1 /*
2 * Copyright (C) 2018-2019, 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_ddr.h>
16 #include <drivers/st/stm32mp1_ddr_helpers.h>
17 #include <drivers/st/stm32mp1_ram.h>
18 #include <lib/mmio.h>
19
20 #define DDR_PATTERN 0xAAAAAAAAU
21 #define DDR_ANTIPATTERN 0x55555555U
22
23 static struct ddr_info ddr_priv_data;
24
stm32mp1_ddr_clk_enable(struct ddr_info * priv,uint32_t mem_speed)25 int stm32mp1_ddr_clk_enable(struct ddr_info *priv, uint32_t mem_speed)
26 {
27 unsigned long ddrphy_clk, ddr_clk, mem_speed_hz;
28
29 ddr_enable_clock();
30
31 ddrphy_clk = stm32mp_clk_get_rate(DDRPHYC);
32
33 VERBOSE("DDR: mem_speed (%d kHz), RCC %ld kHz\n",
34 mem_speed, ddrphy_clk / 1000U);
35
36 mem_speed_hz = mem_speed * 1000U;
37
38 /* Max 10% frequency delta */
39 if (ddrphy_clk > mem_speed_hz) {
40 ddr_clk = ddrphy_clk - mem_speed_hz;
41 } else {
42 ddr_clk = mem_speed_hz - ddrphy_clk;
43 }
44 if (ddr_clk > (mem_speed_hz / 10)) {
45 ERROR("DDR expected freq %d kHz, current is %ld kHz\n",
46 mem_speed, ddrphy_clk / 1000U);
47 return -1;
48 }
49 return 0;
50 }
51
52 /*******************************************************************************
53 * This function tests the DDR data bus wiring.
54 * This is inspired from the Data Bus Test algorithm written by Michael Barr
55 * in "Programming Embedded Systems in C and C++" book.
56 * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
57 * File: memtest.c - This source code belongs to Public Domain.
58 * Returns 0 if success, and address value else.
59 ******************************************************************************/
ddr_test_data_bus(void)60 static uint32_t ddr_test_data_bus(void)
61 {
62 uint32_t pattern;
63
64 for (pattern = 1U; pattern != 0U; pattern <<= 1) {
65 mmio_write_32(STM32MP_DDR_BASE, pattern);
66
67 if (mmio_read_32(STM32MP_DDR_BASE) != pattern) {
68 return (uint32_t)STM32MP_DDR_BASE;
69 }
70 }
71
72 return 0;
73 }
74
75 /*******************************************************************************
76 * This function tests the DDR address bus wiring.
77 * This is inspired from the Data Bus Test algorithm written by Michael Barr
78 * in "Programming Embedded Systems in C and C++" book.
79 * resources.oreilly.com/examples/9781565923546/blob/master/Chapter6/
80 * File: memtest.c - This source code belongs to Public Domain.
81 * Returns 0 if success, and address value else.
82 ******************************************************************************/
ddr_test_addr_bus(void)83 static uint32_t ddr_test_addr_bus(void)
84 {
85 uint64_t addressmask = (ddr_priv_data.info.size - 1U);
86 uint64_t offset;
87 uint64_t testoffset = 0;
88
89 /* Write the default pattern at each of the power-of-two offsets. */
90 for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
91 offset <<= 1) {
92 mmio_write_32(STM32MP_DDR_BASE + (uint32_t)offset,
93 DDR_PATTERN);
94 }
95
96 /* Check for address bits stuck high. */
97 mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
98 DDR_ANTIPATTERN);
99
100 for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
101 offset <<= 1) {
102 if (mmio_read_32(STM32MP_DDR_BASE + (uint32_t)offset) !=
103 DDR_PATTERN) {
104 return (uint32_t)(STM32MP_DDR_BASE + offset);
105 }
106 }
107
108 mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset, DDR_PATTERN);
109
110 /* Check for address bits stuck low or shorted. */
111 for (testoffset = sizeof(uint32_t); (testoffset & addressmask) != 0U;
112 testoffset <<= 1) {
113 mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
114 DDR_ANTIPATTERN);
115
116 if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) {
117 return STM32MP_DDR_BASE;
118 }
119
120 for (offset = sizeof(uint32_t); (offset & addressmask) != 0U;
121 offset <<= 1) {
122 if ((mmio_read_32(STM32MP_DDR_BASE +
123 (uint32_t)offset) != DDR_PATTERN) &&
124 (offset != testoffset)) {
125 return (uint32_t)(STM32MP_DDR_BASE + offset);
126 }
127 }
128
129 mmio_write_32(STM32MP_DDR_BASE + (uint32_t)testoffset,
130 DDR_PATTERN);
131 }
132
133 return 0;
134 }
135
136 /*******************************************************************************
137 * This function checks the DDR size. It has to be run with Data Cache off.
138 * This test is run before data have been put in DDR, and is only done for
139 * cold boot. The DDR data can then be overwritten, and it is not useful to
140 * restore its content.
141 * Returns DDR computed size.
142 ******************************************************************************/
ddr_check_size(void)143 static uint32_t ddr_check_size(void)
144 {
145 uint32_t offset = sizeof(uint32_t);
146
147 mmio_write_32(STM32MP_DDR_BASE, DDR_PATTERN);
148
149 while (offset < STM32MP_DDR_MAX_SIZE) {
150 mmio_write_32(STM32MP_DDR_BASE + offset, DDR_ANTIPATTERN);
151 dsb();
152
153 if (mmio_read_32(STM32MP_DDR_BASE) != DDR_PATTERN) {
154 break;
155 }
156
157 offset <<= 1;
158 }
159
160 INFO("Memory size = 0x%x (%d MB)\n", offset, offset / (1024U * 1024U));
161
162 return offset;
163 }
164
stm32mp1_ddr_setup(void)165 static int stm32mp1_ddr_setup(void)
166 {
167 struct ddr_info *priv = &ddr_priv_data;
168 int ret;
169 struct stm32mp1_ddr_config config;
170 int node, len;
171 uint32_t uret, idx;
172 void *fdt;
173
174 #define PARAM(x, y) \
175 { \
176 .name = x, \
177 .offset = offsetof(struct stm32mp1_ddr_config, y), \
178 .size = sizeof(config.y) / sizeof(uint32_t) \
179 }
180
181 #define CTL_PARAM(x) PARAM("st,ctl-"#x, c_##x)
182 #define PHY_PARAM(x) PARAM("st,phy-"#x, p_##x)
183
184 const struct {
185 const char *name; /* Name in DT */
186 const uint32_t offset; /* Offset in config struct */
187 const uint32_t size; /* Size of parameters */
188 } param[] = {
189 CTL_PARAM(reg),
190 CTL_PARAM(timing),
191 CTL_PARAM(map),
192 CTL_PARAM(perf),
193 PHY_PARAM(reg),
194 PHY_PARAM(timing),
195 PHY_PARAM(cal)
196 };
197
198 if (fdt_get_address(&fdt) == 0) {
199 return -ENOENT;
200 }
201
202 node = fdt_node_offset_by_compatible(fdt, -1, DT_DDR_COMPAT);
203 if (node < 0) {
204 ERROR("%s: Cannot read DDR node in DT\n", __func__);
205 return -EINVAL;
206 }
207
208 config.info.speed = fdt_read_uint32_default(node, "st,mem-speed", 0);
209 if (!config.info.speed) {
210 VERBOSE("%s: no st,mem-speed\n", __func__);
211 return -EINVAL;
212 }
213 config.info.size = fdt_read_uint32_default(node, "st,mem-size", 0);
214 if (!config.info.size) {
215 VERBOSE("%s: no st,mem-size\n", __func__);
216 return -EINVAL;
217 }
218 config.info.name = fdt_getprop(fdt, node, "st,mem-name", &len);
219 if (config.info.name == NULL) {
220 VERBOSE("%s: no st,mem-name\n", __func__);
221 return -EINVAL;
222 }
223 INFO("RAM: %s\n", config.info.name);
224
225 for (idx = 0; idx < ARRAY_SIZE(param); idx++) {
226 ret = fdt_read_uint32_array(node, param[idx].name,
227 (void *)((uintptr_t)&config +
228 param[idx].offset),
229 param[idx].size);
230
231 VERBOSE("%s: %s[0x%x] = %d\n", __func__,
232 param[idx].name, param[idx].size, ret);
233 if (ret != 0) {
234 ERROR("%s: Cannot read %s\n",
235 __func__, param[idx].name);
236 return -EINVAL;
237 }
238 }
239
240 /* Disable axidcg clock gating during init */
241 mmio_clrbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
242
243 stm32mp1_ddr_init(priv, &config);
244
245 /* Enable axidcg clock gating */
246 mmio_setbits_32(priv->rcc + RCC_DDRITFCR, RCC_DDRITFCR_AXIDCGEN);
247
248 priv->info.size = config.info.size;
249
250 VERBOSE("%s : ram size(%x, %x)\n", __func__,
251 (uint32_t)priv->info.base, (uint32_t)priv->info.size);
252
253 write_sctlr(read_sctlr() & ~SCTLR_C_BIT);
254 dcsw_op_all(DC_OP_CISW);
255
256 uret = ddr_test_data_bus();
257 if (uret != 0U) {
258 ERROR("DDR data bus test: can't access memory @ 0x%x\n",
259 uret);
260 panic();
261 }
262
263 uret = ddr_test_addr_bus();
264 if (uret != 0U) {
265 ERROR("DDR addr bus test: can't access memory @ 0x%x\n",
266 uret);
267 panic();
268 }
269
270 uret = ddr_check_size();
271 if (uret < config.info.size) {
272 ERROR("DDR size: 0x%x does not match DT config: 0x%x\n",
273 uret, config.info.size);
274 panic();
275 }
276
277 write_sctlr(read_sctlr() | SCTLR_C_BIT);
278
279 return 0;
280 }
281
stm32mp1_ddr_probe(void)282 int stm32mp1_ddr_probe(void)
283 {
284 struct ddr_info *priv = &ddr_priv_data;
285
286 VERBOSE("STM32MP DDR probe\n");
287
288 priv->ctl = (struct stm32mp1_ddrctl *)stm32mp_ddrctrl_base();
289 priv->phy = (struct stm32mp1_ddrphy *)stm32mp_ddrphyc_base();
290 priv->pwr = stm32mp_pwr_base();
291 priv->rcc = stm32mp_rcc_base();
292
293 priv->info.base = STM32MP_DDR_BASE;
294 priv->info.size = 0;
295
296 return stm32mp1_ddr_setup();
297 }
298