xref: /openbmc/linux/drivers/mtd/spi-nor/xilinx.c (revision f05643a0)
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 XILINX_RDSR_OP(buf)						\
19 	SPI_MEM_OP(SPI_MEM_OP_CMD(XILINX_OP_RDSR, 0),			\
20 		   SPI_MEM_OP_NO_ADDR,					\
21 		   SPI_MEM_OP_NO_DUMMY,					\
22 		   SPI_MEM_OP_DATA_IN(1, buf, 0))
23 
24 #define S3AN_INFO(_jedec_id, _n_sectors, _page_size)			\
25 		.id = {							\
26 			((_jedec_id) >> 16) & 0xff,			\
27 			((_jedec_id) >> 8) & 0xff,			\
28 			(_jedec_id) & 0xff				\
29 			},						\
30 		.id_len = 3,						\
31 		.sector_size = (8 * (_page_size)),			\
32 		.n_sectors = (_n_sectors),				\
33 		.page_size = (_page_size),				\
34 		.addr_width = 3,					\
35 		.flags = SPI_NOR_NO_FR
36 
37 /* Xilinx S3AN share MFR with Atmel SPI NOR */
38 static const struct flash_info xilinx_nor_parts[] = {
39 	/* Xilinx S3AN Internal Flash */
40 	{ "3S50AN", S3AN_INFO(0x1f2200, 64, 264) },
41 	{ "3S200AN", S3AN_INFO(0x1f2400, 256, 264) },
42 	{ "3S400AN", S3AN_INFO(0x1f2400, 256, 264) },
43 	{ "3S700AN", S3AN_INFO(0x1f2500, 512, 264) },
44 	{ "3S1400AN", S3AN_INFO(0x1f2600, 512, 528) },
45 };
46 
47 /*
48  * This code converts an address to the Default Address Mode, that has non
49  * power of two page sizes. We must support this mode because it is the default
50  * mode supported by Xilinx tools, it can access the whole flash area and
51  * changing over to the Power-of-two mode is irreversible and corrupts the
52  * original data.
53  * Addr can safely be unsigned int, the biggest S3AN device is smaller than
54  * 4 MiB.
55  */
56 static u32 s3an_nor_convert_addr(struct spi_nor *nor, u32 addr)
57 {
58 	u32 page_size = nor->params->page_size;
59 	u32 offset, page;
60 
61 	offset = addr % page_size;
62 	page = addr / page_size;
63 	page <<= (page_size > 512) ? 10 : 9;
64 
65 	return page | offset;
66 }
67 
68 /**
69  * xilinx_nor_read_sr() - Read the Status Register on S3AN flashes.
70  * @nor:	pointer to 'struct spi_nor'.
71  * @sr:		pointer to a DMA-able buffer where the value of the
72  *              Status Register will be written.
73  *
74  * Return: 0 on success, -errno otherwise.
75  */
76 static int xilinx_nor_read_sr(struct spi_nor *nor, u8 *sr)
77 {
78 	int ret;
79 
80 	if (nor->spimem) {
81 		struct spi_mem_op op = XILINX_RDSR_OP(sr);
82 
83 		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
84 
85 		ret = spi_mem_exec_op(nor->spimem, &op);
86 	} else {
87 		ret = spi_nor_controller_ops_read_reg(nor, XILINX_OP_RDSR, sr,
88 						      1);
89 	}
90 
91 	if (ret)
92 		dev_dbg(nor->dev, "error %d reading SR\n", ret);
93 
94 	return ret;
95 }
96 
97 /**
98  * xilinx_nor_sr_ready() - Query the Status Register of the S3AN flash to see
99  * if the flash is ready for new commands.
100  * @nor:	pointer to 'struct spi_nor'.
101  *
102  * Return: 1 if ready, 0 if not ready, -errno on errors.
103  */
104 static int xilinx_nor_sr_ready(struct spi_nor *nor)
105 {
106 	int ret;
107 
108 	ret = xilinx_nor_read_sr(nor, nor->bouncebuf);
109 	if (ret)
110 		return ret;
111 
112 	return !!(nor->bouncebuf[0] & XSR_RDY);
113 }
114 
115 static int xilinx_nor_setup(struct spi_nor *nor,
116 			    const struct spi_nor_hwcaps *hwcaps)
117 {
118 	u32 page_size;
119 	int ret;
120 
121 	ret = xilinx_nor_read_sr(nor, nor->bouncebuf);
122 	if (ret)
123 		return ret;
124 
125 	nor->erase_opcode = XILINX_OP_SE;
126 	nor->program_opcode = XILINX_OP_PP;
127 	nor->read_opcode = SPINOR_OP_READ;
128 	nor->flags |= SNOR_F_NO_OP_CHIP_ERASE;
129 
130 	/*
131 	 * This flashes have a page size of 264 or 528 bytes (known as
132 	 * Default addressing mode). It can be changed to a more standard
133 	 * Power of two mode where the page size is 256/512. This comes
134 	 * with a price: there is 3% less of space, the data is corrupted
135 	 * and the page size cannot be changed back to default addressing
136 	 * mode.
137 	 *
138 	 * The current addressing mode can be read from the XRDSR register
139 	 * and should not be changed, because is a destructive operation.
140 	 */
141 	if (nor->bouncebuf[0] & XSR_PAGESIZE) {
142 		/* Flash in Power of 2 mode */
143 		page_size = (nor->params->page_size == 264) ? 256 : 512;
144 		nor->params->page_size = page_size;
145 		nor->mtd.writebufsize = page_size;
146 		nor->params->size = 8 * page_size * nor->info->n_sectors;
147 		nor->mtd.erasesize = 8 * page_size;
148 	} else {
149 		/* Flash in Default addressing mode */
150 		nor->params->convert_addr = s3an_nor_convert_addr;
151 		nor->mtd.erasesize = nor->info->sector_size;
152 	}
153 
154 	return 0;
155 }
156 
157 static void xilinx_nor_late_init(struct spi_nor *nor)
158 {
159 	nor->params->setup = xilinx_nor_setup;
160 	nor->params->ready = xilinx_nor_sr_ready;
161 }
162 
163 static const struct spi_nor_fixups xilinx_nor_fixups = {
164 	.late_init = xilinx_nor_late_init,
165 };
166 
167 const struct spi_nor_manufacturer spi_nor_xilinx = {
168 	.name = "xilinx",
169 	.parts = xilinx_nor_parts,
170 	.nparts = ARRAY_SIZE(xilinx_nor_parts),
171 	.fixups = &xilinx_nor_fixups,
172 };
173