1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3 * Copyright 2017-2019 NXP
4 *
5 * Peng Fan <peng.fan@nxp.com>
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright notice,
11 * this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright notice,
14 * this list of conditions and the following disclaimer in the documentation
15 * and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
21 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include <assert.h>
31 #include <drivers/imx_wdog.h>
32 #include <io.h>
33 #include <keep.h>
34 #include <kernel/dt.h>
35 #include <kernel/boot.h>
36 #include <kernel/panic.h>
37 #include <libfdt.h>
38 #include <mm/core_memprot.h>
39 #include <mm/core_mmu.h>
40 #include <util.h>
41
42 static bool ext_reset_output __maybe_unused;
43 static vaddr_t wdog_base;
44
imx_wdog_restart(bool external_reset __maybe_unused)45 void imx_wdog_restart(bool external_reset __maybe_unused)
46 {
47 uint32_t val = 0;
48
49 if (!wdog_base) {
50 EMSG("No wdog mapped\n");
51 panic();
52 }
53
54 #ifdef CFG_MX7ULP
55 val = io_read32(wdog_base + WDOG_CS);
56
57 io_write32(wdog_base + WDOG_CNT, UNLOCK);
58 /* Enable wdog */
59 io_write32(wdog_base + WDOG_CS, val | WDOG_CS_EN);
60
61 io_write32(wdog_base + WDOG_CNT, UNLOCK);
62 io_write32(wdog_base + WDOG_TOVAL, 1000);
63 io_write32(wdog_base + WDOG_CNT, REFRESH);
64 #else
65 if (external_reset && ext_reset_output)
66 val = 0x14;
67 else
68 val = 0x24;
69
70 DMSG("val %x\n", val);
71
72 io_write16(wdog_base + WDT_WCR, val);
73 dsb();
74
75 if (io_read16(wdog_base + WDT_WCR) & WDT_WCR_WDE) {
76 io_write16(wdog_base + WDT_WSR, WDT_SEQ1);
77 io_write16(wdog_base + WDT_WSR, WDT_SEQ2);
78 }
79
80 io_write16(wdog_base + WDT_WCR, val);
81 io_write16(wdog_base + WDT_WCR, val);
82 #endif
83
84 while (1)
85 ;
86 }
87 DECLARE_KEEP_PAGER(imx_wdog_restart);
88
89 #if defined(CFG_DT) && !defined(CFG_EXTERNAL_DTB_OVERLAY)
90 static const char * const dt_wdog_match_table[] = {
91 "fsl,imx21-wdt",
92 "fsl,imx7ulp-wdt",
93 };
94
imx_wdog_base(vaddr_t * wdog_vbase)95 static TEE_Result imx_wdog_base(vaddr_t *wdog_vbase)
96 {
97 const char *match = NULL;
98 void *fdt = NULL;
99 vaddr_t vbase = 0;
100 int found_off = 0;
101 size_t sz = 0;
102 int off = 0;
103 int st = 0;
104 uint32_t i = 0;
105
106 fdt = get_dt();
107 if (!fdt) {
108 EMSG("No DTB\n");
109 return TEE_ERROR_NOT_SUPPORTED;
110 }
111
112 /* search the first usable wdog */
113 for (i = 0; i < ARRAY_SIZE(dt_wdog_match_table); i++) {
114 match = dt_wdog_match_table[i];
115 off = 0;
116 while (off >= 0) {
117 off = fdt_node_offset_by_compatible(fdt, off, match);
118 if (off > 0) {
119 st = _fdt_get_status(fdt, off);
120 if (st & DT_STATUS_OK_SEC) {
121 DMSG("Wdog found at %u", off);
122 found_off = off;
123 break;
124 }
125 }
126 }
127 if (found_off)
128 break;
129 else
130 DMSG("%s not found in DTB", dt_wdog_match_table[i]);
131 }
132
133 if (!found_off) {
134 EMSG("No Watchdog found in DTB\n");
135 return TEE_ERROR_ITEM_NOT_FOUND;
136 }
137
138 ext_reset_output = dt_have_prop(fdt, found_off,
139 "fsl,ext-reset-output");
140
141 if (dt_map_dev(fdt, found_off, &vbase, &sz, DT_MAP_AUTO) < 0) {
142 EMSG("Failed to map Watchdog\n");
143 return TEE_ERROR_ITEM_NOT_FOUND;
144 }
145
146 *wdog_vbase = vbase;
147
148 return TEE_SUCCESS;
149 }
150 #else
151 register_phys_mem_pgdir(MEM_AREA_IO_SEC, WDOG_BASE, CORE_MMU_PGDIR_SIZE);
imx_wdog_base(vaddr_t * wdog_vbase)152 static TEE_Result imx_wdog_base(vaddr_t *wdog_vbase)
153 {
154 *wdog_vbase = (vaddr_t)phys_to_virt(WDOG_BASE, MEM_AREA_IO_SEC, 1);
155 #if defined(CFG_IMX_WDOG_EXT_RESET)
156 ext_reset_output = true;
157 #endif
158 return TEE_SUCCESS;
159 }
160 #endif
161
imx_wdog_init(void)162 static TEE_Result imx_wdog_init(void)
163 {
164 return imx_wdog_base(&wdog_base);
165 }
166 driver_init(imx_wdog_init);
167