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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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