标题: TL138 uboot是怎么区分配置两款核心板的 [打印本页] 作者: Mr.Loser 时间: 2014-9-11 09:33 标题: TL138 uboot是怎么区分配置两款核心板的 核心板1：DDR2 128M Byte NAND FLASH 4G bit! r& m9 `$ U7 \1 D/ ^9 @7 {; U
核心板2：DDR2 256M Byte NAND FLASH 8G bit # ^! Y! V- H7 M这两个核心板公共一个uboot，DDR2的配置肯定是不同的，uboot怎么检查到是哪个核心板，然后去执行相应的配置呢？" M- D- w6 G* S1 G6 _! U$ m7 T
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是不是通过读NAND FLASH的ID，两款核心板NAND FLASH不同，ID也不同，这样读到了ID就知道是哪个核心板了？( X' P& t: l8 V( G5 k/ p/ c
7 e: l7 W+ t; n0 \ 作者: 2532609929 时间: 2014-9-11 18:55
DDR通过检查最大有效地址来识别容量，具体请看uboot的common/memsize.c文件中的检查代码，也可以看如下： ( z* B- i, B6 S/* 5 I& y' s4 A3 x. z0 {9 E/ {* Check memory range for valid RAM. A simple memory test determines , a$ u$ `7 k& `1 H" a% `* the actually available RAM size between addresses `base' and : T; _+ z' ]; |* `base + maxsize'.; T d. y5 u9 V
*/ @: n( N% g& D2 C0 }9 P6 G! D# n1 Ulong get_ram_size(long *base, long maxsize) 0 _* t/ j T4 B. U& V8 |{ 6 d) O6 k9 }) L& v volatile long *addr; C& }) D; E. u2 C! ^ long save[32]; 2 P+ n% J E+ t/ l long cnt; / g# W! s' y! s long val; 1 Z1 ]" E; }8 @! x: o5 m; Y" y long size; 9 D! Q7 N% ~2 \0 M int i = 0; / x1 C% _ p6 J6 T; i2 n, r+ r" K2 _! C" O% S2 @6 Q& v
for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) { 5 Z' W( l( w. ^ addr = base + cnt; /* pointer arith! */! S) N, Y _3 n
sync ();, w& }, T+ D- k* ?3 U8 `
save[i++] = *addr; 6 n; |* S: \8 H. o3 j/ ]9 d sync (); , t9 i* B; e: S1 h6 H4 T *addr = ~cnt; 9 g8 C9 V" E$ H: _( e }9 i+ f# p5 `- c* ]
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addr = base; ( `( m C. p7 O3 M4 \) Y sync ();" C4 Y- m9 u! [! F
save = *addr;8 K k$ |$ |4 ?% `& ^ K
sync (); 4 f0 z @ }" D8 _$ s! f *addr = 0;3 O1 g2 M# s& i8 G# a& x
5 H" z9 d0 D8 ?. e, N1 G sync (); * f4 W# B ]2 U2 n/ N if ((val = *addr) != 0) { + b, E% z6 Z2 a' u, J# T* [ /* Restore the original data before leaving the function. % }6 d+ Q! q& b5 E */ ) U& P8 K: T1 j | sync ();! k# e5 h1 S' W5 P" ^3 l1 v
*addr = save;2 u5 Z3 y. s, g$ K" E# l
for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) { # j$ @1 N: ], l0 f addr = base + cnt;8 e' m+ K d4 p! o! T- a6 B
sync (); # ]+ D- j% \5 m9 A5 Q! o& W! K *addr = save[--i];! D$ H/ Q' l: F/ S ]9 A. g7 {" @
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return (0);1 Y( Z+ S" [4 d: p3 s
} 7 c9 ^3 i: C# Y5 _2 ]' `& J- A 7 u1 x: P4 X! d8 { for (cnt = 1; cnt < maxsize / sizeof (long); cnt <<= 1) { / f0 p7 }. a8 z, g addr = base + cnt; /* pointer arith! */$ b$ M: b* Z5 m
val = *addr; - F$ u) ?9 S7 v *addr = save[--i]; ( M2 T5 z: R+ J' u' f1 Z T if (val != ~cnt) {/ K% U) h: _' Q1 V
size = cnt * sizeof (long); 7 v/ U8 K, E8 N7 O' P /* Restore the original data before leaving the function. 3 s% W* f4 u# T6 [0 A */ 9 H# x( V4 U `6 V% D3 P for (cnt <<= 1; cnt < maxsize / sizeof (long); cnt <<= 1) { 7 L$ w4 N* W ?1 P) m% {) b# b$ J addr = base + cnt; ) I4 A3 f7 g# W6 F ?9 T7 @ *addr = save[--i];& B5 f& a8 }* v* ^0 {
} 8 p) n/ b9 q5 s) ~4 b! p( d6 P1 D0 H return (size); ! R9 h% p. O: `% U& o% ? }2 q& s: }' s$ ^- \! @' h2 n
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8 q% g# D3 G: r return (maxsize); ; N6 f9 S2 ]4 Y% S}) F; g' P/ c; G0 M* e
int dram_init(void)) n# z& E2 M7 ] Q# N1 G" E
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/* dram_init must store complete ramsize in gd->ram_size */ / |* m9 l- G5 w; r7 F gd->ram_size = get_ram_size(. W+ ?6 |# l; i! C% a8 r
(void *)CONFIG_SYS_SDRAM_BASE,% @3 L( I- n) o- w' z# y/ L% S
CONFIG_MAX_RAM_BANK_SIZE); ' o1 c+ x, ]9 {1 d return 0; # O( h0 S% B. w1 T) \9 B} # L3 G+ t. E8 H% m V8 d/ c2 N( I9 ~; B: V5 j
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FLASH是通过检查FLASH内部的ID识别容量，希望对您有帮助！/ @% i. ]) r( @0 s; |- G
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