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|
#include <ppc970.h>
/*----------------------------------------------------------------------------+
| Cycle counts ((1/ 9600)* 10) / (1/speed)) - 2%.
+----------------------------------------------------------------------------*/
#define SPEED_6_25 (0x0000196E- (65* 2))
#define SPEED_7_159 (0x00001D21- (74* 2))
#define SPEED_8_33 (0x000021E5- (86* 2))
#define SPEED_10_4 (0x00002A51- (108* 2))
#define SPEED_14_318 (0x00003A42- (149* 2))
#define SPEED_16_66 (0x000043D0- (173* 2))
#define SPEED_25 (0x000065B9- (260* 2))
#define SPEED_33 (0x000087A2- (347* 2))
#define SPEED_40 (0x0000A2C2- (416* 2))
#define SPEED_50 (0x0000CB73- (520* 2))
#define SPEED_66 (0x00010C8E- (687* 2))
#define SPEED_80 (0x00014585- (833* 2))
#define SPEED_100 (0x000196E6- (1041* 2))
#define SPEED_125 (0x0001FCA0- (1302* 2))
#define SPEED_133 (0x00021D2D- (1385* 2))
#define SPEED_150 (0x0002625A- (1562* 2))
#define SPEED_166 (0x0002A374- (1729* 2))
#define SPEED_175 (0x0002C813- (1822* 2))
#define SPEED_200 (0x00032DCD- (2093* 2))
#define SPEED_225 (0x00039387- (2343* 2))
#define SPEED_250 (0x0003F940- (2604* 2))
#define SPEED_275 (0x00045EFA- (2864* 2))
#define SPEED_300 (0x0004C4B4- (3125* 2))
#define SPEED_3375 (0x00055D4A- (3515* 2))
#define SPEED_375 (0x0005F5E1- (3906* 2))
#define SPEED_400 (0x00065B9A- (4166* 2))
#define SPEED_433 (0x0006E1E1- (4510* 2))
#define SPEED_466 (0x00076828- (4854* 2))
#define SPEED_500 (0x0007F281- (5208* 2))
/*----------------------------------------------------------------------------+
| Timebase_speed_calc
+----------------------------------------------------------------------------*/
function_prolog(timebase_speed_calc)
mfmsr r10
rlwinm r11,r10,0,17,15
mtmsrd r11,1
isync
/*--------------------------------------------------------------------+
| Make sure that all the characters in the transmit buffer are sent.
+--------------------------------------------------------------------*/
..sent: lbz r6,asyncLSR(r3)
andi. r6,r6,0x0060
cmpi cr0,1,r6,0x0060
bne ..sent
/*--------------------------------------------------------------------+
| Store current serial port settings in r11, r12.
| r11 BH (baud high), BL (baud low), LCR
| r12 MCR, IER, FCR
+--------------------------------------------------------------------*/
lbz r4,asyncLCR(r3)
ori r11,r4,0x0000
lbz r4,asyncFCR(r3)
ori r12,r4,0x0000
lbz r4,asyncIER(r3)
rlwimi r12,r4,8,16,23
lbz r4,asyncMCR(r3)
rlwimi r12,r4,16,8,15
/*--------------------------------------------------------------------+
| Store BH and BL and program new baud rate.
+--------------------------------------------------------------------*/
addi r4,r0,0x80
stb r4,asyncLCR(r3)
lbz r4,asyncDLABMsb(r3)
rlwimi r11,r4,16,8,15
addi r4,r0,DIV_HIGH_9600
stb r4,asyncDLABMsb(r3)
lbz r4,asyncDLABLsb(r3)
rlwimi r11,r4,8,16,23
addi r4,r0,DIV_LOW_9600
stb r4,asyncDLABLsb(r3)
addi r4,r0,0x03
stb r4,asyncLCR(r3)
/*--------------------------------------------------------------------+
| Put the serial port in loop-back mode.
+--------------------------------------------------------------------*/
addi r4,r0,0x00
stb r4,asyncFCR(r3)
stb r4,asyncIER(r3)
addi r4,r0,0x10
stb r4,asyncMCR(r3)
lbz r4,asyncRxBuffer(r3)
addi r4,r0,0x0041
/*--------------------------------------------------------------------+
| Again make sure there are no characters in transmit buffer.
+--------------------------------------------------------------------*/
addi r5,r0,0
..again:lbz r6,asyncLSR(r3)
andi. r6,r6,0x0060
cmpi cr0,1,r6,0x0060
bne ..again
/*--------------------------------------------------------------------+
| Take a snapshot of the timebase.
+--------------------------------------------------------------------*/
mfspr r7,tblr
/*--------------------------------------------------------------------+
| Send a character while in loopback mode. This will be done twice.
| Once to get the instuctions into I-cache, the second time for the
| real measurement.
+--------------------------------------------------------------------*/
stb r4,asyncTxBuffer(r3)
..spnlp:lbz r6,asyncLSR(r3)
andi. r6,r6,0x01
beq ..spnlp
mfspr r9,tblr
/*--------------------------------------------------------------------+
| Perform subtraction to determine how many timebase ticks it took
| to transmit the character.
+--------------------------------------------------------------------*/
subfc r9,r7,r9
/*--------------------------------------------------------------------+
| Consume the character sent in loopback mode.
+--------------------------------------------------------------------*/
lbz r4,asyncRxBuffer(r3)
eieio
/*--------------------------------------------------------------------+
| If the first character was just sent, go back and send a second.
+--------------------------------------------------------------------*/
cmpi cr0,1,r5,0x0000
addi r5,r5,1
beq ..again
/*--------------------------------------------------------------------+
| Restore serial port settings.
+--------------------------------------------------------------------*/
addi r4,r0,0x80
stb r4,asyncLCR(r3)
rlwinm r4,r11,16,24,31
stb r4,asyncDLABMsb(r3)
rlwinm r4,r11,24,24,31
stb r4,asyncDLABLsb(r3)
rlwinm r4,r11,0,24,31
stb r4,asyncLCR(r3)
rlwinm r4,r12,16,24,31
stb r4,asyncMCR(r3)
rlwinm r4,r12,24,24,31
stb r4,asyncIER(r3)
rlwinm r4,r12,0,24,31
stb r4,asyncFCR(r3)
/*--------------------------------------------------------------------+
| Calculate timebase speed (r9 is the time we are referencing).
+--------------------------------------------------------------------*/
addis r4,r0,SPEED_7_159@h
ori r4,r4,SPEED_7_159@l
cmp cr0,r9,r4
blt ..freq6
addis r4,r0,SPEED_8_33@h
ori r4,r4,SPEED_8_33@l
cmp cr0,r9,r4
blt ..freq7
addis r4,r0,SPEED_10_4@h
ori r4,r4,SPEED_10_4@l
cmp cr0,r9,r4
blt ..freq8
addis r4,r0,SPEED_14_318@h
ori r4,r4,SPEED_14_318@l
cmp cr0,r9,r4
blt ..freq10
addis r4,r0,SPEED_16_66@h
ori r4,r4,SPEED_16_66@l
cmp cr0,r9,r4
blt ..freq14
addis r4,r0,SPEED_25@h
ori r4,r4,SPEED_25@l
cmp cr0,r9,r4
blt ..freq16
addis r4,r0,SPEED_33@h
ori r4,r4,SPEED_33@l
cmp cr0,r9,r4
blt ..freq25
addis r4,r0,SPEED_40@h
ori r4,r4,SPEED_40@l
cmp cr0,r9,r4
blt ..freq33
addis r4,r0,SPEED_50@h
ori r4,r4,SPEED_50@l
cmp cr0,r9,r4
blt ..freq40
addis r4,r0,SPEED_66@h
ori r4,r4,SPEED_66@l
cmp cr0,r9,r4
blt ..freq50
addis r4,r0,SPEED_80@h
ori r4,r4,SPEED_80@l
cmp cr0,r9,r4
blt ..freq66
addis r4,r0,SPEED_100@h
ori r4,r4,SPEED_100@l
cmp cr0,r9,r4
blt ..freq80
addis r4,r0,SPEED_125@h
ori r4,r4,SPEED_125@l
cmp cr0,r9,r4
blt ..freq100
addis r4,r0,SPEED_133@h
ori r4,r4,SPEED_133@l
cmp cr0,r9,r4
blt ..freq125
addis r4,r0,SPEED_150@h
ori r4,r4,SPEED_150@l
cmp cr0,r9,r4
blt ..freq133
addis r4,r0,SPEED_166@h
ori r4,r4,SPEED_166@l
cmp cr0,r9,r4
blt ..freq150
addis r4,r0,SPEED_175@h
ori r4,r4,SPEED_175@l
cmp cr0,r9,r4
blt ..freq166
addis r4,r0,SPEED_200@h
ori r4,r4,SPEED_200@l
cmp cr0,r9,r4
blt ..freq175
addis r4,r0,SPEED_225@h
ori r4,r4,SPEED_225@l
cmp cr0,r9,r4
blt ..freq200
addis r4,r0,SPEED_250@h
ori r4,r4,SPEED_250@l
cmp cr0,r9,r4
blt ..freq225
addis r4,r0,SPEED_275@h
ori r4,r4,SPEED_275@l
cmp cr0,r9,r4
blt ..freq250
addis r4,r0,SPEED_300@h
ori r4,r4,SPEED_300@l
cmp cr0,r9,r4
blt ..freq275
addis r4,r0,SPEED_3375@h
ori r4,r4,SPEED_3375@l
cmp cr0,r9,r4
blt ..freq300
addis r4,r0,SPEED_375@h
ori r4,r4,SPEED_375@l
cmp cr0,r9,r4
blt ..freq3375
addis r4,r0,SPEED_400@h
ori r4,r4,SPEED_400@l
cmp cr0,r9,r4
blt ..freq375
addis r4,r0,SPEED_433@h
ori r4,r4,SPEED_433@l
cmp cr0,r9,r4
blt ..freq400
addis r4,r0,SPEED_466@h
ori r4,r4,SPEED_466@l
cmp cr0,r9,r4
blt ..freq433
addis r4,r0,SPEED_500@h
ori r4,r4,SPEED_500@l
cmp cr0,r9,r4
blt ..freq466
b ..freq500
..freq6:
addis r3,r0,0x005F
ori r3,r3,0x5e10
b ..end
..freq7:
addis r3,r0,0x006D
ori r3,r3,0x3CD8
b ..end
..freq8:
addis r3,r0,0x007F
ori r3,r3,0x2815
b ..end
..freq10:
addis r3,r0,0x009e
ori r3,r3,0xb100
b ..end
..freq14:
addis r3,r0,0x00da
ori r3,r3,0x79b0
b ..end
..freq16:
addis r3,r0,0x00fe
ori r3,r3,0x502A
b ..end
..freq25:
addis r3,r0,0x017D
ori r3,r3,0x7840
b ..end
..freq33:
addis r3,r0,0x01FC
ori r3,r3,0xA055
b ..end
..freq40:
addis r3,r0,0x0262
ori r3,r3,0x5A00
b ..end
..freq50:
addis r3,r0,0x02FA
ori r3,r3,0xF080
b ..end
..freq66:
addis r3,r0,0x03F9
ori r3,r3,0x40AA
b ..end
..freq80:
addis r3,r0,0x04C4
ori r3,r3,0xB400
b ..end
..freq100:
addis r3,r0,0x05F5
ori r3,r3,0xE100
b ..end
..freq125:
addis r3,r0,0x0773
ori r3,r3,0x5940
b ..end
..freq133:
addis r3,r0,0x07F2
ori r3,r3,0x8155
b ..end
..freq150:
addis r3,r0,0x08F0
ori r3,r3,0xD180
b ..end
..freq166:
addis r3,r0,0x09EF
ori r3,r3,0x21AA
b ..end
..freq175:
addis r3,r0,0x0A6E
ori r3,r3,0x49C0
b ..end
..freq200:
addis r3,r0,0x0BEB
ori r3,r3,0xC200
b ..end
..freq225:
addis r3,r0,0x0D69
ori r3,r3,0x3A40
b ..end
..freq250:
addis r3,r0,0x0EE6
ori r3,r3,0xB280
b ..end
..freq275:
addis r3,r0,0x1064
ori r3,r3,0x2AC0
b ..end
..freq300:
addis r3,r0,0x11E1
ori r3,r3,0xA300
b ..end
..freq3375:
addis r3,r0,0x141D
ori r3,r3,0xD760
b ..end
..freq375:
addis r3,r0,0x165A
ori r3,r3,0x0BC0
b ..end
..freq400:
addis r3,r0,0x17D7
ori r3,r3,0x8400
b ..end
..freq433:
addis r3,r0,0x19CF
ori r3,r3,0x0E40
b ..end
..freq466:
addis r3,r0,0x1BC6
ori r3,r3,0x9880
b ..end
..freq500:
addis r3,r0,0x1DCD
ori r3,r3,0x6500
..end: mtmsrd r10,1
isync
blr
function_epilog(timebase_speed_calc)
|
