xref: /openbmc/u-boot/arch/arm/mach-mvebu/dram.c (revision ae07d609)
1 /*
2  * (C) Copyright 2009
3  * Marvell Semiconductor <www.marvell.com>
4  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <config.h>
10 #include <common.h>
11 #include <asm/io.h>
12 #include <asm/arch/cpu.h>
13 #include <asm/arch/soc.h>
14 
15 #if defined(CONFIG_ARCH_MVEBU)
16 /* Use common XOR definitions for A3x and AXP */
17 #include "../../../drivers/ddr/marvell/axp/xor.h"
18 #include "../../../drivers/ddr/marvell/axp/xor_regs.h"
19 #endif
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 struct sdram_bank {
24 	u32	win_bar;
25 	u32	win_sz;
26 };
27 
28 struct sdram_addr_dec {
29 	struct sdram_bank sdram_bank[4];
30 };
31 
32 #define REG_CPUCS_WIN_ENABLE		(1 << 0)
33 #define REG_CPUCS_WIN_WR_PROTECT	(1 << 1)
34 #define REG_CPUCS_WIN_WIN0_CS(x)	(((x) & 0x3) << 2)
35 #define REG_CPUCS_WIN_SIZE(x)		(((x) & 0xff) << 24)
36 
37 #define SDRAM_SIZE_MAX			0xc0000000
38 
39 #define SCRUB_MAGIC		0xbeefdead
40 
41 #define SCRB_XOR_UNIT		0
42 #define SCRB_XOR_CHAN		1
43 #define SCRB_XOR_WIN		0
44 
45 #define XEBARX_BASE_OFFS	16
46 
47 /*
48  * mvebu_sdram_bar - reads SDRAM Base Address Register
49  */
50 u32 mvebu_sdram_bar(enum memory_bank bank)
51 {
52 	struct sdram_addr_dec *base =
53 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
54 	u32 result = 0;
55 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
56 
57 	if ((!enable) || (bank > BANK3))
58 		return 0;
59 
60 	result = readl(&base->sdram_bank[bank].win_bar);
61 	return result;
62 }
63 
64 /*
65  * mvebu_sdram_bs_set - writes SDRAM Bank size
66  */
67 static void mvebu_sdram_bs_set(enum memory_bank bank, u32 size)
68 {
69 	struct sdram_addr_dec *base =
70 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
71 	/* Read current register value */
72 	u32 reg = readl(&base->sdram_bank[bank].win_sz);
73 
74 	/* Clear window size */
75 	reg &= ~REG_CPUCS_WIN_SIZE(0xFF);
76 
77 	/* Set new window size */
78 	reg |= REG_CPUCS_WIN_SIZE((size - 1) >> 24);
79 
80 	writel(reg, &base->sdram_bank[bank].win_sz);
81 }
82 
83 /*
84  * mvebu_sdram_bs - reads SDRAM Bank size
85  */
86 u32 mvebu_sdram_bs(enum memory_bank bank)
87 {
88 	struct sdram_addr_dec *base =
89 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
90 	u32 result = 0;
91 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
92 
93 	if ((!enable) || (bank > BANK3))
94 		return 0;
95 	result = 0xff000000 & readl(&base->sdram_bank[bank].win_sz);
96 	result += 0x01000000;
97 	return result;
98 }
99 
100 void mvebu_sdram_size_adjust(enum memory_bank bank)
101 {
102 	u32 size;
103 
104 	/* probe currently equipped RAM size */
105 	size = get_ram_size((void *)mvebu_sdram_bar(bank),
106 			    mvebu_sdram_bs(bank));
107 
108 	/* adjust SDRAM window size accordingly */
109 	mvebu_sdram_bs_set(bank, size);
110 }
111 
112 #if defined(CONFIG_ARCH_MVEBU)
113 static u32 xor_ctrl_save;
114 static u32 xor_base_save;
115 static u32 xor_mask_save;
116 
117 static void mv_xor_init2(u32 cs)
118 {
119 	u32 reg, base, size, base2;
120 	u32 bank_attr[4] = { 0xe00, 0xd00, 0xb00, 0x700 };
121 
122 	xor_ctrl_save = reg_read(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT,
123 						     SCRB_XOR_CHAN));
124 	xor_base_save = reg_read(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT,
125 						   SCRB_XOR_WIN));
126 	xor_mask_save = reg_read(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT,
127 						   SCRB_XOR_WIN));
128 
129 	/* Enable Window x for each CS */
130 	reg = 0x1;
131 	reg |= (0x3 << 16);
132 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN), reg);
133 
134 	base = 0;
135 	size = mvebu_sdram_bs(cs) - 1;
136 	if (size) {
137 		base2 = ((base / (64 << 10)) << XEBARX_BASE_OFFS) |
138 			bank_attr[cs];
139 		reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
140 			  base2);
141 
142 		base += size + 1;
143 		size = (size / (64 << 10)) << 16;
144 		/* Window x - size - 256 MB */
145 		reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN), size);
146 	}
147 
148 	mv_xor_hal_init(0);
149 
150 	return;
151 }
152 
153 static void mv_xor_finish2(void)
154 {
155 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN),
156 		  xor_ctrl_save);
157 	reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
158 		  xor_base_save);
159 	reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
160 		  xor_mask_save);
161 }
162 
163 static void dram_ecc_scrubbing(void)
164 {
165 	int cs;
166 	u32 size, temp;
167 	u32 total_mem = 0;
168 	u64 total;
169 	u32 start_addr;
170 
171 	/*
172 	 * The DDR training code from the bin_hdr / SPL already
173 	 * scrubbed the DDR till 0x1000000. And the main U-Boot
174 	 * is loaded to an address < 0x1000000. So we need to
175 	 * skip this range to not re-scrub this area again.
176 	 */
177 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
178 	temp |= (1 << REG_SDRAM_CONFIG_IERR_OFFS);
179 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
180 
181 	for (cs = 0; cs < CONFIG_NR_DRAM_BANKS; cs++) {
182 		size = mvebu_sdram_bs(cs);
183 		if (size == 0)
184 			continue;
185 
186 		total = (u64)size;
187 		total_mem += (u32)(total / (1 << 30));
188 		start_addr = 0;
189 		mv_xor_init2(cs);
190 
191 		/* Skip first 16 MiB */
192 		if (0 == cs) {
193 			start_addr = 0x1000000;
194 			size -= start_addr;
195 		}
196 
197 		mv_xor_mem_init(SCRB_XOR_CHAN, start_addr, size - 1,
198 				SCRUB_MAGIC, SCRUB_MAGIC);
199 
200 		/* Wait for previous transfer completion */
201 		while (mv_xor_state_get(SCRB_XOR_CHAN) != MV_IDLE)
202 			;
203 
204 		mv_xor_finish2();
205 	}
206 
207 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
208 	temp &= ~(1 << REG_SDRAM_CONFIG_IERR_OFFS);
209 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
210 }
211 
212 static int ecc_enabled(void)
213 {
214 	if (reg_read(REG_SDRAM_CONFIG_ADDR) & (1 << REG_SDRAM_CONFIG_ECC_OFFS))
215 		return 1;
216 
217 	return 0;
218 }
219 
220 /* Return the width of the DRAM bus, or 0 for unknown. */
221 static int bus_width(void)
222 {
223 	int full_width = 0;
224 
225 	if (reg_read(REG_SDRAM_CONFIG_ADDR) & (1 << REG_SDRAM_CONFIG_WIDTH_OFFS))
226 		full_width = 1;
227 
228 	switch (mvebu_soc_family()) {
229 	case MVEBU_SOC_AXP:
230 	    return full_width ? 64 : 32;
231 	    break;
232 	case MVEBU_SOC_A375:
233 	case MVEBU_SOC_A38X:
234 	case MVEBU_SOC_MSYS:
235 	    return full_width ? 32 : 16;
236 	default:
237 	    return 0;
238 	}
239 }
240 
241 static int cycle_mode(void)
242 {
243 	int val = reg_read(REG_DUNIT_CTRL_LOW_ADDR);
244 
245 	return (val >> REG_DUNIT_CTRL_LOW_2T_OFFS) & REG_DUNIT_CTRL_LOW_2T_MASK;
246 }
247 
248 #else
249 static void dram_ecc_scrubbing(void)
250 {
251 }
252 
253 static int ecc_enabled(void)
254 {
255 	return 0;
256 }
257 #endif
258 
259 int dram_init(void)
260 {
261 	u64 size = 0;
262 	int i;
263 
264 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
265 		/*
266 		 * It is assumed that all memory banks are consecutive
267 		 * and without gaps.
268 		 * If the gap is found, ram_size will be reported for
269 		 * consecutive memory only
270 		 */
271 		if (mvebu_sdram_bar(i) != size)
272 			break;
273 
274 		/*
275 		 * Don't report more than 3GiB of SDRAM, otherwise there is no
276 		 * address space left for the internal registers etc.
277 		 */
278 		size += mvebu_sdram_bs(i);
279 		if (size > SDRAM_SIZE_MAX)
280 			size = SDRAM_SIZE_MAX;
281 	}
282 
283 	for (; i < CONFIG_NR_DRAM_BANKS; i++) {
284 		/* If above loop terminated prematurely, we need to set
285 		 * remaining banks' start address & size as 0. Otherwise other
286 		 * u-boot functions and Linux kernel gets wrong values which
287 		 * could result in crash */
288 		gd->bd->bi_dram[i].start = 0;
289 		gd->bd->bi_dram[i].size = 0;
290 	}
291 
292 
293 	if (ecc_enabled())
294 		dram_ecc_scrubbing();
295 
296 	gd->ram_size = size;
297 
298 	return 0;
299 }
300 
301 /*
302  * If this function is not defined here,
303  * board.c alters dram bank zero configuration defined above.
304  */
305 int dram_init_banksize(void)
306 {
307 	u64 size = 0;
308 	int i;
309 
310 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
311 		gd->bd->bi_dram[i].start = mvebu_sdram_bar(i);
312 		gd->bd->bi_dram[i].size = mvebu_sdram_bs(i);
313 
314 		/* Clip the banksize to 1GiB if it exceeds the max size */
315 		size += gd->bd->bi_dram[i].size;
316 		if (size > SDRAM_SIZE_MAX)
317 			mvebu_sdram_bs_set(i, 0x40000000);
318 	}
319 
320 	return 0;
321 }
322 
323 #if defined(CONFIG_ARCH_MVEBU)
324 void board_add_ram_info(int use_default)
325 {
326 	struct sar_freq_modes sar_freq;
327 	int mode;
328 	int width;
329 
330 	get_sar_freq(&sar_freq);
331 	printf(" (%d MHz, ", sar_freq.d_clk);
332 
333 	width = bus_width();
334 	if (width)
335 		printf("%d-bit, ", width);
336 
337 	mode = cycle_mode();
338 	/* Mode 0 = Single cycle
339 	 * Mode 1 = Two cycles   (2T)
340 	 * Mode 2 = Three cycles (3T)
341 	 */
342 	if (mode == 1)
343 		printf("2T, ");
344 	if (mode == 2)
345 		printf("3T, ");
346 
347 	if (ecc_enabled())
348 		printf("ECC");
349 	else
350 		printf("ECC not");
351 	printf(" enabled)");
352 }
353 #endif
354