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sigh, I have a bootloader working!

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This commit is contained in:
David Welch
2012-05-27 02:31:05 -04:00
parent d69e19201f
commit c44c1146ea
11 changed files with 931 additions and 0 deletions
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257
bootloader01/bootloader01.c Normal file
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//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
extern void PUT32 ( unsigned int, unsigned int );
extern void PUT16 ( unsigned int, unsigned int );
extern unsigned int GET32 ( unsigned int );
extern void BRANCHTO ( unsigned int );
extern void dummy ( unsigned int );
#define GPFSEL1 0x20200004
#define GPSET0 0x2020001C
#define GPCLR0 0x20200028
#define GPPUD 0x20200094
#define GPPUDCLK0 0x20200098
#define AUX_ENABLES 0x20215004
#define AUX_MU_IO_REG 0x20215040
#define AUX_MU_IER_REG 0x20215044
#define AUX_MU_IIR_REG 0x20215048
#define AUX_MU_LCR_REG 0x2021504C
#define AUX_MU_MCR_REG 0x20215050
#define AUX_MU_LSR_REG 0x20215054
#define AUX_MU_MSR_REG 0x20215058
#define AUX_MU_SCRATCH 0x2021505C
#define AUX_MU_CNTL_REG 0x20215060
#define AUX_MU_STAT_REG 0x20215064
#define AUX_MU_BAUD_REG 0x20215068
//GPIO14 TXD0 and TXD1
//GPIO15 RXD0 and RXD1
//------------------------------------------------------------------------
unsigned int uart_recv ( void )
{
while(1)
{
if(GET32(AUX_MU_LSR_REG)&0x01) break;
}
return(GET32(AUX_MU_IO_REG)&0xFF);
}
//------------------------------------------------------------------------
void uart_send ( unsigned int c )
{
while(1)
{
if(GET32(AUX_MU_LSR_REG)&0x20) break;
}
PUT32(AUX_MU_IO_REG,c);
}
//------------------------------------------------------------------------
void hexstrings ( unsigned int d )
{
//unsigned int ra;
unsigned int rb;
unsigned int rc;
rb=32;
while(1)
{
rb-=4;
rc=(d>>rb)&0xF;
if(rc>9) rc+=0x37; else rc+=0x30;
uart_send(rc);
if(rb==0) break;
}
uart_send(0x20);
}
//------------------------------------------------------------------------
void hexstring ( unsigned int d )
{
hexstrings(d);
uart_send(0x0D);
uart_send(0x0A);
}
//------------------------------------------------------------------------
// Packet Format
// [0] 0x7C start sync
// [1] datalen
// [2] ~datalen
// datalen bytes:
// [3] type
// [4] sequence
// [5] pass=0/fail!=0
// [6]
// [7]
// [8] payload starts
// ...
// datalen ends
// [n-2] 0x7D end sync
// [n-1] checksum
//------------------------------------------------------------------------
unsigned char xstring[512];
//------------------------------------------------------------------------
int recv_packet ( void )
{
unsigned int len;
unsigned int ra;
unsigned int rb;
unsigned int rc;
while(1)
{
ra=uart_recv();
if(ra!=0x7C)
{
continue;
}
ra=0;
xstring[ra++]=0x7C; //sync
xstring[ra++]=uart_recv(); //datalen
xstring[ra++]=uart_recv(); //~datalen
if(xstring[ra-2]!=(~xstring[ra-1]&0xFF))
{
continue;
}
len=xstring[ra-2];
while(len--) xstring[ra++]=uart_recv();
xstring[ra++]=uart_recv(); //sync
xstring[ra++]=uart_recv(); //checksum
if(xstring[ra-2]!=0x7D)
{
continue;
}
for(rb=0,rc=0x00;rb<ra;rb++) rc+=xstring[rb];
rc&=0xFF;
if(rc==0xFF) break;
}
return(0);
}
//------------------------------------------------------------------------
int send_result ( unsigned char res )
{
unsigned int ra;
unsigned int rb;
unsigned int rc;
ra=0;
xstring[ra++]=0x7C; //xstring[ra++]=0x7C; //sync
xstring[ra++]=0x05; //xstring[ra++]=uart_recv(); //datalen
xstring[ra++]=~0x05;//xstring[ra++]=uart_recv(); //~datalen
//datalen:
ra++; //same as input
ra++; //same as input
xstring[ra++]=res;
xstring[ra++]=0;
xstring[ra++]=0;
//datalen
xstring[ra++]=0x7D;
for(rb=0,rc=0;rb<ra;rb++) rc+=xstring[rb];
xstring[ra++]=(~rc)&0xFF;
for(rb=0;rb<ra;rb++) uart_send(xstring[rb]);
return(0);
}
//------------------------------------------------------------------------
int notmain ( void )
{
unsigned int ra;
unsigned int len;
unsigned int addr;
unsigned int data;
PUT32(AUX_ENABLES,1);
PUT32(AUX_MU_IER_REG,0);
PUT32(AUX_MU_CNTL_REG,0);
PUT32(AUX_MU_LCR_REG,3);
PUT32(AUX_MU_MCR_REG,0);
PUT32(AUX_MU_IER_REG,0);
PUT32(AUX_MU_IIR_REG,0xC6);
PUT32(AUX_MU_BAUD_REG,270);
ra=GET32(GPFSEL1);
ra&=~(7<<12); //gpio14
ra|=2<<12; //alt5
ra&=~(7<<15); //gpio15
ra|=2<<15; //alt5
PUT32(GPFSEL1,ra);
PUT32(GPPUD,0);
for(ra=0;ra<150;ra++) dummy(ra);
PUT32(GPPUDCLK0,(1<<14)|(1<<15));
for(ra=0;ra<150;ra++) dummy(ra);
PUT32(GPPUDCLK0,0);
PUT32(AUX_MU_CNTL_REG,3);
hexstring(0x12345678);
while(1)
{
if(recv_packet()) break;
switch(xstring[3])
{
case 0x07: //write to ram
{
//validate len
len=xstring[1];
if(len<(5+4+2))
{
send_result(1);
break;
}
if((len-5-4-2)&1)
{
send_result(1);
break;
}
//[5,6,7,8,9] packet header
//[8,9,10,11] address
//[12,13] first halfword
//[14,15] second halfword
ra=8;
addr=0;
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
len-=5+4;
while(len)
{
data=0;
data<<=8; data|=xstring[ra++];
data<<=8; data|=xstring[ra++];
PUT16(addr,data);
addr+=2;
len-=2;
}
send_result(0);
break;
}
case 0x08: //branch to address
{
//validate len
len=xstring[1];
if(len!=(5+4))
{
send_result(1);
break;
}
//[5,6,7,8,9] packet header
//[8,9,10,11] address
ra=8;
addr=0;
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
addr<<=8; addr|=xstring[ra++];
send_result(0);
BRANCHTO(addr);
break;
}
}
}
return(0);
}
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------