commit da7c10f1af1e710db3abf8e85dab3bcd0e74ea0a
parent d0c9e5caf9cdb2f8365c1f108468811566814e4d
Author: Matsuda Kenji <info@mtkn.jp>
Date: Tue, 12 Mar 2024 07:09:49 +0900
add section flasgs
Diffstat:
5 files changed, 17 insertions(+), 15 deletions(-)
diff --git a/ex3/Makefile b/ex3/Makefile
@@ -2,7 +2,7 @@ CC = arm-none-eabi-gcc
AS = arm-none-eabi-as
LD = arm-none-eabi-ld
OBJCOPY = arm-none-eabi-objcopy
-OBJDUMP = arm-none-eabi-objdump
+OBJDUMP = arm-none-eabi-objdump -Mforce-thumb
BINCRC = ../tools/bincrc
BIN2UF2 = ../tools/bin2uf2
diff --git a/ex3/main.c b/ex3/main.c
@@ -2,8 +2,10 @@ void init(void);
int puts(char *);
void printh(void *);
void set_alarm(unsigned int);
+void proc0(void);
extern void proc0_start, proc0_size;
+extern char *msg0;
// A proc represents a process in execution.
typedef struct proc {
@@ -31,15 +33,8 @@ main(void) {
proc *p0 = (proc *) 0x20041000, *p1 = (proc *) 0x20041100; // sram5
- printh(&proc0_start);
- puts("a");
- printh(&proc0_size);
- puts("b");
-
memcpy((void *)0x20000000, (void *)&proc0_start, (long) &proc0_size);
- proc0();
-
- puts("c");
+ puts(msg0);
p0->r[13] = (void *) 0x20000100; // sp
p0->r[14] = (void *) 0xdeadbeef; // lr
diff --git a/ex3/memmap.ld b/ex3/memmap.ld
@@ -22,6 +22,7 @@ SECTIONS
.rodata : {
*(.rodata)
kernel_end = .;
+ . = ALIGN(4);
} > SRAM4 AT > FLASH
prog_start = LOADADDR(.text);
prog_size = kernel_end - kernel_start;
@@ -34,4 +35,3 @@ SECTIONS
*(.proc1)
} > SRAM AT > FLASH
}
-
diff --git a/ex3/proc.s b/ex3/proc.s
@@ -1,19 +1,23 @@
- .section .proc0
+ .align 1
+ .section .proc0, "a"
.global proc0
proc0:
ldr r0, msg0
bl puts
- bx lr
+ b proc0
+ .align 2
+ .global msg0
msg0:
.asciz "proc0"
- .section .proc1
+ .align 1
+ .section .proc1, "a"
.global proc1
proc1:
ldr r0, msg1
bl puts
b proc1
-
+ .align 2
msg1:
.asciz "proc1"
diff --git a/ex3/start.s b/ex3/start.s
@@ -249,7 +249,8 @@ memcpy_loop:
blt memcpy_loop
pop {r4, pc}
-
+ // void putbyte(char b);
+ // Putbyte writes b to uart0.
putbyte:
ldr r3, uart0_base
mov r1, #1
@@ -263,6 +264,8 @@ txff:
str r0, [r3, #0] // UART: UARTDR
bx lr
+ // char getbyte(void);
+ // Getbyte reads a byte from uart0.
getbyte:
ldr r3, uart0_base
mov r1, #1
