ if (min_xcede_latency_us != UINT_MAX) {
+ dedicated_states[1].exit_latency = min_xcede_latency_us;
+ dedicated_states[1].target_residency = 10 * (min_xcede_latency_us);
+ pr_info("cpuidle: Fixed up CEDE exit latency to %llu us\n",
+ min_xcede_latency_us);
+ }
+
+}
+
+/*
+ * pseries_idle_probe()
+ * Choose state table for shared versus dedicated partition
+ */
+static int __init pseries_idle_probe(void)
+{
+
+ if (cpuidle_disable != IDLE_NO_OVERRIDE)
+ return -ENODEV;
+
+ if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+ /*
+ * Use local_paca instead of get_lppaca() since
+ * preemption is not disabled, and it is not required in
+ * fact, since lppaca_ptr does not need to be the value
+ * associated to the current CPU, it can be from any CPU.
+ */
+ if (lppaca_shared_proc(local_paca->lppaca_ptr)) {
+ cpuidle_state_table = shared_states;
+ max_idle_state = ARRAY_SIZE(shared_states);
+ } else {
+ /*
+ * Use firmware provided latency values
+ * starting with POWER10 platforms. In the
+ * case that we are running on a POWER10
+ * platform but in an earlier compat mode, we
+ * can still use the firmware provided values.
+ *
+ * However, on platforms prior to POWER10, we
+ * cannot rely on the accuracy of the firmware
+ * provided latency values. On such platforms,
+ * go with the conservative default estimate
+ * of 10us.
+ */
+ if (cpu_has_feature(CPU_FTR_ARCH_31) || pvr_version_is(PVR_POWER10))
+ fixup_cede0_latency();
+ cpuidle_state_table = dedicated_states;
+ max_idle_state = NR_DEDICATED_STATES;
+ }
+ } else
+ return -ENODEV;
+
+ if (max_idle_state > 1) {
+ snooze_timeout_en = true;
+ snooze_timeout = cpuidle_state_table[1].target_residency *
+ tb_ticks_per_usec;
+ }
+ return 0;
+}
+
+static int __init pseries_processor_idle_init(void)
+{
+ int retval;
+
+ retval = pseries_idle_probe();
+ if (retval)
+ return retval;
+
+ pseries_cpuidle_driver_init();
+ retval = cpuidle_register(&pseries_idle_driver, NULL);
+ if (retval) {
+ printk(KERN_DEBUG "Registration of pseries driver failed.\n");
+ return retval;
+ }
+
+ retval = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+ "cpuidle/pseries:online",
+ pseries_cpuidle_cpu_online, NULL);
+ WARN_ON(retval < 0);
+ retval = cpuhp_setup_state_nocalls(CPUHP_CPUIDLE_DEAD,
+ "cpuidle/pseries:DEAD", NULL,
+ pseries_cpuidle_cpu_dead);
+ WARN_ON(retval < 0);
+ printk(KERN_DEBUG "pseries_idle_driver registered\n");
+ return 0;
+}
+
+device_initcall(pseries_processor_idle_init);