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|
/*
* Most of this taken from Redboot hal_platform_setup.h with cleanup
*
* NOTE: I haven't clean this up considerably, just enough to get it
* running. See hal_platform_setup.h for the source. See
* board/cradle/memsetup.S for another PXA250 setup that is
* much cleaner.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <config.h>
#include <version.h>
#include <asm/arch/pxa-regs.h>
DRAM_SIZE: .long CFG_DRAM_SIZE
/* wait for coprocessor write complete */
.macro CPWAIT reg
mrc p15,0,\reg,c2,c0,0
mov \reg,\reg
sub pc,pc,#4
.endm
.globl memsetup
memsetup:
mov r10, lr
/* Set up GPIO pins first */
ldr r0, =GPSR0
ldr r1, =CFG_GPSR0_VAL
str r1, [r0]
ldr r0, =GPSR1
ldr r1, =CFG_GPSR1_VAL
str r1, [r0]
ldr r0, =GPSR2
ldr r1, =CFG_GPSR2_VAL
str r1, [r0]
ldr r0, =GPCR0
ldr r1, =CFG_GPCR0_VAL
str r1, [r0]
ldr r0, =GPCR1
ldr r1, =CFG_GPCR1_VAL
str r1, [r0]
ldr r0, =GPCR2
ldr r1, =CFG_GPCR2_VAL
str r1, [r0]
ldr r0, =GPDR0
ldr r1, =CFG_GPDR0_VAL
str r1, [r0]
ldr r0, =GPDR1
ldr r1, =CFG_GPDR1_VAL
str r1, [r0]
ldr r0, =GPDR2
ldr r1, =CFG_GPDR2_VAL
str r1, [r0]
ldr r0, =GAFR0_L
ldr r1, =CFG_GAFR0_L_VAL
str r1, [r0]
ldr r0, =GAFR0_U
ldr r1, =CFG_GAFR0_U_VAL
str r1, [r0]
ldr r0, =GAFR1_L
ldr r1, =CFG_GAFR1_L_VAL
str r1, [r0]
ldr r0, =GAFR1_U
ldr r1, =CFG_GAFR1_U_VAL
str r1, [r0]
ldr r0, =GAFR2_L
ldr r1, =CFG_GAFR2_L_VAL
str r1, [r0]
ldr r0, =GAFR2_U
ldr r1, =CFG_GAFR2_U_VAL
str r1, [r0]
/* enable GPIO pins */
ldr r0, =PSSR
ldr r1, =CFG_PSSR_VAL
str r1, [r0]
ldr r3, =MSC1 /* low - bank 2 Lubbock Registers / SRAM */
ldr r2, =CFG_MSC1_VAL /* high - bank 3 Ethernet Controller */
str r2, [r3] /* need to set MSC1 before trying to write to the HEX LEDs */
ldr r2, [r3] /* need to read it back to make sure the value latches (see MSC section of manual) */
ldr r1, =LED_BLANK
mov r0, #0xFF
str r0, [r1] /* turn on hex leds */
loop:
ldr r0, =0xB0070001
ldr r1, =_LED
str r0, [r1] /* hex display */
/*********************************************************************
Initlialize Memory Controller
The sequence below is based on the recommended init steps detailed
in the EAS, chapter 5 (Chapter 10, Operating Systems Developers Guide)
pause for 200 uSecs- allow internal clocks to settle
*Note: only need this if hard reset... doing it anyway for now
*/
@ ---- Wait 200 usec
ldr r3, =OSCR @ reset the OS Timer Count to zero
mov r2, #0
str r2, [r3]
ldr r4, =0x300 @ really 0x2E1 is about 200usec, so 0x300 should be plenty
1:
ldr r2, [r3]
cmp r4, r2
bgt 1b
mem_init:
@ get memory controller base address
ldr r1, =MEMC_BASE
@****************************************************************************
@ Step 1
@
@ write msc0, read back to ensure data latches
@
ldr r2, =CFG_MSC0_VAL
str r2, [r1, #MSC0_OFFSET]
ldr r2, [r1, #MSC0_OFFSET]
@ write msc1
ldr r2, =CFG_MSC1_VAL
str r2, [r1, #MSC1_OFFSET]
ldr r2, [r1, #MSC1_OFFSET]
@ write msc2
ldr r2, =CFG_MSC2_VAL
str r2, [r1, #MSC2_OFFSET]
ldr r2, [r1, #MSC2_OFFSET]
@ write mecr
ldr r2, =CFG_MECR_VAL
str r2, [r1, #MECR_OFFSET]
@ write mcmem0
ldr r2, =CFG_MCMEM0_VAL
str r2, [r1, #MCMEM0_OFFSET]
@ write mcmem1
ldr r2, =CFG_MCMEM1_VAL
str r2, [r1, #MCMEM1_OFFSET]
@ write mcatt0
ldr r2, =CFG_MCATT0_VAL
str r2, [r1, #MCATT0_OFFSET]
@ write mcatt1
ldr r2, =CFG_MCATT1_VAL
str r2, [r1, #MCATT1_OFFSET]
@ write mcio0
ldr r2, =CFG_MCIO0_VAL
str r2, [r1, #MCIO0_OFFSET]
@ write mcio1
ldr r2, =CFG_MCIO1_VAL
str r2, [r1, #MCIO1_OFFSET]
@-------------------------------------------------------
@ 3rd bullet, Step 1
@
@ get the mdrefr settings
ldr r3, =CFG_MDREFR_VAL_100
@ extract DRI field (we need a valid DRI field)
@
ldr r2, =0xFFF
@ valid DRI field in r3
@
and r3, r3, r2
@ get the reset state of MDREFR
@
ldr r4, [r1, #MDREFR_OFFSET]
@ clear the DRI field
@
bic r4, r4, r2
@ insert the valid DRI field loaded above
@
orr r4, r4, r3
@ write back mdrefr
@
str r4, [r1, #MDREFR_OFFSET]
@ *Note: preserve the mdrefr value in r4 *
@****************************************************************************
@ Step 2
@
/* This should be for SRAM, why is it commented out??? */
@ fetch sxcnfg value
@
@ldr r2, =0
@ write back sxcnfg
@str r2, [r1, #SXCNFG_OFFSET]
/* @if sxcnfg=0, don't program for synch-static memory */
@cmp r2, #0
@beq 1f
@program sxmrs
@ldr r2, =SXMRS_SETTINGS
@str r2, [r1, #SXMRS_OFFSET]
@****************************************************************************
@ Step 3
@
@ Assumes previous mdrefr value in r4, if not then read current mdrefr
@ clear the free-running clock bits
@ (clear K0Free, K1Free, K2Free
@
bic r4, r4, #(0x00800000 | 0x01000000 | 0x02000000)
@ set K1RUN if bank 0 installed
@
orr r4, r4, #0x00010000
#ifdef THIS
@<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<
@<!<!<!<!<!<!<!<!<!<!<! Begin INSERT 1 <!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ Lubbock: Allow the user to select the {T/R/M} with predetermined
@ SDCLK. Based on Table 3-1 in PXA250 and PXA210 Dev Man.
@
@ * = Must set MDREFR.K1DB2 to halve the MemClk for desired SDCLK[1]
@
@ S25, S26 used to provide all 400 MHz BIN values for Cotulla (0,0 - 1,3)
@ S25, S26 used to provide all 200 MHz BIN values for Sabinal
@
@ S23: Force the halving of MemClk when deriving SDCLK[1]
@ DOT: no override !DOT: halve (if not already forced half)
/* @ *For certain MemClks, SDCLK's derivation is forced to be halved */
@
@ S24: Run/Turbo.
@ DOT: Run mode !DOT: Turbo mode
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@
@ Allow the user to control K1DB2 where applicable
@
@ Get the value of S23: @ 1 = DOT (unity), 0 = !DOT (halve it)
@
@ DOT: set K1DB2 (SDCLD = MemClk)
@ !DOT: clear K1DB2 (SDCLK = MemClk/2)
@
@ldr r2, =FPGA_REGS_BASE_PHYSICAL
bl GET_S23 @ r3, r2 @ get the value of S23 in R0, i put the base adx of fpga in r3
cmp r3, #0x0 @ is !DOT?
orreq r4, r4, #0x00020000 @ SDClk[1] = MemClk/2
bicne r4, r4, #0x00020000 @ SDClk[1] = MemClk
@
@ Next, we need to look for S25,S26 selections that necessitate the
@ halving of MemClk to derive SDCLK[1]: (S25,S26)={03-0C, 10-13}
@ Override above S23-based selection accordingly.
@
ldr r2, =FPGA_REGS_BASE_PHYSICAL
bl GET_S25 @ r0, r2
@ get the value of S25 in R0, i put the base adx of fpga in r2
ldr r2, =FPGA_REGS_BASE_PHYSICAL
BL GET_S26 @ r3, r2
@ get the value of S26 in R1, i put the base adx of fpga in r2
orr r0, r0, r3 @ concatenate S25 & S26 vals
and r0, r0, #0xFF
@ Set K1DB2 for the frequencies that require it
@
cmp r0, #0x03
cmpne r0, #0x04
cmpne r0, #0x05
cmpne r0, #0x06
cmpne r0, #0x07
cmpne r0, #0x08
cmpne r0, #0x09
cmpne r0, #0x0A
cmpne r0, #0x0B
cmpne r0, #0x0C
cmpne r0, #0x10
cmpne r0, #0x11
cmpne r0, #0x12
cmpne r0, #0x13
orreq r4, r4, #0x00020000 @ SDCLK[1] = (MemClk)/2 for 03 - 0C @ 10 - 13
@
@ *Must make MSC0&1 adjustments now for MEMClks > 100MHz.
@
@ Adjust MSC0 for MemClks > 100 MHz
@
ldreq r0, [r1, #MSC0_OFFSET]
ldreq r3, =0x7F007F00
biceq r0, r0, r3 @ clear MSC0[14:12, 11:8] (RRR, RDN)
ldreq r3, =0x46004600
orreq r0, r0, r3 @ set MSC0[14, 10:9] (doubling RRR, RDN)
streq r0, [r1, #MSC0_OFFSET]
ldreq r0, [r1, #MSC0_OFFSET] @ read it back to ensure that the data latches
@
@ Adjust MSC1.LH for MemClks > 100 MHz
@
ldreq r0, [r1, #MSC1_OFFSET]
ldreq r3, =0x7FF0
biceq r0, r0, r3 @ clear MSC1[14:12, 11:8, 7:4] (RRR, RDN, RDF)
ldreq r3, =0x4880
orreq r0, r0, r3 @ set MSC1[14, 11, 7] (doubling RRR, RDN, RDF)
streq r0, [r1, #MSC1_OFFSET]
ldreq r0, [r1, #MSC1_OFFSET] @ read it back to ensure that the data latches
@ @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
#endif
@<!<!<!<!<!<!<!<!<!<!<! End INSERT 1 <!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<
@<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<!<
@ write back mdrefr
@
str r4, [r1, #MDREFR_OFFSET]
ldr r4, [r1, #MDREFR_OFFSET]
@ deassert SLFRSH
@
bic r4, r4, #0x00400000
@ write back mdrefr
@
str r4, [r1, #MDREFR_OFFSET]
@ assert E1PIN
@
orr r4, r4, #0x00008000
@ write back mdrefr
@
str r4, [r1, #MDREFR_OFFSET]
ldr r4, [r1, #MDREFR_OFFSET]
nop
nop
@****************************************************************************
@ Step 4
@
@ fetch platform value of mdcnfg
@
ldr r2, =CFG_MDCNFG_VAL
@ disable all sdram banks
@
bic r2, r2, #(MDCNFG_DE0 | MDCNFG_DE1)
bic r2, r2, #(MDCNFG_DE2 | MDCNFG_DE3)
@ program banks 0/1 for bus width
@
bic r2, r2, #MDCNFG_DWID0 @0=32-bit
@ write initial value of mdcnfg, w/o enabling sdram banks
@
str r2, [r1, #MDCNFG_OFFSET]
@ ****************************************************************************
@ Step 5
@
@ pause for 200 uSecs
@
ldr r3, =OSCR @reset the OS Timer Count to zero
mov r2, #0
str r2, [r3]
ldr r4, =0x300 @really 0x2E1 is about 200usec, so 0x300 should be plenty
1:
ldr r2, [r3]
cmp r4, r2
bgt 1b
@****************************************************************************
@ Step 6
@
mov r0, #0x78 @turn everything off
mcr p15, 0, r0, c1, c0, 0 @(caches off, MMU off, etc.)
@ ****************************************************************************
@ Step 7
@
@ Access memory *not yet enabled* for CBR refresh cycles (8)
@ - CBR is generated for all banks
ldr r2, =CFG_DRAM_BASE
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
@ ****************************************************************************
@ Step 8: NOP (enable dcache if you wanna... we dont)
@
@ ****************************************************************************
@ Step 9
@
@get memory controller base address
@
ldr r1, =MEMC_BASE
@fetch current mdcnfg value
@
ldr r3, [r1, #MDCNFG_OFFSET]
@enable sdram bank 0 if installed (must do for any populated bank)
@
orr r3, r3, #MDCNFG_DE0
@write back mdcnfg, enabling the sdram bank(s)
@
str r3, [r1, #MDCNFG_OFFSET]
@****************************************************************************
@ Step 10
@
@ write mdmrs
@
ldr r2, =CFG_MDMRS_VAL
str r2, [r1, #MDMRS_OFFSET]
@****************************************************************************
@ Step 11: Final Step
@
@INITINTC
@********************************************************************
@ Disable (mask) all interrupts at the interrupt controller
@
@ clear the interrupt level register (use IRQ, not FIQ)
@
mov r1, #0
ldr r2, =ICLR
str r1, [r2]
@ mask all interrupts at the controller
@
ldr r2, =ICMR
str r1, [r2]
@INITCLKS
@ ********************************************************************
@ Disable the peripheral clocks, and set the core clock
@ frequency (hard-coding at 398.12MHz for now).
@
@ Turn Off ALL on-chip peripheral clocks for re-configuration
@ *Note: See label 'ENABLECLKS' for the re-enabling
@
ldr r1, =CKEN
mov r2, #0
str r2, [r1]
@ default value in case no valid rotary switch setting is found
ldr r2, =(CCCR_L27 | CCCR_M2 | CCCR_N10) @ DEFAULT: {200/200/100}
@... and write the core clock config register
@
ldr r1, =CCCR
str r2, [r1]
/* @ enable the 32Khz oscillator for RTC and PowerManager
@
ldr r1, =OSCC
mov r2, #OSCC_OON
str r2, [r1]
@ NOTE: spin here until OSCC.OOK get set,
@ meaning the PLL has settled.
@
60:
ldr r2, [r1]
ands r2, r2, #1
beq 60b
*/
@OSCC_OON_DONE
#ifdef A0_COTULLA
@****************************************************************************
@ !!! Take care of A0 Errata Sighting #4 --
@ after a frequency change, the memory controller must be restarted
@
@ get memory controller base address
ldr r1, =MEMC_BASE
@ get the current state of MDREFR
@
ldr r2, [r1, #MDREFR_OFFSET]
@ clear E0PIN, E1PIN
@
bic r3, r2, #(MDREFR_E0PIN | MDREFR_E1PIN)
@ write MDREFR with E0PIN, E1PIN cleared (disable sdclk[0,1])
@
str r3, [r1, #MDREFR_OFFSET]
@ then write MDREFR with E0PIN, E1PIN set (enable sdclk[0,1])
@
str r2, [r1, #MDREFR_OFFSET]
@ get the current state of MDCNFG
@
ldr r3, [r1, #MDCNFG_OFFSET]
@ disable all SDRAM banks
@
bic r3, r3, #(MDCNFG_DE0 | MDCNFG_DE1)
bic r3, r3, #(MDCNFG_DE2 | MDCNFG_DE3)
@ write back MDCNFG
@
ldr r3, [r1, #MDCNFG_OFFSET]
@ Access memory not yet enabled for CBR refresh cycles (8)
@ - CBR is generated for *all* banks
ldr r2, =CFG_DRAM_BASE
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
str r2, [r2]
@ fetch current mdcnfg value
@
ldr r3, [r1, #MDCNFG_OFFSET]
@ enable sdram bank 0 if installed
@
orr r3, r3, #MDCNFG_DE0
@ write back mdcnfg, enabling the sdram bank(s)
@
str r3, [r1, #MDCNFG_OFFSET]
@ write mdmrs
@
ldr r2, =CFG_MDMRS_VAL
str r2, [r1, #MDMRS_OFFSET]
/* @ errata: don't enable auto power-down */
@ get current value of mdrefr
@ldr r3, [r1, #MDREFR_OFFSET]
@ enable auto-power down
@orr r3, r3, #MDREFR_APD
@write back mdrefr
@str r3, [r1, #MDREFR_OFFSET]
#endif A0_Cotulla
ldr r0, =0x000C0dE3
ldr r1, =_LED
str r0, [r1] /* hex display */
@ ^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%
@ ^%^%^%^%^%^%^%^%^% above could be replaced by prememLLI ^%^%^%^%^%^%^%^%^%
@ ^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%^%
/* Save SDRAM size */
ldr r1, =DRAM_SIZE
str r8, [r1]
ldr r0, =0xC0DE0006
ldr r1, =_LED
str r0, [r1] /* hex display */
/* Interrupt init */
/* Mask all interrupts */
ldr r0, =ICMR /* enable no sources */
mov r1, #0
str r1, [r0]
#define NODEBUG
#ifdef NODEBUG
/*Disable software and data breakpoints */
mov r0,#0
mcr p15,0,r0,c14,c8,0 /* ibcr0 */
mcr p15,0,r0,c14,c9,0 /* ibcr1 */
mcr p15,0,r0,c14,c4,0 /* dbcon */
/*Enable all debug functionality */
mov r0,#0x80000000
mcr p14,0,r0,c10,c0,0 /* dcsr */
#endif
ldr r0, =0xBEEF001D
ldr r1, =_LED
str r0, [r1] /* hex display */
mov pc, r10
@ End memsetup
@ %%%%%%%%%%% Useful subroutines
GET_S23:
@ This macro will read S23 and return its value in r3
@ r2 contains the base address of the Lubbock user registers
ldr r2, =FPGA_REGS_BASE_PHYSICAL
/*@ read S23's value */
ldr r3, [r2, #USER_SWITCHES_OFFSET]
@ mask out irrelevant bits
and r3, r3, #0x200
@ get bit into position 0
mov r3, r3, LSR #9
mov pc, lr
@ End GET_S23
GET_S24:
@ This macro will read S24 and return its value in r0
@ r2 contains the base address of the Lubbock user registers
ldr r2, =FPGA_REGS_BASE_PHYSICAL
/*@ read S24's value */
ldr r0, [r2, #USER_SWITCHES_OFFSET]
@ mask out irrelevant bits
and r0, r0, #0x100
@ get bit into position 0
mov r0, r0, LSR #8
mov pc, lr
@ End GET_S23
GET_S25:
@ This macro will read rotary S25 and return its value in r0
@ r2 contains the base address of the Lubbock user registers
@ read the user switches register
ldr r0, [r2, #USER_SWITCHES_OFFSET]
@ mask out irrelevant bits
and r0, r0, #0xF0
mov pc, lr
@ End subroutine
GET_S26:
@ This macro will read rotary S26 and return its value in r3
@ r2 contains the base address of the Lubbock user registers
@ read the user switches register
ldr r3, [r2, #USER_SWITCHES_OFFSET]
@ mask out irrelevant bits
and r3, r3, #0x0F
mov pc, lr
@ End subroutine GET_S26
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