xref: /rk3399_ARM-atf/drivers/st/ddr/stm32mp1_ram.c (revision 6e6ab282f70f233eb426fd93f243d8ca6922d4cc)
1 /*
2  * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
3  *
4  * SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
5  */
6 
7 #include <errno.h>
8 
9 #include <libfdt.h>
10 
11 #include <platform_def.h>
12 
13 #include <arch_helpers.h>
14 #include <common/debug.h>
15 #include <drivers/st/stm32mp1_clk.h>
16 #include <drivers/st/stm32mp1_ddr.h>
17 #include <drivers/st/stm32mp1_ddr_helpers.h>
18 #include <drivers/st/stm32mp1_ram.h>
19 #include <drivers/st/stm32mp1_rcc.h>
20 #include <dt-bindings/clock/stm32mp1-clks.h>
21 #include <lib/mmio.h>
22 
23 #define DDR_PATTERN	0xAAAAAAAAU
24 #define DDR_ANTIPATTERN	0x55555555U
25 
26 static struct ddr_info ddr_priv_data;
27 
28 int stm32mp1_ddr_clk_enable(struct ddr_info *priv, uint16_t mem_speed)
29 {
30 	unsigned long ddrphy_clk, ddr_clk, mem_speed_hz;
31 
32 	ddr_enable_clock();
33 
34 	ddrphy_clk = stm32mp1_clk_get_rate(DDRPHYC);
35 
36 	VERBOSE("DDR: mem_speed (%d MHz), RCC %ld MHz\n",
37 		mem_speed, ddrphy_clk / 1000U / 1000U);
38 
39 	mem_speed_hz = (uint32_t)mem_speed * 1000U * 1000U;
40 
41 	/* Max 10% frequency delta */
42 	if (ddrphy_clk > mem_speed_hz) {
43 		ddr_clk = ddrphy_clk - mem_speed_hz;
44 	} else {
45 		ddr_clk = mem_speed_hz - ddrphy_clk;
46 	}
47 	if (ddr_clk > mem_speed_hz) {
48 		ERROR("DDR expected freq %d MHz, current is %ld MHz\n",
49 		      mem_speed, ddrphy_clk / 1000U / 1000U);
50 		return -1;
51 	}
52 	return 0;
53 }
54 
55 /*******************************************************************************
56  * This function tests the DDR data bus wiring.
57  * This is inspired from the Data Bus Test algorithm written by Michael Barr
58  * in "Programming Embedded Systems in C and C++" book.
59  * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
60  * File: memtest.c - This source code belongs to Public Domain.
61  * Returns 0 if success, and address value else.
62  ******************************************************************************/
63 static uint32_t ddr_test_data_bus(void)
64 {
65 	uint32_t pattern;
66 
67 	for (pattern = 1U; pattern != 0U; pattern <<= 1) {
68 		mmio_write_32(STM32MP1_DDR_BASE, pattern);
69 
70 		if (mmio_read_32(STM32MP1_DDR_BASE) != pattern) {
71 			return (uint32_t)STM32MP1_DDR_BASE;
72 		}
73 	}
74 
75 	return 0;
76 }
77 
78 /*******************************************************************************
79  * This function tests the DDR address bus wiring.
80  * This is inspired from the Data Bus Test algorithm written by Michael Barr
81  * in "Programming Embedded Systems in C and C++" book.
82  * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
83  * File: memtest.c - This source code belongs to Public Domain.
84  * Returns 0 if success, and address value else.
85  ******************************************************************************/
86 static uint32_t ddr_test_addr_bus(void)
87 {
88 	uint64_t addressmask = (ddr_priv_data.info.size - 1U);
89 	uint64_t offset;
90 	uint64_t testoffset = 0;
91 
92 	/* Write the default pattern at each of the power-of-two offsets. */
93 	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
94 	     offset <<= 1) {
95 		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)offset,
96 			      DDR_PATTERN);
97 	}
98 
99 	/* Check for address bits stuck high. */
100 	mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
101 		      DDR_ANTIPATTERN);
102 
103 	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
104 	     offset <<= 1) {
105 		if (mmio_read_32(STM32MP1_DDR_BASE + (uint32_t)offset) !=
106 		    DDR_PATTERN) {
107 			return (uint32_t)(STM32MP1_DDR_BASE + offset);
108 		}
109 	}
110 
111 	mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN);
112 
113 	/* Check for address bits stuck low or shorted. */
114 	for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U;
115 	     testoffset <<= 1) {
116 		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
117 			      DDR_ANTIPATTERN);
118 
119 		if (mmio_read_32(STM32MP1_DDR_BASE) != DDR_PATTERN) {
120 			return STM32MP1_DDR_BASE;
121 		}
122 
123 		for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
124 		     offset <<= 1) {
125 			if ((mmio_read_32(STM32MP1_DDR_BASE +
126 					  (uint32_t)offset) != DDR_PATTERN) &&
127 			    (offset != testoffset)) {
128 				return (uint32_t)(STM32MP1_DDR_BASE + offset);
129 			}
130 		}
131 
132 		mmio_write_32(STM32MP1_DDR_BASE + (uint32_t)testoffset,
133 			      DDR_PATTERN);
134 	}
135 
136 	return 0;
137 }
138 
139 /*******************************************************************************
140  * This function checks the DDR size. It has to be run with Data Cache off.
141  * This test is run before data have been put in DDR, and is only done for
142  * cold boot. The DDR data can then be overwritten, and it is not useful to
143  * restore its content.
144  * Returns DDR computed size.
145  ******************************************************************************/
146 static uint32_t ddr_check_size(void)
147 {
148 	uint32_t offset = sizeof(uint32_t);
149 
150 	mmio_write_32(STM32MP1_DDR_BASE, DDR_PATTERN);
151 
152 	while (offset < STM32MP1_DDR_MAX_SIZE) {
153 		mmio_write_32(STM32MP1_DDR_BASE + offset, DDR_ANTIPATTERN);
154 		dsb();
155 
156 		if (mmio_read_32(STM32MP1_DDR_BASE) != DDR_PATTERN) {
157 			break;
158 		}
159 
160 		offset <<= 1;
161 	}
162 
163 	INFO("Memory size = 0x%x (%d MB)\n", offset, offset / (1024U * 1024U));
164 
165 	return offset;
166 }
167 
168 static int stm32mp1_ddr_setup(void)
169 {
170 	struct ddr_info *priv = &ddr_priv_data;
171 	int ret;
172 	struct stm32mp1_ddr_config config;
173 	int node, len;
174 	uint32_t tamp_clk_off = 0, uret, idx;
175 	void *fdt;
176 
177 #define PARAM(x, y)							\
178 	{								\
179 		.name = x,						\
180 		.offset = offsetof(struct stm32mp1_ddr_config, y),	\
181 		.size = sizeof(config.y) / sizeof(uint32_t)		\
182 	}
183 
184 #define CTL_PARAM(x) PARAM("st,ctl-"#x, c_##x)
185 #define PHY_PARAM(x) PARAM("st,phy-"#x, p_##x)
186 
187 	const struct {
188 		const char *name; /* Name in DT */
189 		const uint32_t offset; /* Offset in config struct */
190 		const uint32_t size;   /* Size of parameters */
191 	} param[] = {
192 		CTL_PARAM(reg),
193 		CTL_PARAM(timing),
194 		CTL_PARAM(map),
195 		CTL_PARAM(perf),
196 		PHY_PARAM(reg),
197 		PHY_PARAM(timing),
198 		PHY_PARAM(cal)
199 	};
200 
201 	if (fdt_get_address(&fdt) == 0) {
202 		return -ENOENT;
203 	}
204 
205 	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
206 	if (node < 0) {
207 		ERROR("%s: Cannot read DDR node in DT\n", __func__);
208 		return -EINVAL;
209 	}
210 
211 	config.info.speed =
212 		(uint16_t)fdt_read_uint32_default(node, "st,mem-speed",
213 						  STM32MP1_DDR_SPEED_DFLT);
214 	config.info.size = fdt_read_uint32_default(node, "st,mem-size",
215 						   STM32MP1_DDR_SIZE_DFLT);
216 	config.info.name = fdt_getprop(fdt, node, "st,mem-name", &len);
217 	if (config.info.name == NULL) {
218 		VERBOSE("%s: no st,mem-name\n", __func__);
219 		return -EINVAL;
220 	}
221 	INFO("RAM: %s\n", config.info.name);
222 
223 	for (idx = 0; idx < ARRAY_SIZE(param); idx++) {
224 		ret = fdt_read_uint32_array(node, param[idx].name,
225 					    (void *)((uint32_t)&config +
226 						     param[idx].offset),
227 					    param[idx].size);
228 
229 		VERBOSE("%s: %s[0x%x] = %d\n", __func__,
230 			param[idx].name, param[idx].size, ret);
231 		if (ret != 0) {
232 			ERROR("%s: Cannot read %s\n",
233 			      __func__, param[idx].name);
234 			return -EINVAL;
235 		}
236 	}
237 
238 	if (!stm32mp1_clk_is_enabled(RTCAPB)) {
239 		tamp_clk_off = 1;
240 		if (stm32mp1_clk_enable(RTCAPB) != 0) {
241 			return -EINVAL;
242 		}
243 	}
244 
245 	if (tamp_clk_off != 0U) {
246 		if (stm32mp1_clk_disable(RTCAPB) != 0) {
247 			return -EINVAL;
248 		}
249 	}
250 
251 	/* Disable axidcg clock gating during init */
252 	mmio_clrbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
253 
254 	stm32mp1_ddr_init(priv, &config);
255 
256 	/* Enable axidcg clock gating */
257 	mmio_setbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
258 
259 	priv->info.size = config.info.size;
260 
261 	VERBOSE("%s : ram size(%x, %x)\n", __func__,
262 		(uint32_t)priv->info.base, (uint32_t)priv->info.size);
263 
264 	dcsw_op_all(DC_OP_CISW);
265 	write_sctlr(read_sctlr() & ~SCTLR_C_BIT);
266 
267 	uret = ddr_test_data_bus();
268 	if (uret != 0U) {
269 		ERROR("DDR data bus test: can't access memory @ 0x%x\n",
270 		      uret);
271 		panic();
272 	}
273 
274 	uret = ddr_test_addr_bus();
275 	if (uret != 0U) {
276 		ERROR("DDR addr bus test: can't access memory @ 0x%x\n",
277 		      uret);
278 		panic();
279 	}
280 
281 	uret = ddr_check_size();
282 	if (uret < config.info.size) {
283 		ERROR("DDR size: 0x%x does not match DT config: 0x%x\n",
284 		      uret, config.info.size);
285 		panic();
286 	}
287 
288 	write_sctlr(read_sctlr() | SCTLR_C_BIT);
289 
290 	return 0;
291 }
292 
293 int stm32mp1_ddr_probe(void)
294 {
295 	struct ddr_info *priv = &ddr_priv_data;
296 
297 	VERBOSE("STM32MP DDR probe\n");
298 
299 	priv->ctl = (struct stm32mp1_ddrctl *)DDRCTRL_BASE;
300 	priv->phy = (struct stm32mp1_ddrphy *)DDRPHYC_BASE;
301 	priv->pwr = PWR_BASE;
302 	priv->rcc = RCC_BASE;
303 
304 	priv->info.base = STM32MP1_DDR_BASE;
305 	priv->info.size = 0;
306 
307 	return stm32mp1_ddr_setup();
308 }
309