Maciej W. Rozycki
0e2b4c7ebd
serial: 8250: Define RX trigger levels for OxSemi 950 devices ...
[ Upstream commit d7aff291d069c4418285f3c8ee27b0ff67ce5998 ]
Oxford Semiconductor 950 serial port devices have a 128-byte FIFO and in
the enhanced (650) mode, which we select in `autoconfig_has_efr' with
the ECB bit set in the EFR register, they support the receive interrupt
trigger level selectable with FCR bits 7:6 from the set of 16, 32, 112,
120. This applies to the original OX16C950 discrete UART[1] as well as
950 cores embedded into more complex devices.
For these devices we set the default to 112, which sets an excessively
high level of 112 or 7/8 of the FIFO capacity, unlike with other port
types where we choose at most 1/2 of their respective FIFO capacities.
Additionally we don't make the trigger level configurable. Consequently
frequent input overruns happen with high bit rates where hardware flow
control cannot be used (e.g. terminal applications) even with otherwise
highly-performant systems.
Lower the default receive interrupt trigger level to 32 then, and make
it configurable. Document the trigger levels along with other port
types, including the set of 16, 32, 64, 112 for the transmit interrupt
as well[2].
References:
[1] "OX16C950 rev B High Performance UART with 128 byte FIFOs", Oxford
Semiconductor, Inc., DS-0031, Sep 05, Table 10: "Receiver Trigger
Levels", p. 22
[2] same, Table 9: "Transmit Interrupt Trigger Levels", p. 22
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106260608480.37803@angie.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-22 11:43:06 +02:00
include/uapi/linux/byteorder, swab: force inlining of some byteswap operations
2016-03-17 15:09:34 -07:00
can: bcm: add support for CAN FD frames
2016-06-17 15:39:46 +02:00
install several missing uapi headers
2020-08-21 11:01:49 +02:00
media: dvb_frontend: fix return values for FE_SET_PROPERTY
2020-06-30 15:38:35 -04:00
install several missing uapi headers
2020-08-21 11:01:49 +02:00
HSI: hsi_char.h: use __u32 from linux/types.h
2016-08-22 22:43:35 +02:00
iio: electricalconductivity: add IIO_ELECTRICALCONDUCTIVITY type
2016-05-29 20:03:21 +01:00
isdn/capi: check message length in capi_write()
2019-09-21 07:14:01 +02:00
mmc: fix compilation of user API
2020-06-11 09:22:20 +02:00
uapi: nfnetlink_cthelper.h: fix userspace compilation error
2021-03-17 16:10:13 +01:00
netfilter: fix include files for compilation
2015-11-23 17:54:38 +01:00
netfilter: fix include files for compilation
2015-11-23 17:54:38 +01:00
netfilter: fix include files for compilation
2015-11-23 17:54:38 +01:00
netfilter: fix include files for compilation
2015-11-23 17:54:38 +01:00
drivers: md: use ktime_get_real_seconds()
2016-01-06 11:39:53 +11:00
spi: uapi: spidev: add missing ioctl header
2017-11-02 09:49:13 +01:00
uapi: export tc_skbmod.h
2016-12-05 19:43:02 -05:00
USB: replace hardcode maximum usb string length by definition
2021-03-24 10:59:24 +01:00
include/uapi/linux/agpgart.h: include stdlib.h in userspace
2015-12-10 12:33:23 +01:00
Revert "include/uapi/linux/atm_zatm.h: include linux/time.h"
2016-11-13 12:35:13 -05:00
Merge branch 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit
2016-10-04 14:21:41 -07:00
autofs4: move linux/auto_dev-ioctl.h to uapi/linux
2016-10-11 15:06:31 -07:00
autofs: move inclusion of linux/limits.h to uapi
2016-10-11 15:06:31 -07:00
autofs4: fix some white space errors
2016-03-15 16:55:16 -07:00
batman-adv: add backbone table netlink support
2016-08-09 07:54:43 +02:00
uapi: includes linux/types.h before exporting files
2020-08-21 11:01:49 +02:00
mtd: provide proper 32/64-bit compat_ioctl() support for BLKPG
2015-09-29 13:37:04 -07:00
bpf: add helper to invalidate hash
2016-09-23 08:40:28 -04:00
bpf: introduce BPF_PROG_TYPE_PERF_EVENT program type
2016-09-02 10:46:44 -07:00
net: bpqether.h: remove if_ether.h guard
2016-11-13 00:57:53 -05:00
ipmi: add an Aspeed BT IPMI BMC driver
2016-09-29 19:05:06 -05:00
Btrfs: catch invalid free space trees
2016-10-03 18:52:14 +02:00
uapi: includes linux/types.h before exporting files
2020-08-21 11:01:49 +02:00
can: raw: raw_setsockopt: limit number of can_filter that can be set
2016-12-07 10:45:57 +01:00
uapi: move forward declarations of internal structures
2016-08-02 17:31:41 -04:00
uapi linux/coda_psdev.h: move upc_req definition from uapi to kernel side headers
2019-08-06 18:29:38 +02:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
coresight: do not use the BIT() macro in the UAPI header
2020-04-13 10:32:53 +02:00
uapi: includes linux/types.h before exporting files
2020-08-21 11:01:49 +02:00
net/devlink: Add E-Switch mode control
2016-07-02 14:40:40 -04:00
dlm: fix lvb copy for user locks
2015-08-25 14:41:50 -05:00
dm: add infrastructure for DAX support
2016-07-20 23:49:49 -04:00
dma-buf: Add ioctls to allow userspace to flush
2016-02-12 16:01:32 +01:00
quota: add new quotactl Q_XGETNEXTQUOTA
2016-02-08 11:21:50 +11:00
bpf, elf: add official ELF machine define for eBPF
2016-07-20 12:37:39 -07:00
powerpc updates for 4.8 #2
2016-08-05 09:00:54 -04:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
eventpoll.h: fix epoll event masks
2018-03-22 09:17:38 +01:00
vfs: add a FALLOC_FL_UNSHARE mode to fallocate to unshare a range of blocks
2016-10-03 09:11:14 -07:00
net: Add l3mdev rule
2016-06-08 11:36:02 -07:00
fs: Better permission checking for submounts
2017-03-15 10:02:44 +08:00
fuse: Add FOPEN_STREAM to use stream_open()
2019-06-11 12:22:49 +02:00
sched: align nlattr properly when needed
2016-04-26 12:00:49 -04:00
openvswitch: allow management from inside user namespaces
2016-02-11 09:53:19 -05:00
gfs2: change gfs2 readdir cookie
2015-12-14 12:19:37 -06:00
gpio: userspace ABI for reading GPIO line events
2016-06-15 09:29:17 +02:00
gtp: #define _UAPI_LINUX_GTP_H_ and not _UAPI_LINUX_GTP_H__
2016-06-07 16:25:49 -07:00
keys, trusted: select hash algorithm for TPM2 chips
2015-12-20 15:27:12 +02:00
tools: hv: report ENOSPC errors in hv_fcopy_daemon
2015-12-14 19:12:21 -08:00
i2c-dev: Fix typo in ioctl name reference
2015-10-23 23:26:43 +02:00
i2c: smbus: add SMBus Host Notify support
2016-06-17 13:24:05 +02:00
ipv6: RFC 4884 partial support for SIT/GRE tunnels
2016-06-18 22:11:39 -07:00
uapi glibc compat: fix outer guard of net device flags enum
2016-12-06 10:43:32 -05:00
arcnet: fix indentation of if_arcnet.h
2015-09-23 08:44:22 +02:00
net: bridge: export vlan flags with the stats
2016-08-18 23:18:42 -07:00
uapi/if_ether.h: move __UAPI_DEF_ETHHDR libc define
2019-02-20 10:18:35 +01:00
net: Update API for VF vlan protocol 802.1ad support
2016-09-24 08:01:26 -04:00
macsec: limit ICV length to 16 octets
2016-07-25 10:55:39 -07:00
net: l2tp: deprecate PPPOL2TP_MSG_* in favour of L2TP_MSG_*
2020-05-27 16:41:53 +02:00
include/uapi/linux/if_pppox.h: include linux/in.h and linux/in6.h
2016-08-22 16:25:15 -07:00
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2016-09-25 23:34:19 +02:00
ila: add checksum neutral ILA translations
2016-04-26 01:27:07 -04:00
calipso: Set the calipso socket label to match the secattr.
2016-06-27 15:02:51 -04:00
tcp_bbr: add BBR congestion control
2016-09-21 00:23:01 -04:00
Input: restore EV_ABS ABS_RESERVED
2019-01-13 10:03:48 +01:00
HID: intel-ish-hid: ISH HID client driver
2016-08-17 11:13:08 +02:00
ipv4: add option to drop gratuitous ARP packets
2016-02-11 04:27:35 -05:00
netfilter/ipvs: use nla_put_u64_64bit()
2016-04-25 15:09:11 -04:00
ipv6 addrconf: implement RFC7559 router solicitation backoff
2016-09-30 01:54:28 -04:00
net: ipv6: RTF_PCPU should not be settable from userspace
2017-05-03 08:36:36 -07:00
include/uapi/linux/ipx.h: fix conflicting defitions with glibc netipx/ipx.h
2016-08-22 16:25:15 -07:00
install several missing uapi headers
2020-08-21 11:01:49 +02:00
kcm: Kernel Connection Multiplexor module
2016-03-09 16:36:14 -05:00
kernel: add kcov code coverage
2016-03-22 15:36:02 -07:00
proc: export idle flag via kpageflags
2015-09-10 13:29:01 -07:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
arm64/kexec: Add core kexec support
2016-06-27 16:31:25 +01:00
KEYS: Add KEYCTL_DH_COMPUTE command
2016-04-12 19:54:58 +01:00
x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
2020-06-20 10:24:14 +02:00
uapi: fix linux/if_pppol2tp.h userspace compilation errors
2020-06-03 08:16:33 +02:00
uapi/if_ether.h: move __UAPI_DEF_ETHHDR libc define
2019-02-20 10:18:35 +01:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
[media] lirc.h: remove several unused ioctls
2016-07-11 10:49:52 -03:00
block: loop: introduce ioctl command of LOOP_SET_DIRECT_IO
2015-09-23 11:01:16 -06:00
libnl: nla_put_be64(): align on a 64-bit area
2016-04-23 20:13:24 -04:00
dax: define a unified inode/address_space for device-dax mappings
2016-08-23 22:58:51 -07:00
[media] media: Add 1X16 16-bit raw bayer media bus code definitions
2016-09-09 11:16:36 -03:00
[media] v4l2-core: Add support for touch devices
2016-08-23 16:28:04 -03:00
sys_membarrier(): system-wide memory barrier (generic, x86)
2015-09-11 15:21:34 -07:00
misc: mic: Update MIC host daemon with COSM changes
2015-10-04 12:54:54 +01:00
net: Add mask for Control register 10Mbps speed
2016-08-12 16:57:20 -07:00
net: ipmr: fix code and comment style
2015-11-23 15:06:38 -05:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
block: Move SECTOR_SIZE and SECTOR_SHIFT definitions into <linux/blkdev.h>
2020-09-12 11:47:36 +02:00
libnvdimm: fix SMART Health DSM payload definition
2016-08-15 11:07:21 -07:00
libnl: nla_put_msecs(): align on a 64-bit area
2016-04-23 20:13:24 -04:00
sock: accept SO_TIMESTAMPING flags in socket cmsg
2016-04-04 15:50:30 -04:00
netconf: add macro to represent all attributes
2016-03-13 21:54:44 -04:00
netfilter: fix include files for compilation
2015-11-23 17:54:38 +01:00
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
netlink: Add comment to warn about deprecated netlink rings attribute request
2016-06-16 14:00:50 -07:00
NFC: netlink: Add missing NFC_ATTR comments
2015-10-27 03:55:10 +01:00
nfs: use btrfs ioctl defintions for clone
2015-11-23 21:53:08 -05:00
nfs: add a new NFS4_OPEN_RESULT_MAY_NOTIFY_LOCK constant
2016-09-26 15:20:37 -04:00
nilfs2: move ioctl interface and disk layout to uapi separately
2016-08-02 19:35:21 -04:00
nilfs2: do not use unexported cpu_to_le32()/le32_to_cpu() in uapi header
2019-07-21 09:06:04 +02:00
cfg80211: further limit wiphy names to 64 bytes
2018-06-06 16:44:33 +02:00
nsfs: add ioctl to get a parent namespace
2016-09-22 19:59:41 -05:00
NVMe: Allow user initiated rescan
2016-05-17 17:14:21 -06:00
openvswitch: 802.1ad uapi changes.
2016-09-08 17:10:27 -07:00
uapi: fix linux/packet_diag.h userspace compilation error
2017-03-22 12:43:34 +01:00
PCI: Make PCI_ROM_ADDRESS_MASK a 32-bit constant
2018-04-08 12:12:43 +02:00
perf core: Per event callchain limit
2016-05-30 12:41:44 -03:00
net: cls_bpf: limit hardware offload by software-only flag
2016-09-21 19:50:02 -04:00
net_sched: sch_fq: account for schedule/timers drifts
2016-09-23 07:19:06 -04:00
posix_acl: uapi header split
2016-09-27 21:52:00 -04:00
posix_acl: uapi header split
2016-09-27 21:52:00 -04:00
uapi: includes linux/types.h before exporting files
2020-08-21 11:01:49 +02:00
x86/speculation: Add prctl() control for indirect branch speculation
2019-05-14 19:19:39 +02:00
arm/arm64: KVM: Add PSCI_VERSION helper
2018-04-20 08:21:04 +02:00
ptp: Add PTP_SYS_OFFSET_PRECISE for driver crosstimestamping
2016-03-03 14:23:43 -08:00
seccomp, ptrace: add support for dumping seccomp filters
2015-10-27 19:55:13 -07:00
uapi: includes linux/types.h before exporting files
2020-08-21 11:01:49 +02:00
fs/quota: use nla_put_u64_64bit()
2016-04-26 12:00:48 -04:00
random: add new ioctl RNDRESEEDCRNG
2018-04-24 09:34:16 +02:00
uapi: fix linux/rds.h userspace compilation errors
2017-11-21 09:23:28 +01:00
rfkill: Update userspace API documentation
2016-02-24 09:04:25 +01:00
rapidio: add RapidIO channelized messaging driver
2016-08-02 19:35:31 -04:00
rapidio/mport_cdev: fix uapi type definitions
2016-05-05 17:38:53 -07:00
rtnetlink: Add rtnexthop offload flag to compare mask
2016-10-19 11:07:57 -04:00
sched: new clone flag CLONE_NEWCGROUP for cgroup namespace
2016-02-16 13:04:58 -05:00
misc: mic: SCIF RMA header file and IOCTL changes
2015-10-04 12:54:54 +01:00
efifb: Add support for 64-bit frame buffer addresses
2015-10-12 14:20:06 +01:00
sctp: Export struct sctp_info to userspace
2016-08-08 12:51:58 -07:00
seccomp: Add filter flag to opt-out of SSB mitigation
2018-05-22 16:58:01 +02:00
capabilities: add a securebit to disable PR_CAP_AMBIENT_RAISE
2015-09-04 16:54:41 -07:00
serial: support 16-bit register interface for console
2015-12-13 19:59:48 -08:00
TTY and Serial driver update for 4.7-rc1
2016-05-20 20:57:27 -07:00
serial: 8250: Define RX trigger levels for OxSemi 950 devices
2021-09-22 11:43:06 +02:00
[media] input: serio - add new protocol for the Pulse-Eight USB-CEC Adapter
2016-07-12 13:42:10 -03:00
signals/sigaltstack: Change SS_AUTODISARM to (1U << 31)
2016-05-04 08:34:14 +02:00
tcp: tcp_fragment() should apply sane memory limits
2019-06-17 19:53:32 +02:00
sock_diag: add SK_MEMINFO_DROPS
2016-04-04 22:11:20 -04:00
include/uapi/linux/sockios.h: mark SIOCRTMSG unused
2016-01-05 16:44:06 -05:00
uapi/linux/stddef.h: Provide __always_inline to userspace headers
2016-03-30 12:50:17 +02:00
stm class: Introduce an abstraction for System Trace Module devices
2015-10-04 20:28:58 +01:00
byteswap: try to avoid __builtin_constant_p gcc bug
2016-05-05 17:38:53 -07:00
dma-buf/sync_file: fix documentation error
2016-09-20 18:12:38 +05:30
uapi: move constants from <linux/kernel.h> to <linux/const.h>
2021-01-09 13:35:49 +01:00
target/user: Report capability of handling out-of-order completions to userspace
2016-03-10 21:49:09 -08:00
tcp: export data delivery rate
2016-09-21 00:23:00 -04:00
libnl: nla_put_msecs(): align on a 64-bit area
2016-04-23 20:13:24 -04:00
tipc: introduce constants for tipc address validation
2016-07-26 14:26:42 -07:00
tipc: Avoid copying bytes beyond the supplied data
2019-06-11 12:22:34 +02:00
tipc: add the ability to get UDP options via netlink
2016-08-26 21:38:41 -07:00
tty: actually undefine superseded ASYNC flags
2021-05-22 10:40:24 +02:00
gtp: add initial driver for datapath of GPRS Tunneling Protocol (GTP-U)
2016-05-10 12:25:04 -04:00
Input: uinput - rework ABS validation
2015-12-18 17:48:51 -08:00
usb: devio: Add ioctl to disallow detaching kernel USB drivers.
2016-03-05 12:05:01 -08:00
userfaultfd: remove kernel header include from uapi header
2015-10-01 21:42:35 -04:00
Input: add userio module
2015-10-27 18:55:31 -07:00
lib/uuid.c: remove FSF address
2016-05-20 17:58:30 -07:00
[media] media: v4l: Dual license v4l2-common.h under GPL v2 and BSD licenses
2016-02-01 08:47:05 -02:00
[media] v4l: add V4L2_CID_MPEG_VIDEO_FORCE_KEY_FRAME
2016-02-19 08:10:35 -02:00
[media] SDI: add flag for SDI formats and SMPTE 125M definition
2016-09-19 14:34:41 -03:00
vfio/pci: Intel IGD host and LCP bridge config space access
2016-02-22 16:10:09 -07:00
vhost: new device IOTLB API
2016-08-02 16:53:54 +03:00
videodev2.h: go back to limited range Y'CbCr for SRGB and, ADOBERGB
2017-02-23 17:44:37 +01:00
virtio_balloon: export 'available' memory to balloon statistics
2016-03-17 15:09:34 -07:00
virtio_blk: VIRTIO_BLK_F_WCE->VIRTIO_BLK_F_FLUSH
2016-03-02 17:01:59 +02:00
virtio: new feature to detect IOMMU device quirk
2016-08-01 21:44:52 +03:00
include/uapi/linux/virtio_gpu.h: use __u8 from <linux/types.h>
2015-12-10 12:33:23 +01:00
VSOCK: Introduce virtio_vsock_common.ko
2016-08-02 02:57:29 +03:00
virtio_net: add _UAPI prefix to virtio_net header guards
2016-06-10 23:03:55 -07:00
virtio-vsock: fix include guard typo
2016-08-09 13:42:38 +03:00
tty: vt, remove reduntant check
2016-04-30 09:26:55 -07:00
tpm: Proxy driver for supporting multiple emulated TPMs
2016-06-25 17:26:35 +03:00
wext: reformat struct/union declarations
2016-06-09 10:14:39 +02:00
xfrm: fix header file comment reference to struct xfrm_replay_state_esn
2016-09-09 09:10:07 +02:00
0e2b4c7ebd