xref: /openbmc/qemu/include/hw/watchdog/wdt_imx2.h (revision b91a0fa7)
1 /*
2  * Copyright (c) 2017, Impinj, Inc.
3  *
4  * i.MX2 Watchdog IP block
5  *
6  * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or later.
9  * See the COPYING file in the top-level directory.
10  */
11 
12 #ifndef IMX2_WDT_H
13 #define IMX2_WDT_H
14 
15 #include "qemu/bitops.h"
16 #include "hw/sysbus.h"
17 #include "hw/irq.h"
18 #include "hw/ptimer.h"
19 #include "qom/object.h"
20 
21 #define TYPE_IMX2_WDT "imx2.wdt"
22 OBJECT_DECLARE_SIMPLE_TYPE(IMX2WdtState, IMX2_WDT)
23 
24 enum IMX2WdtRegisters {
25     IMX2_WDT_WCR  = 0x0000, /* Control Register */
26     IMX2_WDT_WSR  = 0x0002, /* Service Register */
27     IMX2_WDT_WRSR = 0x0004, /* Reset Status Register */
28     IMX2_WDT_WICR = 0x0006, /* Interrupt Control Register */
29     IMX2_WDT_WMCR = 0x0008, /* Misc Register */
30 };
31 
32 #define IMX2_WDT_MMIO_SIZE 0x000a
33 
34 /* Control Register definitions */
35 #define IMX2_WDT_WCR_WT         (0xFF << 8) /* Watchdog Timeout Field */
36 #define IMX2_WDT_WCR_WDW        BIT(7)      /* WDOG Disable for Wait */
37 #define IMX2_WDT_WCR_WDA        BIT(5)      /* WDOG Assertion */
38 #define IMX2_WDT_WCR_SRS        BIT(4)      /* Software Reset Signal */
39 #define IMX2_WDT_WCR_WDT        BIT(3)      /* WDOG Timeout Assertion */
40 #define IMX2_WDT_WCR_WDE        BIT(2)      /* Watchdog Enable */
41 #define IMX2_WDT_WCR_WDBG       BIT(1)      /* Watchdog Debug Enable */
42 #define IMX2_WDT_WCR_WDZST      BIT(0)      /* Watchdog Timer Suspend */
43 
44 #define IMX2_WDT_WCR_LOCK_MASK  (IMX2_WDT_WCR_WDZST | IMX2_WDT_WCR_WDBG \
45                                  | IMX2_WDT_WCR_WDW)
46 
47 /* Service Register definitions */
48 #define IMX2_WDT_SEQ1           0x5555      /* service sequence 1 */
49 #define IMX2_WDT_SEQ2           0xAAAA      /* service sequence 2 */
50 
51 /* Reset Status Register definitions */
52 #define IMX2_WDT_WRSR_TOUT      BIT(1)      /* Reset due to Timeout */
53 #define IMX2_WDT_WRSR_SFTW      BIT(0)      /* Reset due to software reset */
54 
55 /* Interrupt Control Register definitions */
56 #define IMX2_WDT_WICR_WIE       BIT(15)     /* Interrupt Enable */
57 #define IMX2_WDT_WICR_WTIS      BIT(14)     /* Interrupt Status */
58 #define IMX2_WDT_WICR_WICT      0xff        /* Interrupt Timeout */
59 #define IMX2_WDT_WICR_WICT_DEF  0x04        /* Default interrupt timeout (2s) */
60 
61 #define IMX2_WDT_WICR_LOCK_MASK (IMX2_WDT_WICR_WIE | IMX2_WDT_WICR_WICT)
62 
63 /* Misc Control Register definitions */
64 #define IMX2_WDT_WMCR_PDE       BIT(0)      /* Power-Down Enable */
65 
66 struct IMX2WdtState {
67     /* <private> */
68     SysBusDevice parent_obj;
69 
70     /*< public >*/
71     MemoryRegion mmio;
72     qemu_irq irq;
73 
74     struct ptimer_state *timer;
75     struct ptimer_state *itimer;
76 
77     bool pretimeout_support;
78     bool wicr_locked;
79 
80     uint16_t wcr;
81     uint16_t wsr;
82     uint16_t wrsr;
83     uint16_t wicr;
84     uint16_t wmcr;
85 
86     bool wcr_locked;            /* affects WDZST, WDBG, and WDW */
87     bool wcr_wde_locked;        /* affects WDE */
88     bool wcr_wdt_locked;        /* affects WDT (never cleared) */
89 };
90 
91 #endif /* IMX2_WDT_H */
92