xref: /openbmc/u-boot/drivers/mtd/nand/raw/denali_spl.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2014       Panasonic Corporation
4  * Copyright (C) 2014-2015  Masahiro Yamada <yamada.masahiro@socionext.com>
5  */
6 
7 #include <common.h>
8 #include <asm/io.h>
9 #include <asm/unaligned.h>
10 #include <linux/mtd/rawnand.h>
11 #include "denali.h"
12 
13 #define DENALI_MAP01		(1 << 26)	/* read/write pages in PIO */
14 #define DENALI_MAP10		(2 << 26)	/* high-level control plane */
15 
16 #define INDEX_CTRL_REG		0x0
17 #define INDEX_DATA_REG		0x10
18 
19 #define SPARE_ACCESS		0x41
20 #define MAIN_ACCESS		0x42
21 #define PIPELINE_ACCESS		0x2000
22 
23 #define BANK(x) ((x) << 24)
24 
25 static void __iomem *denali_flash_mem =
26 			(void __iomem *)CONFIG_SYS_NAND_DATA_BASE;
27 static void __iomem *denali_flash_reg =
28 			(void __iomem *)CONFIG_SYS_NAND_REGS_BASE;
29 
30 static const int flash_bank;
31 static int page_size, oob_size, pages_per_block;
32 
33 static void index_addr(uint32_t address, uint32_t data)
34 {
35 	writel(address, denali_flash_mem + INDEX_CTRL_REG);
36 	writel(data, denali_flash_mem + INDEX_DATA_REG);
37 }
38 
39 static int wait_for_irq(uint32_t irq_mask)
40 {
41 	unsigned long timeout = 1000000;
42 	uint32_t intr_status;
43 
44 	do {
45 		intr_status = readl(denali_flash_reg + INTR_STATUS(flash_bank));
46 
47 		if (intr_status & INTR__ECC_UNCOR_ERR) {
48 			debug("Uncorrected ECC detected\n");
49 			return -EBADMSG;
50 		}
51 
52 		if (intr_status & irq_mask)
53 			break;
54 
55 		udelay(1);
56 		timeout--;
57 	} while (timeout);
58 
59 	if (!timeout) {
60 		debug("Timeout with interrupt status %08x\n", intr_status);
61 		return -EIO;
62 	}
63 
64 	return 0;
65 }
66 
67 static void read_data_from_flash_mem(uint8_t *buf, int len)
68 {
69 	int i;
70 	uint32_t *buf32;
71 
72 	/* transfer the data from the flash */
73 	buf32 = (uint32_t *)buf;
74 
75 	/*
76 	 * Let's take care of unaligned access although it rarely happens.
77 	 * Avoid put_unaligned() for the normal use cases since it leads to
78 	 * a bit performance regression.
79 	 */
80 	if ((unsigned long)buf32 % 4) {
81 		for (i = 0; i < len / 4; i++)
82 			put_unaligned(readl(denali_flash_mem + INDEX_DATA_REG),
83 				      buf32++);
84 	} else {
85 		for (i = 0; i < len / 4; i++)
86 			*buf32++ = readl(denali_flash_mem + INDEX_DATA_REG);
87 	}
88 
89 	if (len % 4) {
90 		u32 tmp;
91 
92 		tmp = cpu_to_le32(readl(denali_flash_mem + INDEX_DATA_REG));
93 		buf = (uint8_t *)buf32;
94 		for (i = 0; i < len % 4; i++) {
95 			*buf++ = tmp;
96 			tmp >>= 8;
97 		}
98 	}
99 }
100 
101 int denali_send_pipeline_cmd(int page, int ecc_en, int access_type)
102 {
103 	uint32_t addr, cmd;
104 	static uint32_t page_count = 1;
105 
106 	writel(ecc_en, denali_flash_reg + ECC_ENABLE);
107 
108 	/* clear all bits of intr_status. */
109 	writel(0xffff, denali_flash_reg + INTR_STATUS(flash_bank));
110 
111 	addr = BANK(flash_bank) | page;
112 
113 	/* setup the acccess type */
114 	cmd = DENALI_MAP10 | addr;
115 	index_addr(cmd, access_type);
116 
117 	/* setup the pipeline command */
118 	index_addr(cmd, PIPELINE_ACCESS | page_count);
119 
120 	cmd = DENALI_MAP01 | addr;
121 	writel(cmd, denali_flash_mem + INDEX_CTRL_REG);
122 
123 	return wait_for_irq(INTR__LOAD_COMP);
124 }
125 
126 static int nand_read_oob(void *buf, int page)
127 {
128 	int ret;
129 
130 	ret = denali_send_pipeline_cmd(page, 0, SPARE_ACCESS);
131 	if (ret < 0)
132 		return ret;
133 
134 	read_data_from_flash_mem(buf, oob_size);
135 
136 	return 0;
137 }
138 
139 static int nand_read_page(void *buf, int page)
140 {
141 	int ret;
142 
143 	ret = denali_send_pipeline_cmd(page, 1, MAIN_ACCESS);
144 	if (ret < 0)
145 		return ret;
146 
147 	read_data_from_flash_mem(buf, page_size);
148 
149 	return 0;
150 }
151 
152 static int nand_block_isbad(void *buf, int block)
153 {
154 	int ret;
155 
156 	ret = nand_read_oob(buf, block * pages_per_block);
157 	if (ret < 0)
158 		return ret;
159 
160 	return *((uint8_t *)buf + CONFIG_SYS_NAND_BAD_BLOCK_POS) != 0xff;
161 }
162 
163 /* nand_init() - initialize data to make nand usable by SPL */
164 void nand_init(void)
165 {
166 	/* access to main area */
167 	writel(0, denali_flash_reg + TRANSFER_SPARE_REG);
168 
169 	/*
170 	 * These registers are expected to be already set by the hardware
171 	 * or earlier boot code.  So we read these values out.
172 	 */
173 	page_size = readl(denali_flash_reg + DEVICE_MAIN_AREA_SIZE);
174 	oob_size = readl(denali_flash_reg + DEVICE_SPARE_AREA_SIZE);
175 	pages_per_block = readl(denali_flash_reg + PAGES_PER_BLOCK);
176 }
177 
178 int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
179 {
180 	int block, page, column, readlen;
181 	int ret;
182 	int force_bad_block_check = 1;
183 
184 	page = offs / page_size;
185 	column = offs % page_size;
186 
187 	block = page / pages_per_block;
188 	page = page % pages_per_block;
189 
190 	while (size) {
191 		if (force_bad_block_check || page == 0) {
192 			ret = nand_block_isbad(dst, block);
193 			if (ret < 0)
194 				return ret;
195 
196 			if (ret) {
197 				block++;
198 				continue;
199 			}
200 		}
201 
202 		force_bad_block_check = 0;
203 
204 		ret = nand_read_page(dst, block * pages_per_block + page);
205 		if (ret < 0)
206 			return ret;
207 
208 		readlen = min(page_size - column, (int)size);
209 
210 		if (unlikely(column)) {
211 			/* Partial page read */
212 			memmove(dst, dst + column, readlen);
213 			column = 0;
214 		}
215 
216 		size -= readlen;
217 		dst += readlen;
218 		page++;
219 		if (page == pages_per_block) {
220 			block++;
221 			page = 0;
222 		}
223 	}
224 
225 	return 0;
226 }
227 
228 void nand_deselect(void) {}
229