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在 ARM 端 StarterWare 例程中 CMD 文件比 DSP 端多了这样一句
! ]0 t: G2 d* s/ F# |/* 重新配置程序入口点 */2 G3 U3 s; J- E
-e Entry- /****************************************************************************/4 B% H8 z% F0 a6 b1 B! p
- /* */5 Z. b" m; \7 @7 ~9 b2 U
- /* OMAPL138 及 DSP C6748 内存空间分配定义 */
( l: X) e9 P( a) r U4 r( E - /* */# Q. \( \' e4 w& s& ~
- /* 2015年04月20日 */
) ~: ^- e* I1 V3 T- i$ b( R - /* */
8 [) x" N( Y& N/ N: S - /****************************************************************************/. Y5 o+ N' H6 M! r7 g- B9 Z
- /* 堆栈 */' u! y9 o; d) b2 t( j: [. @/ g
- -stack 0x8000" H. f6 q: H$ `
- -heap 0x2000, z' S: v9 ?7 C: @) D6 `+ s. M
! p9 d) b9 j+ m- /* 重新配置程序入口点 */
$ H1 ^. a* N: N - -e Entry# p* ]9 x6 L# L
6 u! z& ~ \8 W- MEMORY- L, p" k7 n% N2 [9 b
- {( W( u% Y& Z j( k
- #ifdef DSP_CORE5 e; B" J- T. F: \
- /****************************************************************************/
$ j5 ~6 T- C, C9 R - /* */$ ^4 b3 J6 G* J: V' v' H
- /* DSP 专有内存区域 */
7 E0 `$ ]+ ?0 i4 W! G: p( O) Z# |: F" G) [ - /* */9 |) Y2 T' W; u& f; c& D. O- ^
- /****************************************************************************/4 P0 Z/ p% z, Q+ W- ]3 ]
- DSPL2ROM o = 0x00700000 l = 0x00100000 /* 1MB L2 DSP 本地 ROM (DSP ROM Bootloader) */& h9 U* B7 r6 r# E; A
- DSPL2RAM o = 0x00800000 l = 0x00040000 /* 256kB L2 DSP 本地 RAM */! d- s% G& `7 Q+ B. s8 S* _- ?
- DSPL1PRAM o = 0x00E00000 l = 0x00008000 /* 32kB L1 DSP 本地程序 RAM */* W4 x# ?5 I% P; Z6 g
- DSPL1DRAM o = 0x00F00000 l = 0x00008000 /* 32kB L1 DSP 本地数据 RAM */
5 B8 w* n5 Z5 P6 H1 p* Y - #endif
复制代码 这是一段汇编代码用于切换到特权模式
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OMAPL138_StarterWare_1_10_04_01\system_config\armv5\cgt\init.asm8 T: D# h. `0 |: G* k( H' H
- ;******************************************************************************4 n" K# b5 i f) D2 B
- ;
* k2 U, s8 e" c) G1 l& m) k8 u - ; init.asm - Init code routines9 \2 k- @) T+ L' E
- ;9 v' T$ E/ k; J# H
- ; Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/9 ?" }& L5 d7 [& r3 u
- ; All rights reserved.
q- i3 q7 x3 d4 s - ;
& c0 m+ H& K, S |+ w - ;******************************************************************************
: J, x/ K3 c: {$ d- X - ;****************************** Global Symbols*******************************
0 z; x+ s6 u; z& s" p4 w - .global Entry
. N$ _/ _# ~: Y2 J7 N5 W* U - .global start_boot4 \0 z! e. T$ m& n3 O1 {5 h
- .global __TI_auto_init
* [+ P8 w9 t& Q; p! ?3 _8 ]3 S
7 W# {$ M* z* ^- .ref __stack9 W/ N7 U. o6 K
- .ref __STACK_END
: T) e, ~( m, D- ]6 a& z. `9 m - .ref bss_start$ d3 c) U# @% z* A8 c
- .ref bss_end g; k d- I0 E- w+ Z
- .ref start_boot$ J8 s( L3 ~# P2 f" Z' v
- % [ g. o+ ~, t* N; D* I) o- v% `3 h6 U
- ;************************ Internal Definitions ******************************$ G- G2 N1 Q: Q' w" Q+ p) K
- ;1 z# F, m8 w3 u% `% [3 M4 Y; K) H
- ; Define the stack sizes for different modes. The user/system mode will use4 \; z: u3 P* b2 p
- ; the rest of the total stack size
m9 x( E3 k8 E& x) v5 [ - ;
0 a( f" C: C+ I1 W2 U9 c3 l
, ]2 \+ `& u! Y9 t% a- UND_STACK_SIZE .set 0x8
% D! B9 B$ b1 l - ABT_STACK_SIZE .set 0x8! g* }- v9 y- ~$ R: l
- FIQ_STACK_SIZE .set 0x8* W' f- C) ^2 p8 u# ^- T
- IRQ_STACK_SIZE .set 0x5001 k, \8 O& W- a) ^. a
- SVC_STACK_SIZE .set 0x85 f# X7 V+ G! ?4 k+ i# \
- ) F3 [) G! ]' I1 r. d
- ;1 X1 t2 v( V0 S' I
- ; to set the mode bits in CPSR for different modes
7 I7 y3 m2 H5 O( e( U, H8 e, y% O - ;
) e- h ?) _" P! M* `* v+ ^# {
/ h+ T* o$ N6 y2 ?! Q+ O! O- MODE_USR .set 0x10
1 {$ F C5 ~3 q5 l: P - MODE_FIQ .set 0x11
0 @! Y) B2 Z2 d8 N( c% {" u - MODE_IRQ .set 0x12. t1 C, w" c- `7 D& \# i+ m7 I
- MODE_SVC .set 0x13
$ ~) l! b" A0 r0 q, K6 w5 a - MODE_ABT .set 0x17
! U: o5 S4 @3 u& E- a! I0 M5 g - MODE_UND .set 0x1B
% N$ N8 {- t% M( J, X - MODE_SYS .set 0x1F
% l9 O* Y# ]# ?. Z- ^8 s/ T
, h6 S6 S2 {6 Y4 _) `6 d- I_F_BIT .set 0xC0# y) U+ {: B3 c6 P2 {
- - b0 j, @( O5 P, u$ h- L
- ;**************************** Code Seection ***********************************# X3 t2 b& t ~8 O: d1 \
- .text
. d7 S7 w R1 } - 0 G) l: F8 q! t. t
- ; I% j! s- n6 Q! S7 n
- ; This code is assembled for ARM instructions
5 k' M3 B0 ]$ O! Y( P - ;2 {' Z: M9 \$ n& E/ \/ {
- .state32/ _5 Q) y. D9 ?- U
& l- g3 M1 [; U6 \3 J+ G( k- ;******************************************************************************
. E% m! [+ L7 { K - ;
# j# h. k6 j; v' F+ n - ;******************************************************************************. ^! ~% Z6 e$ K8 e7 r/ N$ \0 R
- ;
" i8 C" e8 d) z - ; The reset handler sets up the stack pointers for all the modes. The FIQ and M# { a$ t* g$ m& }% E
- ; IRQ shall be disabled during this. Then, clearthe BSS sections, switch to the
% I" J, f' _# Z, m0 P - ; main() function.
7 `* V4 L. L1 {7 G7 n( ?1 \8 w - ;
% s" h, s9 ?) H8 d; p) M - Entry:
( y7 a/ @3 T+ ~& p1 a - ;; T- ]$ j* ~( a2 B. _4 m/ B+ q7 Y/ `
- ; Set up the Stack for Undefined mode
& e0 o5 g% W Y% ~ s - ;$ O& ?1 F9 i" E* X; Q7 b/ v
- LDR r0, _stackptr ; Read and align the stack pointer# y u. l& a( }) H2 f
- SUB r0, r0, #8
5 h5 J4 T3 h: k" V5 X( o, } - BIC r0, r0, #7 C9 G, A# e( N
- MSR cpsr_c, #MODE_UND|I_F_BIT ; switch to undef mode4 l [! N* ? x7 Q1 s
- MOV sp,r0 ; write the stack pointer
% w1 \# ~. g% g) p0 o. S - SUB r0, r0, #UND_STACK_SIZE ; give stack space
8 D& @; j: y& t h( M - ;" [0 P9 V9 G) \0 q0 j1 _: p1 |: O) p
- ; Set up the Stack for abort mode
6 X; v, ^2 B& f4 b - ;3 R* p! u: [* ?3 |0 F& w
- MSR cpsr_c, #MODE_ABT|I_F_BIT ; Change to abort mode2 \( m( O" K. g8 R7 B
- MOV sp, r0 ; write the stack pointer
2 @. w7 _1 S; i9 K+ S; t1 { - SUB r0,r0, #ABT_STACK_SIZE ; give stack space
. t9 y' {9 u' j* C - ;3 h% ~4 F1 w9 z6 g# m
- ; Set up the Stack for FIQ mode
* j$ B" h9 y1 l a0 V1 I - ;4 m) U1 y- \# |
- MSR cpsr_c, #MODE_FIQ|I_F_BIT ; change to FIQ mode
; q5 m9 K# p+ b/ o - MOV sp,r0 ; write the stack pointer6 A& ]5 H0 e$ j" W% N
- SUB r0,r0, #FIQ_STACK_SIZE ; give stack space
, y E* j6 _9 t" A: z1 f) A - ;
5 F, o" V" o, v& \! W1 y$ l+ s - ; Set up the Stack for IRQ mode
: [- [$ I6 a1 B' f- A - ;
# R1 e5 [* s d1 @1 x& R; X' U4 M% \ - MSR cpsr_c, #MODE_IRQ|I_F_BIT ; change to IRQ mode) ?2 N9 n' I. y. x
- MOV sp,r0 ; write the stack pointer u. i; ^; V5 Y+ r- h
- SUB r0,r0, #IRQ_STACK_SIZE ; give stack space
. c8 l& s g$ t0 e+ x i - ;4 c4 j6 Z; d& T6 c+ B% U* h
- ; Set up the Stack for SVC mode/ H \: W/ M: K1 c1 P9 R: @
- ;# z8 r# K5 o4 f x) p6 X, q& P6 s
- MSR cpsr_c, #MODE_SVC|I_F_BIT ; change to SVC mode2 g+ R6 E" H Z0 w# S6 k1 U3 @
- MOV sp,r0 ; write the stack pointer
, L2 s3 q; X8 R - SUB r0,r0, #SVC_STACK_SIZE ; give stack space3 D9 x' }3 {; }* L4 z: S
- ;
- u. A. u6 ^' c2 C( _! A' D - ; Set up the Stack for USer/System mode
: C# ?6 f/ O" \6 k7 i% ~ - ;+ _* Z7 V' v6 D1 [, Q. h6 |
- MSR cpsr_c, #MODE_SYS|I_F_BIT ; change to system mode9 t- }5 U% u' ^. W2 l/ \" l
- MOV sp,r0 ; write the stack pointer
% [& p3 I0 i7 R - & ~. r+ {" T4 R0 `
- ;
: F! B" V. Z# ^1 g0 z0 H - ; Clear the BSS section here
* Q$ p. K/ u2 p8 M3 T. g- r - ;2 a' g' x$ u* J7 E; s( ~
- Clear_Bss_Section:( D+ l$ K4 }4 C( s
- * o- S7 f" K7 P9 r. G( q; `
- LDR r0, _bss_start ; Start address of BSS
- W+ p& N% ^ [# L- u$ S4 _3 y - LDR r1, _bss_end ; End address of BSS
3 S; G' w8 R+ R) A# C- t - SUB r1,r1,#48 A8 g7 A! d h2 _; [5 c) o) ~
- MOV r2, #09 D, D% {" i( H; ?/ }# O
- Loop:
- W& k! U. V+ D& ^- Y3 | - STR r2, [r0], #4 ; Clear one word in BSS- I# F4 ]! E3 z# g! \8 [
- CMP r0, r17 {6 W, e( Q& m. m
- BLE Loop ; Clear till BSS end# ?, D! v0 l- w5 w; x5 H
- 7 ?8 ]! L6 s' Q6 q4 `* ~) S* G
- BL __TI_auto_init ; Call TI auto init t I& e" X$ ]
8 m$ Y9 L3 V7 _7 s- ;- }$ g, r2 @& V6 ^6 U. D2 _( ]9 a: P
- ; Enter the start_boot function. The execution still happens in system mode
3 V$ q" ?' o6 ? - ;
3 S) z' B ^& a8 t% b9 f) W - LDR r10, _start_boot ; Get the address of start_boot4 o% l% j) B. t9 A2 _
- MOV lr,pc ; Dummy return
4 v2 V! m( L- G7 |# E/ U - BX r10 ; Branch to start_boot
6 g/ L; ?7 a0 t, z - SUB pc, pc, #0x08 ; looping
) I; `& `1 r) r* C: o0 G7 x
! I& Y" c/ g& A: f0 h- ; MSR cpsr_c, #MODE_SVC|I_F_BIT ; change to SVC mode
& R6 Y) N, G9 z6 Z - ; BX lr
8 U2 G3 T* t4 `0 {( Y% R - ;! `0 |7 h1 I! ~$ a t" T7 K$ b3 ~
- ; End of the file/ Z) l; H; X0 o7 O7 _
- ;! W4 y$ c3 B) U) H) d, I
- E9 `( m4 r, X5 }% v3 m% g- _stackptr:
' L' u4 t; s1 h& g - .word __STACK_END
" I/ Q. r% F: i: L7 Y - _bss_start:
9 K7 ]: u+ x* T3 s/ w - .word bss_start3 d0 f) Z( {2 \4 L! V1 B, C* A
- _bss_end:
# |0 I( N/ r9 p, O6 x0 z - .word bss_end# o: n' P3 \" P
- _start_boot:
( P1 Q; G: D5 N* H- p0 C - .word start_boot6 C9 a6 r0 X5 [
- _data_auto_init:2 _4 c: A: k2 }
- .word __TI_auto_init
' ^( r! c) z: \3 P, q - .end
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9 M8 K' j0 Z. z" X; V
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复制代码
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