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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/watchdog/nv_tco.c
downloadlinux-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/nv_tco.c')
-rw-r--r--drivers/watchdog/nv_tco.c515
1 files changed, 515 insertions, 0 deletions
diff --git a/drivers/watchdog/nv_tco.c b/drivers/watchdog/nv_tco.c
new file mode 100644
index 000000000..f6902a337
--- /dev/null
+++ b/drivers/watchdog/nv_tco.c
@@ -0,0 +1,515 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * nv_tco 0.01: TCO timer driver for NV chipsets
+ *
+ * (c) Copyright 2005 Google Inc., All Rights Reserved.
+ *
+ * Based off i8xx_tco.c:
+ * (c) Copyright 2000 kernel concepts <nils@kernelconcepts.de>, All Rights
+ * Reserved.
+ * https://www.kernelconcepts.de
+ *
+ * TCO timer driver for NV chipsets
+ * based on softdog.c by Alan Cox <alan@redhat.com>
+ */
+
+/*
+ * Includes, defines, variables, module parameters, ...
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+
+#include "nv_tco.h"
+
+/* Module and version information */
+#define TCO_VERSION "0.01"
+#define TCO_MODULE_NAME "NV_TCO"
+#define TCO_DRIVER_NAME TCO_MODULE_NAME ", v" TCO_VERSION
+
+/* internal variables */
+static unsigned int tcobase;
+static DEFINE_SPINLOCK(tco_lock); /* Guards the hardware */
+static unsigned long timer_alive;
+static char tco_expect_close;
+static struct pci_dev *tco_pci;
+
+/* the watchdog platform device */
+static struct platform_device *nv_tco_platform_device;
+
+/* module parameters */
+#define WATCHDOG_HEARTBEAT 30 /* 30 sec default heartbeat (2<heartbeat<39) */
+static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (2<heartbeat<39, "
+ "default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"
+ " (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+/*
+ * Some TCO specific functions
+ */
+static inline unsigned char seconds_to_ticks(int seconds)
+{
+ /* the internal timer is stored as ticks which decrement
+ * every 0.6 seconds */
+ return (seconds * 10) / 6;
+}
+
+static void tco_timer_start(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inl(TCO_CNT(tcobase));
+ val &= ~TCO_CNT_TCOHALT;
+ outl(val, TCO_CNT(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_stop(void)
+{
+ u32 val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inl(TCO_CNT(tcobase));
+ val |= TCO_CNT_TCOHALT;
+ outl(val, TCO_CNT(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static void tco_timer_keepalive(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&tco_lock, flags);
+ outb(0x01, TCO_RLD(tcobase));
+ spin_unlock_irqrestore(&tco_lock, flags);
+}
+
+static int tco_timer_set_heartbeat(int t)
+{
+ int ret = 0;
+ unsigned char tmrval;
+ unsigned long flags;
+ u8 val;
+
+ /*
+ * note seconds_to_ticks(t) > t, so if t > 0x3f, so is
+ * tmrval=seconds_to_ticks(t). Check that the count in seconds isn't
+ * out of range on it's own (to avoid overflow in tmrval).
+ */
+ if (t < 0 || t > 0x3f)
+ return -EINVAL;
+ tmrval = seconds_to_ticks(t);
+
+ /* "Values of 0h-3h are ignored and should not be attempted" */
+ if (tmrval > 0x3f || tmrval < 0x04)
+ return -EINVAL;
+
+ /* Write new heartbeat to watchdog */
+ spin_lock_irqsave(&tco_lock, flags);
+ val = inb(TCO_TMR(tcobase));
+ val &= 0xc0;
+ val |= tmrval;
+ outb(val, TCO_TMR(tcobase));
+ val = inb(TCO_TMR(tcobase));
+
+ if ((val & 0x3f) != tmrval)
+ ret = -EINVAL;
+ spin_unlock_irqrestore(&tco_lock, flags);
+
+ if (ret)
+ return ret;
+
+ heartbeat = t;
+ return 0;
+}
+
+/*
+ * /dev/watchdog handling
+ */
+
+static int nv_tco_open(struct inode *inode, struct file *file)
+{
+ /* /dev/watchdog can only be opened once */
+ if (test_and_set_bit(0, &timer_alive))
+ return -EBUSY;
+
+ /* Reload and activate timer */
+ tco_timer_keepalive();
+ tco_timer_start();
+ return stream_open(inode, file);
+}
+
+static int nv_tco_release(struct inode *inode, struct file *file)
+{
+ /* Shut off the timer */
+ if (tco_expect_close == 42) {
+ tco_timer_stop();
+ } else {
+ pr_crit("Unexpected close, not stopping watchdog!\n");
+ tco_timer_keepalive();
+ }
+ clear_bit(0, &timer_alive);
+ tco_expect_close = 0;
+ return 0;
+}
+
+static ssize_t nv_tco_write(struct file *file, const char __user *data,
+ size_t len, loff_t *ppos)
+{
+ /* See if we got the magic character 'V' and reload the timer */
+ if (len) {
+ if (!nowayout) {
+ size_t i;
+
+ /*
+ * note: just in case someone wrote the magic character
+ * five months ago...
+ */
+ tco_expect_close = 0;
+
+ /*
+ * scan to see whether or not we got the magic
+ * character
+ */
+ for (i = 0; i != len; i++) {
+ char c;
+ if (get_user(c, data + i))
+ return -EFAULT;
+ if (c == 'V')
+ tco_expect_close = 42;
+ }
+ }
+
+ /* someone wrote to us, we should reload the timer */
+ tco_timer_keepalive();
+ }
+ return len;
+}
+
+static long nv_tco_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ int new_options, retval = -EINVAL;
+ int new_heartbeat;
+ void __user *argp = (void __user *)arg;
+ int __user *p = argp;
+ static const struct watchdog_info ident = {
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+ .firmware_version = 0,
+ .identity = TCO_MODULE_NAME,
+ };
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
+ case WDIOC_GETSTATUS:
+ case WDIOC_GETBOOTSTATUS:
+ return put_user(0, p);
+ case WDIOC_SETOPTIONS:
+ if (get_user(new_options, p))
+ return -EFAULT;
+ if (new_options & WDIOS_DISABLECARD) {
+ tco_timer_stop();
+ retval = 0;
+ }
+ if (new_options & WDIOS_ENABLECARD) {
+ tco_timer_keepalive();
+ tco_timer_start();
+ retval = 0;
+ }
+ return retval;
+ case WDIOC_KEEPALIVE:
+ tco_timer_keepalive();
+ return 0;
+ case WDIOC_SETTIMEOUT:
+ if (get_user(new_heartbeat, p))
+ return -EFAULT;
+ if (tco_timer_set_heartbeat(new_heartbeat))
+ return -EINVAL;
+ tco_timer_keepalive();
+ fallthrough;
+ case WDIOC_GETTIMEOUT:
+ return put_user(heartbeat, p);
+ default:
+ return -ENOTTY;
+ }
+}
+
+/*
+ * Kernel Interfaces
+ */
+
+static const struct file_operations nv_tco_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .write = nv_tco_write,
+ .unlocked_ioctl = nv_tco_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .open = nv_tco_open,
+ .release = nv_tco_release,
+};
+
+static struct miscdevice nv_tco_miscdev = {
+ .minor = WATCHDOG_MINOR,
+ .name = "watchdog",
+ .fops = &nv_tco_fops,
+};
+
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE. We do not actually
+ * register a pci_driver, because someone else might one day
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id tco_pci_tbl[] = {
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP51_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP55_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP78S_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_MCP79_SMBUS,
+ PCI_ANY_ID, PCI_ANY_ID, },
+ { 0, }, /* End of list */
+};
+MODULE_DEVICE_TABLE(pci, tco_pci_tbl);
+
+/*
+ * Init & exit routines
+ */
+
+static unsigned char nv_tco_getdevice(void)
+{
+ struct pci_dev *dev = NULL;
+ u32 val;
+
+ /* Find the PCI device */
+ for_each_pci_dev(dev) {
+ if (pci_match_id(tco_pci_tbl, dev) != NULL) {
+ tco_pci = dev;
+ break;
+ }
+ }
+
+ if (!tco_pci)
+ return 0;
+
+ /* Find the base io port */
+ pci_read_config_dword(tco_pci, 0x64, &val);
+ val &= 0xffff;
+ if (val == 0x0001 || val == 0x0000) {
+ /* Something is wrong here, bar isn't setup */
+ pr_err("failed to get tcobase address\n");
+ return 0;
+ }
+ val &= 0xff00;
+ tcobase = val + 0x40;
+
+ if (!request_region(tcobase, 0x10, "NV TCO")) {
+ pr_err("I/O address 0x%04x already in use\n", tcobase);
+ return 0;
+ }
+
+ /* Set a reasonable heartbeat before we stop the timer */
+ tco_timer_set_heartbeat(30);
+
+ /*
+ * Stop the TCO before we change anything so we don't race with
+ * a zeroed timer.
+ */
+ tco_timer_keepalive();
+ tco_timer_stop();
+
+ /* Disable SMI caused by TCO */
+ if (!request_region(MCP51_SMI_EN(tcobase), 4, "NV TCO")) {
+ pr_err("I/O address 0x%04x already in use\n",
+ MCP51_SMI_EN(tcobase));
+ goto out;
+ }
+ val = inl(MCP51_SMI_EN(tcobase));
+ val &= ~MCP51_SMI_EN_TCO;
+ outl(val, MCP51_SMI_EN(tcobase));
+ val = inl(MCP51_SMI_EN(tcobase));
+ release_region(MCP51_SMI_EN(tcobase), 4);
+ if (val & MCP51_SMI_EN_TCO) {
+ pr_err("Could not disable SMI caused by TCO\n");
+ goto out;
+ }
+
+ /* Check chipset's NO_REBOOT bit */
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ val |= MCP51_SMBUS_SETUP_B_TCO_REBOOT;
+ pci_write_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, val);
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ if (!(val & MCP51_SMBUS_SETUP_B_TCO_REBOOT)) {
+ pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware\n");
+ goto out;
+ }
+
+ return 1;
+out:
+ release_region(tcobase, 0x10);
+ return 0;
+}
+
+static int nv_tco_init(struct platform_device *dev)
+{
+ int ret;
+
+ /* Check whether or not the hardware watchdog is there */
+ if (!nv_tco_getdevice())
+ return -ENODEV;
+
+ /* Check to see if last reboot was due to watchdog timeout */
+ pr_info("Watchdog reboot %sdetected\n",
+ inl(TCO_STS(tcobase)) & TCO_STS_TCO2TO_STS ? "" : "not ");
+
+ /* Clear out the old status */
+ outl(TCO_STS_RESET, TCO_STS(tcobase));
+
+ /*
+ * Check that the heartbeat value is within it's range.
+ * If not, reset to the default.
+ */
+ if (tco_timer_set_heartbeat(heartbeat)) {
+ heartbeat = WATCHDOG_HEARTBEAT;
+ tco_timer_set_heartbeat(heartbeat);
+ pr_info("heartbeat value must be 2<heartbeat<39, using %d\n",
+ heartbeat);
+ }
+
+ ret = misc_register(&nv_tco_miscdev);
+ if (ret != 0) {
+ pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+ WATCHDOG_MINOR, ret);
+ goto unreg_region;
+ }
+
+ clear_bit(0, &timer_alive);
+
+ tco_timer_stop();
+
+ pr_info("initialized (0x%04x). heartbeat=%d sec (nowayout=%d)\n",
+ tcobase, heartbeat, nowayout);
+
+ return 0;
+
+unreg_region:
+ release_region(tcobase, 0x10);
+ return ret;
+}
+
+static void nv_tco_cleanup(void)
+{
+ u32 val;
+
+ /* Stop the timer before we leave */
+ if (!nowayout)
+ tco_timer_stop();
+
+ /* Set the NO_REBOOT bit to prevent later reboots, just for sure */
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ val &= ~MCP51_SMBUS_SETUP_B_TCO_REBOOT;
+ pci_write_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, val);
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ if (val & MCP51_SMBUS_SETUP_B_TCO_REBOOT) {
+ pr_crit("Couldn't unset REBOOT bit. Machine may soon reset\n");
+ }
+
+ /* Deregister */
+ misc_deregister(&nv_tco_miscdev);
+ release_region(tcobase, 0x10);
+}
+
+static int nv_tco_remove(struct platform_device *dev)
+{
+ if (tcobase)
+ nv_tco_cleanup();
+
+ return 0;
+}
+
+static void nv_tco_shutdown(struct platform_device *dev)
+{
+ u32 val;
+
+ tco_timer_stop();
+
+ /* Some BIOSes fail the POST (once) if the NO_REBOOT flag is not
+ * unset during shutdown. */
+ pci_read_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, &val);
+ val &= ~MCP51_SMBUS_SETUP_B_TCO_REBOOT;
+ pci_write_config_dword(tco_pci, MCP51_SMBUS_SETUP_B, val);
+}
+
+static struct platform_driver nv_tco_driver = {
+ .probe = nv_tco_init,
+ .remove = nv_tco_remove,
+ .shutdown = nv_tco_shutdown,
+ .driver = {
+ .name = TCO_MODULE_NAME,
+ },
+};
+
+static int __init nv_tco_init_module(void)
+{
+ int err;
+
+ pr_info("NV TCO WatchDog Timer Driver v%s\n", TCO_VERSION);
+
+ err = platform_driver_register(&nv_tco_driver);
+ if (err)
+ return err;
+
+ nv_tco_platform_device = platform_device_register_simple(
+ TCO_MODULE_NAME, -1, NULL, 0);
+ if (IS_ERR(nv_tco_platform_device)) {
+ err = PTR_ERR(nv_tco_platform_device);
+ goto unreg_platform_driver;
+ }
+
+ return 0;
+
+unreg_platform_driver:
+ platform_driver_unregister(&nv_tco_driver);
+ return err;
+}
+
+static void __exit nv_tco_cleanup_module(void)
+{
+ platform_device_unregister(nv_tco_platform_device);
+ platform_driver_unregister(&nv_tco_driver);
+ pr_info("NV TCO Watchdog Module Unloaded\n");
+}
+
+module_init(nv_tco_init_module);
+module_exit(nv_tco_cleanup_module);
+
+MODULE_AUTHOR("Mike Waychison");
+MODULE_DESCRIPTION("TCO timer driver for NV chipsets");
+MODULE_LICENSE("GPL");