xref: /optee_os/core/drivers/atmel_shdwc.c (revision 95acfb12f3e7928ad08a864db1a45f7e3fd19e0e)
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 <platform_config.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 /*
38  * @type_offset	offset of Memory Device Register
39  * @type_mask	mask of Memory Device Type in Memory Device Register
40  * @compatible	the compatible string in the device tree
41  */
42 struct ddrc_reg_config {
43 	uint32_t type_offset;
44 	uint32_t type_mask;
45 	const char *compatible;
46 };
47 
48 /*
49  * @shdwc_always_secure	Is peripheral SHDWC always secured?
50  * @ddrc		DDR controller configurations
51  */
52 struct shdwc_compat {
53 	bool shdwc_always_secure;
54 	struct ddrc_reg_config ddrc;
55 };
56 
57 static vaddr_t shdwc_base;
58 static vaddr_t mpddrc_base;
59 
atmel_shdwc_available(void)60 bool atmel_shdwc_available(void)
61 {
62 	return shdwc_base != 0;
63 }
64 
atmel_shdwc_shutdown(void)65 void __noreturn atmel_shdwc_shutdown(void)
66 {
67 	vaddr_t pmc_base = at91_pmc_get_base();
68 
69 	/*
70 	 * Mask exception before entering assembly which does not expect to be
71 	 * interrupted.
72 	 */
73 	thread_mask_exceptions(THREAD_EXCP_ALL);
74 
75 	__atmel_shdwc_shutdown(mpddrc_base, shdwc_base, pmc_base);
76 
77 	/* We are going to shutdown the CPU so we will never hit this loop */
78 	while (true)
79 		;
80 }
81 
82 static const unsigned long long sdwc_dbc_period[] = {
83 	0, 3, 32, 512, 4096, 32768,
84 };
85 
at91_shdwc_debouncer_value(uint32_t in_period_us)86 static uint32_t at91_shdwc_debouncer_value(uint32_t in_period_us)
87 {
88 	int i = 0;
89 	int max_idx = ARRAY_SIZE(sdwc_dbc_period) - 1;
90 	uint64_t period_us = 0;
91 	uint64_t max_period_us = DBC_PERIOD_US(sdwc_dbc_period[max_idx]);
92 
93 	if (in_period_us > max_period_us) {
94 		DMSG("debouncer period %"PRIu32" too big, using %"PRIu64" us",
95 		     in_period_us, max_period_us);
96 		return max_idx;
97 	}
98 
99 	for (i = max_idx - 1; i > 0; i--) {
100 		period_us = DBC_PERIOD_US(sdwc_dbc_period[i]);
101 		if (in_period_us > period_us)
102 			break;
103 	}
104 
105 	return i + 1;
106 }
107 
at91_shdwc_get_wakeup_input(const void * fdt,int np)108 static uint32_t at91_shdwc_get_wakeup_input(const void *fdt, int np)
109 {
110 	const uint32_t *prop = NULL;
111 	uint32_t wk_input_mask = 0;
112 	uint32_t wuir = 0;
113 	uint32_t wk_input = 0;
114 	int child = 0;
115 	int len = 0;
116 
117 	fdt_for_each_subnode(child, fdt, np) {
118 		prop = fdt_getprop(fdt, child, "reg", &len);
119 		if (!prop || len != sizeof(uint32_t)) {
120 			DMSG("reg property is missing for node %s",
121 			     fdt_get_name(fdt, child, NULL));
122 			continue;
123 		}
124 		wk_input = fdt32_to_cpu(*prop);
125 		wk_input_mask = BIT32(wk_input);
126 		if (!(wk_input_mask & AT91_SHDW_WKUPEN_MASK)) {
127 			DMSG("wake-up input %"PRId32" out of bounds ignore",
128 			     wk_input);
129 			continue;
130 		}
131 		wuir |= wk_input_mask;
132 
133 		if (fdt_getprop(fdt, child, "atmel,wakeup-active-high", NULL))
134 			wuir |= AT91_SHDW_WKUPT(wk_input);
135 	}
136 
137 	return wuir;
138 }
139 
at91_shdwc_dt_configure(const void * fdt,int np)140 static void at91_shdwc_dt_configure(const void *fdt, int np)
141 {
142 	const uint32_t *prop = NULL;
143 	uint32_t mode = 0;
144 	uint32_t tmp = 0;
145 	uint32_t input = 0;
146 	int len = 0;
147 
148 	prop = fdt_getprop(fdt, np, "debounce-delay-us", &len);
149 	if (prop && len == sizeof(uint32_t)) {
150 		tmp = fdt32_to_cpu(*prop);
151 		mode |= AT91_SHDW_WKUPDBC(at91_shdwc_debouncer_value(tmp));
152 	}
153 
154 	if (fdt_getprop(fdt, np, "atmel,wakeup-rtc-timer", &len))
155 		mode |= AT91_SHDW_RTCWKEN;
156 
157 	if (fdt_getprop(fdt, np, "atmel,wakeup-rtt-timer", &len))
158 		mode |= AT91_SHDW_RTTWKEN;
159 
160 	io_write32(shdwc_base + AT91_SHDW_MR, mode);
161 
162 	input = at91_shdwc_get_wakeup_input(fdt, np);
163 	io_write32(shdwc_base + AT91_SHDW_WUIR, input);
164 }
165 
atmel_shdwc_probe(const void * fdt,int node,const void * compat_data)166 static TEE_Result atmel_shdwc_probe(const void *fdt, int node,
167 				    const void *compat_data)
168 {
169 	int ddr_node = 0;
170 	size_t size = 0;
171 	uint32_t ddr = AT91_DDRSDRC_MD_LPDDR2;
172 	struct shdwc_compat *compat = (struct shdwc_compat *)compat_data;
173 
174 	/*
175 	 * Assembly code relies on the fact that there is only one CPU to avoid
176 	 * any other one to invalidate TLB/I-Cache.
177 	 */
178 	COMPILE_TIME_ASSERT(CFG_TEE_CORE_NB_CORE == 1);
179 
180 	if (fdt_get_status(fdt, node) != DT_STATUS_OK_SEC)
181 		return TEE_ERROR_BAD_PARAMETERS;
182 
183 	if (!compat->shdwc_always_secure)
184 		matrix_configure_periph_secure(AT91C_ID_SYS);
185 
186 	if (dt_map_dev(fdt, node, &shdwc_base, &size, DT_MAP_AUTO) < 0)
187 		return TEE_ERROR_GENERIC;
188 
189 	ddr_node = fdt_node_offset_by_compatible(fdt, -1,
190 						 compat->ddrc.compatible);
191 	if (ddr_node < 0)
192 		return TEE_ERROR_GENERIC;
193 
194 	if (dt_map_dev(fdt, ddr_node, &mpddrc_base, &size, DT_MAP_AUTO) < 0)
195 		return TEE_ERROR_GENERIC;
196 
197 	if (!compat->ddrc.type_mask) {
198 		ddr = io_read32(mpddrc_base + compat->ddrc.type_offset);
199 		ddr &= compat->ddrc.type_mask;
200 		if (ddr != AT91_DDRSDRC_MD_LPDDR2 &&
201 		    ddr != AT91_DDRSDRC_MD_LPDDR3)
202 			mpddrc_base = 0;
203 	} else {
204 		/*
205 		 * Set the base to 0 as the code of DRAM controller for power
206 		 * down is not implemented yet.
207 		 */
208 		mpddrc_base = 0;
209 	}
210 
211 	at91_shdwc_dt_configure(fdt, node);
212 
213 	return sam_pm_init(fdt, shdwc_base);
214 }
215 
216 static const struct shdwc_compat sama5d2_compat = {
217 	.shdwc_always_secure = false,
218 	.ddrc = {
219 		.type_offset = AT91_DDRSDRC_MDR,
220 		.type_mask = AT91_DDRSDRC_MD,
221 		.compatible = "atmel,sama5d3-ddramc",
222 	}
223 };
224 
225 static const struct shdwc_compat sama7g5_compat = {
226 	.shdwc_always_secure = true,
227 	.ddrc = {
228 		.compatible = "microchip,sama7g5-uddrc",
229 	}
230 };
231 
232 static const struct dt_device_match atmel_shdwc_match_table[] = {
233 	{
234 		.compatible = "atmel,sama5d2-shdwc",
235 		.compat_data = &sama5d2_compat
236 	},
237 	{
238 		.compatible = "microchip,sama7g5-shdwc",
239 		.compat_data = &sama7g5_compat,
240 	},
241 	{ }
242 };
243 
244 DEFINE_DT_DRIVER(atmel_shdwc_dt_driver) = {
245 	.name = "atmel_shdwc",
246 	.type = DT_DRIVER_NOTYPE,
247 	.match_table = atmel_shdwc_match_table,
248 	.probe = atmel_shdwc_probe,
249 };
250