From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
Mathias Nyman <mathias.nyman@linux.intel.com>,
stable@kernel.org
Subject: [PATCH 5.4 080/108] usb: hub: Fix link power management max exit latency (MEL) calculations
Date: Mon, 26 Jul 2021 17:39:21 +0200 [thread overview]
Message-ID: <20210726153834.241087667@linuxfoundation.org> (raw)
In-Reply-To: <20210726153831.696295003@linuxfoundation.org>
From: Mathias Nyman <mathias.nyman@linux.intel.com>
commit 1bf2761c837571a66ec290fb66c90413821ffda2 upstream.
Maximum Exit Latency (MEL) value is used by host to know how much in
advance it needs to start waking up a U1/U2 suspended link in order to
service a periodic transfer in time.
Current MEL calculation only includes the time to wake up the path from
U1/U2 to U0. This is called tMEL1 in USB 3.1 section C 1.5.2
Total MEL = tMEL1 + tMEL2 +tMEL3 + tMEL4 which should additinally include:
- tMEL2 which is the time it takes for PING message to reach device
- tMEL3 time for device to process the PING and submit a PING_RESPONSE
- tMEL4 time for PING_RESPONSE to traverse back upstream to host.
Add the missing tMEL2, tMEL3 and tMEL4 to MEL calculation.
Cc: <stable@kernel.org> # v3.5
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210715150122.1995966-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/core/hub.c | 52 ++++++++++++++++++++++++++-----------------------
1 file changed, 28 insertions(+), 24 deletions(-)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -46,6 +46,7 @@
#define USB_TP_TRANSMISSION_DELAY 40 /* ns */
#define USB_TP_TRANSMISSION_DELAY_MAX 65535 /* ns */
+#define USB_PING_RESPONSE_TIME 400 /* ns */
/* Protect struct usb_device->state and ->children members
* Note: Both are also protected by ->dev.sem, except that ->state can
@@ -180,8 +181,9 @@ int usb_device_supports_lpm(struct usb_d
}
/*
- * Set the Maximum Exit Latency (MEL) for the host to initiate a transition from
- * either U1 or U2.
+ * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
+ * U1/U2, send a PING to the device and receive a PING_RESPONSE.
+ * See USB 3.1 section C.1.5.2
*/
static void usb_set_lpm_mel(struct usb_device *udev,
struct usb3_lpm_parameters *udev_lpm_params,
@@ -191,35 +193,37 @@ static void usb_set_lpm_mel(struct usb_d
unsigned int hub_exit_latency)
{
unsigned int total_mel;
- unsigned int device_mel;
- unsigned int hub_mel;
/*
- * Calculate the time it takes to transition all links from the roothub
- * to the parent hub into U0. The parent hub must then decode the
- * packet (hub header decode latency) to figure out which port it was
- * bound for.
- *
- * The Hub Header decode latency is expressed in 0.1us intervals (0x1
- * means 0.1us). Multiply that by 100 to get nanoseconds.
+ * tMEL1. time to transition path from host to device into U0.
+ * MEL for parent already contains the delay up to parent, so only add
+ * the exit latency for the last link (pick the slower exit latency),
+ * and the hub header decode latency. See USB 3.1 section C 2.2.1
+ * Store MEL in nanoseconds
*/
total_mel = hub_lpm_params->mel +
- (hub->descriptor->u.ss.bHubHdrDecLat * 100);
+ max(udev_exit_latency, hub_exit_latency) * 1000 +
+ hub->descriptor->u.ss.bHubHdrDecLat * 100;
/*
- * How long will it take to transition the downstream hub's port into
- * U0? The greater of either the hub exit latency or the device exit
- * latency.
- *
- * The BOS U1/U2 exit latencies are expressed in 1us intervals.
- * Multiply that by 1000 to get nanoseconds.
+ * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
+ * each link + wHubDelay for each hub. Add only for last link.
+ * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
+ * Multiply by 2 to include it as well.
*/
- device_mel = udev_exit_latency * 1000;
- hub_mel = hub_exit_latency * 1000;
- if (device_mel > hub_mel)
- total_mel += device_mel;
- else
- total_mel += hub_mel;
+ total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
+ USB_TP_TRANSMISSION_DELAY) * 2;
+
+ /*
+ * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
+ * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
+ * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
+ * Size DP.
+ * Note these delays should be added only once for the entire path, so
+ * add them to the MEL of the device connected to the roothub.
+ */
+ if (!hub->hdev->parent)
+ total_mel += USB_PING_RESPONSE_TIME + 2100;
udev_lpm_params->mel = total_mel;
}
next prev parent reply other threads:[~2021-07-26 15:59 UTC|newest]
Thread overview: 115+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-26 15:38 [PATCH 5.4 000/108] 5.4.136-rc1 review Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 001/108] igc: Fix use-after-free error during reset Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 002/108] igb: " Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 003/108] igc: change default return of igc_read_phy_reg() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 004/108] ixgbe: Fix an error handling path in ixgbe_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 005/108] igc: Prefer to use the pci_release_mem_regions method Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 006/108] igc: Fix an error handling path in igc_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 007/108] igb: Fix an error handling path in igb_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 008/108] fm10k: Fix an error handling path in fm10k_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 009/108] e1000e: Fix an error handling path in e1000_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 010/108] iavf: Fix an error handling path in iavf_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 011/108] igb: Check if num of q_vectors is smaller than max before array access Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 012/108] igb: Fix position of assignment to *ring Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 013/108] gve: Fix an error handling path in gve_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 014/108] ipv6: fix disable_policy for fwd packets Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 015/108] selftests: icmp_redirect: remove from checking for IPv6 route get Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 016/108] selftests: icmp_redirect: IPv6 PMTU info should be cleared after redirect Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 017/108] pwm: sprd: Ensure configuring period and duty_cycle isnt wrongly skipped Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 018/108] cxgb4: fix IRQ free race during driver unload Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 019/108] nvme-pci: do not call nvme_dev_remove_admin from nvme_remove Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 020/108] perf map: Fix dso->nsinfo refcounting Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 021/108] perf probe: " Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 022/108] perf env: Fix sibling_dies memory leak Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 023/108] perf test session_topology: Delete session->evlist Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 024/108] perf test event_update: Fix memory leak of evlist Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 025/108] perf dso: Fix memory leak in dso__new_map() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 026/108] perf script: Fix memory threads and cpus leaks on exit Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 027/108] perf lzma: Close lzma stream " Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 028/108] perf probe-file: Delete namelist in del_events() on the error path Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 029/108] perf data: Close all files in close_dir() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 030/108] spi: imx: add a check for speed_hz before calculating the clock Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 031/108] spi: stm32: Use dma_request_chan() instead dma_request_slave_channel() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 032/108] spi: stm32: fixes pm_runtime calls in probe/remove Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 033/108] regulator: hi6421: Use correct variable type for regmap api val argument Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 034/108] regulator: hi6421: Fix getting wrong drvdata Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 035/108] spi: mediatek: fix fifo rx mode Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 036/108] ASoC: rt5631: Fix regcache sync errors on resume Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 037/108] liquidio: Fix unintentional sign extension issue on left shift of u16 Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 038/108] s390/bpf: Perform r1 range checking before accessing jit->seen_reg[r1] Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 039/108] bpf, sockmap, tcp: sk_prot needs inuse_idx set for proc stats Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 040/108] bpftool: Check malloc return value in mount_bpffs_for_pin Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 041/108] net: fix uninit-value in caif_seqpkt_sendmsg Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 042/108] efi/tpm: Differentiate missing and invalid final event log table Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 043/108] net: decnet: Fix sleeping inside in af_decnet Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 044/108] KVM: PPC: Book3S: Fix CONFIG_TRANSACTIONAL_MEM=n crash Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 045/108] KVM: PPC: Fix kvm_arch_vcpu_ioctl vcpu_load leak Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 046/108] net: sched: fix memory leak in tcindex_partial_destroy_work Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 047/108] netrom: Decrease sock refcount when sock timers expire Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 048/108] scsi: iscsi: Fix iface sysfs attr detection Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 049/108] scsi: target: Fix protect handling in WRITE SAME(32) Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 050/108] spi: cadence: Correct initialisation of runtime PM again Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 051/108] bnxt_en: Improve bnxt_ulp_stop()/bnxt_ulp_start() call sequence Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 052/108] bnxt_en: Refresh RoCE capabilities in bnxt_ulp_probe() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 053/108] bnxt_en: Add missing check for BNXT_STATE_ABORT_ERR in bnxt_fw_rset_task() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 054/108] bnxt_en: Check abort error state in bnxt_half_open_nic() Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 055/108] net: hisilicon: rename CACHE_LINE_MASK to avoid redefinition Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 056/108] net/tcp_fastopen: fix data races around tfo_active_disable_stamp Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 057/108] net: hns3: fix rx VLAN offload state inconsistent issue Greg Kroah-Hartman
2021-07-26 15:38 ` [PATCH 5.4 058/108] net/sched: act_skbmod: Skip non-Ethernet packets Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 059/108] ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 060/108] nvme-pci: dont WARN_ON in nvme_reset_work if ctrl.state is not RESETTING Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 061/108] Revert "USB: quirks: ignore remote wake-up on Fibocom L850-GL LTE modem" Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 062/108] afs: Fix tracepoint string placement with built-in AFS Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 063/108] r8169: Avoid duplicate sysfs entry creation error Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 064/108] nvme: set the PRACT bit when using Write Zeroes with T10 PI Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 065/108] sctp: update active_key for asoc when old key is being replaced Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 066/108] net: sched: cls_api: Fix the the wrong parameter Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 067/108] drm/panel: raspberrypi-touchscreen: Prevent double-free Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 068/108] proc: Avoid mixing integer types in mem_rw() Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 069/108] [PATCH] Revert "MIPS: add PMD table accounting into MIPSpmd_alloc_one" Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 070/108] s390/ftrace: fix ftrace_update_ftrace_func implementation Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 071/108] s390/boot: fix use of expolines in the DMA code Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 072/108] ALSA: usb-audio: Add missing proc text entry for BESPOKEN type Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 073/108] ALSA: usb-audio: Add registration quirk for JBL Quantum headsets Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 074/108] ALSA: sb: Fix potential ABBA deadlock in CSP driver Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 075/108] ALSA: hdmi: Expose all pins on MSI MS-7C94 board Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 076/108] xhci: Fix lost USB 2 remote wake Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 077/108] KVM: PPC: Book3S: Fix H_RTAS rets buffer overflow Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 078/108] KVM: PPC: Book3S HV Nested: Sanitise H_ENTER_NESTED TM state Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 079/108] usb: hub: Disable USB 3 device initiated lpm if exit latency is too high Greg Kroah-Hartman
2021-07-26 15:39 ` Greg Kroah-Hartman [this message]
2021-07-26 15:39 ` [PATCH 5.4 081/108] USB: usb-storage: Add LaCie Rugged USB3-FW to IGNORE_UAS Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 082/108] usb: max-3421: Prevent corruption of freed memory Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 083/108] usb: renesas_usbhs: Fix superfluous irqs happen after usb_pkt_pop() Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 084/108] USB: serial: option: add support for u-blox LARA-R6 family Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 085/108] USB: serial: cp210x: fix comments for GE CS1000 Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 086/108] USB: serial: cp210x: add ID for CEL EM3588 USB ZigBee stick Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 087/108] usb: dwc2: gadget: Fix sending zero length packet in DDMA mode Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 088/108] firmware/efi: Tell memblock about EFI iomem reservations Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 089/108] tracing/histogram: Rename "cpu" to "common_cpu" Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 090/108] tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 091/108] btrfs: check for missing device in btrfs_trim_fs Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 092/108] media: ngene: Fix out-of-bounds bug in ngene_command_config_free_buf() Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 093/108] ixgbe: Fix packet corruption due to missing DMA sync Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 094/108] selftest: use mmap instead of posix_memalign to allocate memory Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 095/108] userfaultfd: do not untag user pointers Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 096/108] hugetlbfs: fix mount mode command line processing Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 097/108] rbd: dont hold lock_rwsem while running_list is being drained Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 098/108] rbd: always kick acquire on "acquired" and "released" notifications Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 099/108] nds32: fix up stack guard gap Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 100/108] drm: Return -ENOTTY for non-drm ioctls Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 101/108] net: dsa: mv88e6xxx: use correct .stats_set_histogram() on Topaz Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 102/108] net: bcmgenet: ensure EXT_ENERGY_DET_MASK is clear Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 103/108] iio: accel: bma180: Use explicit member assignment Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 104/108] iio: accel: bma180: Fix BMA25x bandwidth register values Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 105/108] btrfs: compression: dont try to compress if we dont have enough pages Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 106/108] PCI: Mark AMD Navi14 GPU ATS as broken Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 107/108] perf inject: Close inject.output on exit Greg Kroah-Hartman
2021-07-26 15:39 ` [PATCH 5.4 108/108] xhci: add xhci_get_virt_ep() helper Greg Kroah-Hartman
2021-07-26 21:15 ` [PATCH 5.4 000/108] 5.4.136-rc1 review Florian Fainelli
2021-07-27 0:35 ` Shuah Khan
2021-07-27 8:49 ` Naresh Kamboju
2021-07-27 9:43 ` Jon Hunter
2021-07-27 16:06 ` Sudip Mukherjee
2021-07-27 18:02 ` Guenter Roeck
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