xref: /optee_os/core/drivers/atmel_shdwc.c (revision 9e3c57c88b0cdd41de57107725621c8c0857a838)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2015 Atmel Corporation,
4  *                    Nicolas Ferre <nicolas.ferre@atmel.com>
5  * Copyright (c) 2021, Microchip
6  */
7 
8 #include <drivers/atmel_shdwc.h>
9 #include <drivers/sam/at91_ddr.h>
10 #include <drivers/pm/sam/atmel_pm.h>
11 #include <io.h>
12 #include <kernel/dt.h>
13 #include <kernel/dt_driver.h>
14 #include <kernel/thread.h>
15 #include <libfdt.h>
16 #include <matrix.h>
17 #include <sama5d2.h>
18 #include <stdbool.h>
19 #include <tee_api_defines.h>
20 #include <tee_api_types.h>
21 #include <trace.h>
22 #include <types_ext.h>
23 #include <util.h>
24 
25 #include "at91_clk.h"
26 
27 #define SHDW_WK_PIN(reg, cfg)	((reg) & \
28 					AT91_SHDW_WKUPIS((cfg)->wkup_pin_input))
29 #define SHDW_RTCWK(reg, cfg)	(((reg) >> ((cfg)->sr_rtcwk_shift)) & 0x1)
30 #define SHDW_RTTWK(reg, cfg)	(((reg) >> ((cfg)->sr_rttwk_shift)) & 0x1)
31 #define SHDW_RTCWKEN(cfg)	BIT((cfg)->mr_rtcwk_shift)
32 #define SHDW_RTTWKEN(cfg)	BIT((cfg)->mr_rttwk_shift)
33 
34 #define SLOW_CLK_FREQ		32768ULL
35 #define DBC_PERIOD_US(x)	DIV_ROUND_UP((1000000ULL * (x)), SLOW_CLK_FREQ)
36 
37 static vaddr_t shdwc_base;
38 static vaddr_t mpddrc_base;
39 
40 bool atmel_shdwc_available(void)
41 {
42 	return shdwc_base != 0;
43 }
44 
45 void __noreturn atmel_shdwc_shutdown(void)
46 {
47 	vaddr_t pmc_base = at91_pmc_get_base();
48 
49 	/*
50 	 * Mask exception before entering assembly which does not expect to be
51 	 * interrupted.
52 	 */
53 	thread_mask_exceptions(THREAD_EXCP_ALL);
54 
55 	__atmel_shdwc_shutdown(mpddrc_base, shdwc_base, pmc_base);
56 
57 	/* We are going to shutdown the CPU so we will never hit this loop */
58 	while (true)
59 		;
60 }
61 
62 static const unsigned long long sdwc_dbc_period[] = {
63 	0, 3, 32, 512, 4096, 32768,
64 };
65 
66 static uint32_t at91_shdwc_debouncer_value(uint32_t in_period_us)
67 {
68 	int i = 0;
69 	int max_idx = ARRAY_SIZE(sdwc_dbc_period) - 1;
70 	uint64_t period_us = 0;
71 	uint64_t max_period_us = DBC_PERIOD_US(sdwc_dbc_period[max_idx]);
72 
73 	if (in_period_us > max_period_us) {
74 		DMSG("debouncer period %"PRIu32" too big, using %"PRIu64" us",
75 		     in_period_us, max_period_us);
76 		return max_idx;
77 	}
78 
79 	for (i = max_idx - 1; i > 0; i--) {
80 		period_us = DBC_PERIOD_US(sdwc_dbc_period[i]);
81 		if (in_period_us > period_us)
82 			break;
83 	}
84 
85 	return i + 1;
86 }
87 
88 static uint32_t at91_shdwc_get_wakeup_input(const void *fdt, int np)
89 {
90 	const uint32_t *prop = NULL;
91 	uint32_t wk_input_mask = 0;
92 	uint32_t wuir = 0;
93 	uint32_t wk_input = 0;
94 	int child = 0;
95 	int len = 0;
96 
97 	fdt_for_each_subnode(child, fdt, np) {
98 		prop = fdt_getprop(fdt, child, "reg", &len);
99 		if (!prop || len != sizeof(uint32_t)) {
100 			DMSG("reg property is missing for node %s",
101 			     fdt_get_name(fdt, child, NULL));
102 			continue;
103 		}
104 		wk_input = fdt32_to_cpu(*prop);
105 		wk_input_mask = BIT32(wk_input);
106 		if (!(wk_input_mask & AT91_SHDW_WKUPEN_MASK)) {
107 			DMSG("wake-up input %"PRId32" out of bounds ignore",
108 			     wk_input);
109 			continue;
110 		}
111 		wuir |= wk_input_mask;
112 
113 		if (fdt_getprop(fdt, child, "atmel,wakeup-active-high", NULL))
114 			wuir |= AT91_SHDW_WKUPT(wk_input);
115 	}
116 
117 	return wuir;
118 }
119 
120 static void at91_shdwc_dt_configure(const void *fdt, int np)
121 {
122 	const uint32_t *prop = NULL;
123 	uint32_t mode = 0;
124 	uint32_t tmp = 0;
125 	uint32_t input = 0;
126 	int len = 0;
127 
128 	prop = fdt_getprop(fdt, np, "debounce-delay-us", &len);
129 	if (prop && len == sizeof(uint32_t)) {
130 		tmp = fdt32_to_cpu(*prop);
131 		mode |= AT91_SHDW_WKUPDBC(at91_shdwc_debouncer_value(tmp));
132 	}
133 
134 	if (fdt_getprop(fdt, np, "atmel,wakeup-rtc-timer", &len))
135 		mode |= AT91_SHDW_RTCWKEN;
136 
137 	io_write32(shdwc_base + AT91_SHDW_MR, mode);
138 
139 	input = at91_shdwc_get_wakeup_input(fdt, np);
140 	io_write32(shdwc_base + AT91_SHDW_WUIR, input);
141 }
142 
143 static TEE_Result atmel_shdwc_probe(const void *fdt, int node,
144 				    const void *compat_data __unused)
145 {
146 	int ddr_node = 0;
147 	size_t size = 0;
148 	uint32_t ddr = AT91_DDRSDRC_MD_LPDDR2;
149 
150 	/*
151 	 * Assembly code relies on the fact that there is only one CPU to avoid
152 	 * any other one to invalidate TLB/I-Cache.
153 	 */
154 	COMPILE_TIME_ASSERT(CFG_TEE_CORE_NB_CORE == 1);
155 
156 	if (fdt_get_status(fdt, node) != DT_STATUS_OK_SEC)
157 		return TEE_ERROR_BAD_PARAMETERS;
158 
159 	matrix_configure_periph_secure(AT91C_ID_SYS);
160 
161 	if (dt_map_dev(fdt, node, &shdwc_base, &size, DT_MAP_AUTO) < 0)
162 		return TEE_ERROR_GENERIC;
163 
164 	ddr_node = fdt_node_offset_by_compatible(fdt, -1,
165 						 "atmel,sama5d3-ddramc");
166 	if (ddr_node < 0)
167 		return TEE_ERROR_GENERIC;
168 
169 	if (dt_map_dev(fdt, ddr_node, &mpddrc_base, &size, DT_MAP_AUTO) < 0)
170 		return TEE_ERROR_GENERIC;
171 
172 	ddr = io_read32(mpddrc_base + AT91_DDRSDRC_MDR) & AT91_DDRSDRC_MD;
173 	if (ddr != AT91_DDRSDRC_MD_LPDDR2 && ddr != AT91_DDRSDRC_MD_LPDDR3)
174 		mpddrc_base = 0;
175 
176 	at91_shdwc_dt_configure(fdt, node);
177 
178 	return sama5d2_pm_init(fdt, shdwc_base);
179 }
180 
181 static const struct dt_device_match atmel_shdwc_match_table[] = {
182 	{ .compatible = "atmel,sama5d2-shdwc" },
183 	{ }
184 };
185 
186 DEFINE_DT_DRIVER(atmel_shdwc_dt_driver) = {
187 	.name = "atmel_shdwc",
188 	.type = DT_DRIVER_NOTYPE,
189 	.match_table = atmel_shdwc_match_table,
190 	.probe = atmel_shdwc_probe,
191 };
192