S3C2440之NAND FLASH移植到S3C2410的驱动分析[一]
S3C2440A的NAND FLASH驱动移植到S3C2410还是有些不一样的，最主要的这两个IC的NAND FLASH的寄存器有些不一样，请看下面的两者之间不同：
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft end-user
// license agreement (EULA) under which you licensed this SOFTWARE PRODUCT.
// If you did not accept the terms of the EULA, you are not authorized to use
// this source code. For a copy of the EULA, please see the LICENSE.RTF on your
// install media.
//
//------------------------------------------------------------------------------
//
// Header: s3c2410x_nand.h
//
// Defines the NAND controller CPU register layout and definitions.
//
#ifndef __S3C2410X_NAND_H
#define __S3C2410X_NAND_H
#if __cplusplus
extern "C"
{
#endif
//------------------------------------------------------------------------------
// Type: S3C2410X_NAND_REG
//
// NAND Flash controller register layout. This register bank is located
// by the constant CPU_BASE_REG_XX_NAND in the configuration file
// cpu_base_reg_cfg.h.
//
typedef struct
{
UINT32 NFCONF; // configuration reg
UINT8 NFCMD; // command set reg
UINT8 pad1[3]; // pad
UINT8 NFADDR; // address set reg
UINT8 pad2[3]; // pad
UINT8 NFDATA; // data reg
UINT8 pad3[3]; // pad
UINT32 NFSTAT; // operation status reg
UINT32 NFECC; // error correction code 0
} S3C2410X_NAND_REG, *PS3C2410X_NAND_REG;
#if __cplusplus
}
#endif
#endif
上面的代码是S3C2410A的寄存器，我们在看看S3C2440A的寄存器地址说明：
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft end-user
// license agreement (EULA) under which you licensed this SOFTWARE PRODUCT.
// If you did not accept the terms of the EULA, you are not authorized to use
// this source code. For a copy of the EULA, please see the LICENSE.RTF on your
// install media.
//
//------------------------------------------------------------------------------
//
// Header: s3c2440a_nand.h
//
// Defines the NAND controller CPU register layout and definitions.
//
#ifndef __S3C2440A_NAND_H
#define __S3C2440A_NAND_H
#if __cplusplus
extern "C"
{
#endif
//------------------------------------------------------------------------------
// Type: S3C2440A_NAND_REG
//
// NAND Flash controller register layout. This register bank is located
// by the constant CPU_BASE_REG_XX_NAND in the configuration file
// cpu_base_reg_cfg.h.
//
typedef struct
{
UINT32 NFCONF; // configuration reg
UINT32 NFCONT;
UINT8 NFCMD; // command set reg
UINT8 d0[3];
UINT8 NFADDR; // address set reg
UINT8 d1[3];
UINT8 NFDATA; // data reg
UINT8 d2[3];
UINT32 NFMECCD0;
UINT32 NFMECCD1;
UINT32 NFSECCD;
UINT32 NFSTAT; // operation status reg
UINT32 NFESTAT0;
UINT32 NFESTAT1;
UINT32 NFMECC0; // error correction code 0
UINT32 NFMECC1; // error correction code 1
UINT32 NFSECC;
UINT32 NFSBLK;
UINT32 NFEBLK; // error correction code 2
} S3C2440A_NAND_REG, *PS3C2440A_NAND_REG;
#if __cplusplus
}
#endif
#endif
这两者之间的差别是很大的。因此移植起来的难点主要是ECC部分，同时还有个别寄存器位地址不一样，需要修改，见下面：
// Use Macros here to avoid extra over head for c function calls #define READ_REGISTER_BYTE(p) (*(PBYTE)(p)) #define WRITE_REGISTER_BYTE(p, v) (*(PBYTE)(p)) = (v) #define READ_REGISTER_USHORT(p) (*(PUSHORT)(p)) #define WRITE_REGISTER_USHORT(p, v) (*(PUSHORT)(p)) = (v) #define READ_REGISTER_ULONG(p) (*(PULONG)(p)) #define WRITE_REGISTER_ULONG(p, v) (*(PULONG)(p)) = (v)
以上的代码不论S3C2410还是S3C2440都可以用，我在移植的时候，这两部是一样的。当然至于S3C2443和S3C2450这部分的寄存器改变并不多，不过S3C2450的BSP中NAND FLASH驱动还是有很大的变化，那以后再来分析吧，现在还是分析这个，WINCE5.0下的。WINCE6.0的我还没有来得急移植呢。我一般喜欢动手自己移植一遍，这样能深入的了解WINCE的流程，同时对这颗IC，也更熟悉。看看两者之间的不同吧。
S3C2440A的寄存器宏定义：
// MACROS
#define NF_CE_L() WRITE_REGISTER_USHORT(pNFCONT, (USHORT) (READ_REGISTER_USHORT(pNFCONT) & ~(1<<1)))
#define NF_CE_H() WRITE_REGISTER_USHORT(pNFCONT, (USHORT) (READ_REGISTER_USHORT(pNFCONT) | (1<<1)))
#define NF_CMD(cmd) WRITE_REGISTER_USHORT(pNFCMD, (USHORT) (cmd))
#define NF_ADDR(addr) WRITE_REGISTER_USHORT(pNFADDR, (USHORT) (addr))
#define NF_DATA_R() READ_REGISTER_BYTE(pNFDATA)
#define NF_DATA_W(val) WRITE_REGISTER_BYTE(pNFDATA, (BYTE) (val))
#define NF_DATA_R4() READ_REGISTER_ULONG(pNFDATA)
#define NF_DATA_W4(val) WRITE_REGISTER_ULONG(pNFDATA, (ULONG) (val))
#define NF_STAT() READ_REGISTER_USHORT(pNFSTAT)
#define NF_MECC_UnLock() WRITE_REGISTER_USHORT(pNFCONT, (USHORT) (READ_REGISTER_USHORT(pNFCONT) & ~(1<<5)))
#define NF_MECC_Lock() WRITE_REGISTER_USHORT(pNFCONT, (USHORT) (READ_REGISTER_USHORT(pNFCONT) | (1<<5)))
#define NF_RSTECC() WRITE_REGISTER_USHORT(pNFCONT, (USHORT) (READ_REGISTER_USHORT(pNFCONT) | (1<<4)))
#define NF_WAITRB() {while(!(NF_STAT() & (1<<1))) ;}
#define NF_CLEAR_RB() WRITE_REGISTER_USHORT(pNFSTAT, (USHORT) (READ_REGISTER_USHORT(pNFSTAT) | (1<<2)))
#define NF_DETECT_RB() {while(!(NF_STAT() & (1<<2)));}
#define NF_ECC() READ_REGISTER_ULONG(pNFECC)
S3C2410A的寄存器宏定义：
// MACROS
#define NF_CE_L() WRITE_REGISTER_USHORT(pNFCONF, (USHORT) (READ_REGISTER_USHORT(pNFCONF) & ~(1 << 11)))
#define NF_CE_H() WRITE_REGISTER_USHORT(pNFCONF, (USHORT) (READ_REGISTER_USHORT(pNFCONF) | (1 << 11)))
#define NF_CMD(cmd) WRITE_REGISTER_USHORT(pNFCMD, (USHORT) (cmd))
#define NF_ADDR(addr) WRITE_REGISTER_USHORT(pNFADDR, (USHORT) (addr))
#define NF_DATA_R() READ_REGISTER_USHORT(pNFDATA)
#define NF_DATA_W(val) WRITE_REGISTER_BYTE(pNFDATA, (BYTE)(val))
#define NF_STAT() READ_REGISTER_USHORT(pNFSTAT)
#define NF_RSTECC() WRITE_REGISTER_USHORT(pNFCONF, (USHORT) (READ_REGISTER_USHORT(pNFCONF) | (1 << 12)))
#define NF_WAITRB() {while(!(NF_STAT() & (1<<0))) ;}
#define NF_DETECT_RB() {while(!(NF_STAT() & 0x01));}
#define NF_ECC() READ_REGISTER_ULONG(pNFECC)
S3C2410的寄存器是我修改过的寄存器定义，主要不同之处：NF_CE_L()、NF_CE_H()、NF_RSTECC()、NF_WAITRB()、NF_DETECT_RB()，这些寄存器可以通过两者的Datasheet上的详细说明可以分别出来。这里不详细解说啦！寄存器的修改是移植NAND FLASH驱动的第一步。也是最重要的一步，下一步主要分析驱动移植需要注意的部分。
未完待续。。。。。。