xref: /openbmc/linux/drivers/mtd/spi-nor/xilinx.c (revision fbb6b31a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2005, Intec Automation Inc.
4  * Copyright (C) 2014, Freescale Semiconductor, Inc.
5  */
6 
7 #include <linux/mtd/spi-nor.h>
8 
9 #include "core.h"
10 
11 #define XILINX_OP_SE		0x50	/* Sector erase */
12 #define XILINX_OP_PP		0x82	/* Page program */
13 #define XILINX_OP_RDSR		0xd7	/* Read status register */
14 
15 #define XSR_PAGESIZE		BIT(0)	/* Page size in Po2 or Linear */
16 #define XSR_RDY			BIT(7)	/* Ready */
17 
18 #define S3AN_INFO(_jedec_id, _n_sectors, _page_size)			\
19 		.id = {							\
20 			((_jedec_id) >> 16) & 0xff,			\
21 			((_jedec_id) >> 8) & 0xff,			\
22 			(_jedec_id) & 0xff				\
23 			},						\
24 		.id_len = 3,						\
25 		.sector_size = (8 * (_page_size)),			\
26 		.n_sectors = (_n_sectors),				\
27 		.page_size = (_page_size),				\
28 		.addr_width = 3,					\
29 		.flags = SPI_NOR_NO_FR
30 
31 /* Xilinx S3AN share MFR with Atmel SPI NOR */
32 static const struct flash_info xilinx_nor_parts[] = {
33 	/* Xilinx S3AN Internal Flash */
34 	{ "3S50AN", S3AN_INFO(0x1f2200, 64, 264) },
35 	{ "3S200AN", S3AN_INFO(0x1f2400, 256, 264) },
36 	{ "3S400AN", S3AN_INFO(0x1f2400, 256, 264) },
37 	{ "3S700AN", S3AN_INFO(0x1f2500, 512, 264) },
38 	{ "3S1400AN", S3AN_INFO(0x1f2600, 512, 528) },
39 };
40 
41 /*
42  * This code converts an address to the Default Address Mode, that has non
43  * power of two page sizes. We must support this mode because it is the default
44  * mode supported by Xilinx tools, it can access the whole flash area and
45  * changing over to the Power-of-two mode is irreversible and corrupts the
46  * original data.
47  * Addr can safely be unsigned int, the biggest S3AN device is smaller than
48  * 4 MiB.
49  */
50 static u32 s3an_nor_convert_addr(struct spi_nor *nor, u32 addr)
51 {
52 	u32 page_size = nor->params->page_size;
53 	u32 offset, page;
54 
55 	offset = addr % page_size;
56 	page = addr / page_size;
57 	page <<= (page_size > 512) ? 10 : 9;
58 
59 	return page | offset;
60 }
61 
62 /**
63  * xilinx_nor_read_sr() - Read the Status Register on S3AN flashes.
64  * @nor:	pointer to 'struct spi_nor'.
65  * @sr:		pointer to a DMA-able buffer where the value of the
66  *              Status Register will be written.
67  *
68  * Return: 0 on success, -errno otherwise.
69  */
70 static int xilinx_nor_read_sr(struct spi_nor *nor, u8 *sr)
71 {
72 	int ret;
73 
74 	if (nor->spimem) {
75 		struct spi_mem_op op =
76 			SPI_MEM_OP(SPI_MEM_OP_CMD(XILINX_OP_RDSR, 0),
77 				   SPI_MEM_OP_NO_ADDR,
78 				   SPI_MEM_OP_NO_DUMMY,
79 				   SPI_MEM_OP_DATA_IN(1, sr, 0));
80 
81 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
82 
83 		ret = spi_mem_exec_op(nor->spimem, &op);
84 	} else {
85 		ret = spi_nor_controller_ops_read_reg(nor, XILINX_OP_RDSR, sr,
86 						      1);
87 	}
88 
89 	if (ret)
90 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
91 
92 	return ret;
93 }
94 
95 /**
96  * xilinx_nor_sr_ready() - Query the Status Register of the S3AN flash to see
97  * if the flash is ready for new commands.
98  * @nor:	pointer to 'struct spi_nor'.
99  *
100  * Return: 1 if ready, 0 if not ready, -errno on errors.
101  */
102 static int xilinx_nor_sr_ready(struct spi_nor *nor)
103 {
104 	int ret;
105 
106 	ret = xilinx_nor_read_sr(nor, nor->bouncebuf);
107 	if (ret)
108 		return ret;
109 
110 	return !!(nor->bouncebuf[0] & XSR_RDY);
111 }
112 
113 static int xilinx_nor_setup(struct spi_nor *nor,
114 			    const struct spi_nor_hwcaps *hwcaps)
115 {
116 	u32 page_size;
117 	int ret;
118 
119 	ret = xilinx_nor_read_sr(nor, nor->bouncebuf);
120 	if (ret)
121 		return ret;
122 
123 	nor->erase_opcode = XILINX_OP_SE;
124 	nor->program_opcode = XILINX_OP_PP;
125 	nor->read_opcode = SPINOR_OP_READ;
126 	nor->flags |= SNOR_F_NO_OP_CHIP_ERASE;
127 
128 	/*
129 	 * This flashes have a page size of 264 or 528 bytes (known as
130 	 * Default addressing mode). It can be changed to a more standard
131 	 * Power of two mode where the page size is 256/512. This comes
132 	 * with a price: there is 3% less of space, the data is corrupted
133 	 * and the page size cannot be changed back to default addressing
134 	 * mode.
135 	 *
136 	 * The current addressing mode can be read from the XRDSR register
137 	 * and should not be changed, because is a destructive operation.
138 	 */
139 	if (nor->bouncebuf[0] & XSR_PAGESIZE) {
140 		/* Flash in Power of 2 mode */
141 		page_size = (nor->params->page_size == 264) ? 256 : 512;
142 		nor->params->page_size = page_size;
143 		nor->mtd.writebufsize = page_size;
144 		nor->params->size = 8 * page_size * nor->info->n_sectors;
145 		nor->mtd.erasesize = 8 * page_size;
146 	} else {
147 		/* Flash in Default addressing mode */
148 		nor->params->convert_addr = s3an_nor_convert_addr;
149 		nor->mtd.erasesize = nor->info->sector_size;
150 	}
151 
152 	return 0;
153 }
154 
155 static void xilinx_nor_late_init(struct spi_nor *nor)
156 {
157 	nor->params->setup = xilinx_nor_setup;
158 	nor->params->ready = xilinx_nor_sr_ready;
159 }
160 
161 static const struct spi_nor_fixups xilinx_nor_fixups = {
162 	.late_init = xilinx_nor_late_init,
163 };
164 
165 const struct spi_nor_manufacturer spi_nor_xilinx = {
166 	.name = "xilinx",
167 	.parts = xilinx_nor_parts,
168 	.nparts = ARRAY_SIZE(xilinx_nor_parts),
169 	.fixups = &xilinx_nor_fixups,
170 };
171