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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/cpufreq/speedstep-lib.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
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/cpufreq/speedstep-lib.c')
-rw-r--r-- | drivers/cpufreq/speedstep-lib.c | 479 |
1 files changed, 479 insertions, 0 deletions
diff --git a/drivers/cpufreq/speedstep-lib.c b/drivers/cpufreq/speedstep-lib.c new file mode 100644 index 000000000..0b66df4ed --- /dev/null +++ b/drivers/cpufreq/speedstep-lib.c @@ -0,0 +1,479 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> + * + * Library for common functions for Intel SpeedStep v.1 and v.2 support + * + * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous* + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/cpufreq.h> + +#include <asm/msr.h> +#include <asm/tsc.h> +#include "speedstep-lib.h" + +#define PFX "speedstep-lib: " + +#ifdef CONFIG_X86_SPEEDSTEP_RELAXED_CAP_CHECK +static int relaxed_check; +#else +#define relaxed_check 0 +#endif + +/********************************************************************* + * GET PROCESSOR CORE SPEED IN KHZ * + *********************************************************************/ + +static unsigned int pentium3_get_frequency(enum speedstep_processor processor) +{ + /* See table 14 of p3_ds.pdf and table 22 of 29834003.pdf */ + static const struct { + unsigned int ratio; /* Frequency Multiplier (x10) */ + u8 bitmap; /* power on configuration bits + [27, 25:22] (in MSR 0x2a) */ + } msr_decode_mult[] = { + { 30, 0x01 }, + { 35, 0x05 }, + { 40, 0x02 }, + { 45, 0x06 }, + { 50, 0x00 }, + { 55, 0x04 }, + { 60, 0x0b }, + { 65, 0x0f }, + { 70, 0x09 }, + { 75, 0x0d }, + { 80, 0x0a }, + { 85, 0x26 }, + { 90, 0x20 }, + { 100, 0x2b }, + { 0, 0xff } /* error or unknown value */ + }; + + /* PIII(-M) FSB settings: see table b1-b of 24547206.pdf */ + static const struct { + unsigned int value; /* Front Side Bus speed in MHz */ + u8 bitmap; /* power on configuration bits [18: 19] + (in MSR 0x2a) */ + } msr_decode_fsb[] = { + { 66, 0x0 }, + { 100, 0x2 }, + { 133, 0x1 }, + { 0, 0xff} + }; + + u32 msr_lo, msr_tmp; + int i = 0, j = 0; + + /* read MSR 0x2a - we only need the low 32 bits */ + rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp); + pr_debug("P3 - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp); + msr_tmp = msr_lo; + + /* decode the FSB */ + msr_tmp &= 0x00c0000; + msr_tmp >>= 18; + while (msr_tmp != msr_decode_fsb[i].bitmap) { + if (msr_decode_fsb[i].bitmap == 0xff) + return 0; + i++; + } + + /* decode the multiplier */ + if (processor == SPEEDSTEP_CPU_PIII_C_EARLY) { + pr_debug("workaround for early PIIIs\n"); + msr_lo &= 0x03c00000; + } else + msr_lo &= 0x0bc00000; + msr_lo >>= 22; + while (msr_lo != msr_decode_mult[j].bitmap) { + if (msr_decode_mult[j].bitmap == 0xff) + return 0; + j++; + } + + pr_debug("speed is %u\n", + (msr_decode_mult[j].ratio * msr_decode_fsb[i].value * 100)); + + return msr_decode_mult[j].ratio * msr_decode_fsb[i].value * 100; +} + + +static unsigned int pentiumM_get_frequency(void) +{ + u32 msr_lo, msr_tmp; + + rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp); + pr_debug("PM - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", msr_lo, msr_tmp); + + /* see table B-2 of 24547212.pdf */ + if (msr_lo & 0x00040000) { + printk(KERN_DEBUG PFX "PM - invalid FSB: 0x%x 0x%x\n", + msr_lo, msr_tmp); + return 0; + } + + msr_tmp = (msr_lo >> 22) & 0x1f; + pr_debug("bits 22-26 are 0x%x, speed is %u\n", + msr_tmp, (msr_tmp * 100 * 1000)); + + return msr_tmp * 100 * 1000; +} + +static unsigned int pentium_core_get_frequency(void) +{ + u32 fsb = 0; + u32 msr_lo, msr_tmp; + int ret; + + rdmsr(MSR_FSB_FREQ, msr_lo, msr_tmp); + /* see table B-2 of 25366920.pdf */ + switch (msr_lo & 0x07) { + case 5: + fsb = 100000; + break; + case 1: + fsb = 133333; + break; + case 3: + fsb = 166667; + break; + case 2: + fsb = 200000; + break; + case 0: + fsb = 266667; + break; + case 4: + fsb = 333333; + break; + default: + pr_err("PCORE - MSR_FSB_FREQ undefined value\n"); + } + + rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_tmp); + pr_debug("PCORE - MSR_IA32_EBL_CR_POWERON: 0x%x 0x%x\n", + msr_lo, msr_tmp); + + msr_tmp = (msr_lo >> 22) & 0x1f; + pr_debug("bits 22-26 are 0x%x, speed is %u\n", + msr_tmp, (msr_tmp * fsb)); + + ret = (msr_tmp * fsb); + return ret; +} + + +static unsigned int pentium4_get_frequency(void) +{ + struct cpuinfo_x86 *c = &boot_cpu_data; + u32 msr_lo, msr_hi, mult; + unsigned int fsb = 0; + unsigned int ret; + u8 fsb_code; + + /* Pentium 4 Model 0 and 1 do not have the Core Clock Frequency + * to System Bus Frequency Ratio Field in the Processor Frequency + * Configuration Register of the MSR. Therefore the current + * frequency cannot be calculated and has to be measured. + */ + if (c->x86_model < 2) + return cpu_khz; + + rdmsr(0x2c, msr_lo, msr_hi); + + pr_debug("P4 - MSR_EBC_FREQUENCY_ID: 0x%x 0x%x\n", msr_lo, msr_hi); + + /* decode the FSB: see IA-32 Intel (C) Architecture Software + * Developer's Manual, Volume 3: System Prgramming Guide, + * revision #12 in Table B-1: MSRs in the Pentium 4 and + * Intel Xeon Processors, on page B-4 and B-5. + */ + fsb_code = (msr_lo >> 16) & 0x7; + switch (fsb_code) { + case 0: + fsb = 100 * 1000; + break; + case 1: + fsb = 13333 * 10; + break; + case 2: + fsb = 200 * 1000; + break; + } + + if (!fsb) + printk(KERN_DEBUG PFX "couldn't detect FSB speed. " + "Please send an e-mail to <linux@brodo.de>\n"); + + /* Multiplier. */ + mult = msr_lo >> 24; + + pr_debug("P4 - FSB %u kHz; Multiplier %u; Speed %u kHz\n", + fsb, mult, (fsb * mult)); + + ret = (fsb * mult); + return ret; +} + + +/* Warning: may get called from smp_call_function_single. */ +unsigned int speedstep_get_frequency(enum speedstep_processor processor) +{ + switch (processor) { + case SPEEDSTEP_CPU_PCORE: + return pentium_core_get_frequency(); + case SPEEDSTEP_CPU_PM: + return pentiumM_get_frequency(); + case SPEEDSTEP_CPU_P4D: + case SPEEDSTEP_CPU_P4M: + return pentium4_get_frequency(); + case SPEEDSTEP_CPU_PIII_T: + case SPEEDSTEP_CPU_PIII_C: + case SPEEDSTEP_CPU_PIII_C_EARLY: + return pentium3_get_frequency(processor); + default: + return 0; + } + return 0; +} +EXPORT_SYMBOL_GPL(speedstep_get_frequency); + + +/********************************************************************* + * DETECT SPEEDSTEP-CAPABLE PROCESSOR * + *********************************************************************/ + +/* Keep in sync with the x86_cpu_id tables in the different modules */ +enum speedstep_processor speedstep_detect_processor(void) +{ + struct cpuinfo_x86 *c = &cpu_data(0); + u32 ebx, msr_lo, msr_hi; + + pr_debug("x86: %x, model: %x\n", c->x86, c->x86_model); + + if ((c->x86_vendor != X86_VENDOR_INTEL) || + ((c->x86 != 6) && (c->x86 != 0xF))) + return 0; + + if (c->x86 == 0xF) { + /* Intel Mobile Pentium 4-M + * or Intel Mobile Pentium 4 with 533 MHz FSB */ + if (c->x86_model != 2) + return 0; + + ebx = cpuid_ebx(0x00000001); + ebx &= 0x000000FF; + + pr_debug("ebx value is %x, x86_stepping is %x\n", ebx, c->x86_stepping); + + switch (c->x86_stepping) { + case 4: + /* + * B-stepping [M-P4-M] + * sample has ebx = 0x0f, production has 0x0e. + */ + if ((ebx == 0x0e) || (ebx == 0x0f)) + return SPEEDSTEP_CPU_P4M; + break; + case 7: + /* + * C-stepping [M-P4-M] + * needs to have ebx=0x0e, else it's a celeron: + * cf. 25130917.pdf / page 7, footnote 5 even + * though 25072120.pdf / page 7 doesn't say + * samples are only of B-stepping... + */ + if (ebx == 0x0e) + return SPEEDSTEP_CPU_P4M; + break; + case 9: + /* + * D-stepping [M-P4-M or M-P4/533] + * + * this is totally strange: CPUID 0x0F29 is + * used by M-P4-M, M-P4/533 and(!) Celeron CPUs. + * The latter need to be sorted out as they don't + * support speedstep. + * Celerons with CPUID 0x0F29 may have either + * ebx=0x8 or 0xf -- 25130917.pdf doesn't say anything + * specific. + * M-P4-Ms may have either ebx=0xe or 0xf [see above] + * M-P4/533 have either ebx=0xe or 0xf. [25317607.pdf] + * also, M-P4M HTs have ebx=0x8, too + * For now, they are distinguished by the model_id + * string + */ + if ((ebx == 0x0e) || + (strstr(c->x86_model_id, + "Mobile Intel(R) Pentium(R) 4") != NULL)) + return SPEEDSTEP_CPU_P4M; + break; + default: + break; + } + return 0; + } + + switch (c->x86_model) { + case 0x0B: /* Intel PIII [Tualatin] */ + /* cpuid_ebx(1) is 0x04 for desktop PIII, + * 0x06 for mobile PIII-M */ + ebx = cpuid_ebx(0x00000001); + pr_debug("ebx is %x\n", ebx); + + ebx &= 0x000000FF; + + if (ebx != 0x06) + return 0; + + /* So far all PIII-M processors support SpeedStep. See + * Intel's 24540640.pdf of June 2003 + */ + return SPEEDSTEP_CPU_PIII_T; + + case 0x08: /* Intel PIII [Coppermine] */ + + /* all mobile PIII Coppermines have FSB 100 MHz + * ==> sort out a few desktop PIIIs. */ + rdmsr(MSR_IA32_EBL_CR_POWERON, msr_lo, msr_hi); + pr_debug("Coppermine: MSR_IA32_EBL_CR_POWERON is 0x%x, 0x%x\n", + msr_lo, msr_hi); + msr_lo &= 0x00c0000; + if (msr_lo != 0x0080000) + return 0; + + /* + * If the processor is a mobile version, + * platform ID has bit 50 set + * it has SpeedStep technology if either + * bit 56 or 57 is set + */ + rdmsr(MSR_IA32_PLATFORM_ID, msr_lo, msr_hi); + pr_debug("Coppermine: MSR_IA32_PLATFORM ID is 0x%x, 0x%x\n", + msr_lo, msr_hi); + if ((msr_hi & (1<<18)) && + (relaxed_check ? 1 : (msr_hi & (3<<24)))) { + if (c->x86_stepping == 0x01) { + pr_debug("early PIII version\n"); + return SPEEDSTEP_CPU_PIII_C_EARLY; + } else + return SPEEDSTEP_CPU_PIII_C; + } + fallthrough; + default: + return 0; + } +} +EXPORT_SYMBOL_GPL(speedstep_detect_processor); + + +/********************************************************************* + * DETECT SPEEDSTEP SPEEDS * + *********************************************************************/ + +unsigned int speedstep_get_freqs(enum speedstep_processor processor, + unsigned int *low_speed, + unsigned int *high_speed, + unsigned int *transition_latency, + void (*set_state) (unsigned int state)) +{ + unsigned int prev_speed; + unsigned int ret = 0; + unsigned long flags; + ktime_t tv1, tv2; + + if ((!processor) || (!low_speed) || (!high_speed) || (!set_state)) + return -EINVAL; + + pr_debug("trying to determine both speeds\n"); + + /* get current speed */ + prev_speed = speedstep_get_frequency(processor); + if (!prev_speed) + return -EIO; + + pr_debug("previous speed is %u\n", prev_speed); + + preempt_disable(); + local_irq_save(flags); + + /* switch to low state */ + set_state(SPEEDSTEP_LOW); + *low_speed = speedstep_get_frequency(processor); + if (!*low_speed) { + ret = -EIO; + goto out; + } + + pr_debug("low speed is %u\n", *low_speed); + + /* start latency measurement */ + if (transition_latency) + tv1 = ktime_get(); + + /* switch to high state */ + set_state(SPEEDSTEP_HIGH); + + /* end latency measurement */ + if (transition_latency) + tv2 = ktime_get(); + + *high_speed = speedstep_get_frequency(processor); + if (!*high_speed) { + ret = -EIO; + goto out; + } + + pr_debug("high speed is %u\n", *high_speed); + + if (*low_speed == *high_speed) { + ret = -ENODEV; + goto out; + } + + /* switch to previous state, if necessary */ + if (*high_speed != prev_speed) + set_state(SPEEDSTEP_LOW); + + if (transition_latency) { + *transition_latency = ktime_to_us(ktime_sub(tv2, tv1)); + pr_debug("transition latency is %u uSec\n", *transition_latency); + + /* convert uSec to nSec and add 20% for safety reasons */ + *transition_latency *= 1200; + + /* check if the latency measurement is too high or too low + * and set it to a safe value (500uSec) in that case + */ + if (*transition_latency > 10000000 || + *transition_latency < 50000) { + pr_warn("frequency transition measured seems out of range (%u nSec), falling back to a safe one of %u nSec\n", + *transition_latency, 500000); + *transition_latency = 500000; + } + } + +out: + local_irq_restore(flags); + preempt_enable(); + + return ret; +} +EXPORT_SYMBOL_GPL(speedstep_get_freqs); + +#ifdef CONFIG_X86_SPEEDSTEP_RELAXED_CAP_CHECK +module_param(relaxed_check, int, 0444); +MODULE_PARM_DESC(relaxed_check, + "Don't do all checks for speedstep capability."); +#endif + +MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>"); +MODULE_DESCRIPTION("Library for Intel SpeedStep 1 or 2 cpufreq drivers."); +MODULE_LICENSE("GPL"); |