From: Henning Schild <henning.schild@xxxxxxxxxxx>
This driver adds initial support for several devices from Siemens. It is
based on a platform driver introduced in an earlier commit.
Signed-off-by: Gerd Haeussler <gerd.haeussler.ext@xxxxxxxxxxx>
Signed-off-by: Henning Schild <henning.schild@xxxxxxxxxxx>
---
drivers/watchdog/Kconfig | 11 ++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/simatic-ipc-wdt.c | 305 +++++++++++++++++++++++++++++
3 files changed, 317 insertions(+)
create mode 100644 drivers/watchdog/simatic-ipc-wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 1fe0042a48d2..948497eb4bef 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1575,6 +1575,17 @@ config NIC7018_WDT
To compile this driver as a module, choose M here: the module will be
called nic7018_wdt.
+config SIEMENS_SIMATIC_IPC_WDT
+ tristate "Siemens Simatic IPC Watchdog"
+ depends on SIEMENS_SIMATIC_IPC
+ select WATCHDOG_CORE
+ help
+ This driver adds support for several watchdogs found in Industrial
+ PCs from Siemens.
+
+ To compile this driver as a module, choose M here: the module will be
+ called simatic-ipc-wdt.
+
# M68K Architecture
config M54xx_WATCHDOG
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index f3a6540e725e..7f5c73ec058c 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -142,6 +142,7 @@ obj-$(CONFIG_NI903X_WDT) += ni903x_wdt.o
obj-$(CONFIG_NIC7018_WDT) += nic7018_wdt.o
obj-$(CONFIG_MLX_WDT) += mlx_wdt.o
obj-$(CONFIG_KEEMBAY_WATCHDOG) += keembay_wdt.o
+obj-$(CONFIG_SIEMENS_SIMATIC_IPC_WDT) += simatic-ipc-wdt.o
# M68K Architecture
obj-$(CONFIG_M54xx_WATCHDOG) += m54xx_wdt.o
diff --git a/drivers/watchdog/simatic-ipc-wdt.c b/drivers/watchdog/simatic-ipc-wdt.c
new file mode 100644
index 000000000000..b5c8b7ceb404
--- /dev/null
+++ b/drivers/watchdog/simatic-ipc-wdt.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Siemens SIMATIC IPC driver for Watchdogs
+ *
+ * Copyright (c) Siemens AG, 2020-2021
+ *
+ * Authors:
+ * Gerd Haeussler <gerd.haeussler.ext@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/watchdog.h>
+#include <linux/ioport.h>
+#include <linux/sizes.h>
+#include <linux/io.h>
+#include <linux/platform_data/x86/simatic-ipc-base.h>
+
+#define WD_ENABLE_IOADR 0x62
+#define WD_TRIGGER_IOADR 0x66
+#define GPIO_COMMUNITY0_PORT_ID 0xaf
+#define PAD_CFG_DW0_GPP_A_23 0x4b8
+#define SAFE_EN_N_427E 0x01
+#define SAFE_EN_N_227E 0x04
+#define WD_ENABLED 0x01
+
+#define TIMEOUT_MIN 2
+#define TIMEOUT_DEF 64
+#define TIMEOUT_MAX 64
+
+#define GP_STATUS_REG_227E 0x404D /* IO PORT for SAFE_EN_N on 227E */
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0000);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static DEFINE_SPINLOCK(io_lock); /* the lock for io operations */
+static struct watchdog_device wdd;
+
+static struct resource gp_status_reg_227e_res =
+ DEFINE_RES_IO_NAMED(GP_STATUS_REG_227E, SZ_1, KBUILD_MODNAME);
+
+static struct resource io_resource =
+ DEFINE_RES_IO_NAMED(WD_ENABLE_IOADR, SZ_1,
+ KBUILD_MODNAME " WD_ENABLE_IOADR");
+
+/* the actual start will be discovered with pci, 0 is a placeholder */
+static struct resource mem_resource =
+ DEFINE_RES_MEM_NAMED(0, SZ_4, "WD_RESET_BASE_ADR");
+
+static u32 wd_timeout_table[] = {2, 4, 6, 8, 16, 32, 48, 64 };
+static void __iomem *wd_reset_base_addr;
+
+static int get_timeout_idx(u32 timeout)
+{
+ int i;
+
+ i = ARRAY_SIZE(wd_timeout_table) - 1;
+ for (; i >= 0; i--) {
+ if (timeout >= wd_timeout_table[i])
+ break;
+ }
+
+ return i;
+}
+
+static int wd_start(struct watchdog_device *wdd)
+{
+ u8 regval;
+
+ spin_lock(&io_lock);
+
+ regval = inb(WD_ENABLE_IOADR);
+ regval |= WD_ENABLED;
+ outb(regval, WD_ENABLE_IOADR);
+
+ spin_unlock(&io_lock);
+
+ return 0;
+}
+
+static int wd_stop(struct watchdog_device *wdd)
+{
+ u8 regval;
+
+ spin_lock(&io_lock);
+
+ regval = inb(WD_ENABLE_IOADR);
+ regval &= ~WD_ENABLED;
+ outb(regval, WD_ENABLE_IOADR);
+
+ spin_unlock(&io_lock);
+
+ return 0;
+}
+
+static int wd_ping(struct watchdog_device *wdd)
+{
+ inb(WD_TRIGGER_IOADR);
+ return 0;
+}
+
+static int wd_set_timeout(struct watchdog_device *wdd, unsigned int t)
+{
+ u8 regval;
+ int timeout_idx = get_timeout_idx(t);
+
+ spin_lock(&io_lock);
+
+ regval = inb(WD_ENABLE_IOADR) & 0xc7;
+ regval |= timeout_idx << 3;
+ outb(regval, WD_ENABLE_IOADR);
+
+ spin_unlock(&io_lock);
+ wdd->timeout = wd_timeout_table[timeout_idx];
+
+ return 0;
+}
+
+static const struct watchdog_info wdt_ident = {
+ .options = WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING |
+ WDIOF_SETTIMEOUT,
+ .identity = KBUILD_MODNAME,
+};
+
+static const struct watchdog_ops wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = wd_start,
+ .stop = wd_stop,
+ .ping = wd_ping,
+ .set_timeout = wd_set_timeout,
+};
+
+static void wd_set_safe_en_n(u32 wdtmode, bool safe_en_n)
+{
+ u16 resetbit;
+
+ if (wdtmode == SIMATIC_IPC_DEVICE_227E) {
+ /* enable SAFE_EN_N on GP_STATUS_REG_227E */
+ resetbit = inw(GP_STATUS_REG_227E);
+ if (safe_en_n)
+ resetbit &= ~SAFE_EN_N_227E;
+ else
+ resetbit |= SAFE_EN_N_227E;
+
+ outw(resetbit, GP_STATUS_REG_227E);
+ } else {
+ /* enable SAFE_EN_N on PCH D1600 */
+ resetbit = ioread16(wd_reset_base_addr);
+
+ if (safe_en_n)
+ resetbit &= ~SAFE_EN_N_427E;
+ else
+ resetbit |= SAFE_EN_N_427E;
+
+ iowrite16(resetbit, wd_reset_base_addr);
+ }
+}
+
+static int wd_setup(u32 wdtmode, bool safe_en_n)
+{
+ u8 regval;
+ int timeout_idx = 0;
+ bool alarm_active;
+
+ timeout_idx = get_timeout_idx(TIMEOUT_DEF);
+
+ wd_set_safe_en_n(wdtmode, safe_en_n);
+
+ /* read wd register to determine alarm state */
+ regval = inb(WD_ENABLE_IOADR);
+ if (regval & 0x80) {
+ pr_warn("Watchdog alarm active.\n");
+ regval = 0x82; /* use only macro mode, reset alarm bit */
+ alarm_active = true;
+ } else {
+ regval = 0x02; /* use only macro mode */
+ alarm_active = false;
+ }
+
+ regval |= timeout_idx << 3;
+ if (nowayout)
+ regval |= WD_ENABLED;
+
+ outb(regval, WD_ENABLE_IOADR);
+
+ return alarm_active;
+}
+
+static int simatic_ipc_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int rc = 0;
+ struct simatic_ipc_platform *plat = pdev->dev.platform_data;
+ struct resource *res;
+
+ pr_debug(KBUILD_MODNAME ":%s(#%d) WDT mode: %d\n",
+ __func__, __LINE__, plat->devmode);
+
+ switch (plat->devmode) {
+ case SIMATIC_IPC_DEVICE_227E:
+ if (!devm_request_region(dev, gp_status_reg_227e_res.start,
+ resource_size(&gp_status_reg_227e_res),
+ KBUILD_MODNAME)) {
+ dev_err(dev,
+ "Unable to register IO resource at %pR\n",
+ &gp_status_reg_227e_res);
+ return -EBUSY;
+ }
+ fallthrough;
+ case SIMATIC_IPC_DEVICE_427E:
+ wdd.info = &wdt_ident;
+ wdd.ops = &wdt_ops;
+ wdd.min_timeout = TIMEOUT_MIN;
+ wdd.max_timeout = TIMEOUT_MAX;
+ wdd.parent = NULL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (!devm_request_region(dev, io_resource.start,
+ resource_size(&io_resource),
+ io_resource.name)) {
+ dev_err(dev,
+ "Unable to register IO resource at %#x\n",
+ WD_ENABLE_IOADR);
+ return -EBUSY;
+ }
+
+ if (plat->devmode == SIMATIC_IPC_DEVICE_427E) {
+ res = &mem_resource;
+
+ /* get GPIO base from PCI */
+ res->start = simatic_ipc_get_membase0(PCI_DEVFN(0x1f, 1));
+ if (res->start == 0)
+ return -ENODEV;
+
+ /* do the final address calculation */
+ res->start = res->start + (GPIO_COMMUNITY0_PORT_ID << 16) +
+ PAD_CFG_DW0_GPP_A_23;
+ res->end += res->start;
+
+ wd_reset_base_addr = devm_ioremap_resource(dev, res);
+ if (IS_ERR(wd_reset_base_addr))
+ return -ENOMEM;
+ }
+
+ wdd.bootstatus = wd_setup(plat->devmode, true);
+ if (wdd.bootstatus)
+ pr_warn(KBUILD_MODNAME ": last reboot caused by watchdog reset\n");
+
+ watchdog_set_nowayout(&wdd, nowayout);
+ watchdog_stop_on_reboot(&wdd);
+
+ rc = devm_watchdog_register_device(dev, &wdd);
+
+ if (rc == 0)
+ pr_debug("initialized. nowayout=%d\n",
+ nowayout);
+
+ return rc;
+}
+
+static int simatic_ipc_wdt_remove(struct platform_device *pdev)
+{
+ struct simatic_ipc_platform *plat = pdev->dev.platform_data;
+
+ wd_setup(plat->devmode, false);
+ return 0;
+}
+
+static struct platform_driver wdt_driver = {
+ .probe = simatic_ipc_wdt_probe,
+ .remove = simatic_ipc_wdt_remove,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ },
+};
+
+static int __init simatic_ipc_wdt_init(void)
+{
+ return platform_driver_register(&wdt_driver);
+}
+
+static void __exit simatic_ipc_wdt_exit(void)
+{
+ platform_driver_unregister(&wdt_driver);
+}
+
+module_init(simatic_ipc_wdt_init);
+module_exit(simatic_ipc_wdt_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" KBUILD_MODNAME);
+MODULE_AUTHOR("Gerd Haeussler <gerd.haeussler.ext@xxxxxxxxxxx>");
--
2.26.2
