xref: /optee_os/core/drivers/atmel_saic.c (revision 71785645fa6ce42db40dbf5a54e0eaedc4f61591)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2021, Microchip
4  */
5 
6 #include <assert.h>
7 #include <drivers/atmel_saic.h>
8 #include <dt-bindings/interrupt-controller/irq.h>
9 #include <io.h>
10 #include <kernel/boot.h>
11 #include <kernel/dt.h>
12 #include <kernel/interrupt.h>
13 #include <kernel/pm.h>
14 #include <libfdt.h>
15 #include <sam_sfr.h>
16 #include <tee_api_types.h>
17 #include <trace.h>
18 
19 #define AT91_AIC_MAX_PRIO	8
20 
21 #define SAMA5D2_AIC_MAX_IRQS	77
22 
23 #define SAMA5D2_AIC_MAX_IRQS32	((SAMA5D2_AIC_MAX_IRQS + 31) / 32)
24 
25 struct saic_data {
26 	struct itr_chip chip;
27 	vaddr_t base;
28 	size_t nr_irqs;
29 	uint32_t external[SAMA5D2_AIC_MAX_IRQS32];
30 };
31 
32 static struct saic_data saic;
33 
34 static void saic_register_pm(void);
35 
36 static void saic_write_reg(uint32_t reg, uint32_t val)
37 {
38 	io_write32(saic.base + reg, val);
39 }
40 
41 static uint32_t saic_read_reg(uint32_t reg)
42 {
43 	return io_read32(saic.base + reg);
44 }
45 
46 void interrupt_main_handler(void)
47 {
48 	uint32_t irqnr = saic_read_reg(AT91_AIC_IVR);
49 
50 	interrupt_call_handlers(&saic.chip, irqnr);
51 	saic_write_reg(AT91_AIC_EOICR, 0);
52 }
53 
54 static void saic_select_it(size_t it)
55 {
56 	assert(!(it & ~AT91_AIC_SSR_ITSEL_MASK));
57 
58 	saic_write_reg(AT91_AIC_SSR, it);
59 }
60 
61 static void saic_configure_it(size_t it, uint32_t src_type, uint32_t priority)
62 {
63 	saic_select_it(it);
64 	saic_write_reg(AT91_AIC_SMR, src_type | priority);
65 }
66 
67 static bool is_external_it(size_t it)
68 {
69 	uint32_t it_grp = it / 32;
70 	uint32_t it_off = it % 32;
71 
72 	if (it >= saic.nr_irqs)
73 		panic();
74 
75 	return saic.external[it_grp] & BIT32(it_off);
76 }
77 
78 static TEE_Result saic_get_src_type(uint32_t dt_level, size_t it,
79 				    uint32_t *src_type)
80 {
81 	switch (dt_level) {
82 	case IRQ_TYPE_EDGE_RISING:
83 		*src_type = AT91_AIC_SMR_POS_EDGE;
84 		break;
85 	case IRQ_TYPE_EDGE_FALLING:
86 		if (!is_external_it(it))
87 			return TEE_ERROR_BAD_PARAMETERS;
88 
89 		*src_type = AT91_AIC_SMR_NEG_EDGE;
90 		break;
91 	case IRQ_TYPE_LEVEL_HIGH:
92 		*src_type = AT91_AIC_SMR_HIGH_LEVEL;
93 		break;
94 	case IRQ_TYPE_LEVEL_LOW:
95 		if (!is_external_it(it))
96 			return TEE_ERROR_BAD_PARAMETERS;
97 
98 		*src_type = AT91_AIC_SMR_LEVEL;
99 		break;
100 	default:
101 		return TEE_ERROR_BAD_PARAMETERS;
102 	}
103 
104 	return TEE_SUCCESS;
105 }
106 
107 static void saic_configure(struct itr_chip *chip __unused, size_t it,
108 			   uint32_t type, uint32_t prio)
109 {
110 	uint32_t src_type = AT91_AIC_SMR_HIGH_LEVEL;
111 
112 	if (it >= saic.nr_irqs)
113 		panic();
114 
115 	if (saic_get_src_type(type, it, &src_type))
116 		panic("Invalid interrupt specifier");
117 
118 	saic_configure_it(it, src_type, prio);
119 }
120 
121 static void saic_enable(struct itr_chip *chip __unused, size_t it)
122 {
123 	saic_select_it(it);
124 	saic_write_reg(AT91_AIC_IECR, 1);
125 }
126 
127 static void saic_disable(struct itr_chip *chip __unused, size_t it)
128 {
129 	saic_select_it(it);
130 	saic_write_reg(AT91_AIC_IDCR, 1);
131 }
132 
133 static const struct itr_ops saic_ops = {
134 	.configure = saic_configure,
135 	.mask = saic_disable,
136 	.unmask = saic_enable,
137 	.enable = saic_enable,
138 	.disable = saic_disable,
139 };
140 
141 static int saic_dt_get_irq(const uint32_t *properties, int len,
142 			   uint32_t *type, uint32_t *prio)
143 {
144 	int it = DT_INFO_INVALID_INTERRUPT;
145 	uint32_t src_type = 0;
146 	uint32_t priority = 0;
147 	uint32_t irq_type = 0;
148 
149 	if (len != 3)
150 		return DT_INFO_INVALID_INTERRUPT;
151 
152 	it = fdt32_to_cpu(properties[0]);
153 	if (it >= (int)saic.nr_irqs)
154 		return DT_INFO_INVALID_INTERRUPT;
155 
156 	irq_type = fdt32_to_cpu(properties[1]);
157 	if (saic_get_src_type(irq_type, it, &src_type))
158 		return DT_INFO_INVALID_INTERRUPT;
159 
160 	priority = fdt32_to_cpu(properties[2]);
161 	if (priority >= AT91_AIC_MAX_PRIO)
162 		return DT_INFO_INVALID_INTERRUPT;
163 
164 	if (type)
165 		*type = irq_type;
166 
167 	if (prio)
168 		*prio = priority;
169 
170 	return it;
171 }
172 
173 static struct saic_data saic = {
174 	.chip = {
175 		.ops = &saic_ops,
176 		.dt_get_irq = &saic_dt_get_irq,
177 	},
178 };
179 
180 static void saic_clear_aicredir(void)
181 {
182 	vaddr_t sfr_base = sam_sfr_base();
183 	uint32_t aicredir_val = 0;
184 
185 	aicredir_val = io_read32(sfr_base + AT91_SFR_SN1);
186 	aicredir_val ^= AT91_SFR_AICREDIR_XOR_KEY;
187 	aicredir_val &= AT91_SFR_AICREDIR_KEY_MASK;
188 
189 	/*
190 	 * We explicitly don't want to redirect secure interrupts to non secure
191 	 * AIC. By default, AT91Bootstrap does so on some platforms.
192 	 */
193 	io_write32(sfr_base + AT91_SFR_AICREDIR, aicredir_val);
194 }
195 
196 static void saic_init_external(const void *fdt, int node)
197 {
198 	int i = 0;
199 	int len = 0;
200 	int it_grp = 0;
201 	int it_off = 0;
202 	size_t it = 0;
203 	const uint32_t *external = NULL;
204 
205 	external = fdt_getprop(fdt, node, "atmel,external-irqs", &len);
206 	if (!external)
207 		return;
208 
209 	len /= sizeof(uint32_t);
210 	for (i = 0; i < len; i++) {
211 		it = fdt32_to_cpu(external[i]);
212 
213 		DMSG("IRQ %zu is external", it);
214 
215 		if (it >= saic.nr_irqs)
216 			panic();
217 
218 		it_grp = it / 32;
219 		it_off = it % 32;
220 
221 		saic.external[it_grp] |= BIT32(it_off);
222 	}
223 }
224 
225 static void saic_init_hw(void)
226 {
227 	unsigned int i = 0;
228 
229 	saic_clear_aicredir();
230 
231 	/* Disable write protect if any */
232 	saic_write_reg(AT91_AIC_WPMR, AT91_AIC_WPKEY);
233 
234 	/* Pop the (potential) interrupt stack (8 priority) */
235 	for (i = 0; i < 8; i++)
236 		saic_write_reg(AT91_AIC_EOICR, 0);
237 
238 	/* Disable and clear all interrupts initially */
239 	for (i = 0; i < saic.nr_irqs; i++) {
240 		saic_write_reg(AT91_AIC_IDCR, 1);
241 		saic_write_reg(AT91_AIC_ICCR, 1);
242 		/* Set interrupt vector to hold interrupt number */
243 		saic_select_it(i);
244 		saic_write_reg(AT91_AIC_SVR, i);
245 	}
246 
247 	saic_write_reg(AT91_AIC_SPU, 0xffffffff);
248 
249 	/* Disable AIC debugging */
250 	saic_write_reg(AT91_AIC_DCR, 0);
251 }
252 
253 TEE_Result atmel_saic_setup(void)
254 {
255 	int node = -1;
256 	int ret = 0;
257 	size_t size = 0;
258 	const void *fdt = get_embedded_dt();
259 
260 	/* There is only 1 SAIC controller */
261 	if (saic.base)
262 		return TEE_ERROR_GENERIC;
263 
264 	node = fdt_node_offset_by_compatible(fdt, -1, "atmel,sama5d2-saic");
265 	if (node < 0)
266 		return TEE_ERROR_GENERIC;
267 
268 	ret = dt_map_dev(fdt, node, &saic.base, &size, DT_MAP_AUTO);
269 	if (ret) {
270 		EMSG("Failed to map SAIC");
271 		return TEE_ERROR_GENERIC;
272 	}
273 
274 	saic.chip.ops = &saic_ops;
275 	saic.nr_irqs = SAMA5D2_AIC_MAX_IRQS;
276 
277 	saic_init_external(fdt, node);
278 	saic_init_hw();
279 
280 	interrupt_main_init(&saic.chip);
281 	saic_register_pm();
282 
283 	return TEE_SUCCESS;
284 }
285 
286 #ifdef CFG_PM_ARM32
287 
288 static struct {
289 	uint8_t smr[SAMA5D2_AIC_MAX_IRQS];
290 } saic_state;
291 
292 static void saic_resume(void)
293 {
294 	uint8_t it = 0;
295 
296 	saic_init_hw();
297 
298 	for (it = 0; it < SAMA5D2_AIC_MAX_IRQS; it++) {
299 		saic_select_it(it);
300 		saic_write_reg(AT91_AIC_SMR, saic_state.smr[it]);
301 	}
302 }
303 
304 static void saic_suspend(void)
305 {
306 	uint8_t it = 0;
307 
308 	for (it = 0; it < SAMA5D2_AIC_MAX_IRQS; it++) {
309 		saic_select_it(it);
310 		saic_state.smr[it] = saic_read_reg(AT91_AIC_SMR);
311 	}
312 }
313 
314 static TEE_Result saic_pm(enum pm_op op, uint32_t pm_hint __unused,
315 			  const struct pm_callback_handle *hdl __unused)
316 {
317 	switch (op) {
318 	case PM_OP_RESUME:
319 		saic_resume();
320 		break;
321 	case PM_OP_SUSPEND:
322 		saic_suspend();
323 		break;
324 	default:
325 		panic("Invalid PM operation");
326 	}
327 
328 	return TEE_SUCCESS;
329 }
330 
331 static void saic_register_pm(void)
332 {
333 	register_pm_core_service_cb(saic_pm, NULL, "saic");
334 }
335 #else
336 static void saic_register_pm(void)
337 {
338 }
339 #endif
340