iTop4412 3.0.15内核移植到linux4.4.34(一)

打算借linux移植学习内核启动过程，及4412各外设驱动原理

移植时，先修改一些config，然后解决编译出现的问题

System Type-->Multiple platform selection

[*]ARMv7 based platforms(Cortex-A,PJ4,Scorpion, Krait)

System Type--->Samsung EXYNOS

[*]SAMSUNG EXYNOS4

[*]SAMSUNG EXYNOS4412

File systems--->Network File Systems--->

<>NFS client support for NFS version 2

<*>NFS client support for NFS version 3

[]NFS server support for NFS version 3

[]NFS server support for NFS version 4

编译出现错误：

scripts/sign-file.c:23:30: fatal error: openssl/opensslv.h: No such file or directory

解决：apt-get install libssl-dev

/tmp/ccKduzSd.s: Assembler messages:

/tmp/ccKduzSd.s:869: Error: garbage following instruction -- `dmb ishst'

/tmp/ccKduzSd.s:888: Error: garbage following instruction -- `dmb ishst'

/tmp/ccKduzSd.s:919: Error: garbage following instruction -- `dmb ish'

/tmp/ccKduzSd.s:931: Error: garbage following instruction -- `dsb ishst'

解决：

System Type->ARM system type (ARM Ltd. Vesatile family)

配置改为

 [*] MMU-based Paged Memory Management Support

 ARM system type (Allow multiple platforms to be selected) 

 [*] Samsung EXYNOS  ---> SAMSUNG EXYNOS4

     SAMSUNG EXYNOS4412

问题：

  CC      arch/arm/kernel/suspend.o

/tmp/ccgcmPjb.s: Assembler messages:

/tmp/ccgcmPjb.s:243: Error: garbage following instruction -- `dsb nshst'

/tmp/ccgcmPjb.s:251: Error: garbage following instruction -- `dsb nsh'

解决：

Power management options  --->

[] Suspend to RAM and standby 

问题：

  CC      arch/arm/mm/fault.o

/tmp/ccEM41mf.s: Assembler messages:

/tmp/ccEM41mf.s:632: Error: garbage following instruction -- `dsb ishst'

make[1]: *** [arch/arm/mm/fault.o] Error 1

解决：

替换函数

static inline void flush_pmd_entry(pmd_t *pmd)

{
const unsigned int __tlb_flag = __cpu_tlb_flags;

if (tlb_flag(TLB_DCLEAN))
asm("mcr
p15, 0, %0, c7, c10, 1 @ flush_pmd"
: : "r" (pmd) : "cc");

if (tlb_flag(TLB_L2CLEAN_FR))
asm("mcr
p15, 1, %0, c15, c9, 1  @ L2 flush_pmd"
: : "r" (pmd) : "cc");

if (tlb_flag(TLB_WB))
dsb();

}

出错：

CC      arch/arm/mm/flush.o

/tmp/ccobT12L.s: Assembler messages:

/tmp/ccobT12L.s:99: Error: garbage following instruction -- `dsb nshst'

/tmp/ccobT12L.s:107: Error: garbage following instruction -- `dsb nsh'

/tmp/ccobT12L.s:223: Error: garbage following instruction -- `dsb ishst'

/tmp/ccobT12L.s:308: Error: garbage following instruction -- `dsb nshst'

/tmp/ccobT12L.s:314: Error: garbage following instruction -- `dsb nsh'

/tmp/ccobT12L.s:386: Error: garbage following instruction -- `dsb nshst'

/tmp/ccobT12L.s:392: Error: garbage following instruction -- `dsb nsh'

/tmp/ccobT12L.s:427: Error: garbage following instruction -- `dsb ishst'

/tmp/ccobT12L.s:461: Error: garbage following instruction -- `dsb ishst'

/tmp/ccobT12L.s:516: Error: garbage following instruction -- `dsb ishst'

/tmp/ccobT12L.s:569: Error: garbage following instruction -- `dsb ishst'

make[1]: *** [arch/arm/mm/flush.o] Error 1

解决：

barrier.h

#if __LINUX_ARM_ARCH__ >= 7

#ifdef CONFIG_ARCH_EXYNOS
#define isb(option) __asm__ __volatile__ ("isb" : : : "memory")
#define dsb(option) __asm__ __volatile__ ("dsb" : : : "memory")
#define dmb(option) __asm__ __volatile__ ("dmb" : : : "memory")
#else
#define isb(option) __asm__ __volatile__ ("isb " #option : : : "memory")aa
#define dsb(option) __asm__ __volatile__ ("dsb " #option : : : "memory")
#define dmb(option) __asm__ __volatile__ ("dmb " #option : : : "memory")
#endif

问题：

arch/arm/mm/tlb-v7.S: Assembler messages:

arch/arm/mm/tlb-v7.S:38: Error: garbage following instruction -- `dsb ish'

arch/arm/mm/tlb-v7.S:59: Error: garbage following instruction -- `dsb ish'

arch/arm/mm/tlb-v7.S:72: Error: garbage following instruction -- `dsb ish'

arch/arm/mm/tlb-v7.S:87: Error: garbage following instruction -- `dsb ish'

make[1]: *** [arch/arm/mm/tlb-v7.o] Error 1

proc-v7.S与cache-v7.S也有相同问题

解决：

在对应文件中找到dsb ishst

替换为dsb

编译出错：

arch/arm/lib/testchangebit.S: Assembler messages:

arch/arm/lib/testchangebit.S:15: Error: garbage following instruction -- `dmb ish'

arch/arm/lib/testchangebit.S:15: Error: garbage following instruction -- `dmb ish'

make[1]: *** [arch/arm/lib/testchangebit.o] Error 1

修改arch\arm\include\asm\assembler.h

去掉ish

查看代码发现有个angel模式，不明白什么是这个模式，搜了下发现这个模式即ARM's standard semihosting interface ，用于外部调试，

是一种旧办法，现在基本不使用了。（参考：http://stackoverflow.com/questions/38550715/linux-booting-angel-booting）

至此编译通过