xref: /openbmc/u-boot/arch/mips/mach-ath79/ar933x/ddr.c (revision 6e87ae1c)
1 /*
2  * Copyright (C) 2015-2016 Wills Wang <wills.wang@live.com>
3  * Based on Atheros LSDK/QSDK
4  *
5  * SPDX-License-Identifier: GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <asm/io.h>
10 #include <asm/addrspace.h>
11 #include <asm/types.h>
12 #include <mach/ar71xx_regs.h>
13 #include <mach/ath79.h>
14 
15 DECLARE_GLOBAL_DATA_PTR;
16 
17 #define DDR_CTRL_UPD_EMR3S      BIT(5)
18 #define DDR_CTRL_UPD_EMR2S      BIT(4)
19 #define DDR_CTRL_PRECHARGE      BIT(3)
20 #define DDR_CTRL_AUTO_REFRESH   BIT(2)
21 #define DDR_CTRL_UPD_EMRS       BIT(1)
22 #define DDR_CTRL_UPD_MRS        BIT(0)
23 
24 #define DDR_REFRESH_EN          BIT(14)
25 #define DDR_REFRESH_M           0x3ff
26 #define DDR_REFRESH(x)          ((x) & 0x3ff)
27 #define DDR_REFRESH_VAL_25M     (DDR_REFRESH_EN | DDR_REFRESH(390))
28 #define DDR_REFRESH_VAL_40M     (DDR_REFRESH_EN | DDR_REFRESH(624))
29 
30 #define DDR_TRAS_S              0
31 #define DDR_TRAS_M              0x1f
32 #define DDR_TRAS(x)             ((x) << DDR_TRAS_S)
33 #define DDR_TRCD_M              0xf
34 #define DDR_TRCD_S              5
35 #define DDR_TRCD(x)             ((x) << DDR_TRCD_S)
36 #define DDR_TRP_M               0xf
37 #define DDR_TRP_S               9
38 #define DDR_TRP(x)              ((x) << DDR_TRP_S)
39 #define DDR_TRRD_M              0xf
40 #define DDR_TRRD_S              13
41 #define DDR_TRRD(x)             ((x) << DDR_TRRD_S)
42 #define DDR_TRFC_M              0x7f
43 #define DDR_TRFC_S              17
44 #define DDR_TRFC(x)             ((x) << DDR_TRFC_S)
45 #define DDR_TMRD_M              0xf
46 #define DDR_TMRD_S              23
47 #define DDR_TMRD(x)             ((x) << DDR_TMRD_S)
48 #define DDR_CAS_L_M             0x17
49 #define DDR_CAS_L_S             27
50 #define DDR_CAS_L(x)            (((x) & DDR_CAS_L_M) << DDR_CAS_L_S)
51 #define DDR_OPEN                BIT(30)
52 #define DDR_CONF_REG_VAL        (DDR_TRAS(16) | DDR_TRCD(6) | \
53 				 DDR_TRP(6) | DDR_TRRD(4) | \
54 				 DDR_TRFC(30) | DDR_TMRD(15) | \
55 				 DDR_CAS_L(7) | DDR_OPEN)
56 
57 #define DDR_BURST_LEN_S         0
58 #define DDR_BURST_LEN_M         0xf
59 #define DDR_BURST_LEN(x)        ((x) << DDR_BURST_LEN_S)
60 #define DDR_BURST_TYPE          BIT(4)
61 #define DDR_CNTL_OE_EN          BIT(5)
62 #define DDR_PHASE_SEL           BIT(6)
63 #define DDR_CKE                 BIT(7)
64 #define DDR_TWR_S               8
65 #define DDR_TWR_M               0xf
66 #define DDR_TWR(x)              ((x) << DDR_TWR_S)
67 #define DDR_TRTW_S              12
68 #define DDR_TRTW_M              0x1f
69 #define DDR_TRTW(x)             ((x) << DDR_TRTW_S)
70 #define DDR_TRTP_S              17
71 #define DDR_TRTP_M              0xf
72 #define DDR_TRTP(x)             ((x) << DDR_TRTP_S)
73 #define DDR_TWTR_S              21
74 #define DDR_TWTR_M              0x1f
75 #define DDR_TWTR(x)             ((x) << DDR_TWTR_S)
76 #define DDR_G_OPEN_L_S          26
77 #define DDR_G_OPEN_L_M          0xf
78 #define DDR_G_OPEN_L(x)         ((x) << DDR_G_OPEN_L_S)
79 #define DDR_HALF_WIDTH_LOW      BIT(31)
80 #define DDR_CONF2_REG_VAL       (DDR_BURST_LEN(8) | DDR_CNTL_OE_EN | \
81 				 DDR_CKE | DDR_TWR(6) | DDR_TRTW(14) | \
82 				 DDR_TRTP(8) | DDR_TWTR(14) | \
83 				 DDR_G_OPEN_L(7) | DDR_HALF_WIDTH_LOW)
84 
85 #define DDR2_CONF_TWL_S         10
86 #define DDR2_CONF_TWL_M         0xf
87 #define DDR2_CONF_TWL(x)        (((x) & DDR2_CONF_TWL_M) << DDR2_CONF_TWL_S)
88 #define DDR2_CONF_ODT           BIT(9)
89 #define DDR2_CONF_TFAW_S        2
90 #define DDR2_CONF_TFAW_M        0x3f
91 #define DDR2_CONF_TFAW(x)       (((x) & DDR2_CONF_TFAW_M) << DDR2_CONF_TFAW_S)
92 #define DDR2_CONF_EN            BIT(0)
93 #define DDR2_CONF_VAL           (DDR2_CONF_TWL(2) | DDR2_CONF_ODT | \
94 				 DDR2_CONF_TFAW(22) | DDR2_CONF_EN)
95 
96 #define DDR1_EXT_MODE_VAL       0x02
97 #define DDR2_EXT_MODE_VAL       0x402
98 #define DDR2_EXT_MODE_OCD_VAL   0x382
99 #define DDR1_MODE_DLL_VAL       0x133
100 #define DDR2_MODE_DLL_VAL       0x100
101 #define DDR1_MODE_VAL           0x33
102 #define DDR2_MODE_VAL           0xa33
103 #define DDR_TAP_VAL0            0x08
104 #define DDR_TAP_VAL1            0x09
105 
106 void ddr_init(void)
107 {
108 	void __iomem *regs;
109 	u32 val;
110 
111 	regs = map_physmem(AR71XX_DDR_CTRL_BASE, AR71XX_DDR_CTRL_SIZE,
112 			   MAP_NOCACHE);
113 
114 	writel(DDR_CONF_REG_VAL, regs + AR71XX_DDR_REG_CONFIG);
115 	writel(DDR_CONF2_REG_VAL, regs + AR71XX_DDR_REG_CONFIG2);
116 
117 	val = ath79_get_bootstrap();
118 	if (val & AR933X_BOOTSTRAP_DDR2) {
119 		/* AHB maximum timeout */
120 		writel(0xfffff, regs + AR933X_DDR_REG_TIMEOUT_MAX);
121 
122 		/* Enable DDR2 */
123 		writel(DDR2_CONF_VAL, regs + AR933X_DDR_REG_DDR2_CONFIG);
124 
125 		/* Precharge All */
126 		writel(DDR_CTRL_PRECHARGE, regs + AR71XX_DDR_REG_CONTROL);
127 
128 		/* Disable High Temperature Self-Refresh, Full Array */
129 		writel(0x00, regs + AR933X_DDR_REG_EMR2);
130 
131 		/* Extended Mode Register 2 Set (EMR2S) */
132 		writel(DDR_CTRL_UPD_EMR2S, regs + AR71XX_DDR_REG_CONTROL);
133 
134 		writel(0x00, regs + AR933X_DDR_REG_EMR3);
135 
136 		/* Extended Mode Register 3 Set (EMR3S) */
137 		writel(DDR_CTRL_UPD_EMR3S, regs + AR71XX_DDR_REG_CONTROL);
138 
139 		/* Enable DLL,  Full strength, ODT Disabled */
140 		writel(0x00, regs + AR71XX_DDR_REG_EMR);
141 
142 		/* Extended Mode Register Set (EMRS) */
143 		writel(DDR_CTRL_UPD_EMRS, regs + AR71XX_DDR_REG_CONTROL);
144 
145 		/* Reset DLL */
146 		writel(DDR2_MODE_DLL_VAL, regs + AR71XX_DDR_REG_MODE);
147 
148 		/* Mode Register Set (MRS) */
149 		writel(DDR_CTRL_UPD_MRS, regs + AR71XX_DDR_REG_CONTROL);
150 
151 		/* Precharge All */
152 		writel(DDR_CTRL_PRECHARGE, regs + AR71XX_DDR_REG_CONTROL);
153 
154 		/* Auto Refresh */
155 		writel(DDR_CTRL_AUTO_REFRESH, regs + AR71XX_DDR_REG_CONTROL);
156 		writel(DDR_CTRL_AUTO_REFRESH, regs + AR71XX_DDR_REG_CONTROL);
157 
158 		/* Write recovery (WR) 6 clock, CAS Latency 3, Burst Length 8 */
159 		writel(DDR2_MODE_VAL, regs + AR71XX_DDR_REG_MODE);
160 		/* Mode Register Set (MRS) */
161 		writel(DDR_CTRL_UPD_MRS, regs + AR71XX_DDR_REG_CONTROL);
162 
163 		/* Enable OCD defaults, Enable DLL, Reduced Drive Strength */
164 		writel(DDR2_EXT_MODE_OCD_VAL, regs + AR71XX_DDR_REG_EMR);
165 
166 		/* Extended Mode Register Set (EMRS) */
167 		writel(DDR_CTRL_UPD_EMRS, regs + AR71XX_DDR_REG_CONTROL);
168 
169 		/* OCD exit, Enable DLL, Enable /DQS, Reduced Drive Strength */
170 		writel(DDR2_EXT_MODE_VAL, regs + AR71XX_DDR_REG_EMR);
171 		/* Extended Mode Register Set (EMRS) */
172 		writel(DDR_CTRL_UPD_EMRS, regs + AR71XX_DDR_REG_CONTROL);
173 
174 		/* Refresh time control */
175 		if (val & AR933X_BOOTSTRAP_REF_CLK_40)
176 			writel(DDR_REFRESH_VAL_40M, regs +
177 			       AR71XX_DDR_REG_REFRESH);
178 		else
179 			writel(DDR_REFRESH_VAL_25M, regs +
180 			       AR71XX_DDR_REG_REFRESH);
181 
182 		/* DQS 0 Tap Control */
183 		writel(DDR_TAP_VAL0, regs + AR71XX_DDR_REG_TAP_CTRL0);
184 
185 		/* DQS 1 Tap Control */
186 		writel(DDR_TAP_VAL1, regs + AR71XX_DDR_REG_TAP_CTRL1);
187 
188 		/* For 16-bit DDR */
189 		writel(0xff, regs + AR71XX_DDR_REG_RD_CYCLE);
190 	} else {
191 		/* AHB maximum timeout */
192 		writel(0xfffff, regs + AR933X_DDR_REG_TIMEOUT_MAX);
193 
194 		/* Precharge All */
195 		writel(DDR_CTRL_PRECHARGE, regs + AR71XX_DDR_REG_CONTROL);
196 
197 		/* Reset DLL, Burst Length 8, CAS Latency 3 */
198 		writel(DDR1_MODE_DLL_VAL, regs + AR71XX_DDR_REG_MODE);
199 
200 		/* Forces an MRS update cycle in DDR */
201 		writel(DDR_CTRL_UPD_MRS, regs + AR71XX_DDR_REG_CONTROL);
202 
203 		/* Enable DLL, Full strength */
204 		writel(DDR1_EXT_MODE_VAL, regs + AR71XX_DDR_REG_EMR);
205 
206 		/* Extended Mode Register Set (EMRS) */
207 		writel(DDR_CTRL_UPD_EMRS, regs + AR71XX_DDR_REG_CONTROL);
208 
209 		/* Precharge All */
210 		writel(DDR_CTRL_PRECHARGE, regs + AR71XX_DDR_REG_CONTROL);
211 
212 		/* Normal DLL, Burst Length 8, CAS Latency 3 */
213 		writel(DDR1_MODE_VAL, regs + AR71XX_DDR_REG_MODE);
214 
215 		/* Mode Register Set (MRS) */
216 		writel(DDR_CTRL_UPD_MRS, regs + AR71XX_DDR_REG_CONTROL);
217 
218 		/* Refresh time control */
219 		if (val & AR933X_BOOTSTRAP_REF_CLK_40)
220 			writel(DDR_REFRESH_VAL_40M, regs +
221 			       AR71XX_DDR_REG_REFRESH);
222 		else
223 			writel(DDR_REFRESH_VAL_25M, regs +
224 			       AR71XX_DDR_REG_REFRESH);
225 
226 		/* DQS 0 Tap Control */
227 		writel(DDR_TAP_VAL0, regs + AR71XX_DDR_REG_TAP_CTRL0);
228 
229 		/* DQS 1 Tap Control */
230 		writel(DDR_TAP_VAL1, regs + AR71XX_DDR_REG_TAP_CTRL1);
231 
232 		/* For 16-bit DDR */
233 		writel(0xff, regs + AR71XX_DDR_REG_RD_CYCLE);
234 	}
235 }
236 
237 void ddr_tap_tuning(void)
238 {
239 	void __iomem *regs;
240 	u32 *addr_k0, *addr_k1, *addr;
241 	u32 val, tap, upper, lower;
242 	int i, j, dir, err, done;
243 
244 	regs = map_physmem(AR71XX_DDR_CTRL_BASE, AR71XX_DDR_CTRL_SIZE,
245 			   MAP_NOCACHE);
246 
247 	/* Init memory pattern */
248 	addr = (void *)CKSEG0ADDR(0x2000);
249 	for (i = 0; i < 256; i++) {
250 		val = 0;
251 		for (j = 0; j < 8; j++) {
252 			if (i & (1 << j)) {
253 				if (j % 2)
254 					val |= 0xffff0000;
255 				else
256 					val |= 0x0000ffff;
257 			}
258 
259 			if (j % 2) {
260 				*addr++ = val;
261 				val = 0;
262 			}
263 		}
264 	}
265 
266 	err = 0;
267 	done = 0;
268 	dir = 1;
269 	tap = readl(regs + AR71XX_DDR_REG_TAP_CTRL0);
270 	val = tap;
271 	upper = tap;
272 	lower = tap;
273 	while (!done) {
274 		err = 0;
275 
276 		/* Update new DDR tap value */
277 		writel(val, regs + AR71XX_DDR_REG_TAP_CTRL0);
278 		writel(val, regs + AR71XX_DDR_REG_TAP_CTRL1);
279 
280 		/* Compare DDR with cache */
281 		for (i = 0; i < 2; i++) {
282 			addr_k1 = (void *)CKSEG1ADDR(0x2000);
283 			addr_k0 = (void *)CKSEG0ADDR(0x2000);
284 			addr = (void *)CKSEG0ADDR(0x3000);
285 
286 			while (addr_k0 < addr) {
287 				if (*addr_k1++ != *addr_k0++) {
288 					err = 1;
289 					break;
290 				}
291 			}
292 
293 			if (err)
294 				break;
295 		}
296 
297 		if (err) {
298 			/* Save upper/lower threshold if error  */
299 			if (dir) {
300 				dir = 0;
301 				val--;
302 				upper = val;
303 				val = tap;
304 			} else {
305 				val++;
306 				lower = val;
307 				done = 1;
308 			}
309 		} else {
310 			/* Try the next value until limitation */
311 			if (dir) {
312 				if (val < 0x20) {
313 					val++;
314 				} else {
315 					dir = 0;
316 					upper = val;
317 					val = tap;
318 				}
319 			} else {
320 				if (!val) {
321 					lower = val;
322 					done = 1;
323 				} else {
324 					val--;
325 				}
326 			}
327 		}
328 	}
329 
330 	/* compute an intermediate value and write back */
331 	val = (upper + lower) / 2;
332 	writel(val, regs + AR71XX_DDR_REG_TAP_CTRL0);
333 	val++;
334 	writel(val, regs + AR71XX_DDR_REG_TAP_CTRL1);
335 }
336