# SPDX-License-Identifier: GPL-2.0-or-later

# Embedded Artists eval board for LPC2478
# http://www.embeddedartists.com/

# Target device: LPC2478
set CCLK 72000
source [find target/lpc2478.cfg]

# Helper
#
proc read_register {register} {
    return [read_memory $register 32 1]
}

proc init_board {} {
    # Delays on reset lines
    adapter srst delay 500
    jtag_ntrst_delay 1

    # Adaptive JTAG clocking through RTCK.
    #
    jtag_rclk 20

    global _TARGETNAME
    global _CHIPNAME

    # A working area will help speeding the flash programming
    $_TARGETNAME configure -work-area-phys 0x40000200 -work-area-size [expr {0x10000-0x200-0x20}] -work-area-backup 0

    # External 16-bit flash at chip select CS0 (SST39VF3201-70, 4 MiB)
    flash bank $_CHIPNAME.extflash cfi 0x80000000 0x400000 2 2 $_TARGETNAME jedec_probe

    # Event handlers
    #
    $_TARGETNAME configure -event reset-start {
        # Back to the slow JTAG clock
        jtag_rclk 20
    }

    $_TARGETNAME configure -event reset-init {
        arm core_state arm
        arm7_9 dcc_downloads enable     ;# Speed up downloads by using DCC transfer
        arm7_9 fast_memory_access enable

        # Peripheral clocks
        mww 0xE01FC0C4 0x04280FFE       ;# PCONP: (reset value)

        # Map the user flash to the vector table area (0x00...0x3F)
        mww 0xE01FC040 0x00000001       ;# MEMMAP: User flash

        # Memory accelerator module
        mww 0xE01FC004 0x00000003       ;# MAMTIM: 3 clock cycles
        mww 0xE01FC000 0x00000002       ;# MAMCR: fully enabled

        # Enable external memory bus (32-bit SDRAM at DYCS0, 16-bit flash at CS0)
        mww 0xE002C014 0x55010115       ;# PINSEL5: P2.16=CAS, P2.17=RAS, P2.18=CLKOUT0,
                                         # P2.20=DYCS0, P2.24=CKEOUT0, P2.28=DQMOUT0,
                                         # P2.29=DQMOUT1, P2.30=DQMOUT2, P2.31=DQMOUT3
        mww 0xE002C018 0x55555555       ;# PINSEL6: P3.0...P3.15=D0...D15
        mww 0xE002C01C 0x55555555       ;# PINSEL7: P3.16...P3.31=D16...D31
        mww 0xE002C020 0x55555555       ;# PINSEL8: P4.0...P4.15=A0...A15
        mww 0xE002C024 0x50051555       ;# PINSEL9: P4.16...P4.22=A16...A22, P4.24=OE,
                                         # P4.25=WE, P4.30=CS0, P4.31=CS1
        mww 0xFFE08000 0x00000001       ;# EMCControl: Enable EMC

        # Start PLL, then use faster JTAG clock
        enable_pll
        jtag_rclk 3000

        # 16-bit flash @ CS0 (SST39VF3201-70)
        mww 0xFFE08200 0x00080081       ;# EMCStaticConfig0: 16 bit, PB=1, buffers on
        mww 0xFFE08204 0x00000000       ;# EMCStaticWaitWen0
        mww 0xFFE08208 0x00000000       ;# EMCStaticWaitOen0
        mww 0xFFE0820C 0x00000005       ;# EMCStaticWaitRd0
        mww 0xFFE08210 0x00000005       ;# EMCStaticWaitPage0
        mww 0xFFE08214 0x00000003       ;# EMCStaticWaitWr0
        mww 0xFFE08218 0x00000001       ;# EMCStaticWaitTurn0

        # 8-bit NAND @ CS1
        # TODO

        # 32-bit SDRAM @ DYCS0 (K4M563233G-HN75)
        mww 0xFFE08028 0x00000001       ;# EMCDynamicReadConfig
        mww 0xFFE08030 0x00000001       ;# EMCDynamicRP
        mww 0xFFE08034 0x00000003       ;# EMCDynamicRAS
        mww 0xFFE08038 0x00000005       ;# EMCDynamicSREX
        mww 0xFFE0803C 0x00000001       ;# EMCDynamicAPR
        mww 0xFFE08040 0x00000005       ;# EMCDynamicDAL
        mww 0xFFE08044 0x00000001       ;# EMCDynamicWR
        mww 0xFFE08048 0x00000005       ;# EMCDynamicRC
        mww 0xFFE0804C 0x00000005       ;# EMCDynamicRFC
        mww 0xFFE08050 0x00000005       ;# EMCDynamicXSR
        mww 0xFFE08054 0x00000001       ;# EMCDynamicRRD
        mww 0xFFE08058 0x00000001       ;# EMCDynamicMRD
        #
        mww 0xFFE08104 0x00000202       ;# EMCDynamicRasCas0
        mww 0xFFE08100 0x00005488       ;# EMCDynamicConfig0
        sleep 100
        mww 0xFFE08020 0x00000183       ;# EMCDynamicControl: Clock on continuously, NOP
        sleep 10
        mww 0xFFE08020 0x00000103       ;# EMCDynamicControl: PRECHARGE-ALL
        mww 0xFFE08024 0x00000046       ;# EMCDynamicRefresh
        sleep 100
        mww 0xFFE08020 0x00000083       ;# EMCDynamicControl: MODE
        mdw 0xA0011000 1                ;# Set SDRAM mode register
        mww 0xFFE08020 0x00000000       ;# EMCDynamicControl: NORMAL
        mww 0xFFE08100 0x00085488       ;# EMCDynamicConfig0: Enable buffers
    }

    $_TARGETNAME configure -event gdb-attach {
        # Without this gdb-attach will first time as probe will fail
        reset init
    }
}

# Enable the PLL.
# Generate maximum CPU clock (72 MHz) Run from internal RC oscillator.
# Note: The PLL output runs at a frequency N times the desired CPU clock.
#       It in unavoidable that the CPU clock drops down to (4 MHz/N) during
#       the initialization!
#       Here: N=4
#       Note that if the PLL is already active at the time this script is
#       called, the effective value of N is the value of CCLKCFG at that time!
#
proc enable_pll {} {
    # Disconnect PLL in case it is already connected
    if {[expr {[read_register 0xE01FC080] & 0x03}] == 3} {
        # Disconnect it, but leave it enabled
        # (This MUST be done in two steps)
        mww 0xE01FC080 0x00000001       ;# PLLCON: disconnect PLL
        mww 0xE01FC08C 0x000000AA       ;# PLLFEED
        mww 0xE01FC08C 0x00000055       ;# PLLFEED
    }
    # Disable PLL (as it might already be enabled at this time!)
    mww 0xE01FC080 0x00000000       ;# PLLCON: disable PLL
    mww 0xE01FC08C 0x000000AA       ;# PLLFEED
    mww 0xE01FC08C 0x00000055       ;# PLLFEED

    # Setup PLL to generate 288 MHz from internal RC oscillator
    mww 0xE01FC10C 0x00000000       ;# CLKSRCSEL: IRC
    mww 0xE01FC084 0x00000023       ;# PLLCFG: N=1, M=36
    mww 0xE01FC08C 0x000000AA       ;# PLLFEED
    mww 0xE01FC08C 0x00000055       ;# PLLFEED
    mww 0xE01FC080 0x00000001       ;# PLLCON: enable PLL
    mww 0xE01FC08C 0x000000AA       ;# PLLFEED
    mww 0xE01FC08C 0x00000055       ;# PLLFEED
    sleep 100
    mww 0xE01FC104 0x00000003       ;# CCLKCFG: divide by 4 (72 MHz)
    mww 0xE01FC080 0x00000003       ;# PLLCON: connect PLL
    mww 0xE01FC08C 0x000000AA       ;# PLLFEED
    mww 0xE01FC08C 0x00000055       ;# PLLFEED
}
