d

 

mtd_info

mtd_info는 메모리 장치의 특성을 나타내는 구조체

59 struct mtd_info {
60 u_char type;
61         u_int32_t flags;
62         u_int32_t size;  // Total size of the MTD
63
64         /* "Major" erase size for the device. Naive users may take this
65          * to be the only erase size available, or may use the more detailed
66          * information below if they desire
67          */
68         u_int32_t erasesize;
85
86         // Kernel-only stuff starts here.
87         char *name;
88         int index;
89
90         // oobinfo is a nand_oobinfo structure, which can be set by iotcl (MEMSETOOBINFO)
91         struct nand_oobinfo oobinfo;
92         u_int32_t oobavail;  // Number of bytes in OOB area available for fs
93
94         /* Data for variable erase regions. If numeraseregions is zero,
95          * it means that the whole device has erasesize as given above.
96          */
97         int numeraseregions;
98         struct mtd_erase_region_info *eraseregions;
99
100         /* This really shouldn't be here. It can go away in 2.5 */
101         u_int32_t bank_size;
102
103         int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
104
105         /* This stuff for eXecute-In-Place */
106         int (*point) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char **mtdbuf);
107
108         /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
109         void (*unpoint) (struct mtd_info *mtd, u_char * addr, loff_t from, size_t len);
110
111
112         int (*read) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
113         int (*write) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
114
115         int (*read_ecc) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf, u_char *eccbuf, struct nand_oobinfo *oobsel);
116         int (*write_ecc) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf, u_char *eccbuf, struct nand_oobinfo *oobsel);
117
118         int (*read_oob) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
119         int (*write_oob) (struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf);
120
121         /*
122          * Methods to access the protection register area, present in some
123          * flash devices. The user data is one time programmable but the
124          * factory data is read only.
125          */
126         int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
127         int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
128         int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf, size_t len);
129         int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
130         int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf);
131         int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from, size_t len);
132
133         /* kvec-based read/write methods. We need these especially for NAND flash,
134            with its limited number of write cycles per erase.
135            NB: The 'count' parameter is the number of _vectors_, each of
136            which contains an (ofs, len) tuple.
137         */
138         int (*readv) (struct mtd_info *mtd, struct kvec *vecs, unsigned long count, loff_t from, size_t *retlen);
139         int (*readv_ecc) (struct mtd_info *mtd, struct kvec *vecs, unsigned long count, loff_t from,
140                 size_t *retlen, u_char *eccbuf, struct nand_oobinfo *oobsel);
141         int (*writev) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to, size_t *retlen);
142         int (*writev_ecc) (struct mtd_info *mtd, const struct kvec *vecs, unsigned long count, loff_t to,
143                 size_t *retlen, u_char *eccbuf, struct nand_oobinfo *oobsel);
144
145         /* Sync */
146         void (*sync) (struct mtd_info *mtd);
147
148         /* Chip-supported device locking */
149         int (*lock) (struct mtd_info *mtd, loff_t ofs, size_t len);
150         int (*unlock) (struct mtd_info *mtd, loff_t ofs, size_t len);
151
152         /* Power Management functions */
153         int (*suspend) (struct mtd_info *mtd);
154         void (*resume) (struct mtd_info *mtd);
155
156         /* Bad block management functions */
157         int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
158         int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
159
160         struct notifier_block reboot_notifier;  /* default mode before reboot */
161
162         void *priv;
163
164         struct module *owner;
165         int usecount;
166 };

플랫폼 디바이스 드라이버

플랫폼 드라이버 s3c2440_nand_driver 는 다음과 같이 정의된다.
Linux 2.6에서 나오는 Platform Device Driver model이다.
KObject을 기반으로, 객체 기반의 계층적 디바이스 드라이버 모델이다. (마치 Windows WDM처럼)
등록된 버스 디바이스가 있고, 버스에 새로운 디바이스가 붙으면 버스 드라이버가 디바이스를 탐지해서 해당 디바이스에 맞는 디바이스 드라이버를 구동하는 식이다.

아래는 플랫폼 디바이스 정의다.
16 struct platform_device {
17         const char      * name;
18         u32             id;
19         struct device   dev;
20         u32 num_resources;
21         struct resource * resource;
22 };

아래는 플랫폼 드라이버 정의다.
47 struct platform_driver {
48         int (*probe)(struct platform_device *);
49         int (*remove)(struct platform_device *);
50         void (*shutdown)(struct platform_device *);
51         int (*suspend)(struct platform_device *, pm_message_t state);
52         int (*resume)(struct platform_device *);
53         struct device_driver driver;
54 };

예로 s3c2440의 nand platform driver는 다음처럼 정의되고,
705 static struct platform_driver s3c2440_nand_driver = {
706         .probe          = s3c2440_nand_probe,
707         .remove         = s3c2410_nand_remove,
708         .driver         = {
709                 .name   = "s3c2440-nand",
710                 .owner  = THIS_MODULE,
711         },
712 };

device는 아래처럼 정의된다.
120 /* NAND Controller */
121
122 static struct resource s3c_nand_resource[] = {
123         [0] = {
124                 .start = S3C2410_PA_NAND,
125                 .end   = S3C2410_PA_NAND + S3C24XX_SZ_NAND - 1,
126                 .flags = IORESOURCE_MEM,
127         }
128 };

130 struct platform_device s3c_device_nand = {
131         .name             = "s3c2410-nand",
132         .id               = -1,
133         .num_resources    = ARRAY_SIZE(s3c_nand_resource),
134         .resource         = s3c_nand_resource,
135 };

일단 smdk2440 board machine init할때 nand 플랫폼 디바이스는 등록된다.

112 static struct platform_device __initdata *smdk_devs[] = {
113         &s3c_device_nand,
114 };

102 static struct s3c2410_platform_nand smdk_nand_info = {
103         .tacls          = 20,
104         .twrph0         = 60,
105         .twrph1         = 20,
106         .nr_sets        = ARRAY_SIZE(smdk_nand_sets),
107         .sets           = smdk_nand_sets,
108 };

116 void __init smdk_machine_init(void)
117 {
118         /* Configure the LEDs (even if we have no LED support)*/
119
120         s3c2410_gpio_cfgpin(S3C2410_GPF4, S3C2410_GPF4_OUTP);
121         s3c2410_gpio_cfgpin(S3C2410_GPF5, S3C2410_GPF5_OUTP);
122         s3c2410_gpio_cfgpin(S3C2410_GPF6, S3C2410_GPF6_OUTP);
123         s3c2410_gpio_cfgpin(S3C2410_GPF7, S3C2410_GPF7_OUTP);
124
125         s3c2410_gpio_setpin(S3C2410_GPF4, 1);
126         s3c2410_gpio_setpin(S3C2410_GPF5, 1);
127         s3c2410_gpio_setpin(S3C2410_GPF6, 1);
128         s3c2410_gpio_setpin(S3C2410_GPF7, 1);
129
130         s3c_device_nand.dev.platform_data = &smdk_nand_info;
131
132         platform_add_devices(smdk_devs, ARRAY_SIZE(smdk_devs)); <--- 여기
133
134         s3c2410_pm_init();
135 }



mtd_blktrans_ops

35 struct mtd_blktrans_ops {
36         char *name;
37         int major;
38         int part_bits;
39
40         /* Access functions */
41         int (*readsect)(struct mtd_blktrans_dev *dev,
42                     unsigned long block, char *buffer);
43         int (*writesect)(struct mtd_blktrans_dev *dev,
44 unsigned long block, char *buffer);
45
46         /* Block layer ioctls */
47         int (*getgeo)(struct mtd_blktrans_dev *dev, struct hd_geometry *geo);
48         int (*flush)(struct mtd_blktrans_dev *dev);
49
50         /* Called with mtd_table_mutex held; no race with add/remove */
51         int (*open)(struct mtd_blktrans_dev *dev);
52         int (*release)(struct mtd_blktrans_dev *dev);
53
54         /* Called on {de,}registration and on subsequent addition/removal
55            of devices, with mtd_table_mutex held. */
56         void (*add_mtd)(struct mtd_blktrans_ops *tr, struct mtd_info *mtd);
57         void (*remove_dev)(struct mtd_blktrans_dev *dev);
58
59         struct list_head devs;
60         struct list_head list;
61         struct module *owner;
62
63         struct mtd_blkcore_priv *blkcore_priv;
64 };