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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/watchdog/wdrtas.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/watchdog/wdrtas.c')
-rw-r--r-- | drivers/watchdog/wdrtas.c | 628 |
1 files changed, 628 insertions, 0 deletions
diff --git a/drivers/watchdog/wdrtas.c b/drivers/watchdog/wdrtas.c new file mode 100644 index 000000000..c00627825 --- /dev/null +++ b/drivers/watchdog/wdrtas.c @@ -0,0 +1,628 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * FIXME: add wdrtas_get_status and wdrtas_get_boot_status as soon as + * RTAS calls are available + */ + +/* + * RTAS watchdog driver + * + * (C) Copyright IBM Corp. 2005 + * device driver to exploit watchdog RTAS functions + * + * Authors : Utz Bacher <utz.bacher@de.ibm.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/reboot.h> +#include <linux/types.h> +#include <linux/watchdog.h> +#include <linux/uaccess.h> + +#include <asm/rtas.h> + +#define WDRTAS_MAGIC_CHAR 42 +#define WDRTAS_SUPPORTED_MASK (WDIOF_SETTIMEOUT | \ + WDIOF_MAGICCLOSE) + +MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>"); +MODULE_DESCRIPTION("RTAS watchdog driver"); +MODULE_LICENSE("GPL"); + +static bool wdrtas_nowayout = WATCHDOG_NOWAYOUT; +static atomic_t wdrtas_miscdev_open = ATOMIC_INIT(0); +static char wdrtas_expect_close; + +static int wdrtas_interval; + +#define WDRTAS_THERMAL_SENSOR 3 +static int wdrtas_token_get_sensor_state; +#define WDRTAS_SURVEILLANCE_IND 9000 +static int wdrtas_token_set_indicator; +#define WDRTAS_SP_SPI 28 +static int wdrtas_token_get_sp; +static int wdrtas_token_event_scan; + +#define WDRTAS_DEFAULT_INTERVAL 300 + +#define WDRTAS_LOGBUFFER_LEN 128 +static char wdrtas_logbuffer[WDRTAS_LOGBUFFER_LEN]; + + +/*** watchdog access functions */ + +/** + * wdrtas_set_interval - sets the watchdog interval + * @interval: new interval + * + * returns 0 on success, <0 on failures + * + * wdrtas_set_interval sets the watchdog keepalive interval by calling the + * RTAS function set-indicator (surveillance). The unit of interval is + * seconds. + */ + +static int wdrtas_set_interval(int interval) +{ + long result; + static int print_msg = 10; + + /* rtas uses minutes */ + interval = (interval + 59) / 60; + + result = rtas_call(wdrtas_token_set_indicator, 3, 1, NULL, + WDRTAS_SURVEILLANCE_IND, 0, interval); + if (result < 0 && print_msg) { + pr_err("setting the watchdog to %i timeout failed: %li\n", + interval, result); + print_msg--; + } + + return result; +} + +#define WDRTAS_SP_SPI_LEN 4 + +/** + * wdrtas_get_interval - returns the current watchdog interval + * @fallback_value: value (in seconds) to use, if the RTAS call fails + * + * returns the interval + * + * wdrtas_get_interval returns the current watchdog keepalive interval + * as reported by the RTAS function ibm,get-system-parameter. The unit + * of the return value is seconds. + */ +static int wdrtas_get_interval(int fallback_value) +{ + long result; + char value[WDRTAS_SP_SPI_LEN]; + + spin_lock(&rtas_data_buf_lock); + memset(rtas_data_buf, 0, WDRTAS_SP_SPI_LEN); + result = rtas_call(wdrtas_token_get_sp, 3, 1, NULL, + WDRTAS_SP_SPI, __pa(rtas_data_buf), + WDRTAS_SP_SPI_LEN); + + memcpy(value, rtas_data_buf, WDRTAS_SP_SPI_LEN); + spin_unlock(&rtas_data_buf_lock); + + if (value[0] != 0 || value[1] != 2 || value[3] != 0 || result < 0) { + pr_warn("could not get sp_spi watchdog timeout (%li). Continuing\n", + result); + return fallback_value; + } + + /* rtas uses minutes */ + return ((int)value[2]) * 60; +} + +/** + * wdrtas_timer_start - starts watchdog + * + * wdrtas_timer_start starts the watchdog by calling the RTAS function + * set-interval (surveillance) + */ +static void wdrtas_timer_start(void) +{ + wdrtas_set_interval(wdrtas_interval); +} + +/** + * wdrtas_timer_stop - stops watchdog + * + * wdrtas_timer_stop stops the watchdog timer by calling the RTAS function + * set-interval (surveillance) + */ +static void wdrtas_timer_stop(void) +{ + wdrtas_set_interval(0); +} + +/** + * wdrtas_timer_keepalive - resets watchdog timer to keep system alive + * + * wdrtas_timer_keepalive restarts the watchdog timer by calling the + * RTAS function event-scan and repeats these calls as long as there are + * events available. All events will be dumped. + */ +static void wdrtas_timer_keepalive(void) +{ + long result; + + do { + result = rtas_call(wdrtas_token_event_scan, 4, 1, NULL, + RTAS_EVENT_SCAN_ALL_EVENTS, 0, + (void *)__pa(wdrtas_logbuffer), + WDRTAS_LOGBUFFER_LEN); + if (result < 0) + pr_err("event-scan failed: %li\n", result); + if (result == 0) + print_hex_dump(KERN_INFO, "dumping event, data: ", + DUMP_PREFIX_OFFSET, 16, 1, + wdrtas_logbuffer, WDRTAS_LOGBUFFER_LEN, false); + } while (result == 0); +} + +/** + * wdrtas_get_temperature - returns current temperature + * + * returns temperature or <0 on failures + * + * wdrtas_get_temperature returns the current temperature in Fahrenheit. It + * uses the RTAS call get-sensor-state, token 3 to do so + */ +static int wdrtas_get_temperature(void) +{ + int result; + int temperature = 0; + + result = rtas_get_sensor(WDRTAS_THERMAL_SENSOR, 0, &temperature); + + if (result < 0) + pr_warn("reading the thermal sensor failed: %i\n", result); + else + temperature = ((temperature * 9) / 5) + 32; /* fahrenheit */ + + return temperature; +} + +/** + * wdrtas_get_status - returns the status of the watchdog + * + * returns a bitmask of defines WDIOF_... as defined in + * include/linux/watchdog.h + */ +static int wdrtas_get_status(void) +{ + return 0; /* TODO */ +} + +/** + * wdrtas_get_boot_status - returns the reason for the last boot + * + * returns a bitmask of defines WDIOF_... as defined in + * include/linux/watchdog.h, indicating why the watchdog rebooted the system + */ +static int wdrtas_get_boot_status(void) +{ + return 0; /* TODO */ +} + +/*** watchdog API and operations stuff */ + +/* wdrtas_write - called when watchdog device is written to + * @file: file structure + * @buf: user buffer with data + * @len: amount to data written + * @ppos: position in file + * + * returns the number of successfully processed characters, which is always + * the number of bytes passed to this function + * + * wdrtas_write processes all the data given to it and looks for the magic + * character 'V'. This character allows the watchdog device to be closed + * properly. + */ +static ssize_t wdrtas_write(struct file *file, const char __user *buf, + size_t len, loff_t *ppos) +{ + int i; + char c; + + if (!len) + goto out; + + if (!wdrtas_nowayout) { + wdrtas_expect_close = 0; + /* look for 'V' */ + for (i = 0; i < len; i++) { + if (get_user(c, buf + i)) + return -EFAULT; + /* allow to close device */ + if (c == 'V') + wdrtas_expect_close = WDRTAS_MAGIC_CHAR; + } + } + + wdrtas_timer_keepalive(); + +out: + return len; +} + +/** + * wdrtas_ioctl - ioctl function for the watchdog device + * @file: file structure + * @cmd: command for ioctl + * @arg: argument pointer + * + * returns 0 on success, <0 on failure + * + * wdrtas_ioctl implements the watchdog API ioctls + */ + +static long wdrtas_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int __user *argp = (void __user *)arg; + int i; + static const struct watchdog_info wdinfo = { + .options = WDRTAS_SUPPORTED_MASK, + .firmware_version = 0, + .identity = "wdrtas", + }; + + switch (cmd) { + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &wdinfo, sizeof(wdinfo))) + return -EFAULT; + return 0; + + case WDIOC_GETSTATUS: + i = wdrtas_get_status(); + return put_user(i, argp); + + case WDIOC_GETBOOTSTATUS: + i = wdrtas_get_boot_status(); + return put_user(i, argp); + + case WDIOC_GETTEMP: + if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE) + return -EOPNOTSUPP; + + i = wdrtas_get_temperature(); + return put_user(i, argp); + + case WDIOC_SETOPTIONS: + if (get_user(i, argp)) + return -EFAULT; + if (i & WDIOS_DISABLECARD) + wdrtas_timer_stop(); + if (i & WDIOS_ENABLECARD) { + wdrtas_timer_keepalive(); + wdrtas_timer_start(); + } + /* not implemented. Done by H8 + if (i & WDIOS_TEMPPANIC) { + } */ + return 0; + + case WDIOC_KEEPALIVE: + wdrtas_timer_keepalive(); + return 0; + + case WDIOC_SETTIMEOUT: + if (get_user(i, argp)) + return -EFAULT; + + if (wdrtas_set_interval(i)) + return -EINVAL; + + wdrtas_timer_keepalive(); + + if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) + wdrtas_interval = i; + else + wdrtas_interval = wdrtas_get_interval(i); + fallthrough; + + case WDIOC_GETTIMEOUT: + return put_user(wdrtas_interval, argp); + + default: + return -ENOTTY; + } +} + +/** + * wdrtas_open - open function of watchdog device + * @inode: inode structure + * @file: file structure + * + * returns 0 on success, -EBUSY if the file has been opened already, <0 on + * other failures + * + * function called when watchdog device is opened + */ +static int wdrtas_open(struct inode *inode, struct file *file) +{ + /* only open once */ + if (atomic_inc_return(&wdrtas_miscdev_open) > 1) { + atomic_dec(&wdrtas_miscdev_open); + return -EBUSY; + } + + wdrtas_timer_start(); + wdrtas_timer_keepalive(); + + return stream_open(inode, file); +} + +/** + * wdrtas_close - close function of watchdog device + * @inode: inode structure + * @file: file structure + * + * returns 0 on success + * + * close function. Always succeeds + */ +static int wdrtas_close(struct inode *inode, struct file *file) +{ + /* only stop watchdog, if this was announced using 'V' before */ + if (wdrtas_expect_close == WDRTAS_MAGIC_CHAR) + wdrtas_timer_stop(); + else { + pr_warn("got unexpected close. Watchdog not stopped.\n"); + wdrtas_timer_keepalive(); + } + + wdrtas_expect_close = 0; + atomic_dec(&wdrtas_miscdev_open); + return 0; +} + +/** + * wdrtas_temp_read - gives back the temperature in fahrenheit + * @file: file structure + * @buf: user buffer + * @count: number of bytes to be read + * @ppos: position in file + * + * returns always 1 or -EFAULT in case of user space copy failures, <0 on + * other failures + * + * wdrtas_temp_read gives the temperature to the users by copying this + * value as one byte into the user space buffer. The unit is Fahrenheit... + */ +static ssize_t wdrtas_temp_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + int temperature = 0; + + temperature = wdrtas_get_temperature(); + if (temperature < 0) + return temperature; + + if (copy_to_user(buf, &temperature, 1)) + return -EFAULT; + + return 1; +} + +/** + * wdrtas_temp_open - open function of temperature device + * @inode: inode structure + * @file: file structure + * + * returns 0 on success, <0 on failure + * + * function called when temperature device is opened + */ +static int wdrtas_temp_open(struct inode *inode, struct file *file) +{ + return stream_open(inode, file); +} + +/** + * wdrtas_temp_close - close function of temperature device + * @inode: inode structure + * @file: file structure + * + * returns 0 on success + * + * close function. Always succeeds + */ +static int wdrtas_temp_close(struct inode *inode, struct file *file) +{ + return 0; +} + +/** + * wdrtas_reboot - reboot notifier function + * @nb: notifier block structure + * @code: reboot code + * @ptr: unused + * + * returns NOTIFY_DONE + * + * wdrtas_reboot stops the watchdog in case of a reboot + */ +static int wdrtas_reboot(struct notifier_block *this, + unsigned long code, void *ptr) +{ + if (code == SYS_DOWN || code == SYS_HALT) + wdrtas_timer_stop(); + + return NOTIFY_DONE; +} + +/*** initialization stuff */ + +static const struct file_operations wdrtas_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = wdrtas_write, + .unlocked_ioctl = wdrtas_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .open = wdrtas_open, + .release = wdrtas_close, +}; + +static struct miscdevice wdrtas_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &wdrtas_fops, +}; + +static const struct file_operations wdrtas_temp_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .read = wdrtas_temp_read, + .open = wdrtas_temp_open, + .release = wdrtas_temp_close, +}; + +static struct miscdevice wdrtas_tempdev = { + .minor = TEMP_MINOR, + .name = "temperature", + .fops = &wdrtas_temp_fops, +}; + +static struct notifier_block wdrtas_notifier = { + .notifier_call = wdrtas_reboot, +}; + +/** + * wdrtas_get_tokens - reads in RTAS tokens + * + * returns 0 on success, <0 on failure + * + * wdrtas_get_tokens reads in the tokens for the RTAS calls used in + * this watchdog driver. It tolerates, if "get-sensor-state" and + * "ibm,get-system-parameter" are not available. + */ +static int wdrtas_get_tokens(void) +{ + wdrtas_token_get_sensor_state = rtas_token("get-sensor-state"); + if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE) { + pr_warn("couldn't get token for get-sensor-state. Trying to continue without temperature support.\n"); + } + + wdrtas_token_get_sp = rtas_token("ibm,get-system-parameter"); + if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) { + pr_warn("couldn't get token for ibm,get-system-parameter. Trying to continue with a default timeout value of %i seconds.\n", + WDRTAS_DEFAULT_INTERVAL); + } + + wdrtas_token_set_indicator = rtas_token("set-indicator"); + if (wdrtas_token_set_indicator == RTAS_UNKNOWN_SERVICE) { + pr_err("couldn't get token for set-indicator. Terminating watchdog code.\n"); + return -EIO; + } + + wdrtas_token_event_scan = rtas_token("event-scan"); + if (wdrtas_token_event_scan == RTAS_UNKNOWN_SERVICE) { + pr_err("couldn't get token for event-scan. Terminating watchdog code.\n"); + return -EIO; + } + + return 0; +} + +/** + * wdrtas_unregister_devs - unregisters the misc dev handlers + * + * wdrtas_register_devs unregisters the watchdog and temperature watchdog + * misc devs + */ +static void wdrtas_unregister_devs(void) +{ + misc_deregister(&wdrtas_miscdev); + if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE) + misc_deregister(&wdrtas_tempdev); +} + +/** + * wdrtas_register_devs - registers the misc dev handlers + * + * returns 0 on success, <0 on failure + * + * wdrtas_register_devs registers the watchdog and temperature watchdog + * misc devs + */ +static int wdrtas_register_devs(void) +{ + int result; + + result = misc_register(&wdrtas_miscdev); + if (result) { + pr_err("couldn't register watchdog misc device. Terminating watchdog code.\n"); + return result; + } + + if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE) { + result = misc_register(&wdrtas_tempdev); + if (result) { + pr_warn("couldn't register watchdog temperature misc device. Continuing without temperature support.\n"); + wdrtas_token_get_sensor_state = RTAS_UNKNOWN_SERVICE; + } + } + + return 0; +} + +/** + * wdrtas_init - init function of the watchdog driver + * + * returns 0 on success, <0 on failure + * + * registers the file handlers and the reboot notifier + */ +static int __init wdrtas_init(void) +{ + if (wdrtas_get_tokens()) + return -ENODEV; + + if (wdrtas_register_devs()) + return -ENODEV; + + if (register_reboot_notifier(&wdrtas_notifier)) { + pr_err("could not register reboot notifier. Terminating watchdog code.\n"); + wdrtas_unregister_devs(); + return -ENODEV; + } + + if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) + wdrtas_interval = WDRTAS_DEFAULT_INTERVAL; + else + wdrtas_interval = wdrtas_get_interval(WDRTAS_DEFAULT_INTERVAL); + + return 0; +} + +/** + * wdrtas_exit - exit function of the watchdog driver + * + * unregisters the file handlers and the reboot notifier + */ +static void __exit wdrtas_exit(void) +{ + if (!wdrtas_nowayout) + wdrtas_timer_stop(); + + wdrtas_unregister_devs(); + + unregister_reboot_notifier(&wdrtas_notifier); +} + +module_init(wdrtas_init); +module_exit(wdrtas_exit); |