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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/aspeed_wdt.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/aspeed_wdt.c')
-rw-r--r--drivers/watchdog/aspeed_wdt.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
new file mode 100644
index 000000000..86b5331bc
--- /dev/null
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -0,0 +1,484 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2016 IBM Corporation
+ *
+ * Joel Stanley <joel@jms.id.au>
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+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) ")");
+
+struct aspeed_wdt_config {
+ u32 ext_pulse_width_mask;
+ u32 irq_shift;
+ u32 irq_mask;
+};
+
+struct aspeed_wdt {
+ struct watchdog_device wdd;
+ void __iomem *base;
+ u32 ctrl;
+ const struct aspeed_wdt_config *cfg;
+};
+
+static const struct aspeed_wdt_config ast2400_config = {
+ .ext_pulse_width_mask = 0xff,
+ .irq_shift = 0,
+ .irq_mask = 0,
+};
+
+static const struct aspeed_wdt_config ast2500_config = {
+ .ext_pulse_width_mask = 0xfffff,
+ .irq_shift = 12,
+ .irq_mask = GENMASK(31, 12),
+};
+
+static const struct aspeed_wdt_config ast2600_config = {
+ .ext_pulse_width_mask = 0xfffff,
+ .irq_shift = 0,
+ .irq_mask = GENMASK(31, 10),
+};
+
+static const struct of_device_id aspeed_wdt_of_table[] = {
+ { .compatible = "aspeed,ast2400-wdt", .data = &ast2400_config },
+ { .compatible = "aspeed,ast2500-wdt", .data = &ast2500_config },
+ { .compatible = "aspeed,ast2600-wdt", .data = &ast2600_config },
+ { },
+};
+MODULE_DEVICE_TABLE(of, aspeed_wdt_of_table);
+
+#define WDT_STATUS 0x00
+#define WDT_RELOAD_VALUE 0x04
+#define WDT_RESTART 0x08
+#define WDT_CTRL 0x0C
+#define WDT_CTRL_BOOT_SECONDARY BIT(7)
+#define WDT_CTRL_RESET_MODE_SOC (0x00 << 5)
+#define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5)
+#define WDT_CTRL_RESET_MODE_ARM_CPU (0x10 << 5)
+#define WDT_CTRL_1MHZ_CLK BIT(4)
+#define WDT_CTRL_WDT_EXT BIT(3)
+#define WDT_CTRL_WDT_INTR BIT(2)
+#define WDT_CTRL_RESET_SYSTEM BIT(1)
+#define WDT_CTRL_ENABLE BIT(0)
+#define WDT_TIMEOUT_STATUS 0x10
+#define WDT_TIMEOUT_STATUS_IRQ BIT(2)
+#define WDT_TIMEOUT_STATUS_BOOT_SECONDARY BIT(1)
+#define WDT_CLEAR_TIMEOUT_STATUS 0x14
+#define WDT_CLEAR_TIMEOUT_AND_BOOT_CODE_SELECTION BIT(0)
+
+/*
+ * WDT_RESET_WIDTH controls the characteristics of the external pulse (if
+ * enabled), specifically:
+ *
+ * * Pulse duration
+ * * Drive mode: push-pull vs open-drain
+ * * Polarity: Active high or active low
+ *
+ * Pulse duration configuration is available on both the AST2400 and AST2500,
+ * though the field changes between SoCs:
+ *
+ * AST2400: Bits 7:0
+ * AST2500: Bits 19:0
+ *
+ * This difference is captured in struct aspeed_wdt_config.
+ *
+ * The AST2500 exposes the drive mode and polarity options, but not in a
+ * regular fashion. For read purposes, bit 31 represents active high or low,
+ * and bit 30 represents push-pull or open-drain. With respect to write, magic
+ * values need to be written to the top byte to change the state of the drive
+ * mode and polarity bits. Any other value written to the top byte has no
+ * effect on the state of the drive mode or polarity bits. However, the pulse
+ * width value must be preserved (as desired) if written.
+ */
+#define WDT_RESET_WIDTH 0x18
+#define WDT_RESET_WIDTH_ACTIVE_HIGH BIT(31)
+#define WDT_ACTIVE_HIGH_MAGIC (0xA5 << 24)
+#define WDT_ACTIVE_LOW_MAGIC (0x5A << 24)
+#define WDT_RESET_WIDTH_PUSH_PULL BIT(30)
+#define WDT_PUSH_PULL_MAGIC (0xA8 << 24)
+#define WDT_OPEN_DRAIN_MAGIC (0x8A << 24)
+
+#define WDT_RESTART_MAGIC 0x4755
+
+/* 32 bits at 1MHz, in milliseconds */
+#define WDT_MAX_TIMEOUT_MS 4294967
+#define WDT_DEFAULT_TIMEOUT 30
+#define WDT_RATE_1MHZ 1000000
+
+static struct aspeed_wdt *to_aspeed_wdt(struct watchdog_device *wdd)
+{
+ return container_of(wdd, struct aspeed_wdt, wdd);
+}
+
+static void aspeed_wdt_enable(struct aspeed_wdt *wdt, int count)
+{
+ wdt->ctrl |= WDT_CTRL_ENABLE;
+
+ writel(0, wdt->base + WDT_CTRL);
+ writel(count, wdt->base + WDT_RELOAD_VALUE);
+ writel(WDT_RESTART_MAGIC, wdt->base + WDT_RESTART);
+ writel(wdt->ctrl, wdt->base + WDT_CTRL);
+}
+
+static int aspeed_wdt_start(struct watchdog_device *wdd)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+
+ aspeed_wdt_enable(wdt, wdd->timeout * WDT_RATE_1MHZ);
+
+ return 0;
+}
+
+static int aspeed_wdt_stop(struct watchdog_device *wdd)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+
+ wdt->ctrl &= ~WDT_CTRL_ENABLE;
+ writel(wdt->ctrl, wdt->base + WDT_CTRL);
+
+ return 0;
+}
+
+static int aspeed_wdt_ping(struct watchdog_device *wdd)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+
+ writel(WDT_RESTART_MAGIC, wdt->base + WDT_RESTART);
+
+ return 0;
+}
+
+static int aspeed_wdt_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+ u32 actual;
+
+ wdd->timeout = timeout;
+
+ actual = min(timeout, wdd->max_hw_heartbeat_ms / 1000);
+
+ writel(actual * WDT_RATE_1MHZ, wdt->base + WDT_RELOAD_VALUE);
+ writel(WDT_RESTART_MAGIC, wdt->base + WDT_RESTART);
+
+ return 0;
+}
+
+static int aspeed_wdt_set_pretimeout(struct watchdog_device *wdd,
+ unsigned int pretimeout)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+ u32 actual = pretimeout * WDT_RATE_1MHZ;
+ u32 s = wdt->cfg->irq_shift;
+ u32 m = wdt->cfg->irq_mask;
+
+ wdd->pretimeout = pretimeout;
+ wdt->ctrl &= ~m;
+ if (pretimeout)
+ wdt->ctrl |= ((actual << s) & m) | WDT_CTRL_WDT_INTR;
+ else
+ wdt->ctrl &= ~WDT_CTRL_WDT_INTR;
+
+ writel(wdt->ctrl, wdt->base + WDT_CTRL);
+
+ return 0;
+}
+
+static int aspeed_wdt_restart(struct watchdog_device *wdd,
+ unsigned long action, void *data)
+{
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+
+ wdt->ctrl &= ~WDT_CTRL_BOOT_SECONDARY;
+ aspeed_wdt_enable(wdt, 128 * WDT_RATE_1MHZ / 1000);
+
+ mdelay(1000);
+
+ return 0;
+}
+
+/* access_cs0 shows if cs0 is accessible, hence the reverted bit */
+static ssize_t access_cs0_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct aspeed_wdt *wdt = dev_get_drvdata(dev);
+ u32 status = readl(wdt->base + WDT_TIMEOUT_STATUS);
+
+ return sysfs_emit(buf, "%u\n",
+ !(status & WDT_TIMEOUT_STATUS_BOOT_SECONDARY));
+}
+
+static ssize_t access_cs0_store(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t size)
+{
+ struct aspeed_wdt *wdt = dev_get_drvdata(dev);
+ unsigned long val;
+
+ if (kstrtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val)
+ writel(WDT_CLEAR_TIMEOUT_AND_BOOT_CODE_SELECTION,
+ wdt->base + WDT_CLEAR_TIMEOUT_STATUS);
+
+ return size;
+}
+
+/*
+ * This attribute exists only if the system has booted from the alternate
+ * flash with 'alt-boot' option.
+ *
+ * At alternate flash the 'access_cs0' sysfs node provides:
+ * ast2400: a way to get access to the primary SPI flash chip at CS0
+ * after booting from the alternate chip at CS1.
+ * ast2500: a way to restore the normal address mapping from
+ * (CS0->CS1, CS1->CS0) to (CS0->CS0, CS1->CS1).
+ *
+ * Clearing the boot code selection and timeout counter also resets to the
+ * initial state the chip select line mapping. When the SoC is in normal
+ * mapping state (i.e. booted from CS0), clearing those bits does nothing for
+ * both versions of the SoC. For alternate boot mode (booted from CS1 due to
+ * wdt2 expiration) the behavior differs as described above.
+ *
+ * This option can be used with wdt2 (watchdog1) only.
+ */
+static DEVICE_ATTR_RW(access_cs0);
+
+static struct attribute *bswitch_attrs[] = {
+ &dev_attr_access_cs0.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(bswitch);
+
+static const struct watchdog_ops aspeed_wdt_ops = {
+ .start = aspeed_wdt_start,
+ .stop = aspeed_wdt_stop,
+ .ping = aspeed_wdt_ping,
+ .set_timeout = aspeed_wdt_set_timeout,
+ .set_pretimeout = aspeed_wdt_set_pretimeout,
+ .restart = aspeed_wdt_restart,
+ .owner = THIS_MODULE,
+};
+
+static const struct watchdog_info aspeed_wdt_info = {
+ .options = WDIOF_KEEPALIVEPING
+ | WDIOF_MAGICCLOSE
+ | WDIOF_SETTIMEOUT,
+ .identity = KBUILD_MODNAME,
+};
+
+static const struct watchdog_info aspeed_wdt_pretimeout_info = {
+ .options = WDIOF_KEEPALIVEPING
+ | WDIOF_PRETIMEOUT
+ | WDIOF_MAGICCLOSE
+ | WDIOF_SETTIMEOUT,
+ .identity = KBUILD_MODNAME,
+};
+
+static irqreturn_t aspeed_wdt_irq(int irq, void *arg)
+{
+ struct watchdog_device *wdd = arg;
+ struct aspeed_wdt *wdt = to_aspeed_wdt(wdd);
+ u32 status = readl(wdt->base + WDT_TIMEOUT_STATUS);
+
+ if (status & WDT_TIMEOUT_STATUS_IRQ)
+ watchdog_notify_pretimeout(wdd);
+
+ return IRQ_HANDLED;
+}
+
+static int aspeed_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const struct of_device_id *ofdid;
+ struct aspeed_wdt *wdt;
+ struct device_node *np;
+ const char *reset_type;
+ u32 duration;
+ u32 status;
+ int ret;
+
+ wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
+ if (!wdt)
+ return -ENOMEM;
+
+ np = dev->of_node;
+
+ ofdid = of_match_node(aspeed_wdt_of_table, np);
+ if (!ofdid)
+ return -EINVAL;
+ wdt->cfg = ofdid->data;
+
+ wdt->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(wdt->base))
+ return PTR_ERR(wdt->base);
+
+ wdt->wdd.info = &aspeed_wdt_info;
+
+ if (wdt->cfg->irq_mask) {
+ int irq = platform_get_irq_optional(pdev, 0);
+
+ if (irq > 0) {
+ ret = devm_request_irq(dev, irq, aspeed_wdt_irq,
+ IRQF_SHARED, dev_name(dev),
+ wdt);
+ if (ret)
+ return ret;
+
+ wdt->wdd.info = &aspeed_wdt_pretimeout_info;
+ }
+ }
+
+ wdt->wdd.ops = &aspeed_wdt_ops;
+ wdt->wdd.max_hw_heartbeat_ms = WDT_MAX_TIMEOUT_MS;
+ wdt->wdd.parent = dev;
+
+ wdt->wdd.timeout = WDT_DEFAULT_TIMEOUT;
+ watchdog_init_timeout(&wdt->wdd, 0, dev);
+
+ watchdog_set_nowayout(&wdt->wdd, nowayout);
+
+ /*
+ * On clock rates:
+ * - ast2400 wdt can run at PCLK, or 1MHz
+ * - ast2500 only runs at 1MHz, hard coding bit 4 to 1
+ * - ast2600 always runs at 1MHz
+ *
+ * Set the ast2400 to run at 1MHz as it simplifies the driver.
+ */
+ if (of_device_is_compatible(np, "aspeed,ast2400-wdt"))
+ wdt->ctrl = WDT_CTRL_1MHZ_CLK;
+
+ /*
+ * Control reset on a per-device basis to ensure the
+ * host is not affected by a BMC reboot
+ */
+ ret = of_property_read_string(np, "aspeed,reset-type", &reset_type);
+ if (ret) {
+ wdt->ctrl |= WDT_CTRL_RESET_MODE_SOC | WDT_CTRL_RESET_SYSTEM;
+ } else {
+ if (!strcmp(reset_type, "cpu"))
+ wdt->ctrl |= WDT_CTRL_RESET_MODE_ARM_CPU |
+ WDT_CTRL_RESET_SYSTEM;
+ else if (!strcmp(reset_type, "soc"))
+ wdt->ctrl |= WDT_CTRL_RESET_MODE_SOC |
+ WDT_CTRL_RESET_SYSTEM;
+ else if (!strcmp(reset_type, "system"))
+ wdt->ctrl |= WDT_CTRL_RESET_MODE_FULL_CHIP |
+ WDT_CTRL_RESET_SYSTEM;
+ else if (strcmp(reset_type, "none"))
+ return -EINVAL;
+ }
+ if (of_property_read_bool(np, "aspeed,external-signal"))
+ wdt->ctrl |= WDT_CTRL_WDT_EXT;
+ if (of_property_read_bool(np, "aspeed,alt-boot"))
+ wdt->ctrl |= WDT_CTRL_BOOT_SECONDARY;
+
+ if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE) {
+ /*
+ * The watchdog is running, but invoke aspeed_wdt_start() to
+ * write wdt->ctrl to WDT_CTRL to ensure the watchdog's
+ * configuration conforms to the driver's expectations.
+ * Primarily, ensure we're using the 1MHz clock source.
+ */
+ aspeed_wdt_start(&wdt->wdd);
+ set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
+ }
+
+ if ((of_device_is_compatible(np, "aspeed,ast2500-wdt")) ||
+ (of_device_is_compatible(np, "aspeed,ast2600-wdt"))) {
+ u32 reg = readl(wdt->base + WDT_RESET_WIDTH);
+
+ reg &= wdt->cfg->ext_pulse_width_mask;
+ if (of_property_read_bool(np, "aspeed,ext-active-high"))
+ reg |= WDT_ACTIVE_HIGH_MAGIC;
+ else
+ reg |= WDT_ACTIVE_LOW_MAGIC;
+
+ writel(reg, wdt->base + WDT_RESET_WIDTH);
+
+ reg &= wdt->cfg->ext_pulse_width_mask;
+ if (of_property_read_bool(np, "aspeed,ext-push-pull"))
+ reg |= WDT_PUSH_PULL_MAGIC;
+ else
+ reg |= WDT_OPEN_DRAIN_MAGIC;
+
+ writel(reg, wdt->base + WDT_RESET_WIDTH);
+ }
+
+ if (!of_property_read_u32(np, "aspeed,ext-pulse-duration", &duration)) {
+ u32 max_duration = wdt->cfg->ext_pulse_width_mask + 1;
+
+ if (duration == 0 || duration > max_duration) {
+ dev_err(dev, "Invalid pulse duration: %uus\n",
+ duration);
+ duration = max(1U, min(max_duration, duration));
+ dev_info(dev, "Pulse duration set to %uus\n",
+ duration);
+ }
+
+ /*
+ * The watchdog is always configured with a 1MHz source, so
+ * there is no need to scale the microsecond value. However we
+ * need to offset it - from the datasheet:
+ *
+ * "This register decides the asserting duration of wdt_ext and
+ * wdt_rstarm signal. The default value is 0xFF. It means the
+ * default asserting duration of wdt_ext and wdt_rstarm is
+ * 256us."
+ *
+ * This implies a value of 0 gives a 1us pulse.
+ */
+ writel(duration - 1, wdt->base + WDT_RESET_WIDTH);
+ }
+
+ status = readl(wdt->base + WDT_TIMEOUT_STATUS);
+ if (status & WDT_TIMEOUT_STATUS_BOOT_SECONDARY) {
+ wdt->wdd.bootstatus = WDIOF_CARDRESET;
+
+ if (of_device_is_compatible(np, "aspeed,ast2400-wdt") ||
+ of_device_is_compatible(np, "aspeed,ast2500-wdt"))
+ wdt->wdd.groups = bswitch_groups;
+ }
+
+ dev_set_drvdata(dev, wdt);
+
+ return devm_watchdog_register_device(dev, &wdt->wdd);
+}
+
+static struct platform_driver aspeed_watchdog_driver = {
+ .probe = aspeed_wdt_probe,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = of_match_ptr(aspeed_wdt_of_table),
+ },
+};
+
+static int __init aspeed_wdt_init(void)
+{
+ return platform_driver_register(&aspeed_watchdog_driver);
+}
+arch_initcall(aspeed_wdt_init);
+
+static void __exit aspeed_wdt_exit(void)
+{
+ platform_driver_unregister(&aspeed_watchdog_driver);
+}
+module_exit(aspeed_wdt_exit);
+
+MODULE_DESCRIPTION("Aspeed Watchdog Driver");
+MODULE_LICENSE("GPL");