xref: /rk3399_rockchip-uboot/drivers/ram/stm32_sdram.c (revision f303aaf21b968ab959edcc354892f9eca8907e0b)
1 /*
2  * (C) Copyright 2017
3  * Vikas Manocha, <vikas.manocha@st.com>
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 DECLARE_GLOBAL_DATA_PTR;
15 
16 struct stm32_fmc_regs {
17 	/* 0x0 */
18 	u32 bcr1;	/* NOR/PSRAM Chip select control register 1 */
19 	u32 btr1;	/* SRAM/NOR-Flash Chip select timing register 1 */
20 	u32 bcr2;	/* NOR/PSRAM Chip select Control register 2 */
21 	u32 btr2;	/* SRAM/NOR-Flash Chip select timing register 2 */
22 	u32 bcr3;	/* NOR/PSRAMChip select Control register 3 */
23 	u32 btr3;	/* SRAM/NOR-Flash Chip select timing register 3 */
24 	u32 bcr4;	/* NOR/PSRAM Chip select Control register 4 */
25 	u32 btr4;	/* SRAM/NOR-Flash Chip select timing register 4 */
26 	u32 reserved1[24];
27 
28 	/* 0x80 */
29 	u32 pcr;	/* NAND Flash control register */
30 	u32 sr;		/* FIFO status and interrupt register */
31 	u32 pmem;	/* Common memory space timing register */
32 	u32 patt;	/* Attribute memory space timing registers  */
33 	u32 reserved2[1];
34 	u32 eccr;	/* ECC result registers */
35 	u32 reserved3[27];
36 
37 	/* 0x104 */
38 	u32 bwtr1;	/* SRAM/NOR-Flash write timing register 1 */
39 	u32 reserved4[1];
40 	u32 bwtr2;	/* SRAM/NOR-Flash write timing register 2 */
41 	u32 reserved5[1];
42 	u32 bwtr3;	/* SRAM/NOR-Flash write timing register 3 */
43 	u32 reserved6[1];
44 	u32 bwtr4;	/* SRAM/NOR-Flash write timing register 4 */
45 	u32 reserved7[8];
46 
47 	/* 0x140 */
48 	u32 sdcr1;	/* SDRAM Control register 1 */
49 	u32 sdcr2;	/* SDRAM Control register 2 */
50 	u32 sdtr1;	/* SDRAM Timing register 1 */
51 	u32 sdtr2;	/* SDRAM Timing register 2 */
52 	u32 sdcmr;	/* SDRAM Mode register */
53 	u32 sdrtr;	/* SDRAM Refresh timing register */
54 	u32 sdsr;	/* SDRAM Status register */
55 };
56 
57 /* Control register SDCR */
58 #define FMC_SDCR_RPIPE_SHIFT	13	/* RPIPE bit shift */
59 #define FMC_SDCR_RBURST_SHIFT	12	/* RBURST bit shift */
60 #define FMC_SDCR_SDCLK_SHIFT	10	/* SDRAM clock divisor shift */
61 #define FMC_SDCR_WP_SHIFT	9	/* Write protection shift */
62 #define FMC_SDCR_CAS_SHIFT	7	/* CAS latency shift */
63 #define FMC_SDCR_NB_SHIFT	6	/* Number of banks shift */
64 #define FMC_SDCR_MWID_SHIFT	4	/* Memory width shift */
65 #define FMC_SDCR_NR_SHIFT	2	/* Number of row address bits shift */
66 #define FMC_SDCR_NC_SHIFT	0	/* Number of col address bits shift */
67 
68 /* Timings register SDTR */
69 #define FMC_SDTR_TMRD_SHIFT	0	/* Load mode register to active */
70 #define FMC_SDTR_TXSR_SHIFT	4	/* Exit self-refresh time */
71 #define FMC_SDTR_TRAS_SHIFT	8	/* Self-refresh time */
72 #define FMC_SDTR_TRC_SHIFT	12	/* Row cycle delay */
73 #define FMC_SDTR_TWR_SHIFT	16	/* Recovery delay */
74 #define FMC_SDTR_TRP_SHIFT	20	/* Row precharge delay */
75 #define FMC_SDTR_TRCD_SHIFT	24	/* Row-to-column delay */
76 
77 #define FMC_SDCMR_NRFS_SHIFT	5
78 
79 #define FMC_SDCMR_MODE_NORMAL		0
80 #define FMC_SDCMR_MODE_START_CLOCK	1
81 #define FMC_SDCMR_MODE_PRECHARGE	2
82 #define FMC_SDCMR_MODE_AUTOREFRESH	3
83 #define FMC_SDCMR_MODE_WRITE_MODE	4
84 #define FMC_SDCMR_MODE_SELFREFRESH	5
85 #define FMC_SDCMR_MODE_POWERDOWN	6
86 
87 #define FMC_SDCMR_BANK_1		BIT(4)
88 #define FMC_SDCMR_BANK_2		BIT(3)
89 
90 #define FMC_SDCMR_MODE_REGISTER_SHIFT	9
91 
92 #define FMC_SDSR_BUSY			BIT(5)
93 
94 #define FMC_BUSY_WAIT(regs)	do { \
95 		__asm__ __volatile__ ("dsb" : : : "memory"); \
96 		while (regs->sdsr & FMC_SDSR_BUSY) \
97 			; \
98 	} while (0)
99 
100 struct stm32_sdram_control {
101 	u8 no_columns;
102 	u8 no_rows;
103 	u8 memory_width;
104 	u8 no_banks;
105 	u8 cas_latency;
106 	u8 sdclk;
107 	u8 rd_burst;
108 	u8 rd_pipe_delay;
109 };
110 
111 struct stm32_sdram_timing {
112 	u8 tmrd;
113 	u8 txsr;
114 	u8 tras;
115 	u8 trc;
116 	u8 trp;
117 	u8 twr;
118 	u8 trcd;
119 };
120 enum stm32_fmc_bank {
121 	SDRAM_BANK1,
122 	SDRAM_BANK2,
123 	MAX_SDRAM_BANK,
124 };
125 
126 struct bank_params {
127 	struct stm32_sdram_control *sdram_control;
128 	struct stm32_sdram_timing *sdram_timing;
129 	u32 sdram_ref_count;
130 	enum stm32_fmc_bank target_bank;
131 };
132 
133 struct stm32_sdram_params {
134 	struct stm32_fmc_regs *base;
135 	u8 no_sdram_banks;
136 	struct bank_params bank_params[MAX_SDRAM_BANK];
137 };
138 
139 #define SDRAM_MODE_BL_SHIFT	0
140 #define SDRAM_MODE_CAS_SHIFT	4
141 #define SDRAM_MODE_BL		0
142 
143 int stm32_sdram_init(struct udevice *dev)
144 {
145 	struct stm32_sdram_params *params = dev_get_platdata(dev);
146 	struct stm32_sdram_control *control;
147 	struct stm32_sdram_timing *timing;
148 	struct stm32_fmc_regs *regs = params->base;
149 	enum stm32_fmc_bank target_bank;
150 	u32 ctb; /* SDCMR register: Command Target Bank */
151 	u32 ref_count;
152 	u8 i;
153 
154 	for (i = 0; i < params->no_sdram_banks; i++) {
155 		control = params->bank_params[i].sdram_control;
156 		timing = params->bank_params[i].sdram_timing;
157 		target_bank = params->bank_params[i].target_bank;
158 		ref_count = params->bank_params[i].sdram_ref_count;
159 
160 		writel(control->sdclk << FMC_SDCR_SDCLK_SHIFT
161 			| control->cas_latency << FMC_SDCR_CAS_SHIFT
162 			| control->no_banks << FMC_SDCR_NB_SHIFT
163 			| control->memory_width << FMC_SDCR_MWID_SHIFT
164 			| control->no_rows << FMC_SDCR_NR_SHIFT
165 			| control->no_columns << FMC_SDCR_NC_SHIFT
166 			| control->rd_pipe_delay << FMC_SDCR_RPIPE_SHIFT
167 			| control->rd_burst << FMC_SDCR_RBURST_SHIFT,
168 			&regs->sdcr1);
169 
170 		if (target_bank == SDRAM_BANK2)
171 			writel(control->cas_latency << FMC_SDCR_CAS_SHIFT
172 				| control->no_banks << FMC_SDCR_NB_SHIFT
173 				| control->memory_width << FMC_SDCR_MWID_SHIFT
174 				| control->no_rows << FMC_SDCR_NR_SHIFT
175 				| control->no_columns << FMC_SDCR_NC_SHIFT,
176 				&regs->sdcr2);
177 
178 		writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
179 			| timing->trp << FMC_SDTR_TRP_SHIFT
180 			| timing->twr << FMC_SDTR_TWR_SHIFT
181 			| timing->trc << FMC_SDTR_TRC_SHIFT
182 			| timing->tras << FMC_SDTR_TRAS_SHIFT
183 			| timing->txsr << FMC_SDTR_TXSR_SHIFT
184 			| timing->tmrd << FMC_SDTR_TMRD_SHIFT,
185 			&regs->sdtr1);
186 
187 		if (target_bank == SDRAM_BANK2)
188 			writel(timing->trcd << FMC_SDTR_TRCD_SHIFT
189 				| timing->trp << FMC_SDTR_TRP_SHIFT
190 				| timing->twr << FMC_SDTR_TWR_SHIFT
191 				| timing->trc << FMC_SDTR_TRC_SHIFT
192 				| timing->tras << FMC_SDTR_TRAS_SHIFT
193 				| timing->txsr << FMC_SDTR_TXSR_SHIFT
194 				| timing->tmrd << FMC_SDTR_TMRD_SHIFT,
195 				&regs->sdtr2);
196 		if (target_bank == SDRAM_BANK1)
197 			ctb = FMC_SDCMR_BANK_1;
198 		else
199 			ctb = FMC_SDCMR_BANK_2;
200 
201 		writel(ctb | FMC_SDCMR_MODE_START_CLOCK, &regs->sdcmr);
202 		udelay(200);	/* 200 us delay, page 10, "Power-Up" */
203 		FMC_BUSY_WAIT(regs);
204 
205 		writel(ctb | FMC_SDCMR_MODE_PRECHARGE, &regs->sdcmr);
206 		udelay(100);
207 		FMC_BUSY_WAIT(regs);
208 
209 		writel((ctb | FMC_SDCMR_MODE_AUTOREFRESH | 7 << FMC_SDCMR_NRFS_SHIFT),
210 		       &regs->sdcmr);
211 		udelay(100);
212 		FMC_BUSY_WAIT(regs);
213 
214 		writel(ctb | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT
215 		       | control->cas_latency << SDRAM_MODE_CAS_SHIFT)
216 		       << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE,
217 		       &regs->sdcmr);
218 		udelay(100);
219 		FMC_BUSY_WAIT(regs);
220 
221 		writel(ctb | FMC_SDCMR_MODE_NORMAL, &regs->sdcmr);
222 		FMC_BUSY_WAIT(regs);
223 
224 		/* Refresh timer */
225 		writel(ref_count << 1, &regs->sdrtr);
226 	}
227 
228 	return 0;
229 }
230 
231 static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
232 {
233 	struct stm32_sdram_params *params = dev_get_platdata(dev);
234 	struct bank_params *bank_params;
235 	ofnode bank_node;
236 	char *bank_name;
237 	u8 bank = 0;
238 
239 	dev_for_each_subnode(bank_node, dev) {
240 		/* extract the bank index from DT */
241 		bank_name = (char *)ofnode_get_name(bank_node);
242 		strsep(&bank_name, "@");
243 		if (!bank_name) {
244 			error("missing sdram bank index");
245 			return -EINVAL;
246 		}
247 
248 		bank_params = &params->bank_params[bank];
249 		strict_strtoul(bank_name, 10,
250 			       (long unsigned int *)&bank_params->target_bank);
251 
252 		if (bank_params->target_bank >= MAX_SDRAM_BANK) {
253 			error("Found bank %d , but only bank 0 and 1 are supported",
254 			      bank_params->target_bank);
255 			return -EINVAL;
256 		}
257 
258 		debug("Find bank %s %u\n", bank_name, bank_params->target_bank);
259 
260 		params->bank_params[bank].sdram_control =
261 			(struct stm32_sdram_control *)
262 			 ofnode_read_u8_array_ptr(bank_node,
263 						  "st,sdram-control",
264 						  sizeof(struct stm32_sdram_control));
265 
266 		if (!params->bank_params[bank].sdram_control) {
267 			error("st,sdram-control not found for %s",
268 			      ofnode_get_name(bank_node));
269 			return -EINVAL;
270 		}
271 
272 
273 		params->bank_params[bank].sdram_timing =
274 			(struct stm32_sdram_timing *)
275 			 ofnode_read_u8_array_ptr(bank_node,
276 						  "st,sdram-timing",
277 						  sizeof(struct stm32_sdram_timing));
278 
279 		if (!params->bank_params[bank].sdram_timing) {
280 			error("st,sdram-timing not found for %s",
281 			      ofnode_get_name(bank_node));
282 			return -EINVAL;
283 		}
284 
285 
286 		bank_params->sdram_ref_count = ofnode_read_u32_default(bank_node,
287 						"st,sdram-refcount", 8196);
288 		bank++;
289 	}
290 
291 	params->no_sdram_banks = bank;
292 	debug("%s, no of banks = %d\n", __func__, params->no_sdram_banks);
293 
294 	return 0;
295 }
296 
297 static int stm32_fmc_probe(struct udevice *dev)
298 {
299 	struct stm32_sdram_params *params = dev_get_platdata(dev);
300 	int ret;
301 	fdt_addr_t addr;
302 
303 	addr = dev_read_addr(dev);
304 	if (addr == FDT_ADDR_T_NONE)
305 		return -EINVAL;
306 
307 	params->base = (struct stm32_fmc_regs *)addr;
308 
309 #ifdef CONFIG_CLK
310 	struct clk clk;
311 
312 	ret = clk_get_by_index(dev, 0, &clk);
313 	if (ret < 0)
314 		return ret;
315 
316 	ret = clk_enable(&clk);
317 
318 	if (ret) {
319 		dev_err(dev, "failed to enable clock\n");
320 		return ret;
321 	}
322 #endif
323 	ret = stm32_sdram_init(dev);
324 	if (ret)
325 		return ret;
326 
327 	return 0;
328 }
329 
330 static int stm32_fmc_get_info(struct udevice *dev, struct ram_info *info)
331 {
332 	return 0;
333 }
334 
335 static struct ram_ops stm32_fmc_ops = {
336 	.get_info = stm32_fmc_get_info,
337 };
338 
339 static const struct udevice_id stm32_fmc_ids[] = {
340 	{ .compatible = "st,stm32-fmc" },
341 	{ }
342 };
343 
344 U_BOOT_DRIVER(stm32_fmc) = {
345 	.name = "stm32_fmc",
346 	.id = UCLASS_RAM,
347 	.of_match = stm32_fmc_ids,
348 	.ops = &stm32_fmc_ops,
349 	.ofdata_to_platdata = stm32_fmc_ofdata_to_platdata,
350 	.probe = stm32_fmc_probe,
351 	.platdata_auto_alloc_size = sizeof(struct stm32_sdram_params),
352 };
353