1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2012-2020  ASPEED Technology Inc.
4  *
5  * Copyright 2016 Google, Inc
6  */
7 
8 #include <common.h>
9 #include <clk.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <ram.h>
13 #include <regmap.h>
14 #include <reset.h>
15 #include <asm/io.h>
16 #include <asm/arch/scu_ast2500.h>
17 #include <asm/arch/sdram_ast2500.h>
18 #include <asm/arch/wdt.h>
19 #include <linux/err.h>
20 #include <linux/kernel.h>
21 #include <dt-bindings/clock/ast2500-scu.h>
22 
23 /* These configuration parameters are taken from Aspeed SDK */
24 #define DDR4_MR46_MODE		0x08000000
25 #define DDR4_MR5_MODE		0x400
26 #define DDR4_MR13_MODE		0x101
27 #define DDR4_MR02_MODE		0x410
28 #define DDR4_TRFC		0x45457188
29 
30 #define PHY_CFG_SIZE		15
31 
32 static const u32 ddr4_ac_timing[3] = {0x63604e37, 0xe97afa99, 0x00019000};
33 static const struct {
34 	u32 index[PHY_CFG_SIZE];
35 	u32 value[PHY_CFG_SIZE];
36 } ddr4_phy_config = {
37 	.index = {0, 1, 3, 4, 5, 56, 57, 58, 59, 60, 61, 62, 36, 49, 50},
38 	.value = {
39 		0x42492aae, 0x09002000, 0x55e00b0b, 0x20000000, 0x24,
40 		0x03002900, 0x0e0000a0, 0x000e001c, 0x35b8c106, 0x08080607,
41 		0x9b000900, 0x0e400a00, 0x00100008, 0x3c183c3c, 0x00631e0e,
42 	},
43 };
44 
45 #define SDRAM_MAX_SIZE		(1024 * 1024 * 1024)
46 #define SDRAM_MIN_SIZE		(128 * 1024 * 1024)
47 
48 DECLARE_GLOBAL_DATA_PTR;
49 
50 /*
51  * Bandwidth configuration parameters for different SDRAM requests.
52  * These are hardcoded settings taken from Aspeed SDK.
53  */
54 static const u32 ddr_max_grant_params[4] = {
55 	0x88448844, 0x24422288, 0x22222222, 0x22222222
56 };
57 
58 /*
59  * These registers are not documented by Aspeed at all.
60  * All writes and reads are taken pretty much as is from SDK.
61  */
62 struct ast2500_ddr_phy {
63 	u32 phy[117];
64 };
65 
66 struct dram_info {
67 	struct ram_info info;
68 	struct clk ddr_clk;
69 	struct ast2500_sdrammc_regs *regs;
70 	struct ast2500_scu *scu;
71 	struct ast2500_ddr_phy *phy;
72 	ulong clock_rate;
73 };
74 
ast2500_sdrammc_init_phy(struct ast2500_ddr_phy * phy)75 static int ast2500_sdrammc_init_phy(struct ast2500_ddr_phy *phy)
76 {
77 	writel(0, &phy->phy[2]);
78 	writel(0, &phy->phy[6]);
79 	writel(0, &phy->phy[8]);
80 	writel(0, &phy->phy[10]);
81 	writel(0, &phy->phy[12]);
82 	writel(0, &phy->phy[42]);
83 	writel(0, &phy->phy[44]);
84 
85 	writel(0x86000000, &phy->phy[16]);
86 	writel(0x00008600, &phy->phy[17]);
87 	writel(0x80000000, &phy->phy[18]);
88 	writel(0x80808080, &phy->phy[19]);
89 
90 	return 0;
91 }
92 
ast2500_ddr_phy_init_process(struct dram_info * info)93 static void ast2500_ddr_phy_init_process(struct dram_info *info)
94 {
95 	struct ast2500_sdrammc_regs *regs = info->regs;
96 
97 	writel(0, &regs->phy_ctrl[0]);
98 	writel(0x4040, &info->phy->phy[51]);
99 
100 	writel(SDRAM_PHYCTRL0_NRST | SDRAM_PHYCTRL0_INIT, &regs->phy_ctrl[0]);
101 	while ((readl(&regs->phy_ctrl[0]) & SDRAM_PHYCTRL0_INIT))
102 		;
103 	writel(SDRAM_PHYCTRL0_NRST | SDRAM_PHYCTRL0_AUTO_UPDATE,
104 	       &regs->phy_ctrl[0]);
105 }
106 
ast2500_sdrammc_set_vref(struct dram_info * info,u32 vref)107 static void ast2500_sdrammc_set_vref(struct dram_info *info, u32 vref)
108 {
109 	writel(0, &info->regs->phy_ctrl[0]);
110 	writel((vref << 8) | 0x6, &info->phy->phy[48]);
111 	ast2500_ddr_phy_init_process(info);
112 }
113 
ast2500_ddr_cbr_test(struct dram_info * info)114 static int ast2500_ddr_cbr_test(struct dram_info *info)
115 {
116 	struct ast2500_sdrammc_regs *regs = info->regs;
117 	int i;
118 	const u32 test_params = SDRAM_TEST_EN
119 			| SDRAM_TEST_ERRSTOP
120 			| SDRAM_TEST_TWO_MODES;
121 	int ret = 0;
122 
123 	writel((1 << SDRAM_REFRESH_CYCLES_SHIFT) |
124 	       (0x5c << SDRAM_REFRESH_PERIOD_SHIFT), &regs->refresh_timing);
125 	writel((0xfff << SDRAM_TEST_LEN_SHIFT), &regs->test_addr);
126 	writel(0xff00ff00, &regs->test_init_val);
127 	writel(SDRAM_TEST_EN | (SDRAM_TEST_MODE_RW << SDRAM_TEST_MODE_SHIFT) |
128 	       SDRAM_TEST_ERRSTOP, &regs->ecc_test_ctrl);
129 
130 	while (!(readl(&regs->ecc_test_ctrl) & SDRAM_TEST_DONE))
131 		;
132 
133 	if (readl(&regs->ecc_test_ctrl) & SDRAM_TEST_FAIL) {
134 		ret = -EIO;
135 	} else {
136 		for (i = 0; i <= SDRAM_TEST_GEN_MODE_MASK; ++i) {
137 			writel((i << SDRAM_TEST_GEN_MODE_SHIFT) | test_params,
138 			       &regs->ecc_test_ctrl);
139 			while (!(readl(&regs->ecc_test_ctrl) & SDRAM_TEST_DONE))
140 				;
141 			if (readl(&regs->ecc_test_ctrl) & SDRAM_TEST_FAIL) {
142 				ret = -EIO;
143 				break;
144 			}
145 		}
146 	}
147 
148 	writel(0, &regs->refresh_timing);
149 	writel(0, &regs->ecc_test_ctrl);
150 
151 	return ret;
152 }
153 
ast2500_sdrammc_ddr4_calibrate_vref(struct dram_info * info)154 static int ast2500_sdrammc_ddr4_calibrate_vref(struct dram_info *info)
155 {
156 	int i;
157 	int vref_min = 0xff;
158 	int vref_max = 0;
159 	int range_size = 0;
160 
161 	for (i = 1; i < 0x40; ++i) {
162 		int res;
163 
164 		ast2500_sdrammc_set_vref(info, i);
165 		res = ast2500_ddr_cbr_test(info);
166 		if (res < 0) {
167 			if (range_size > 0)
168 				break;
169 		} else {
170 			++range_size;
171 			vref_min = min(vref_min, i);
172 			vref_max = max(vref_max, i);
173 		}
174 	}
175 
176 	/* Pick average setting */
177 	ast2500_sdrammc_set_vref(info, (vref_min + vref_max + 1) / 2);
178 
179 	return 0;
180 }
181 
ast2500_sdrammc_get_vga_mem_size(struct dram_info * info)182 static size_t ast2500_sdrammc_get_vga_mem_size(struct dram_info *info)
183 {
184 	size_t vga_mem_size_base = 8 * 1024 * 1024;
185 	u32 vga_hwconf = (readl(&info->scu->hwstrap) & SCU_HWSTRAP_VGAMEM_MASK)
186 	    >> SCU_HWSTRAP_VGAMEM_SHIFT;
187 
188 	return vga_mem_size_base << vga_hwconf;
189 }
190 
191 /*
192  * Find out RAM size and save it in dram_info
193  *
194  * The procedure is taken from Aspeed SDK
195  */
ast2500_sdrammc_calc_size(struct dram_info * info)196 static void ast2500_sdrammc_calc_size(struct dram_info *info)
197 {
198 	/* The controller supports 128/256/512/1024 MB ram */
199 	size_t ram_size = SDRAM_MIN_SIZE;
200 	const int write_test_offset = 0x100000;
201 	u32 test_pattern = 0xdeadbeef;
202 	u32 cap_param = SDRAM_CONF_CAP_1024M;
203 	u32 refresh_timing_param = DDR4_TRFC;
204 	const u32 write_addr_base = CONFIG_SYS_SDRAM_BASE + write_test_offset;
205 
206 	for (ram_size = SDRAM_MAX_SIZE; ram_size > SDRAM_MIN_SIZE;
207 	     ram_size >>= 1) {
208 		writel(test_pattern, write_addr_base + (ram_size >> 1));
209 		test_pattern = (test_pattern >> 4) | (test_pattern << 28);
210 	}
211 
212 	/* One last write to overwrite all wrapped values */
213 	writel(test_pattern, write_addr_base);
214 
215 	/* Reset the pattern and see which value was really written */
216 	test_pattern = 0xdeadbeef;
217 	for (ram_size = SDRAM_MAX_SIZE; ram_size > SDRAM_MIN_SIZE;
218 	     ram_size >>= 1) {
219 		if (readl(write_addr_base + (ram_size >> 1)) == test_pattern)
220 			break;
221 
222 		--cap_param;
223 		refresh_timing_param >>= 8;
224 		test_pattern = (test_pattern >> 4) | (test_pattern << 28);
225 	}
226 
227 	clrsetbits_le32(&info->regs->ac_timing[1],
228 			(SDRAM_AC_TRFC_MASK << SDRAM_AC_TRFC_SHIFT),
229 			((refresh_timing_param & SDRAM_AC_TRFC_MASK)
230 			 << SDRAM_AC_TRFC_SHIFT));
231 
232 	info->info.base = CONFIG_SYS_SDRAM_BASE;
233 	info->info.size = ram_size - ast2500_sdrammc_get_vga_mem_size(info);
234 	clrsetbits_le32(&info->regs->config,
235 			(SDRAM_CONF_CAP_MASK << SDRAM_CONF_CAP_SHIFT),
236 			((cap_param & SDRAM_CONF_CAP_MASK)
237 			 << SDRAM_CONF_CAP_SHIFT));
238 }
239 
ast2500_sdrammc_init_ddr4(struct dram_info * info)240 static int ast2500_sdrammc_init_ddr4(struct dram_info *info)
241 {
242 	int i;
243 	const u32 power_control = SDRAM_PCR_CKE_EN
244 	    | (1 << SDRAM_PCR_CKE_DELAY_SHIFT)
245 	    | (2 << SDRAM_PCR_TCKE_PW_SHIFT)
246 	    | SDRAM_PCR_RESETN_DIS
247 	    | SDRAM_PCR_RGAP_CTRL_EN | SDRAM_PCR_ODT_EN | SDRAM_PCR_ODT_EXT_EN;
248 	const u32 conf = (SDRAM_CONF_CAP_1024M << SDRAM_CONF_CAP_SHIFT)
249 #ifdef CONFIG_DUALX8_RAM
250 	    | SDRAM_CONF_DUALX8
251 #endif
252 	    | SDRAM_CONF_SCRAMBLE | SDRAM_CONF_SCRAMBLE_PAT2 | SDRAM_CONF_DDR4;
253 	int ret;
254 
255 	writel(conf, &info->regs->config);
256 	for (i = 0; i < ARRAY_SIZE(ddr4_ac_timing); ++i)
257 		writel(ddr4_ac_timing[i], &info->regs->ac_timing[i]);
258 
259 	writel(DDR4_MR46_MODE, &info->regs->mr46_mode_setting);
260 	writel(DDR4_MR5_MODE, &info->regs->mr5_mode_setting);
261 	writel(DDR4_MR02_MODE, &info->regs->mr02_mode_setting);
262 	writel(DDR4_MR13_MODE, &info->regs->mr13_mode_setting);
263 
264 	for (i = 0; i < PHY_CFG_SIZE; ++i) {
265 		writel(ddr4_phy_config.value[i],
266 		       &info->phy->phy[ddr4_phy_config.index[i]]);
267 	}
268 
269 	writel(power_control, &info->regs->power_control);
270 
271 	ast2500_ddr_phy_init_process(info);
272 
273 	ret = ast2500_sdrammc_ddr4_calibrate_vref(info);
274 	if (ret < 0) {
275 		debug("Vref calibration failed!\n");
276 		return ret;
277 	}
278 
279 	writel((1 << SDRAM_REFRESH_CYCLES_SHIFT)
280 	       | SDRAM_REFRESH_ZQCS_EN | (0x2f << SDRAM_REFRESH_PERIOD_SHIFT),
281 	       &info->regs->refresh_timing);
282 
283 	setbits_le32(&info->regs->power_control,
284 		     SDRAM_PCR_AUTOPWRDN_EN | SDRAM_PCR_ODT_AUTO_ON);
285 
286 	ast2500_sdrammc_calc_size(info);
287 
288 	setbits_le32(&info->regs->config, SDRAM_CONF_CACHE_INIT_EN);
289 	while (!(readl(&info->regs->config) & SDRAM_CONF_CACHE_INIT_DONE))
290 		;
291 	setbits_le32(&info->regs->config, SDRAM_CONF_CACHE_EN);
292 
293 	writel(SDRAM_MISC_DDR4_TREFRESH, &info->regs->misc_control);
294 
295 	/* Enable all requests except video & display */
296 	writel(SDRAM_REQ_USB20_EHCI1
297 	       | SDRAM_REQ_USB20_EHCI2
298 	       | SDRAM_REQ_CPU
299 	       | SDRAM_REQ_AHB2
300 	       | SDRAM_REQ_AHB
301 	       | SDRAM_REQ_MAC0
302 	       | SDRAM_REQ_MAC1
303 	       | SDRAM_REQ_PCIE
304 	       | SDRAM_REQ_XDMA
305 	       | SDRAM_REQ_ENCRYPTION
306 	       | SDRAM_REQ_VIDEO_FLAG
307 	       | SDRAM_REQ_VIDEO_LOW_PRI_WRITE
308 	       | SDRAM_REQ_2D_RW
309 	       | SDRAM_REQ_MEMCHECK, &info->regs->req_limit_mask);
310 
311 	return 0;
312 }
313 
ast2500_sdrammc_unlock(struct dram_info * info)314 static void ast2500_sdrammc_unlock(struct dram_info *info)
315 {
316 	writel(SDRAM_UNLOCK_KEY, &info->regs->protection_key);
317 	while (!readl(&info->regs->protection_key))
318 		;
319 }
320 
ast2500_sdrammc_lock(struct dram_info * info)321 static void ast2500_sdrammc_lock(struct dram_info *info)
322 {
323 	writel(~SDRAM_UNLOCK_KEY, &info->regs->protection_key);
324 	while (readl(&info->regs->protection_key))
325 		;
326 }
327 
ast2500_sdrammc_probe(struct udevice * dev)328 static int ast2500_sdrammc_probe(struct udevice *dev)
329 {
330 	struct reset_ctl reset_ctl;
331 	struct dram_info *priv = (struct dram_info *)dev_get_priv(dev);
332 	struct ast2500_sdrammc_regs *regs = priv->regs;
333 	int i;
334 	int ret = clk_get_by_index(dev, 0, &priv->ddr_clk);
335 
336 	if (ret) {
337 		debug("DDR:No CLK\n");
338 		return ret;
339 	}
340 
341 	priv->scu = ast_get_scu();
342 	if (IS_ERR(priv->scu)) {
343 		debug("%s(): can't get SCU\n", __func__);
344 		return PTR_ERR(priv->scu);
345 	}
346 
347 	clk_set_rate(&priv->ddr_clk, priv->clock_rate);
348 	ret = reset_get_by_index(dev, 0, &reset_ctl);
349 	if (ret) {
350 		debug("%s(): Failed to get reset signal\n", __func__);
351 		return ret;
352 	}
353 
354 	ret = reset_assert(&reset_ctl);
355 	if (ret) {
356 		debug("%s(): SDRAM reset failed: %u\n", __func__, ret);
357 		return ret;
358 	}
359 
360 	ast2500_sdrammc_unlock(priv);
361 
362 	writel(SDRAM_PCR_MREQI_DIS | SDRAM_PCR_RESETN_DIS,
363 	       &regs->power_control);
364 	writel(SDRAM_VIDEO_UNLOCK_KEY, &regs->gm_protection_key);
365 
366 	/* Mask all requests except CPU and AHB during PHY init */
367 	writel(~(SDRAM_REQ_CPU | SDRAM_REQ_AHB), &regs->req_limit_mask);
368 
369 	for (i = 0; i < ARRAY_SIZE(ddr_max_grant_params); ++i)
370 		writel(ddr_max_grant_params[i], &regs->max_grant_len[i]);
371 
372 	setbits_le32(&regs->intr_ctrl, SDRAM_ICR_RESET_ALL);
373 
374 	ast2500_sdrammc_init_phy(priv->phy);
375 	if (readl(&priv->scu->hwstrap) & SCU_HWSTRAP_DDR4) {
376 		ast2500_sdrammc_init_ddr4(priv);
377 	} else {
378 		debug("Unsupported DRAM3\n");
379 		return -EINVAL;
380 	}
381 
382 	clrbits_le32(&regs->intr_ctrl, SDRAM_ICR_RESET_ALL);
383 	ast2500_sdrammc_lock(priv);
384 
385 	return 0;
386 }
387 
ast2500_sdrammc_ofdata_to_platdata(struct udevice * dev)388 static int ast2500_sdrammc_ofdata_to_platdata(struct udevice *dev)
389 {
390 	struct dram_info *priv = dev_get_priv(dev);
391 	struct regmap *map;
392 	int ret;
393 
394 	ret = regmap_init_mem(dev_ofnode(dev), &map);
395 	if (ret)
396 		return ret;
397 
398 	priv->regs = regmap_get_range(map, 0);
399 	priv->phy = regmap_get_range(map, 1);
400 
401 	priv->clock_rate = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
402 					  "clock-frequency", 0);
403 
404 	if (!priv->clock_rate) {
405 		debug("DDR Clock Rate not defined\n");
406 		return -EINVAL;
407 	}
408 
409 	return 0;
410 }
411 
ast2500_sdrammc_get_info(struct udevice * dev,struct ram_info * info)412 static int ast2500_sdrammc_get_info(struct udevice *dev, struct ram_info *info)
413 {
414 	struct dram_info *priv = dev_get_priv(dev);
415 
416 	*info = priv->info;
417 
418 	return 0;
419 }
420 
421 static struct ram_ops ast2500_sdrammc_ops = {
422 	.get_info = ast2500_sdrammc_get_info,
423 };
424 
425 static const struct udevice_id ast2500_sdrammc_ids[] = {
426 	{ .compatible = "aspeed,ast2500-sdrammc" },
427 	{ }
428 };
429 
430 U_BOOT_DRIVER(sdrammc_ast2500) = {
431 	.name = "aspeed_ast2500_sdrammc",
432 	.id = UCLASS_RAM,
433 	.of_match = ast2500_sdrammc_ids,
434 	.ops = &ast2500_sdrammc_ops,
435 	.ofdata_to_platdata = ast2500_sdrammc_ofdata_to_platdata,
436 	.probe = ast2500_sdrammc_probe,
437 	.priv_auto_alloc_size = sizeof(struct dram_info),
438 };
439