嵌入式开发者社区
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
6 O& o. L. u) R3 @. G: `
核心板2:DDR2 256M Byte NAND FLASH 8G bit
0 S4 k" J8 }2 j' }
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?
8 x k0 a* `/ P
5 v9 F! I9 N1 w! s8 Y
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?
8 L: D; J4 Z+ \# o( p
& a8 ^; j0 m& v& W3 h8 m
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:
4 Q' O& N* h% E0 I, h6 o# z5 R
/*
* `) M3 |. l: x% y# U+ t$ `
* Check memory range for valid RAM. A simple memory test determines
' Y& q0 `% b2 G" v5 c
* the actually available RAM size between addresses `base' and
& |: U& b7 i- T$ T6 m6 }2 A
* `base + maxsize'.
! S+ o* x9 |. z6 S! R |
*/
! I" [8 x' @/ v% B) M
long get_ram_size(long *base, long maxsize)
! N( @& f6 |% r; d0 H' u5 B
{
5 F% [& r# _0 k" x& r
volatile long *addr;
& x$ f+ ]; }' _! G$ |5 S* l
long save[32];
( k4 W( E7 N, |2 u
long cnt;
$ T3 }( M' M- d1 I: B+ u7 F- f) Y& e
long val;
. |4 @8 l7 H' r$ `$ P! R/ S* r5 |
long size;
+ C. R+ s% A9 f* P" j7 `
int i = 0;
) q1 y* T r; _! C- j& v" d
8 `0 {/ K" [3 I
for (cnt = (maxsize / sizeof (long)) >> 1; cnt > 0; cnt >>= 1) {
: `! j6 a3 i! |# Y! t8 d
addr = base + cnt; /* pointer arith! */
8 d8 ?! t) F% t U) @. D' ]0 P- Z9 C: |
sync ();
9 B+ E& B6 |3 C
save[i++] = *addr;
; o, ~8 L' m$ R1 H$ n: t! D- p
sync ();
/ J) E/ ` K9 I# d3 H
*addr = ~cnt;
: J) o0 }( K2 Y- ]% d0 {' I8 k
}
2 \7 w0 ]& U3 [' G; F
4 X" z. ?+ N, d- \1 m
addr = base;
# z# k6 W0 s5 N1 c0 s6 K+ {- F
sync ();
8 L5 c: Y* G7 s7 E8 R
save
= *addr;
' z# m6 J1 @5 y
sync ();
1 X& P+ g9 G% ?' ?4 l( P% U
*addr = 0;
) J! ^6 q" m( i# n" U
' Y; K8 w% o$ g% E1 f
sync ();
# @2 V" y7 z3 \ c
if ((val = *addr) != 0) {
6 L8 f. r) _8 N+ ]( M# o; q r
/* Restore the original data before leaving the function.
! q3 X( A7 H; m9 O8 B7 C
*/
) q; |7 p5 H, k3 [4 {' Z
sync ();
+ G2 r A- Z4 i
*addr = save
;
" S7 g6 V: c5 V0 M! {7 P, Y1 X. A/ F
for (cnt = 1; cnt < maxsize / sizeof(long); cnt <<= 1) {
( a% L& Y$ y$ j! I
addr = base + cnt;
/ N" u: t) [9 F5 G
sync ();
, `0 n: }* s1 ^" a
*addr = save[--i];
( H8 n/ U7 a* B. Q. o
}
, l% ~3 t A# d. @
return (0);
) U8 L8 k# i, C
}
0 g- x+ b6 g! E' {- J
0 ~, D4 R; P7 `: A
for (cnt = 1; cnt < maxsize / sizeof (long); cnt <<= 1) {
% v3 k6 {" f" V' l4 L% b
addr = base + cnt; /* pointer arith! */
6 |3 P. j" _( ^4 U& [ |* I, P* C
val = *addr;
% P) G9 x, @' ?0 X4 k7 D
*addr = save[--i];
& g: k# H# U5 [2 x! B1 K. Z8 E
if (val != ~cnt) {
. `( p5 |4 [+ x8 Y P: m2 @
size = cnt * sizeof (long);
& F) [' F+ x$ y3 y9 ]2 c. T/ D
/* Restore the original data before leaving the function.
$ n+ F+ u0 r0 p
*/
+ M x/ M+ T/ W
for (cnt <<= 1; cnt < maxsize / sizeof (long); cnt <<= 1) {
1 C# J7 V2 `+ L' K# i/ n' E& ?
addr = base + cnt;
' S# @6 _- }+ h6 l( w
*addr = save[--i];
3 p% h1 ~. s1 l5 T
}
# J" o4 ^% d7 F3 {3 V
return (size);
0 b1 _2 L3 A8 d
}
. m& M# J: W* T7 c9 ^
}
# k3 j9 ?" y' I$ _- _6 F+ l
* K/ \1 P! E- F- T+ q8 Y, O% h
return (maxsize);
6 Q* E& C0 h D) W; q; r
}
- l& J5 v; r" h' G" R
int dram_init(void)
: E- ^% a1 Z; P, l$ `* t! _
{
7 Y- U7 ]9 c# ]9 A4 \, A
/* dram_init must store complete ramsize in gd->ram_size */
9 Z' |# d( W% `6 a9 W$ p8 r
gd->ram_size = get_ram_size(
# w' R! _1 A, |2 Y2 w
(void *)CONFIG_SYS_SDRAM_BASE,
8 a7 D+ }3 Z) Y; ^' ?" P2 T
CONFIG_MAX_RAM_BANK_SIZE);
+ }( i7 g. ^% X( Q; s
return 0;
/ T& ?6 a. P6 W0 o% f
}
e8 L+ N/ c1 q% W
- B* r$ x0 c4 _4 q+ h7 z/ J
+ G3 |: Q7 A* t4 [. Q
0 w/ f/ K V4 Z0 N" G% I ]2 g/ b
- ]- N# i$ {. N6 H6 a
FLASH是通过检查FLASH内部的ID识别容量,希望对您有帮助!
0 x; g8 s* D8 B* I
7 r: n% @/ ~/ f5 Q- i
w# T' [7 r6 o
3 {& v" Y: W* n2 P7 Z: z
欢迎光临 嵌入式开发者社区 (https://www.51ele.net/)
Powered by Discuz! X3.4