xref: /openbmc/u-boot/drivers/ram/stm32_sdram.c (revision db00e921)
1 /*
2  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
3  * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <clk.h>
10 #include <dm.h>
11 #include <ram.h>
12 #include <asm/io.h>
13 
14 #define MEM_MODE_MASK	GENMASK(2, 0)
15 #define NOT_FOUND	0xff
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 struct stm32_fmc_regs {
20 	/* 0x0 */
21 	u32 bcr1;	/* NOR/PSRAM Chip select control register 1 */
22 	u32 btr1;	/* SRAM/NOR-Flash Chip select timing register 1 */
23 	u32 bcr2;	/* NOR/PSRAM Chip select Control register 2 */
24 	u32 btr2;	/* SRAM/NOR-Flash Chip select timing register 2 */
25 	u32 bcr3;	/* NOR/PSRAMChip select Control register 3 */
26 	u32 btr3;	/* SRAM/NOR-Flash Chip select timing register 3 */
27 	u32 bcr4;	/* NOR/PSRAM Chip select Control register 4 */
28 	u32 btr4;	/* SRAM/NOR-Flash Chip select timing register 4 */
29 	u32 reserved1[24];
30 
31 	/* 0x80 */
32 	u32 pcr;	/* NAND Flash control register */
33 	u32 sr;		/* FIFO status and interrupt register */
34 	u32 pmem;	/* Common memory space timing register */
35 	u32 patt;	/* Attribute memory space timing registers  */
36 	u32 reserved2[1];
37 	u32 eccr;	/* ECC result registers */
38 	u32 reserved3[27];
39 
40 	/* 0x104 */
41 	u32 bwtr1;	/* SRAM/NOR-Flash write timing register 1 */
42 	u32 reserved4[1];
43 	u32 bwtr2;	/* SRAM/NOR-Flash write timing register 2 */
44 	u32 reserved5[1];
45 	u32 bwtr3;	/* SRAM/NOR-Flash write timing register 3 */
46 	u32 reserved6[1];
47 	u32 bwtr4;	/* SRAM/NOR-Flash write timing register 4 */
48 	u32 reserved7[8];
49 
50 	/* 0x140 */
51 	u32 sdcr1;	/* SDRAM Control register 1 */
52 	u32 sdcr2;	/* SDRAM Control register 2 */
53 	u32 sdtr1;	/* SDRAM Timing register 1 */
54 	u32 sdtr2;	/* SDRAM Timing register 2 */
55 	u32 sdcmr;	/* SDRAM Mode register */
56 	u32 sdrtr;	/* SDRAM Refresh timing register */
57 	u32 sdsr;	/* SDRAM Status register */
58 };
59 
60 /*
61  * NOR/PSRAM Control register BCR1
62  * FMC controller Enable, only availabe for H7
63  */
64 #define FMC_BCR1_FMCEN		BIT(31)
65 
66 /* Control register SDCR */
67 #define FMC_SDCR_RPIPE_SHIFT	13	/* RPIPE bit shift */
68 #define FMC_SDCR_RBURST_SHIFT	12	/* RBURST bit shift */
69 #define FMC_SDCR_SDCLK_SHIFT	10	/* SDRAM clock divisor shift */
70 #define FMC_SDCR_WP_SHIFT	9	/* Write protection shift */
71 #define FMC_SDCR_CAS_SHIFT	7	/* CAS latency shift */
72 #define FMC_SDCR_NB_SHIFT	6	/* Number of banks shift */
73 #define FMC_SDCR_MWID_SHIFT	4	/* Memory width shift */
74 #define FMC_SDCR_NR_SHIFT	2	/* Number of row address bits shift */
75 #define FMC_SDCR_NC_SHIFT	0	/* Number of col address bits shift */
76 
77 /* Timings register SDTR */
78 #define FMC_SDTR_TMRD_SHIFT	0	/* Load mode register to active */
79 #define FMC_SDTR_TXSR_SHIFT	4	/* Exit self-refresh time */
80 #define FMC_SDTR_TRAS_SHIFT	8	/* Self-refresh time */
81 #define FMC_SDTR_TRC_SHIFT	12	/* Row cycle delay */
82 #define FMC_SDTR_TWR_SHIFT	16	/* Recovery delay */
83 #define FMC_SDTR_TRP_SHIFT	20	/* Row precharge delay */
84 #define FMC_SDTR_TRCD_SHIFT	24	/* Row-to-column delay */
85 
86 #define FMC_SDCMR_NRFS_SHIFT	5
87 
88 #define FMC_SDCMR_MODE_NORMAL		0
89 #define FMC_SDCMR_MODE_START_CLOCK	1
90 #define FMC_SDCMR_MODE_PRECHARGE	2
91 #define FMC_SDCMR_MODE_AUTOREFRESH	3
92 #define FMC_SDCMR_MODE_WRITE_MODE	4
93 #define FMC_SDCMR_MODE_SELFREFRESH	5
94 #define FMC_SDCMR_MODE_POWERDOWN	6
95 
96 #define FMC_SDCMR_BANK_1		BIT(4)
97 #define FMC_SDCMR_BANK_2		BIT(3)
98 
99 #define FMC_SDCMR_MODE_REGISTER_SHIFT	9
100 
101 #define FMC_SDSR_BUSY			BIT(5)
102 
103 #define FMC_BUSY_WAIT(regs)	do { \
104 		__asm__ __volatile__ ("dsb" : : : "memory"); \
105 		while (regs->sdsr & FMC_SDSR_BUSY) \
106 			; \
107 	} while (0)
108 
109 struct stm32_sdram_control {
110 	u8 no_columns;
111 	u8 no_rows;
112 	u8 memory_width;
113 	u8 no_banks;
114 	u8 cas_latency;
115 	u8 sdclk;
116 	u8 rd_burst;
117 	u8 rd_pipe_delay;
118 };
119 
120 struct stm32_sdram_timing {
121 	u8 tmrd;
122 	u8 txsr;
123 	u8 tras;
124 	u8 trc;
125 	u8 trp;
126 	u8 twr;
127 	u8 trcd;
128 };
129 enum stm32_fmc_bank {
130 	SDRAM_BANK1,
131 	SDRAM_BANK2,
132 	MAX_SDRAM_BANK,
133 };
134 
135 enum stm32_fmc_family {
136 	STM32F7_FMC,
137 	STM32H7_FMC,
138 };
139 
140 struct bank_params {
141 	struct stm32_sdram_control *sdram_control;
142 	struct stm32_sdram_timing *sdram_timing;
143 	u32 sdram_ref_count;
144 	enum stm32_fmc_bank target_bank;
145 };
146 
147 struct stm32_sdram_params {
148 	struct stm32_fmc_regs *base;
149 	u8 no_sdram_banks;
150 	struct bank_params bank_params[MAX_SDRAM_BANK];
151 	enum stm32_fmc_family family;
152 };
153 
154 #define SDRAM_MODE_BL_SHIFT	0
155 #define SDRAM_MODE_CAS_SHIFT	4
156 #define SDRAM_MODE_BL		0
157 
158 int stm32_sdram_init(struct udevice *dev)
159 {
160 	struct stm32_sdram_params *params = dev_get_platdata(dev);
161 	struct stm32_sdram_control *control;
162 	struct stm32_sdram_timing *timing;
163 	struct stm32_fmc_regs *regs = params->base;
164 	enum stm32_fmc_bank target_bank;
165 	u32 ctb; /* SDCMR register: Command Target Bank */
166 	u32 ref_count;
167 	u8 i;
168 
169 	/* disable the FMC controller */
170 	if (params->family == STM32H7_FMC)
171 		clrbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
172 
173 	for (i = 0; i < params->no_sdram_banks; i++) {
174 		control = params->bank_params[i].sdram_control;
175 		timing = params->bank_params[i].sdram_timing;
176 		target_bank = params->bank_params[i].target_bank;
177 		ref_count = params->bank_params[i].sdram_ref_count;
178 
179 		writel(control->sdclk << FMC_SDCR_SDCLK_SHIFT
180 			| control->cas_latency << FMC_SDCR_CAS_SHIFT
181 			| control->no_banks << FMC_SDCR_NB_SHIFT
182 			| control->memory_width << FMC_SDCR_MWID_SHIFT
183 			| control->no_rows << FMC_SDCR_NR_SHIFT
184 			| control->no_columns << FMC_SDCR_NC_SHIFT
185 			| control->rd_pipe_delay << FMC_SDCR_RPIPE_SHIFT
186 			| control->rd_burst << FMC_SDCR_RBURST_SHIFT,
187 			&regs->sdcr1);
188 
189 		if (target_bank == SDRAM_BANK2)
190 			writel(control->cas_latency << FMC_SDCR_CAS_SHIFT
191 				| control->no_banks << FMC_SDCR_NB_SHIFT
192 				| control->memory_width << FMC_SDCR_MWID_SHIFT
193 				| control->no_rows << FMC_SDCR_NR_SHIFT
194 				| control->no_columns << FMC_SDCR_NC_SHIFT,
195 				&regs->sdcr2);
196 
197 		writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
198 			| timing->trp << FMC_SDTR_TRP_SHIFT
199 			| timing->twr << FMC_SDTR_TWR_SHIFT
200 			| timing->trc << FMC_SDTR_TRC_SHIFT
201 			| timing->tras << FMC_SDTR_TRAS_SHIFT
202 			| timing->txsr << FMC_SDTR_TXSR_SHIFT
203 			| timing->tmrd << FMC_SDTR_TMRD_SHIFT,
204 			&regs->sdtr1);
205 
206 		if (target_bank == SDRAM_BANK2)
207 			writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
208 				| timing->trp << FMC_SDTR_TRP_SHIFT
209 				| timing->twr << FMC_SDTR_TWR_SHIFT
210 				| timing->trc << FMC_SDTR_TRC_SHIFT
211 				| timing->tras << FMC_SDTR_TRAS_SHIFT
212 				| timing->txsr << FMC_SDTR_TXSR_SHIFT
213 				| timing->tmrd << FMC_SDTR_TMRD_SHIFT,
214 				&regs->sdtr2);
215 
216 		if (target_bank == SDRAM_BANK1)
217 			ctb = FMC_SDCMR_BANK_1;
218 		else
219 			ctb = FMC_SDCMR_BANK_2;
220 
221 		writel(ctb | FMC_SDCMR_MODE_START_CLOCK, &regs->sdcmr);
222 		udelay(200);	/* 200 us delay, page 10, "Power-Up" */
223 		FMC_BUSY_WAIT(regs);
224 
225 		writel(ctb | FMC_SDCMR_MODE_PRECHARGE, &regs->sdcmr);
226 		udelay(100);
227 		FMC_BUSY_WAIT(regs);
228 
229 		writel((ctb | FMC_SDCMR_MODE_AUTOREFRESH | 7 << FMC_SDCMR_NRFS_SHIFT),
230 		       &regs->sdcmr);
231 		udelay(100);
232 		FMC_BUSY_WAIT(regs);
233 
234 		writel(ctb | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT
235 		       | control->cas_latency << SDRAM_MODE_CAS_SHIFT)
236 		       << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE,
237 		       &regs->sdcmr);
238 		udelay(100);
239 		FMC_BUSY_WAIT(regs);
240 
241 		writel(ctb | FMC_SDCMR_MODE_NORMAL, &regs->sdcmr);
242 		FMC_BUSY_WAIT(regs);
243 
244 		/* Refresh timer */
245 		writel(ref_count << 1, &regs->sdrtr);
246 	}
247 
248 	/* enable the FMC controller */
249 	if (params->family == STM32H7_FMC)
250 		setbits_le32(&regs->bcr1, FMC_BCR1_FMCEN);
251 
252 	return 0;
253 }
254 
255 static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
256 {
257 	struct stm32_sdram_params *params = dev_get_platdata(dev);
258 	struct bank_params *bank_params;
259 	struct ofnode_phandle_args args;
260 	u32 *syscfg_base;
261 	u32 mem_remap;
262 	ofnode bank_node;
263 	char *bank_name;
264 	u8 bank = 0;
265 	int ret;
266 
267 	mem_remap = dev_read_u32_default(dev, "st,mem_remap", NOT_FOUND);
268 	if (mem_remap != NOT_FOUND) {
269 		ret = dev_read_phandle_with_args(dev, "st,syscfg", NULL, 0, 0,
270 						 &args);
271 		if (ret) {
272 			debug("%s: can't find syscon device (%d)\n", __func__,
273 			      ret);
274 			return ret;
275 		}
276 
277 		syscfg_base = (u32 *)ofnode_get_addr(args.node);
278 
279 		/* set memory mapping selection */
280 		clrsetbits_le32(syscfg_base, MEM_MODE_MASK, mem_remap);
281 	} else {
282 		debug("%s: cannot find st,mem_remap property\n", __func__);
283 	}
284 
285 	dev_for_each_subnode(bank_node, dev) {
286 		/* extract the bank index from DT */
287 		bank_name = (char *)ofnode_get_name(bank_node);
288 		strsep(&bank_name, "@");
289 		if (!bank_name) {
290 			pr_err("missing sdram bank index");
291 			return -EINVAL;
292 		}
293 
294 		bank_params = &params->bank_params[bank];
295 		strict_strtoul(bank_name, 10,
296 			       (long unsigned int *)&bank_params->target_bank);
297 
298 		if (bank_params->target_bank >= MAX_SDRAM_BANK) {
299 			pr_err("Found bank %d , but only bank 0 and 1 are supported",
300 			      bank_params->target_bank);
301 			return -EINVAL;
302 		}
303 
304 		debug("Find bank %s %u\n", bank_name, bank_params->target_bank);
305 
306 		params->bank_params[bank].sdram_control =
307 			(struct stm32_sdram_control *)
308 			 ofnode_read_u8_array_ptr(bank_node,
309 						  "st,sdram-control",
310 						  sizeof(struct stm32_sdram_control));
311 
312 		if (!params->bank_params[bank].sdram_control) {
313 			pr_err("st,sdram-control not found for %s",
314 			      ofnode_get_name(bank_node));
315 			return -EINVAL;
316 		}
317 
318 
319 		params->bank_params[bank].sdram_timing =
320 			(struct stm32_sdram_timing *)
321 			 ofnode_read_u8_array_ptr(bank_node,
322 						  "st,sdram-timing",
323 						  sizeof(struct stm32_sdram_timing));
324 
325 		if (!params->bank_params[bank].sdram_timing) {
326 			pr_err("st,sdram-timing not found for %s",
327 			      ofnode_get_name(bank_node));
328 			return -EINVAL;
329 		}
330 
331 
332 		bank_params->sdram_ref_count = ofnode_read_u32_default(bank_node,
333 						"st,sdram-refcount", 8196);
334 		bank++;
335 	}
336 
337 	params->no_sdram_banks = bank;
338 	debug("%s, no of banks = %d\n", __func__, params->no_sdram_banks);
339 
340 	return 0;
341 }
342 
343 static int stm32_fmc_probe(struct udevice *dev)
344 {
345 	struct stm32_sdram_params *params = dev_get_platdata(dev);
346 	int ret;
347 	fdt_addr_t addr;
348 
349 	addr = dev_read_addr(dev);
350 	if (addr == FDT_ADDR_T_NONE)
351 		return -EINVAL;
352 
353 	params->base = (struct stm32_fmc_regs *)addr;
354 	params->family = dev_get_driver_data(dev);
355 
356 #ifdef CONFIG_CLK
357 	struct clk clk;
358 
359 	ret = clk_get_by_index(dev, 0, &clk);
360 	if (ret < 0)
361 		return ret;
362 
363 	ret = clk_enable(&clk);
364 
365 	if (ret) {
366 		dev_err(dev, "failed to enable clock\n");
367 		return ret;
368 	}
369 #endif
370 	ret = stm32_sdram_init(dev);
371 	if (ret)
372 		return ret;
373 
374 	return 0;
375 }
376 
377 static int stm32_fmc_get_info(struct udevice *dev, struct ram_info *info)
378 {
379 	return 0;
380 }
381 
382 static struct ram_ops stm32_fmc_ops = {
383 	.get_info = stm32_fmc_get_info,
384 };
385 
386 static const struct udevice_id stm32_fmc_ids[] = {
387 	{ .compatible = "st,stm32-fmc", .data = STM32F7_FMC },
388 	{ .compatible = "st,stm32h7-fmc", .data = STM32H7_FMC },
389 	{ }
390 };
391 
392 U_BOOT_DRIVER(stm32_fmc) = {
393 	.name = "stm32_fmc",
394 	.id = UCLASS_RAM,
395 	.of_match = stm32_fmc_ids,
396 	.ops = &stm32_fmc_ops,
397 	.ofdata_to_platdata = stm32_fmc_ofdata_to_platdata,
398 	.probe = stm32_fmc_probe,
399 	.platdata_auto_alloc_size = sizeof(struct stm32_sdram_params),
400 };
401