xref: /OK3568_Linux_fs/kernel/drivers/mtd/nand/raw/sm_common.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright © 2009 - Maxim Levitsky
4*4882a593Smuzhiyun  * Common routines & support for SmartMedia/xD format
5*4882a593Smuzhiyun  */
6*4882a593Smuzhiyun #include <linux/bitops.h>
7*4882a593Smuzhiyun #include <linux/mtd/mtd.h>
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun /* Full oob structure as written on the flash */
10*4882a593Smuzhiyun struct sm_oob {
11*4882a593Smuzhiyun 	uint32_t reserved;
12*4882a593Smuzhiyun 	uint8_t data_status;
13*4882a593Smuzhiyun 	uint8_t block_status;
14*4882a593Smuzhiyun 	uint8_t lba_copy1[2];
15*4882a593Smuzhiyun 	uint8_t ecc2[3];
16*4882a593Smuzhiyun 	uint8_t lba_copy2[2];
17*4882a593Smuzhiyun 	uint8_t ecc1[3];
18*4882a593Smuzhiyun } __packed;
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun /* one sector is always 512 bytes, but it can consist of two nand pages */
22*4882a593Smuzhiyun #define SM_SECTOR_SIZE		512
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun /* oob area is also 16 bytes, but might be from two pages */
25*4882a593Smuzhiyun #define SM_OOB_SIZE		16
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun /* This is maximum zone size, and all devices that have more that one zone
28*4882a593Smuzhiyun    have this size */
29*4882a593Smuzhiyun #define SM_MAX_ZONE_SIZE 	1024
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun /* support for small page nand */
32*4882a593Smuzhiyun #define SM_SMALL_PAGE 		256
33*4882a593Smuzhiyun #define SM_SMALL_OOB_SIZE	8
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun int sm_register_device(struct mtd_info *mtd, int smartmedia);
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun 
sm_sector_valid(struct sm_oob * oob)39*4882a593Smuzhiyun static inline int sm_sector_valid(struct sm_oob *oob)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun 	return hweight16(oob->data_status) >= 5;
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun 
sm_block_valid(struct sm_oob * oob)44*4882a593Smuzhiyun static inline int sm_block_valid(struct sm_oob *oob)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun 	return hweight16(oob->block_status) >= 7;
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun 
sm_block_erased(struct sm_oob * oob)49*4882a593Smuzhiyun static inline int sm_block_erased(struct sm_oob *oob)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun 	static const uint32_t erased_pattern[4] = {
52*4882a593Smuzhiyun 		0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	/* First test for erased block */
55*4882a593Smuzhiyun 	if (!memcmp(oob, erased_pattern, sizeof(*oob)))
56*4882a593Smuzhiyun 		return 1;
57*4882a593Smuzhiyun 	return 0;
58*4882a593Smuzhiyun }
59