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platform/x86: simatic-ipc: add main driver for Siemens devices

This mainly implements detection of these devices and will allow secondary drivers to work on such machines. The identification is DMI-based with a vendor specific way to tell them apart in a reliable way. Drivers for LEDs and Watchdogs will follow to make use of that platform detection. There is also some code to allow secondary drivers to find GPIO memory, that needs to be in place because the pinctrl drivers do not come up.

Henning Schild committed 4 years ago

Commit dd123e61 parent c0518b25 files · +292 −0Browse files

Unified · Split

5 files
  1. drivers/platform/x86/Kconfig +12 −0
  2. drivers/platform/x86/Makefile +3 −0
  3. drivers/platform/x86/simatic-ipc.c +176 −0
  4. include/linux/platform_data/x86/simatic-ipc-base.h +29 −0
  5. include/linux/platform_data/x86/simatic-ipc.h +72 −0
drivers/platform/x86/Kconfig+12−0
@@ -1088,6 +1088,18 @@ config INTEL_SCU_IPC_UTIL · 1087 unmodified lines
10881088 low level access for debug work and updating the firmware. Say
10891089 N unless you will be doing this on an Intel MID platform.
10901090
1091+config SIEMENS_SIMATIC_IPC
1092+ tristate "Siemens Simatic IPC Class driver"
1093+ depends on PCI
1094+ help
1095+ This Simatic IPC class driver is the central of several drivers. It
1096+ is mainly used for system identification, after which drivers in other
1097+ classes will take care of driving specifics of those machines.
1098+ i.e. LEDs and watchdog.
1099+
1100+ To compile this driver as a module, choose M here: the module
1101+ will be called simatic-ipc.
1102+
10911103 endif # X86_PLATFORM_DEVICES
10921104
10931105 config PMC_ATOM
drivers/platform/x86/Makefile+3−0
@@ -124,3 +124,6 @@ obj-$(CONFIG_INTEL_SCU_PLATFORM) += intel_scu_pltdrv.o · 123 unmodified lines
124124 obj-$(CONFIG_INTEL_SCU_WDT) += intel_scu_wdt.o
125125 obj-$(CONFIG_INTEL_SCU_IPC_UTIL) += intel_scu_ipcutil.o
126126 obj-$(CONFIG_PMC_ATOM) += pmc_atom.o
127+
128+# Siemens Simatic Industrial PCs
129+obj-$(CONFIG_SIEMENS_SIMATIC_IPC) += simatic-ipc.o
drivers/platform/x86/simatic-ipc.c+176−0
@@ -0,0 +1,176 @@
1+// SPDX-License-Identifier: GPL-2.0
2+/*
3+ * Siemens SIMATIC IPC platform driver
4+ *
5+ * Copyright (c) Siemens AG, 2018-2021
6+ *
7+ * Authors:
8+ * Henning Schild <henning.schild@siemens.com>
9+ * Jan Kiszka <jan.kiszka@siemens.com>
10+ * Gerd Haeussler <gerd.haeussler.ext@siemens.com>
11+ */
12+
13+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14+
15+#include <linux/dmi.h>
16+#include <linux/kernel.h>
17+#include <linux/module.h>
18+#include <linux/pci.h>
19+#include <linux/platform_data/x86/simatic-ipc.h>
20+#include <linux/platform_device.h>
21+
22+static struct platform_device *ipc_led_platform_device;
23+static struct platform_device *ipc_wdt_platform_device;
24+
25+static const struct dmi_system_id simatic_ipc_whitelist[] = {
26+ {
27+ .matches = {
28+ DMI_MATCH(DMI_SYS_VENDOR, "SIEMENS AG"),
29+ },
30+ },
31+ {}
32+};
33+
34+static struct simatic_ipc_platform platform_data;
35+
36+static struct {
37+ u32 station_id;
38+ u8 led_mode;
39+ u8 wdt_mode;
40+} device_modes[] = {
41+ {SIMATIC_IPC_IPC127E, SIMATIC_IPC_DEVICE_127E, SIMATIC_IPC_DEVICE_NONE},
42+ {SIMATIC_IPC_IPC227D, SIMATIC_IPC_DEVICE_227D, SIMATIC_IPC_DEVICE_NONE},
43+ {SIMATIC_IPC_IPC227E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_227E},
44+ {SIMATIC_IPC_IPC277E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_227E},
45+ {SIMATIC_IPC_IPC427D, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_NONE},
46+ {SIMATIC_IPC_IPC427E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_427E},
47+ {SIMATIC_IPC_IPC477E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_427E},
48+};
49+
50+static int register_platform_devices(u32 station_id)
51+{
52+ u8 ledmode = SIMATIC_IPC_DEVICE_NONE;
53+ u8 wdtmode = SIMATIC_IPC_DEVICE_NONE;
54+ int i;
55+
56+ platform_data.devmode = SIMATIC_IPC_DEVICE_NONE;
57+
58+ for (i = 0; i < ARRAY_SIZE(device_modes); i++) {
59+ if (device_modes[i].station_id == station_id) {
60+ ledmode = device_modes[i].led_mode;
61+ wdtmode = device_modes[i].wdt_mode;
62+ break;
63+ }
64+ }
65+
66+ if (ledmode != SIMATIC_IPC_DEVICE_NONE) {
67+ platform_data.devmode = ledmode;
68+ ipc_led_platform_device =
69+ platform_device_register_data(NULL,
70+ KBUILD_MODNAME "_leds", PLATFORM_DEVID_NONE,
71+ &platform_data,
72+ sizeof(struct simatic_ipc_platform));
73+ if (IS_ERR(ipc_led_platform_device))
74+ return PTR_ERR(ipc_led_platform_device);
75+
76+ pr_debug("device=%s created\n",
77+ ipc_led_platform_device->name);
78+ }
79+
80+ if (wdtmode != SIMATIC_IPC_DEVICE_NONE) {
81+ platform_data.devmode = wdtmode;
82+ ipc_wdt_platform_device =
83+ platform_device_register_data(NULL,
84+ KBUILD_MODNAME "_wdt", PLATFORM_DEVID_NONE,
85+ &platform_data,
86+ sizeof(struct simatic_ipc_platform));
87+ if (IS_ERR(ipc_wdt_platform_device))
88+ return PTR_ERR(ipc_wdt_platform_device);
89+
90+ pr_debug("device=%s created\n",
91+ ipc_wdt_platform_device->name);
92+ }
93+
94+ if (ledmode == SIMATIC_IPC_DEVICE_NONE &&
95+ wdtmode == SIMATIC_IPC_DEVICE_NONE) {
96+ pr_warn("unsupported IPC detected, station id=%08x\n",
97+ station_id);
98+ return -EINVAL;
99+ }
100+
101+ return 0;
102+}
103+
104+/* FIXME: this should eventually be done with generic P2SB discovery code
105+ * the individual drivers for watchdogs and LEDs access memory that implements
106+ * GPIO, but pinctrl will not come up because of missing ACPI entries
107+ *
108+ * While there is no conflict a cleaner solution would be to somehow bring up
109+ * pinctrl even with these ACPI entries missing, and base the drivers on pinctrl.
110+ * After which the following function could be dropped, together with the code
111+ * poking the memory.
112+ */
113+/*
114+ * Get membase address from PCI, used in leds and wdt module. Here we read
115+ * the bar0. The final address calculation is done in the appropriate modules
116+ */
117+u32 simatic_ipc_get_membase0(unsigned int p2sb)
118+{
119+ struct pci_bus *bus;
120+ u32 bar0 = 0;
121+ /*
122+ * The GPIO memory is in bar0 of the hidden P2SB device.
123+ * Unhide the device to have a quick look at it, before we hide it
124+ * again.
125+ * Also grab the pci rescan lock so that device does not get discovered
126+ * and remapped while it is visible.
127+ * This code is inspired by drivers/mfd/lpc_ich.c
128+ */
129+ bus = pci_find_bus(0, 0);
130+ pci_lock_rescan_remove();
131+ pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x0);
132+ pci_bus_read_config_dword(bus, p2sb, PCI_BASE_ADDRESS_0, &bar0);
133+
134+ bar0 &= ~0xf;
135+ pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x1);
136+ pci_unlock_rescan_remove();
137+
138+ return bar0;
139+}
140+EXPORT_SYMBOL(simatic_ipc_get_membase0);
141+
142+static int __init simatic_ipc_init_module(void)
143+{
144+ const struct dmi_system_id *match;
145+ u32 station_id;
146+ int err;
147+
148+ match = dmi_first_match(simatic_ipc_whitelist);
149+ if (!match)
150+ return 0;
151+
152+ err = dmi_walk(simatic_ipc_find_dmi_entry_helper, &station_id);
153+
154+ if (err || station_id == SIMATIC_IPC_INVALID_STATION_ID) {
155+ pr_warn("DMI entry %d not found\n", SIMATIC_IPC_DMI_ENTRY_OEM);
156+ return 0;
157+ }
158+
159+ return register_platform_devices(station_id);
160+}
161+
162+static void __exit simatic_ipc_exit_module(void)
163+{
164+ platform_device_unregister(ipc_led_platform_device);
165+ ipc_led_platform_device = NULL;
166+
167+ platform_device_unregister(ipc_wdt_platform_device);
168+ ipc_wdt_platform_device = NULL;
169+}
170+
171+module_init(simatic_ipc_init_module);
172+module_exit(simatic_ipc_exit_module);
173+
174+MODULE_LICENSE("GPL v2");
175+MODULE_AUTHOR("Gerd Haeussler <gerd.haeussler.ext@siemens.com>");
176+MODULE_ALIAS("dmi:*:svnSIEMENSAG:*");
include/linux/platform_data/x86/simatic-ipc-base.h+29−0
@@ -0,0 +1,29 @@
1+/* SPDX-License-Identifier: GPL-2.0 */
2+/*
3+ * Siemens SIMATIC IPC drivers
4+ *
5+ * Copyright (c) Siemens AG, 2018-2021
6+ *
7+ * Authors:
8+ * Henning Schild <henning.schild@siemens.com>
9+ * Gerd Haeussler <gerd.haeussler.ext@siemens.com>
10+ */
11+
12+#ifndef __PLATFORM_DATA_X86_SIMATIC_IPC_BASE_H
13+#define __PLATFORM_DATA_X86_SIMATIC_IPC_BASE_H
14+
15+#include <linux/types.h>
16+
17+#define SIMATIC_IPC_DEVICE_NONE 0
18+#define SIMATIC_IPC_DEVICE_227D 1
19+#define SIMATIC_IPC_DEVICE_427E 2
20+#define SIMATIC_IPC_DEVICE_127E 3
21+#define SIMATIC_IPC_DEVICE_227E 4
22+
23+struct simatic_ipc_platform {
24+ u8 devmode;
25+};
26+
27+u32 simatic_ipc_get_membase0(unsigned int p2sb);
28+
29+#endif /* __PLATFORM_DATA_X86_SIMATIC_IPC_BASE_H */
include/linux/platform_data/x86/simatic-ipc.h+72−0
@@ -0,0 +1,72 @@
1+/* SPDX-License-Identifier: GPL-2.0 */
2+/*
3+ * Siemens SIMATIC IPC drivers
4+ *
5+ * Copyright (c) Siemens AG, 2018-2021
6+ *
7+ * Authors:
8+ * Henning Schild <henning.schild@siemens.com>
9+ * Gerd Haeussler <gerd.haeussler.ext@siemens.com>
10+ */
11+
12+#ifndef __PLATFORM_DATA_X86_SIMATIC_IPC_H
13+#define __PLATFORM_DATA_X86_SIMATIC_IPC_H
14+
15+#include <linux/dmi.h>
16+#include <linux/platform_data/x86/simatic-ipc-base.h>
17+
18+#define SIMATIC_IPC_DMI_ENTRY_OEM 129
19+/* binary type */
20+#define SIMATIC_IPC_DMI_TYPE 0xff
21+#define SIMATIC_IPC_DMI_GROUP 0x05
22+#define SIMATIC_IPC_DMI_ENTRY 0x02
23+#define SIMATIC_IPC_DMI_TID 0x02
24+
25+enum simatic_ipc_station_ids {
26+ SIMATIC_IPC_INVALID_STATION_ID = 0,
27+ SIMATIC_IPC_IPC227D = 0x00000501,
28+ SIMATIC_IPC_IPC427D = 0x00000701,
29+ SIMATIC_IPC_IPC227E = 0x00000901,
30+ SIMATIC_IPC_IPC277E = 0x00000902,
31+ SIMATIC_IPC_IPC427E = 0x00000A01,
32+ SIMATIC_IPC_IPC477E = 0x00000A02,
33+ SIMATIC_IPC_IPC127E = 0x00000D01,
34+};
35+
36+static inline u32 simatic_ipc_get_station_id(u8 *data, int max_len)
37+{
38+ struct {
39+ u8 type; /* type (0xff = binary) */
40+ u8 len; /* len of data entry */
41+ u8 group;
42+ u8 entry;
43+ u8 tid;
44+ __le32 station_id; /* station id (LE) */
45+ } __packed * data_entry = (void *)data + sizeof(struct dmi_header);
46+
47+ while ((u8 *)data_entry < data + max_len) {
48+ if (data_entry->type == SIMATIC_IPC_DMI_TYPE &&
49+ data_entry->len == sizeof(*data_entry) &&
50+ data_entry->group == SIMATIC_IPC_DMI_GROUP &&
51+ data_entry->entry == SIMATIC_IPC_DMI_ENTRY &&
52+ data_entry->tid == SIMATIC_IPC_DMI_TID) {
53+ return le32_to_cpu(data_entry->station_id);
54+ }
55+ data_entry = (void *)((u8 *)(data_entry) + data_entry->len);
56+ }
57+
58+ return SIMATIC_IPC_INVALID_STATION_ID;
59+}
60+
61+static inline void
62+simatic_ipc_find_dmi_entry_helper(const struct dmi_header *dh, void *_data)
63+{
64+ u32 *id = _data;
65+
66+ if (dh->type != SIMATIC_IPC_DMI_ENTRY_OEM)
67+ return;
68+
69+ *id = simatic_ipc_get_station_id((u8 *)dh, dh->length);
70+}
71+
72+#endif /* __PLATFORM_DATA_X86_SIMATIC_IPC_H */