xref: /rk3399_rockchip-uboot/drivers/ram/stm32_sdram.c (revision 1421e0a375334d8ff2f996a95dccbc5e9a1a02f0)
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 struct stm32_sdram_params {
121 	struct stm32_fmc_regs *base;
122 	u8 no_sdram_banks;
123 	struct stm32_sdram_control sdram_control;
124 	struct stm32_sdram_timing sdram_timing;
125 	u32 sdram_ref_count;
126 };
127 
128 #define SDRAM_MODE_BL_SHIFT	0
129 #define SDRAM_MODE_CAS_SHIFT	4
130 #define SDRAM_MODE_BL		0
131 
132 int stm32_sdram_init(struct udevice *dev)
133 {
134 	struct stm32_sdram_params *params = dev_get_platdata(dev);
135 	struct stm32_fmc_regs *regs = params->base;
136 
137 	writel(params->sdram_control.sdclk << FMC_SDCR_SDCLK_SHIFT
138 		| params->sdram_control.cas_latency << FMC_SDCR_CAS_SHIFT
139 		| params->sdram_control.no_banks << FMC_SDCR_NB_SHIFT
140 		| params->sdram_control.memory_width << FMC_SDCR_MWID_SHIFT
141 		| params->sdram_control.no_rows << FMC_SDCR_NR_SHIFT
142 		| params->sdram_control.no_columns << FMC_SDCR_NC_SHIFT
143 		| params->sdram_control.rd_pipe_delay << FMC_SDCR_RPIPE_SHIFT
144 		| params->sdram_control.rd_burst << FMC_SDCR_RBURST_SHIFT,
145 		&regs->sdcr1);
146 
147 	writel(params->sdram_timing.trcd << FMC_SDTR_TRCD_SHIFT
148 		| params->sdram_timing.trp << FMC_SDTR_TRP_SHIFT
149 		| params->sdram_timing.twr << FMC_SDTR_TWR_SHIFT
150 		| params->sdram_timing.trc << FMC_SDTR_TRC_SHIFT
151 		| params->sdram_timing.tras << FMC_SDTR_TRAS_SHIFT
152 		| params->sdram_timing.txsr << FMC_SDTR_TXSR_SHIFT
153 		| params->sdram_timing.tmrd << FMC_SDTR_TMRD_SHIFT,
154 		&regs->sdtr1);
155 
156 	writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_START_CLOCK,
157 	       &regs->sdcmr);
158 	udelay(200);	/* 200 us delay, page 10, "Power-Up" */
159 	FMC_BUSY_WAIT(regs);
160 
161 	writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_PRECHARGE,
162 	       &regs->sdcmr);
163 	udelay(100);
164 	FMC_BUSY_WAIT(regs);
165 
166 	writel((FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_AUTOREFRESH
167 		| 7 << FMC_SDCMR_NRFS_SHIFT), &regs->sdcmr);
168 	udelay(100);
169 	FMC_BUSY_WAIT(regs);
170 
171 	writel(FMC_SDCMR_BANK_1 | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT
172 	       | params->sdram_control.cas_latency << SDRAM_MODE_CAS_SHIFT)
173 	       << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE,
174 	       &regs->sdcmr);
175 	udelay(100);
176 	FMC_BUSY_WAIT(regs);
177 
178 	writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_NORMAL,
179 	       &regs->sdcmr);
180 	FMC_BUSY_WAIT(regs);
181 
182 	/* Refresh timer */
183 	writel((params->sdram_ref_count) << 1, &regs->sdrtr);
184 
185 	return 0;
186 }
187 
188 static int stm32_fmc_ofdata_to_platdata(struct udevice *dev)
189 {
190 	int ret;
191 	int node = dev_of_offset(dev);
192 	const void *blob = gd->fdt_blob;
193 	struct stm32_sdram_params *params = dev_get_platdata(dev);
194 
195 	params->no_sdram_banks = fdtdec_get_uint(blob, node, "mr-nbanks", 1);
196 	debug("%s, no of banks = %d\n", __func__, params->no_sdram_banks);
197 
198 	fdt_for_each_subnode(node, blob, node) {
199 		ret = fdtdec_get_byte_array(blob, node, "st,sdram-control",
200 					    (u8 *)&params->sdram_control,
201 					    sizeof(params->sdram_control));
202 		if (ret)
203 			return ret;
204 		ret = fdtdec_get_byte_array(blob, node, "st,sdram-timing",
205 					    (u8 *)&params->sdram_timing,
206 					    sizeof(params->sdram_timing));
207 		if (ret)
208 			return ret;
209 
210 		params->sdram_ref_count = fdtdec_get_int(blob, node,
211 						"st,sdram-refcount", 8196);
212 	}
213 
214 	return 0;
215 }
216 
217 static int stm32_fmc_probe(struct udevice *dev)
218 {
219 	struct stm32_sdram_params *params = dev_get_platdata(dev);
220 	int ret;
221 	fdt_addr_t addr;
222 
223 	addr = dev_read_addr(dev);
224 	if (addr == FDT_ADDR_T_NONE)
225 		return -EINVAL;
226 
227 	params->base = (struct stm32_fmc_regs *)addr;
228 
229 #ifdef CONFIG_CLK
230 	struct clk clk;
231 
232 	ret = clk_get_by_index(dev, 0, &clk);
233 	if (ret < 0)
234 		return ret;
235 
236 	ret = clk_enable(&clk);
237 
238 	if (ret) {
239 		dev_err(dev, "failed to enable clock\n");
240 		return ret;
241 	}
242 #endif
243 	ret = stm32_sdram_init(dev);
244 	if (ret)
245 		return ret;
246 
247 	return 0;
248 }
249 
250 static int stm32_fmc_get_info(struct udevice *dev, struct ram_info *info)
251 {
252 	return 0;
253 }
254 
255 static struct ram_ops stm32_fmc_ops = {
256 	.get_info = stm32_fmc_get_info,
257 };
258 
259 static const struct udevice_id stm32_fmc_ids[] = {
260 	{ .compatible = "st,stm32-fmc" },
261 	{ }
262 };
263 
264 U_BOOT_DRIVER(stm32_fmc) = {
265 	.name = "stm32_fmc",
266 	.id = UCLASS_RAM,
267 	.of_match = stm32_fmc_ids,
268 	.ops = &stm32_fmc_ops,
269 	.ofdata_to_platdata = stm32_fmc_ofdata_to_platdata,
270 	.probe = stm32_fmc_probe,
271 	.platdata_auto_alloc_size = sizeof(struct stm32_sdram_params),
272 };
273