TL138 uboot是怎么区分配置两款核心板的

Mr.Loser · 发表于 2014-9-11 09:33:39

核心板1：DDR2 128M Byte NAND FLASH 4G bit
核心板2：DDR2 256M Byte NAND FLASH 8G bit
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？

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？

2532609929 · 发表于 2014-9-11 18:55:41

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：
/*
* Check memory range for valid RAM. A simple memory test determines
* the actually available RAM size between addresses `base' and
* `base + maxsize'.
*/
long get_ram_size(long *base, long maxsize)
{
      volatile long *addr;
      long          save[32];
      long          cnt;
      long          val;
      long          size;
      int          i = 0;

      for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) {
            addr = base + cnt;       /* pointer arith! */
            sync ();
            save[i++] = *addr;
            sync ();
            *addr = ~cnt;
      }

      addr = base;
      sync ();
      save = *addr;
      sync ();
% \5 q- z/ s/ V* Z+ b/ t7 S       *addr = 0;
( t5 C6 j( `' ^  _; z
      sync ();% B" v9 {! f5 v) b8 _6 \7 e$ A
      if ((val = *addr) != 0) {' s. m% n  f* B! g3 x9 V3 q, X+ m
            /* Restore the original data before leaving the function.
+ x+ T4 r! O, A, U                */2 k; |+ W8 ^' M( ?' E
            sync ();% I$ P/ h) n. ]+ l7 m
            *addr = save;% I' e- m3 B3 W. p" t5 ~5 P5 I
            for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) {
5 o$ S7 R$ Z5 R! g6 y  m                      addr  = base + cnt;" h1 F5 x- a; s  x7 {. a
                     sync ();
' [0 M- S8 I6 I# Q$ g                      *addr = save[--i];
! C( Q# d' I0 ], ]9 ?: P- v             }$ o* E. V* z- b. B. K
            return (0);: ^( L: }# F7 |- b( X2 e8 N- }
      }6 Q/ y! U3 z6 z

9 g! \  J: o' g3 {* Q" p       for (cnt = 1; cnt < maxsize / sizeof (long); cnt <<= 1) {1 }" G: p5 w* r/ U  S- Q
            addr = base + cnt;       /* pointer arith! */
) p, O' E1 T( _# Y, y8 t             val = *addr;# x$ x+ @( H/ y% V4 a% u4 `
            *addr = save[--i];
4 Z/ D/ _: v5 i. O7 N& k5 j             if (val != ~cnt) {' p! V0 t- ?4 _- a& Q
                     size = cnt * sizeof (long);, W4 ~+ ]2 s8 p: D6 K9 {, x
                     /* Restore the original data before leaving the function.+ z& ^& L; n* k; T: P( k
                     */* K4 W! h! i$ o! p" A* N  j
                     for (cnt <<= 1; cnt < maxsize / sizeof (long); cnt <<= 1) {
+ r( _) k* R1 e* p: x4 E                               addr  = base + cnt;
& h2 T  L. N) f: Z* }                               *addr = save[--i];
: \. b- w( `. e! U' ]3 ?                      }; l3 p& ~$ d: i3 \
                     return (size);& P. w6 `% {' D% `4 w' o8 r( l
            }
) l! x! I% P# O4 E/ n. p4 t       }- n# O7 v) _0 Q8 ?' ]
" X" s4 g# h# o7 I9 B7 L
      return (maxsize);- O3 s& O9 c- w. ^' w; C4 p0 m( v& h5 m
}) r$ M) n2 b. v9 h% w: N
int dram_init(void); k4 Q$ C! |; J/ m. y) r# J
{  j! {# v& C) {* L( A4 B, I
      /* dram_init must store complete ramsize in gd->ram_size */: \$ m# X! V; D  F+ b! l' L" C6 E
      gd->ram_size = get_ram_size(
1 Y: w4 _$ _4 V7 w2 [                      (void *)CONFIG_SYS_SDRAM_BASE,- m+ a6 ]" D' n
                     CONFIG_MAX_RAM_BANK_SIZE);
9 P0 N. x; V7 |0 I9 a2 o, S       return 0;
+ l: h  W, l7 w( O}" T% x; q$ n. V

8 r. G; n$ r' A; ^8 B) ]2 v) u; j7 z0 V+ D4 q3 B

+ {0 R0 Q+ Z/ O7 u* V' _# i  m
0 Y; P# E6 O2 Z5 X% UFLASH是通过检查FLASH内部的ID识别容量，希望对您有帮助！, U7 E. l7 C/ Y
9 {7 K1 N; U. ^7 J2 L: o% l) h- s

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