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#define ASSEMBLY 1
.text
#include "convert.h"
.globl _start
.proc _start
_start:
alloc loc0=ar.pfs,1,2,3,0 /* in, local, out, rotating */
mov loc1=rp
mov r14=ip /* Get the address of _start, I'm in the first bundle */
movl r15=@gprel(_start)
;;
sub gp=r14,r15 /* gp = _start - @gprel(_start), current value of gp */
;;
mov out0=in0
mov out1=r28
add out2=@gprel(params),gp
br.call.sptk.few rp=convert_params
mov r28=r8
add r15=@gprel(entry), gp
;;
ld8 r16=[r15]
;;
mov b1=r16
mov ar.pfs=loc0
mov rp=loc1
;;
br.cond.sptk.few b1
.size _start, . - _start
.endp _start
#if 0
/* Base Address */
#define UART_BASE 0x00000000f8030000
#define UART_BAUD 9600
/* Data */
#define UART_RBR 0x00
#define UART_TBR 0x00
/* Control */
#define UART_IER 0x01
#define UART_IIR 0x02
#define UART_FCR 0x02
#define UART_LCR 0x03
#define UART_MCR 0x04
#define UART_DLL 0x00
#define UART_DLM 0x01
/* Status */
#define UART_LSR 0x05
#define UART_MSR 0x06
#define UART_SCR 0x07
#define UART_PHYS_BASE (0x8000000000000000|UART_BASE)
#define UART_DIV (115200/UART_BAUD)
#define UART_DIV_LO (UART_DIV&0xFF)
#define UART_DIV_HI ((UART_DIV >> 8)&0xFF)
#if ((115200%UART_BAUD) != 0)
#error Bad uart baud rate
#endif
/* NOTE: As these are debugging functions, they do not consume any
* space on the register stack, and instead rely entirely on
* scratch registers for the registers they use.
*/
uart_init:
/* set the UART_BASE */
movl r31=UART_PHYS_BASE
;;
/* disable interrupts */
add r30=UART_IER,r31
mov r29=0x00
;;
st1 [r30]=r29
/* enable fifos */
add r30=UART_FCR,r31
mov r29=0x01
;;
st1 [r30]=r29
/* Set Baud Rate Divisor to UART_BAUD */
add r30=UART_LCR,r31
mov r29=0x83
;;
st1 [r30]=r29
add r30=UART_DLL,r31
mov r29=UART_DIV_LO
;;
st1 [r30]=r29
add r30=UART_DLM,r31
mov r29=UART_DIV_HI
;;
st1 [r30]=r29
add r30=UART_LCR,r31
mov r29=0x03
;;
st1 [r30]=r29
br.ret.sptk.few rp
.proc uart_tx_byte
.globl uart_tx_byte
uart_tx_byte:
/* set the UART_PHYS_BASE */
movl r31=UART_PHYS_BASE
;;
__uart_tx_byte:
/* Wait until the UART can hold another byte */
add r30=UART_LSR,r31
;;
9: ld1.acq.nta r29=[r30]
;;
and r29=0x20,r29
;;
cmp.eq p63,p0=0,r29
(p63) br.cond.sptk.few 9b
/* Transmit the byte */
add r30=UART_TBR,r31
;;
st1.rel.nta [r30]=r32
;;
/* Wait until the UART is empty to be certain the byte is flushed */
add r30=UART_LSR,r31
;;
9: ld1.acq.nta r29=[r30]
;;
and r29=0x40,r29
;;
cmp.eq p63,p0=0,r29
(p63) br.cond.sptk.few 9b
;;
br.ret.sptk.few rp
.endp uart_tx_byte
__uart_tx_hex_char:
cmp.ltu p62,p63=9,r32
;;
(p63) add r32=48,r32 /* digits*/
(p62) add r32=55,r32 /* letters */
br.cond.sptk.few __uart_tx_byte
uart_tx_hex64:
/* set the UART_bASE */
movl r31=UART_PHYS_BASE
/* skip r28 */
mov r27=rp
mov r26=ar.pfs
mov r25=r32
;;
extr.u r32=r25,60,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,56,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,52,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,48,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,44,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,40,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,36,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,32,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,28,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,24,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,20,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,16,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,12,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,8,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,4,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
extr.u r32=r25,0,4
br.call.sptk.few rp=__uart_tx_hex_char
;;
mov ar.pfs = r26
mov rp = r27
;;
br.ret.sptk.few rp
#endif
.section ".trailer", "a"
/* Constants set at build time, these are at the very end of my image */
.balign 16
.global params
params:
convert_magic:
.quad CONVERT_MAGIC
entry:
.quad 0
initrd_start:
.quad 0
initrd_size:
.quad 0
cmdline:
.asciz "BOOT_IMAGE=head.S console=ttyS0 ip=dhcp root=/dev/nfs"
.org cmdline + 1024, 0
cmdline_end:
|
