xref: /openbmc/qemu/include/hw/watchdog/wdt_imx2.h (revision a68694cd)
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 typedef struct IMX2WdtState IMX2WdtState;
23 DECLARE_INSTANCE_CHECKER(IMX2WdtState, IMX2_WDT,
24                          TYPE_IMX2_WDT)
25 
26 enum IMX2WdtRegisters {
27     IMX2_WDT_WCR  = 0x0000, /* Control Register */
28     IMX2_WDT_WSR  = 0x0002, /* Service Register */
29     IMX2_WDT_WRSR = 0x0004, /* Reset Status Register */
30     IMX2_WDT_WICR = 0x0006, /* Interrupt Control Register */
31     IMX2_WDT_WMCR = 0x0008, /* Misc Register */
32 };
33 
34 #define IMX2_WDT_MMIO_SIZE 0x000a
35 
36 /* Control Register definitions */
37 #define IMX2_WDT_WCR_WT         (0xFF << 8) /* Watchdog Timeout Field */
38 #define IMX2_WDT_WCR_WDW        BIT(7)      /* WDOG Disable for Wait */
39 #define IMX2_WDT_WCR_WDA        BIT(5)      /* WDOG Assertion */
40 #define IMX2_WDT_WCR_SRS        BIT(4)      /* Software Reset Signal */
41 #define IMX2_WDT_WCR_WDT        BIT(3)      /* WDOG Timeout Assertion */
42 #define IMX2_WDT_WCR_WDE        BIT(2)      /* Watchdog Enable */
43 #define IMX2_WDT_WCR_WDBG       BIT(1)      /* Watchdog Debug Enable */
44 #define IMX2_WDT_WCR_WDZST      BIT(0)      /* Watchdog Timer Suspend */
45 
46 #define IMX2_WDT_WCR_LOCK_MASK  (IMX2_WDT_WCR_WDZST | IMX2_WDT_WCR_WDBG \
47                                  | IMX2_WDT_WCR_WDW)
48 
49 /* Service Register definitions */
50 #define IMX2_WDT_SEQ1           0x5555      /* service sequence 1 */
51 #define IMX2_WDT_SEQ2           0xAAAA      /* service sequence 2 */
52 
53 /* Reset Status Register definitions */
54 #define IMX2_WDT_WRSR_TOUT      BIT(1)      /* Reset due to Timeout */
55 #define IMX2_WDT_WRSR_SFTW      BIT(0)      /* Reset due to software reset */
56 
57 /* Interrupt Control Register definitions */
58 #define IMX2_WDT_WICR_WIE       BIT(15)     /* Interrupt Enable */
59 #define IMX2_WDT_WICR_WTIS      BIT(14)     /* Interrupt Status */
60 #define IMX2_WDT_WICR_WICT      0xff        /* Interrupt Timeout */
61 #define IMX2_WDT_WICR_WICT_DEF  0x04        /* Default interrupt timeout (2s) */
62 
63 #define IMX2_WDT_WICR_LOCK_MASK (IMX2_WDT_WICR_WIE | IMX2_WDT_WICR_WICT)
64 
65 /* Misc Control Register definitions */
66 #define IMX2_WDT_WMCR_PDE       BIT(0)      /* Power-Down Enable */
67 
68 struct IMX2WdtState {
69     /* <private> */
70     SysBusDevice parent_obj;
71 
72     /*< public >*/
73     MemoryRegion mmio;
74     qemu_irq irq;
75 
76     struct ptimer_state *timer;
77     struct ptimer_state *itimer;
78 
79     bool pretimeout_support;
80     bool wicr_locked;
81 
82     uint16_t wcr;
83     uint16_t wsr;
84     uint16_t wrsr;
85     uint16_t wicr;
86     uint16_t wmcr;
87 
88     bool wcr_locked;            /* affects WDZST, WDBG, and WDW */
89     bool wcr_wde_locked;        /* affects WDE */
90     bool wcr_wdt_locked;        /* affects WDT (never cleared) */
91 };
92 
93 #endif /* IMX2_WDT_H */
94