xref: /openbmc/u-boot/arch/arm/mach-mvebu/dram.c (revision 62e92077)
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 #ifdef CONFIG_SYS_MVEBU_DDR_A38X
16 #include "../../../drivers/ddr/marvell/axp/xor.h"
17 #include "../../../drivers/ddr/marvell/axp/xor_regs.h"
18 #endif
19 #ifdef CONFIG_SYS_MVEBU_DDR_AXP
20 #include "../../../drivers/ddr/marvell/axp/xor.h"
21 #include "../../../drivers/ddr/marvell/axp/xor_regs.h"
22 #endif
23 
24 DECLARE_GLOBAL_DATA_PTR;
25 
26 struct sdram_bank {
27 	u32	win_bar;
28 	u32	win_sz;
29 };
30 
31 struct sdram_addr_dec {
32 	struct sdram_bank sdram_bank[4];
33 };
34 
35 #define REG_CPUCS_WIN_ENABLE		(1 << 0)
36 #define REG_CPUCS_WIN_WR_PROTECT	(1 << 1)
37 #define REG_CPUCS_WIN_WIN0_CS(x)	(((x) & 0x3) << 2)
38 #define REG_CPUCS_WIN_SIZE(x)		(((x) & 0xff) << 24)
39 
40 #define SDRAM_SIZE_MAX			0xc0000000
41 
42 #define SCRUB_MAGIC		0xbeefdead
43 
44 #define SCRB_XOR_UNIT		0
45 #define SCRB_XOR_CHAN		1
46 #define SCRB_XOR_WIN		0
47 
48 #define XEBARX_BASE_OFFS	16
49 
50 /*
51  * mvebu_sdram_bar - reads SDRAM Base Address Register
52  */
53 u32 mvebu_sdram_bar(enum memory_bank bank)
54 {
55 	struct sdram_addr_dec *base =
56 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
57 	u32 result = 0;
58 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
59 
60 	if ((!enable) || (bank > BANK3))
61 		return 0;
62 
63 	result = readl(&base->sdram_bank[bank].win_bar);
64 	return result;
65 }
66 
67 /*
68  * mvebu_sdram_bs_set - writes SDRAM Bank size
69  */
70 static void mvebu_sdram_bs_set(enum memory_bank bank, u32 size)
71 {
72 	struct sdram_addr_dec *base =
73 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
74 	/* Read current register value */
75 	u32 reg = readl(&base->sdram_bank[bank].win_sz);
76 
77 	/* Clear window size */
78 	reg &= ~REG_CPUCS_WIN_SIZE(0xFF);
79 
80 	/* Set new window size */
81 	reg |= REG_CPUCS_WIN_SIZE((size - 1) >> 24);
82 
83 	writel(reg, &base->sdram_bank[bank].win_sz);
84 }
85 
86 /*
87  * mvebu_sdram_bs - reads SDRAM Bank size
88  */
89 u32 mvebu_sdram_bs(enum memory_bank bank)
90 {
91 	struct sdram_addr_dec *base =
92 		(struct sdram_addr_dec *)MVEBU_SDRAM_BASE;
93 	u32 result = 0;
94 	u32 enable = 0x01 & readl(&base->sdram_bank[bank].win_sz);
95 
96 	if ((!enable) || (bank > BANK3))
97 		return 0;
98 	result = 0xff000000 & readl(&base->sdram_bank[bank].win_sz);
99 	result += 0x01000000;
100 	return result;
101 }
102 
103 void mvebu_sdram_size_adjust(enum memory_bank bank)
104 {
105 	u32 size;
106 
107 	/* probe currently equipped RAM size */
108 	size = get_ram_size((void *)mvebu_sdram_bar(bank),
109 			    mvebu_sdram_bs(bank));
110 
111 	/* adjust SDRAM window size accordingly */
112 	mvebu_sdram_bs_set(bank, size);
113 }
114 
115 #if defined(CONFIG_SYS_MVEBU_DDR_A38X) || defined(CONFIG_SYS_MVEBU_DDR_AXP)
116 static u32 xor_ctrl_save;
117 static u32 xor_base_save;
118 static u32 xor_mask_save;
119 
120 static void mv_xor_init2(u32 cs)
121 {
122 	u32 reg, base, size, base2;
123 	u32 bank_attr[4] = { 0xe00, 0xd00, 0xb00, 0x700 };
124 
125 	xor_ctrl_save = reg_read(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT,
126 						     SCRB_XOR_CHAN));
127 	xor_base_save = reg_read(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT,
128 						   SCRB_XOR_WIN));
129 	xor_mask_save = reg_read(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT,
130 						   SCRB_XOR_WIN));
131 
132 	/* Enable Window x for each CS */
133 	reg = 0x1;
134 	reg |= (0x3 << 16);
135 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN), reg);
136 
137 	base = 0;
138 	size = mvebu_sdram_bs(cs) - 1;
139 	if (size) {
140 		base2 = ((base / (64 << 10)) << XEBARX_BASE_OFFS) |
141 			bank_attr[cs];
142 		reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
143 			  base2);
144 
145 		base += size + 1;
146 		size = (size / (64 << 10)) << 16;
147 		/* Window x - size - 256 MB */
148 		reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN), size);
149 	}
150 
151 	mv_xor_hal_init(0);
152 
153 	return;
154 }
155 
156 static void mv_xor_finish2(void)
157 {
158 	reg_write(XOR_WINDOW_CTRL_REG(SCRB_XOR_UNIT, SCRB_XOR_CHAN),
159 		  xor_ctrl_save);
160 	reg_write(XOR_BASE_ADDR_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
161 		  xor_base_save);
162 	reg_write(XOR_SIZE_MASK_REG(SCRB_XOR_UNIT, SCRB_XOR_WIN),
163 		  xor_mask_save);
164 }
165 
166 static void dram_ecc_scrubbing(void)
167 {
168 	int cs;
169 	u32 size, temp;
170 	u32 total_mem = 0;
171 	u64 total;
172 	u32 start_addr;
173 
174 	/*
175 	 * The DDR training code from the bin_hdr / SPL already
176 	 * scrubbed the DDR till 0x1000000. And the main U-Boot
177 	 * is loaded to an address < 0x1000000. So we need to
178 	 * skip this range to not re-scrub this area again.
179 	 */
180 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
181 	temp |= (1 << REG_SDRAM_CONFIG_IERR_OFFS);
182 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
183 
184 	for (cs = 0; cs < CONFIG_NR_DRAM_BANKS; cs++) {
185 		size = mvebu_sdram_bs(cs) - 1;
186 		if (size == 0)
187 			continue;
188 
189 		total = (u64)size + 1;
190 		total_mem += (u32)(total / (1 << 30));
191 		start_addr = 0;
192 		mv_xor_init2(cs);
193 
194 		/* Skip first 16 MiB */
195 		if (0 == cs) {
196 			start_addr = 0x1000000;
197 			size -= start_addr;
198 		}
199 
200 		mv_xor_mem_init(SCRB_XOR_CHAN, start_addr, size,
201 				SCRUB_MAGIC, SCRUB_MAGIC);
202 
203 		/* Wait for previous transfer completion */
204 		while (mv_xor_state_get(SCRB_XOR_CHAN) != MV_IDLE)
205 			;
206 
207 		mv_xor_finish2();
208 	}
209 
210 	temp = reg_read(REG_SDRAM_CONFIG_ADDR);
211 	temp &= ~(1 << REG_SDRAM_CONFIG_IERR_OFFS);
212 	reg_write(REG_SDRAM_CONFIG_ADDR, temp);
213 }
214 
215 static int ecc_enabled(void)
216 {
217 	if (reg_read(REG_SDRAM_CONFIG_ADDR) & (1 << REG_SDRAM_CONFIG_ECC_OFFS))
218 		return 1;
219 
220 	return 0;
221 }
222 #else
223 static void dram_ecc_scrubbing(void)
224 {
225 }
226 
227 static int ecc_enabled(void)
228 {
229 	return 0;
230 }
231 #endif
232 
233 int dram_init(void)
234 {
235 	u64 size = 0;
236 	int i;
237 
238 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
239 		/*
240 		 * It is assumed that all memory banks are consecutive
241 		 * and without gaps.
242 		 * If the gap is found, ram_size will be reported for
243 		 * consecutive memory only
244 		 */
245 		if (mvebu_sdram_bar(i) != size)
246 			break;
247 
248 		/*
249 		 * Don't report more than 3GiB of SDRAM, otherwise there is no
250 		 * address space left for the internal registers etc.
251 		 */
252 		size += mvebu_sdram_bs(i);
253 		if (size > SDRAM_SIZE_MAX)
254 			size = SDRAM_SIZE_MAX;
255 	}
256 
257 	for (; i < CONFIG_NR_DRAM_BANKS; i++) {
258 		/* If above loop terminated prematurely, we need to set
259 		 * remaining banks' start address & size as 0. Otherwise other
260 		 * u-boot functions and Linux kernel gets wrong values which
261 		 * could result in crash */
262 		gd->bd->bi_dram[i].start = 0;
263 		gd->bd->bi_dram[i].size = 0;
264 	}
265 
266 
267 	if (ecc_enabled())
268 		dram_ecc_scrubbing();
269 
270 	gd->ram_size = size;
271 
272 	return 0;
273 }
274 
275 /*
276  * If this function is not defined here,
277  * board.c alters dram bank zero configuration defined above.
278  */
279 void dram_init_banksize(void)
280 {
281 	u64 size = 0;
282 	int i;
283 
284 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
285 		gd->bd->bi_dram[i].start = mvebu_sdram_bar(i);
286 		gd->bd->bi_dram[i].size = mvebu_sdram_bs(i);
287 
288 		/* Clip the banksize to 1GiB if it exceeds the max size */
289 		size += gd->bd->bi_dram[i].size;
290 		if (size > SDRAM_SIZE_MAX)
291 			mvebu_sdram_bs_set(i, 0x40000000);
292 	}
293 }
294 
295 void board_add_ram_info(int use_default)
296 {
297 	if (ecc_enabled())
298 		printf(" (ECC");
299 	else
300 		printf(" (ECC not");
301 	printf(" enabled)");
302 }
303