xref: /rk3399_ARM-atf/drivers/st/ddr/stm32mp1_ram.c (revision 33667d299bd5398ca549f542345e0f321b483d17)
1 /*
2  * Copyright (C) 2018-2021, 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 <common/fdt_wrappers.h>
16 #include <drivers/clk.h>
17 #include <drivers/st/stm32mp1_ddr.h>
18 #include <drivers/st/stm32mp1_ddr_helpers.h>
19 #include <drivers/st/stm32mp1_ram.h>
20 #include <lib/mmio.h>
21 
22 #define DDR_PATTERN	0xAAAAAAAAU
23 #define DDR_ANTIPATTERN	0x55555555U
24 
25 static struct ddr_info ddr_priv_data;
26 
27 int stm32mp1_ddr_clk_enable(struct ddr_info *priv, uint32_t mem_speed)
28 {
29 	unsigned long ddrphy_clk, ddr_clk, mem_speed_hz;
30 
31 	ddr_enable_clock();
32 
33 	ddrphy_clk = clk_get_rate(DDRPHYC);
34 
35 	VERBOSE("DDR: mem_speed (%d kHz), RCC %ld kHz\n",
36 		mem_speed, ddrphy_clk / 1000U);
37 
38 	mem_speed_hz = mem_speed * 1000U;
39 
40 	/* Max 10% frequency delta */
41 	if (ddrphy_clk > mem_speed_hz) {
42 		ddr_clk = ddrphy_clk - mem_speed_hz;
43 	} else {
44 		ddr_clk = mem_speed_hz - ddrphy_clk;
45 	}
46 	if (ddr_clk > (mem_speed_hz / 10)) {
47 		ERROR("DDR expected freq %d kHz, current is %ld kHz\n",
48 		      mem_speed, ddrphy_clk / 1000U);
49 		return -1;
50 	}
51 	return 0;
52 }
53 
54 /*******************************************************************************
55  * This function tests the DDR data bus wiring.
56  * This is inspired from the Data Bus Test algorithm written by Michael Barr
57  * in "Programming Embedded Systems in C and C++" book.
58  * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
59  * File: memtest.c - This source code belongs to Public Domain.
60  * Returns 0 if success, and address value else.
61  ******************************************************************************/
62 static uint32_t ddr_test_data_bus(void)
63 {
64 	uint32_t pattern;
65 
66 	for (pattern = 1U; pattern != 0U; pattern <<= 1) {
67 		mmio_write_32(STM32MP_DDR_BASE, pattern);
68 
69 		if (mmio_read_32(STM32MP_DDR_BASE) != pattern) {
70 			return (uint32_t)STM32MP_DDR_BASE;
71 		}
72 	}
73 
74 	return 0;
75 }
76 
77 /*******************************************************************************
78  * This function tests the DDR address bus wiring.
79  * This is inspired from the Data Bus Test algorithm written by Michael Barr
80  * in "Programming Embedded Systems in C and C++" book.
81  * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
82  * File: memtest.c - This source code belongs to Public Domain.
83  * Returns 0 if success, and address value else.
84  ******************************************************************************/
85 static uint32_t ddr_test_addr_bus(void)
86 {
87 	uint64_t addressmask = (ddr_priv_data.info.size - 1U);
88 	uint64_t offset;
89 	uint64_t testoffset = 0;
90 
91 	/* Write the default pattern at each of the power-of-two offsets. */
92 	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
93 	     offset <<= 1) {
94 		mmio_write_32(STM32MP_DDR_BASE + (uint32_t)offset,
95 			      DDR_PATTERN);
96 	}
97 
98 	/* Check for address bits stuck high. */
99 	mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
100 		      DDR_ANTIPATTERN);
101 
102 	for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
103 	     offset <<= 1) {
104 		if (mmio_read_32(STM32MP_DDR_BASE + (uint32_t)offset) !=
105 		    DDR_PATTERN) {
106 			return (uint32_t)(STM32MP_DDR_BASE + offset);
107 		}
108 	}
109 
110 	mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN);
111 
112 	/* Check for address bits stuck low or shorted. */
113 	for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U;
114 	     testoffset <<= 1) {
115 		mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
116 			      DDR_ANTIPATTERN);
117 
118 		if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) {
119 			return STM32MP_DDR_BASE;
120 		}
121 
122 		for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
123 		     offset <<= 1) {
124 			if ((mmio_read_32(STM32MP_DDR_BASE +
125 					  (uint32_t)offset) != DDR_PATTERN) &&
126 			    (offset != testoffset)) {
127 				return (uint32_t)(STM32MP_DDR_BASE + offset);
128 			}
129 		}
130 
131 		mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
132 			      DDR_PATTERN);
133 	}
134 
135 	return 0;
136 }
137 
138 /*******************************************************************************
139  * This function checks the DDR size. It has to be run with Data Cache off.
140  * This test is run before data have been put in DDR, and is only done for
141  * cold boot. The DDR data can then be overwritten, and it is not useful to
142  * restore its content.
143  * Returns DDR computed size.
144  ******************************************************************************/
145 static uint32_t ddr_check_size(void)
146 {
147 	uint32_t offset = sizeof(uint32_t);
148 
149 	mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN);
150 
151 	while (offset < STM32MP_DDR_MAX_SIZE) {
152 		mmio_write_32(STM32MP_DDR_BASE + offset, DDR_ANTIPATTERN);
153 		dsb();
154 
155 		if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) {
156 			break;
157 		}
158 
159 		offset <<= 1;
160 	}
161 
162 	INFO("Memory size = 0x%x (%d MB)\n", offset, offset / (1024U * 1024U));
163 
164 	return offset;
165 }
166 
167 static int stm32mp1_ddr_setup(void)
168 {
169 	struct ddr_info *priv = &ddr_priv_data;
170 	int ret;
171 	struct stm32mp1_ddr_config config;
172 	int node, len;
173 	uint32_t uret, idx;
174 	void *fdt;
175 
176 #define PARAM(x, y)							\
177 	{								\
178 		.name = x,						\
179 		.offset = offsetof(struct stm32mp1_ddr_config, y),	\
180 		.size = sizeof(config.y) / sizeof(uint32_t)		\
181 	}
182 
183 #define CTL_PARAM(x) PARAM("st,ctl-"#x, c_##x)
184 #define PHY_PARAM(x) PARAM("st,phy-"#x, p_##x)
185 
186 	const struct {
187 		const char *name; /* Name in DT */
188 		const uint32_t offset; /* Offset in config struct */
189 		const uint32_t size;   /* Size of parameters */
190 	} param[] = {
191 		CTL_PARAM(reg),
192 		CTL_PARAM(timing),
193 		CTL_PARAM(map),
194 		CTL_PARAM(perf),
195 		PHY_PARAM(reg),
196 		PHY_PARAM(timing),
197 		PHY_PARAM(cal)
198 	};
199 
200 	if (fdt_get_address(&fdt) == 0) {
201 		return -ENOENT;
202 	}
203 
204 	node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
205 	if (node < 0) {
206 		ERROR("%s: Cannot read DDR node in DT\n", __func__);
207 		return -EINVAL;
208 	}
209 
210 	ret = fdt_read_uint32(fdt, node, "st,mem-speed", &config.info.speed);
211 	if (ret < 0) {
212 		VERBOSE("%s: no st,mem-speed\n", __func__);
213 		return -EINVAL;
214 	}
215 	ret = fdt_read_uint32(fdt, node, "st,mem-size", &config.info.size);
216 	if (ret < 0) {
217 		VERBOSE("%s: no st,mem-size\n", __func__);
218 		return -EINVAL;
219 	}
220 	config.info.name = fdt_getprop(fdt, node, "st,mem-name", &len);
221 	if (config.info.name == NULL) {
222 		VERBOSE("%s: no st,mem-name\n", __func__);
223 		return -EINVAL;
224 	}
225 	INFO("RAM: %s\n", config.info.name);
226 
227 	for (idx = 0; idx < ARRAY_SIZE(param); idx++) {
228 		ret = fdt_read_uint32_array(fdt, node, param[idx].name,
229 					    param[idx].size,
230 					    (void *)((uintptr_t)&config +
231 						     param[idx].offset));
232 
233 		VERBOSE("%s: %s[0x%x] = %d\n", __func__,
234 			param[idx].name, param[idx].size, ret);
235 		if (ret != 0) {
236 			ERROR("%s: Cannot read %s\n",
237 			      __func__, param[idx].name);
238 			return -EINVAL;
239 		}
240 	}
241 
242 	/* Disable axidcg clock gating during init */
243 	mmio_clrbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
244 
245 	stm32mp1_ddr_init(priv, &config);
246 
247 	/* Enable axidcg clock gating */
248 	mmio_setbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
249 
250 	priv->info.size = config.info.size;
251 
252 	VERBOSE("%s : ram size(%x, %x)\n", __func__,
253 		(uint32_t)priv->info.base, (uint32_t)priv->info.size);
254 
255 	if (stm32mp_map_ddr_non_cacheable() != 0) {
256 		panic();
257 	}
258 
259 	uret = ddr_test_data_bus();
260 	if (uret != 0U) {
261 		ERROR("DDR data bus test: can't access memory @ 0x%x\n",
262 		      uret);
263 		panic();
264 	}
265 
266 	uret = ddr_test_addr_bus();
267 	if (uret != 0U) {
268 		ERROR("DDR addr bus test: can't access memory @ 0x%x\n",
269 		      uret);
270 		panic();
271 	}
272 
273 	uret = ddr_check_size();
274 	if (uret < config.info.size) {
275 		ERROR("DDR size: 0x%x does not match DT config: 0x%x\n",
276 		      uret, config.info.size);
277 		panic();
278 	}
279 
280 	if (stm32mp_unmap_ddr() != 0) {
281 		panic();
282 	}
283 
284 	return 0;
285 }
286 
287 int stm32mp1_ddr_probe(void)
288 {
289 	struct ddr_info *priv = &ddr_priv_data;
290 
291 	VERBOSE("STM32MP DDR probe\n");
292 
293 	priv->ctl = (struct stm32mp1_ddrctl *)stm32mp_ddrctrl_base();
294 	priv->phy = (struct stm32mp1_ddrphy *)stm32mp_ddrphyc_base();
295 	priv->pwr = stm32mp_pwr_base();
296 	priv->rcc = stm32mp_rcc_base();
297 
298 	priv->info.base = STM32MP_DDR_BASE;
299 	priv->info.size = 0;
300 
301 	return stm32mp1_ddr_setup();
302 }
303