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#ifndef CYGONCE_HAL_PLATFORM_SETUP_H

#define CYGONCE_HAL_PLATFORM_SETUP_H

/*=============================================================================

//

//      hal_platform_setup.h

//

//      Platform specific support for HAL (assembly code)

//

//=============================================================================

// ####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.

//

// eCos 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 or (at your option) any later

// version.

//

// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

//

// As a special exception, if other files instantiate templates or use

// macros or inline functions from this file, or you compile this file

// and link it with other works to produce a work based on this file,

// this file does not by itself cause the resulting work to be covered by

// the GNU General Public License. However the source code for this file

// must still be made available in accordance with section (3) of the GNU

// General Public License v2.

//

// This exception does not invalidate any other reasons why a work based

// on this file might be covered by the GNU General Public License.

// -------------------------------------------

// ####ECOSGPLCOPYRIGHTEND####

//=============================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):    msalter

// Contributors: gthomas

// Date:         2000-10-10

// Purpose:      Intel IOP310 platform specific support routines

// Description:

// Usage:       #include <cyg/hal/hal_platform_setup.h>

//

//####DESCRIPTIONEND####

//

//===========================================================================*/

#include <pkgconf/system.h>             // System-wide configuration info

#include <cyg/hal/hal_mmu.h>            // MMU definitions

#include <cyg/hal/hal_mm.h>             // More MMU definitions

#include CYGBLD_HAL_VARIANT_H           // Variant specific configuration

#include CYGBLD_HAL_PLATFORM_H          // Platform specific configuration

#include <cyg/hal/hal_iop310.h>         // Platform specific hardware definitions

// Define macro used to diddle the LEDs during early initialization.

// Can use r0+r1.  Argument in \x.

#define CYGHWR_LED_MACRO                 \

        b       667f                    ;\

   666:                                 ;\

        .byte   0xc0, 0xf9, 0xa4, 0xb0  ;\

        .byte   0x99, 0x92, 0x82, 0xf8  ;\

        .byte   0x80, 0x90, 0x88, 0x83  ;\

        .byte   0xa7, 0xa1, 0x86, 0x8e  ;\

   667:                                 ;\

        ldr     r0, =666b               ;\

        add     r0, r0, #\x             ;\

        ldrb    r1, [r0]                ;\

        ldr     r0, =DISPLAY_RIGHT      ;\

        str     r1, [r0]

#undef CYGHWR_LED_MACRO

// The main useful output of this file is PLATFORM_SETUP1: it invokes lots

// of other stuff (may depend on RAM or ROM start).  The other stuff is

// divided into further macros to make it easier to manage what's enabled

// when.

#if defined(CYG_HAL_STARTUP_ROM)

#define PLATFORM_SETUP1 _platform_setup1

//#define CYGHWR_HAL_ARM_HAS_MMU

#else

#define PLATFORM_SETUP1

#endif

#define RAM_BASE        0xa0000000

#define DRAM_SIZE       (512*1024*1024)         // max size of available SDRAM

#define DCACHE_SIZE     (32*1024)               // size of the Dcache

// Reserved area for battery backup SDRAM memory test

// This area is not zeroed out by initialization code

#define SDRAM_BATTERY_TEST_BASE         0xA1FFFFF0      // base address of last 16 memory locations in a 32MB SDRAM

        // Display 'lvalue:rvalue' on the hex display

        // lvalue and rvalue must be of the form 'DISPLAY_x'

        // where 'x' is a hex digit from 0-F.

        .macro HEX_DISPLAY reg0, reg1, lvalue, rvalue

        ldr     \reg0, =DISPLAY_LEFT            // display left digit

        ldr     \reg1, =\lvalue

        str     \reg1, [\reg0]

        ldr     \reg0, =DISPLAY_RIGHT

        ldr     \reg1, =\rvalue                 // display right digit

        str     \reg1, [\reg0]

        .endm

        // Trigger the logic analyzer by writing a particular

        // address, and triggering on that address.

        .macro TRIGGER_LA_ON_ADDRESS address, reg0, reg1

        mrc     p15, 0, \reg0, c1, c0, 0     // read ARM control register

        //      CPWAIT  \reg0

        ldr     \reg1, =\address

        str     \reg0, [\reg1]

        .endm

        // Delay a bit

        .macro DELAY_FOR cycles, reg0

        ldr     \reg0, =\cycles

        subs    \reg0, \reg0, #1

        subne   pc,  pc, #0xc

        .endm

        // wait for coprocessor write complete

        .macro CPWAIT reg

        mrc  p15,0,\reg,c2,c0,0

        mov  \reg,\reg

        sub  pc,pc,#4

        .endm

        // form a first-level section entry

        .macro FL_SECTION_ENTRY base,x,ap,p,d,c,b

        .word (\base << 20) | (\x << 12) | (\ap << 10) | (\p << 9) |\

              (\d << 5) | (\c << 3) | (\b << 2) | 2

        .endm

        // form a first-level page table entry

        .macro FL_PT_ENTRY base,p,d

        // I wanted to use logical operations here, but since I am using symbols later 

        // to fill in the parameters, I had to use addition to force the assembler to

        // do it right

        .word \base + (\p << 9) + (\d << 5) + 1

        .endm

        // form a second level small page entry

        .macro SL_SMPAGE_ENTRY base,ap3,ap2,ap1,ap0,c,b

        .word (\base << 12) | (\ap3 << 10) | (\ap2 << 8) | (\ap1 << 6) |\

              (\ap0 << 4) | (\c << 3) | (\b << 2) | 2

        .endm

        // form a second level extended small page entry

        .macro SL_XSMPAGE_ENTRY base,x,ap,c,b

        .word (\base << 12) | (\x << 6) | (\ap << 4) | (\c << 3) | (\b << 2) | 3

        .endm

        // start of platform setup

        .macro _platform_setup1

        // This is where we wind up immediately after reset. On the IOP310, we have

        // to jump around a hole in flash which runs from 0x00001000 - 0x0001fff.

        // The start of _platform_setup1 will be below 0x1000 and since we need to

        // align the mmu table on a 16k boundary, we just branch around the page

        // table which we will locate at FLASH_BASE+0x4000.

        b _real_platform_setup

        .p2align 13

        // the following alignment creates the mmu table at address 0x4000.

    mmu_table:

        // 1MB of FLASH with i80312 MMRs mapped in using 4K small pages so we can

        // set the access permission on flash and memory-mapped registers properly.

        FL_PT_ENTRY mmu_table_flashbase,0,0

        // Remaining 7MB of FLASH

        //   rw, cacheable, non-bufferable

        .set    __base,1

        .rept   7

        FL_SECTION_ENTRY __base,0,3,0,0,1,0

        .set    __base,__base+1

        .endr

        // nothing interesting here (Address Translation)

        .rept   0xA00 - 0x8

        FL_SECTION_ENTRY __base,0,3,0,0,0,0

        .set    __base,__base+1

        .endr

        // up to 512MB ECC SDRAM mapped 1-to-1

        // first 1MB mapped in 4K chunks

        //   x=c=b=1

        FL_PT_ENTRY mmu_table_rambase,1,0

        .set    __base,__base+1

        .rept   0xC00 - 0xA01

        FL_SECTION_ENTRY __base,1,3,1,0,1,1

        .set    __base,__base+1

        .endr

        // Cache flush region.

        // Don't need physical memory, just a cached area.

        .rept   0xD00 - 0xC00

        FL_SECTION_ENTRY __base,0,3,0,0,1,1

        .set    __base,__base+1

        .endr

        // Alias for first 1MB of FLASH

        //  rw, cacheable, non-bufferable

        FL_SECTION_ENTRY 0x000,0,3,0,0,1,0

        .set    __base,__base+1

        // Invalid

        .rept   0xE00 - 0xD01

        .word 0

        .set    __base,__base+1

        .endr

        // Uncached and unbuffered alias for first 256MB of SDRAM. This

        // area can be used by device drivers for DMA operations. Buffers

        // should be cache aligned.

        .set    __base,0xA00

        .rept   0xF00 - 0xE00

        FL_SECTION_ENTRY __base,0,3,1,0,0,0

        .set    __base,__base+1

        .endr

        // only I/O at 0xFE8xxxxx

        .set    __base,0xF00

        .rept   0x1000 - 0xF00

        FL_SECTION_ENTRY __base,0,3,0,0,0,0

        .set    __base,__base+1

        .endr

        // Immediately after the above table (at 0x8000) is the

        // second level page table which breaks up the lowest 1MB

        // of physical memory into 4KB sized virtual pages. These

        // pages work around a hole in flash (0x1000-0x1fff) used

        // by the Yavapai companion chip internal registers.

    mmu_table_flashbase:

        // Virtual address 0 (Flash boot code).

        // Map 4k page at 0x00000000 virt --> 0xA0000000 physical

        // This allows us to have a writable vector table.

        //   Read-Write, cacheable, bufferable

        SL_XSMPAGE_ENTRY 0xa0000,1,3,1,1

        // Virtual address 0x1000 (Memory mapped registers)

        // Map 1-to-1, but don't cache or buffer

        //   Read-Write, non-cacheable, non-bufferable         

        .set    __base,1

        SL_SMPAGE_ENTRY __base,3,3,3,3,0,0

        .set    __base,__base+1

        // Virtual address 0x2000-0x100000 (remainder of flash1)

        //   Read-Write, cacheable, non-bufferable

        .rept   0x100 - 0x2

        SL_SMPAGE_ENTRY __base,3,3,3,3,1,0

        .set    __base,__base+1

        .endr

        // Now is the second level table for the first megabyte

        // of DRAM.

    mmu_table_rambase:

        // Map first meg of SDRAM

        //   Read-Write, cacheable, bufferable

        .set    __base,0xA0000

        .rept   0x100

        SL_XSMPAGE_ENTRY __base,1,3,1,1

        .set    __base,__base+1

        .endr

_real_platform_setup:

        // Drain write and fill buffer

        mcr     p15,0,r0,c7,c10,4

        CPWAIT  r0

        // Disable write buffer coalescing

        mrc     p15,0,r0,c1,c0,1

        orr     r0,r0,#1                // set the disable bit

        mcr     p15,0,r0,c1,c0,1

        CPWAIT  r0

        // Delay appx 60 ms to let battery-backup reset complete

        DELAY_FOR 0x400000, r0

        // Eventually we will be able to check a register bit

        // to determine when this is complete 

        HEX_DISPLAY r0, r1, DISPLAY_0, DISPLAY_1

        //

        // ***  I2C interface initialization ***

        //

        //  Setup I2C Slave Address Register

        ldr     r1, =I2C_DEVID          // Load slave address r1.

        ldr     r2, =ISAR_ADDR          // Load address of the I2C Slave Address Register in r2.

        ldr     r3, =0x0000007f         // Load mask in r3.

        and     r1, r3, r3              // The mask zeroes the 25 MSBs of r1 just to make sure.

        str     r3, [r2]                // Save the value 0x02 (I2C_DEVID) in the register.

        //  Setup I2C Clock Count Register

        ldr     r2, =ICCR_ADDR          // Load the address of the I2C Clock Control Register in r2.

        ldr     r3, =0x0000014d         // Set for 5.05 us transition time at 66MHz (0x14D = 333).

        str     r3, [r2]                // Save the value in the register.

        //  Enable I2C Interface Unit - status will be polled

        ldr     r2, =ICR_ADDR           // Load the address of the Control Register in r2.

        ldr     r1, =ICR_GCALL          // Disable General Call (will be master)

        ldr     r3, =ICR_ENB            // Enable I2C unit ).

        orr     r1, r3, r1              // OR the two and store in R1

        ldr     r3, =ICR_SCLENB         // Enable I2C Clock Generator disabled

        orr     r1, r3, r1              // OR the two and store in R1

        str     r1, [r2]                // Save the value to the Control Register.

        //

        //  *** Now read the SPD Data ***

        //

        // Pointers to I2C Registers

        ldr     r11, =ICR_ADDR          // Load the address of the I2C Control Register in r11.

        ldr     r12, =ISR_ADDR          // Load the address of the I2C Status Register in r12.

        ldr     r13, =IDBR_ADDR         // Load the address of the I2C Data Buffer Register in r13.

        // Initialize byte counters

        ldr     r6, =0x00000000  // Counter incremented before byte is read

        ldr     r7, =0x00000040  // Number of bytes to read in the Presence Detect EEPROM of SDRAM: 64 bytes

        ldr     r5, =0x00000000  // R5 has running checksum calculation

        ldr     r9, =I2C_TIMOUT  // Timeout limit in case EEPROM does not respond

        // At the end of all this, R4 has DRAM size, R8 has bank count, and R10 has Bank size

        ldr     r10,=0x00000000  // Bank size

        ldr     r8, =0x00000000  // Bank count

        ldr     r4, =0x00000000  // SDRAM size

        /*  FREE REGISTERS ARE R0 - R3 */

        // *** Put out address, with WRITE mode ***

        // Set SDRAM module address and write mode

        ldr     r1, =SDRAM_DEVID        // Load slave address for SDRAM module: 0xA2 (Presence Detect Data)

        bic     r1, r1, #IDBR_MODE      // Clear read bit (bit #0)

        str     r1, [r13]               // Store to data register

        // Initiate dummy write to set EEPROM pointer to 0

        ldr     r1, [r11]               // read the current Control Register value

        orr     r1, r1, #ICR_START      // Set start bit

        orr     r1, r1, #ICR_TRANSFER   // Set transfer bit - bit is self_clearing

        str     r1, [r11]               // Store to control register

        // Wait for transmit empty status

        ldr     r1, =0x00000000         // Initialize I2C timeout counter

    0:

        add     r1, r1, #1              // Increment I2C timeout counter (r1 = r1 + 1)

        cmp     r1, r9

        beq     i2c_error               // Kick out of SDRAM initialization if timeout occurs

        ldr     r0, [r12]               // Load I2C Status Reg into R0

        ands    r3, r0, #ISR_EMPTY      // Bit #6 is checked: IDBR Transmit Empty

        beq     0b

        str     r0, [r12]               // Write back status to clear

        // *** Write pointer register on EEPROM to 0x00000000 ***

        //  Set SDRAM module EEPROM address to 0

        ldr     r1, =0x00000000         // Load base address of SDRAM module EEPROM

        str     r1, [r13]               // Store to data register

        //  Send address to EEPROM

        ldr     r1, [r11]               // read the current Control Register value

        bic     r1, r1, #ICR_START      // No start bit (already started)

        orr     r1, r1, #ICR_TRANSFER   // Set transfer bit - bit is self_clearing

        str     r1, [r11]               // Store to control register

        // Wait for transmit empty status

        ldr     r1, =0x00000000         // Initialize I2C timeout counter

    0:

        add     r1, r1, #1              // Increment I2C timeout counter (r1 = r1 + 1)

        cmp     r1, r9

        beq     i2c_error               // Kick out of SDRAM initialization if timeout occurs

        ldr     r0, [r12]               // Load I2C Status Reg into R0 -  ld    (r12), r10

        ands    r3, r0, #ISR_EMPTY      // Bit #6 is checked: IDBR Transmit Empty

        beq     0b

        str     r0, [r12]               // Write back status to clear

        // *** Read SDRAM PD data ***

        // *** Put out address, with READ mode ***

        //  Set SDRAM module address and read mode

        ldr     r0, =SDRAM_DEVID        // Load slave address for SDRAM module (0xA2)

        orr     r1, r0, #IDBR_MODE      // Set read bit (bit #0)

        str     r1, [r13]               // Store to data register

        //  Send next read request

        ldr     r1, [r11]               // read the current Control Register value

        orr     r1, r1, #ICR_START      // Set start bit

        orr     r1, r1, #ICR_TRANSFER   // Set transfer bit - bit is self_clearing

        str     r1, [r11]               // Store to control register

        // Wait for transmit empty status

        ldr     r1, =0x00000000         // Initialize I2C timeout counter

    0:

        add     r1, r1, #1              // Increment I2C timeout counter (r1 = r1 + 1)

        cmp     r1, r9

        beq     i2c_error               // Kick out of SDRAM initialization if timeout occurs

        ldr     r0, [r12]               // Load I2C Status Reg into R0 -  ld    (r12), r10

        ands    r3, r0, #ISR_EMPTY      // Bit #6 is checked: IDBR Transmit Empty

        beq     0b

        str     r0, [r12]               // Write back status to clear

    sdram_loop:

        add     r6, r6, #1              // Increment byte counter

        // *** READ the next Byte!!! ***

        ldr     r1, [r11]               // read the current Control Register value

        bic     r1, r1, #ICR_START      // No start bit (already started)

        orr     r1, r1, #ICR_TRANSFER   // Set transfer bit - bit is self_clearing

        // we have to set NACK before reading the last bit

        cmp     r6, r7                  // r7 = 64 (decimal) so if r6 = 64, this is the last byte to be read

        bne     1f                      // If bytes left, skip ahead

        orr     r1, r1, #ICR_ACK        // Set NACK if this is the last byte

        orr     r1, r1, #ICR_STOP       // Set STOP if this is the last byte

    1:

        str     r1, [r11]               // Store to control register

        // Wait for read full status

        ldr     r1, =0x00000000         // Initialize I2C timeout counter

    0:

        add     r1, r1, #1              // Increment I2C timeout counter (r1 = r1 + 1)

        cmp     r1, r9

        beq     i2c_error               // Kick out of SDRAM initialization if timeout occurs

        ldr     r0, [r12]               // Load I2C Status Reg into R0

        ands    r3, r0, #ISR_FULL       // Bit #6 is checked: IDBR Transmit Empty

        beq     0b

        str     r0, [r12]               // Write back status to clear

        // Read the data byte

        ldr     r1, [r13]               // Read the byte

        ldr     r2, =CHECKSUM_BYTE

        cmp     r6, r2                  // is it the CHECKSUM byte???

        beq     1f

        add     r5, r5, r1              // Add it to the checksum if not the checksum byte

        bal     2f                      // skip checksum comparison

    1:

        ldr     r0, =0xff               // If this is the checksum byte, compare it

        and     r5, r5, r0              //      against the calculated checksum

        cmp     r1, r5

        bne     bad_checksum            // If no match, skip SDRAM controller initialization

    2:

        ldr     r2, =BANKCNT_BYTE       // Check for bank count byte

        cmp     r6, r2

        bne     1f

        mov     r8, r1                  // Store bank count

    1:

        ldr     r2, =BANKSZ_BYTE        // Check for bank size byte

        cmp     r6, r2

        bne     1f

        ldr     r2, =0x04               // Store bank size in Mbytes (shift left 2 bits)

        mul     r10, r1, r2

        mul     r2, r8, r10             // Multiply by bank count to get DRAM size in MB

        ldr     r0, =0x100000

        mul     r4, r2, r0              // Convert size to bytes  - r4 contains DRAM size in bytes

1:

        // Handle the SDRAM drive strength setup here since we are out of

        // temporary registers to hold the SDRAM width value until after

        // all of the SPD data has been read.  Using the value of r8 for

        // the Bank Count is allright here since the SPD specification states that

        // the Bank Count SPD byte is #5 and the SDRAM Width SPD byte is #13.

        ldr     r2, =SDRAM_WIDTH_BYTE   // Check for SDRAM width byte

        cmp     r6, r2

        bne     1f

        mov     r2, #0x10         // Check for data width of 16

        cmp     r1, r2

        bne     SDRAM_DRIVE_X8

        // Module is composed of x16 devices

        mov     r2, #0x02                       

        cmp     r2, r8          // do we have 2 banks???

        beq     SDRAM_DRIVE_2_BANK_X16

        // Module is composed of 1 Bank of x16 devices

        ldr     r1, =SDCR_ADDR          // point at SDRAM Control Register

        ldr     r2, =SDCR_1BANK_X16     // drive strength value

        str     r2, [r1]                // set value in SDCR

        b       1f

SDRAM_DRIVE_2_BANK_X16:

        // Module is composed of 2 Banks of x16 devices

        ldr     r1, =SDCR_ADDR          // point at SDRAM Control Register

        ldr     r2, =SDCR_2BANK_X16     // drive strength value

        str     r2, [r1]                // set value in SDCR

        b       1f

SDRAM_DRIVE_X8:

        // Module is composed of x8 devices

        mov     r2, #0x02                       

        cmp     r2, r8                  // do we have 2 banks???

        beq     SDRAM_DRIVE_2_BANK_X8

        // Module is composed of 1 Bank of x8 devices

        ldr     r1, =SDCR_ADDR          // point at SDRAM Control Register

        ldr     r2, =SDCR_1BANK_X8      // drive strength value

        str     r2, [r1]                // set value in SDCR

        b       1f

SDRAM_DRIVE_2_BANK_X8:

        // Module is composed of 2 Banks of x16 devices

        ldr     r1, =SDCR_ADDR          // point at SDRAM Control Register

        ldr     r2, =SDCR_2BANK_X8      // drive strength value

        str     r2, [r1]                // set value in SDCR

    1:

        // Continue reading bytes if not done

        cmp     r6, r7

        bne     sdram_loop

        b       i2c_disable

    bad_checksum:

        HEX_DISPLAY r2, r3, DISPLAY_7, DISPLAY_7

    i2c_error:

        // hit the leds if an error occurred

        HEX_DISPLAY r2, r3, DISPLAY_5, DISPLAY_5

    i2c_disable:

        //  Disable I2C Interface Unit

        ldr     r1, [r11]

        bic     r1, r1, #ICR_ENB        // Disable I2C unit

        bic     r1, r1, #ICR_SCLENB     // Disable I2C clock generator

        str     r1, [r11]               // Store to control register

        // ADD THIS???:

        //  cmpobne     1, g9, test_init

        // Skip SDRAM controller initialization if checksum test failed

        // *** SDRAM setup ***

        ldr     r9, =MMR_BASE           // get base of MMRs

        ldr     r0, =RAM_BASE           // Program SDRAM Base Address register

        str     r0, [r9, #SDBR_OFF]    

        // Set up bank 0 register

    CHECK_32MB:

        ldr     r1, =RAM_32MEG          // do we have 32 MB banks?

        cmp     r10, r1

        bne     CHECK_64MB

        ldr     r0, =SBR_32MEG          // Program SDRAM Bank0 Boundary register to 32 MB

        b       SET_BANK1

    CHECK_64MB:

        ldr     r1, =RAM_64MEG          // do we have 64 MB banks?

        cmp     r10, r1

        bne     CHECK_128MB

        ldr     r0, =SBR_64MEG          // Program SDRAM Bank0 Boundary register to 64 MB

        b       SET_BANK1

    CHECK_128MB:

        ldr     r1, =RAM_128MEG         // do we have 128 MB banks?

        cmp     r10, r1

        bne     CHECK_256MB

        ldr     r0, =SBR_128MEG         // Program SDRAM Bank0 Boundary register to 128 MB

        b       SET_BANK1

    CHECK_256MB:

        ldr     r1, =RAM_256MEG         // do we have 256 MB banks?

        cmp     r10, r1

        bne     dram_error

        ldr     r0, =SBR_256MEG         // Program SDRAM Bank0 Boundary register to 64 MB

        b       SET_BANK1

    SET_BANK1:

        str     r0, [r9, #SBR0_OFF]     // store SBR0

        ldr     r2, =0x02

        cmp     r2, r8                  // do we have 2 banks???

        bne     SDRAM_1_BANK

        add     r0, r0, r0              // SDRAM Bank1 Boundary register is double SBR0

        str     r0, [r9, #SBR1_OFF]

        b       END_DRAM_SIZE

    SDRAM_1_BANK:

        // SDRAM Bank1 Boundary register is same as SBR0 for 1 bank configuration

        str     r0, [r9, #SBR1_OFF]

        b       END_DRAM_SIZE

    END_DRAM_SIZE:

        b       init_dram

    dram_error:

        HEX_DISPLAY r2, r3, DISPLAY_F, DISPLAY_F

   init_dram:

        ldr     r0, =0                   // turn off refresh

        str     r0, [r9, #RFR_OFF]

        ldr     r0,   =MRS_NO_OP        // Issue NOP cmd to SDRAM

        str     r0, [r9, #SDIR_OFF]

        DELAY_FOR 0x4000, r0

        ldr     r0, =MRS_PRECHRG        // Issue 1 Precharge all

        str     r0, [r9, #SDIR_OFF]    

        DELAY_FOR 0x4000, r0

        ldr     r0, =MRS_AUTO_RFRSH     // Issue 1 Auto Refresh command

        str     r0, [r9, #SDIR_OFF]    

        DELAY_FOR 0x4000, r0

        ldr     r0, =MRS_AUTO_RFRSH

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #1

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #2

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #3

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #4

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #5

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #6

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #7

        str     r0, [r9, #SDIR_OFF]    // Auto Refresh #8

        ldr     r0, =MRS_CAS_LAT_2      // set the CAS latency

        str     r0, [r9, #SDIR_OFF]

        DELAY_FOR 0x4000, r0

        ldr     r0, =MRS_NORM_OP        // Issue a Normal Operation command

        str     r0, [r9, #SDIR_OFF]     

        ldr     r0, =RFR_INIT_VAL       // Program Refresh Rate register

        str     r0, [r9, #RFR_OFF]     

        // ldr   r0, =(FLASH_BASE :AND: &FFFF0000)

        // str   r0, [r10, #FEBR1_OFF]   ; Program Flash Bank1 Base Address register

        // ldr   r0, =(FLASH_SIZE :AND: &FFFF0000)

        // str   r0, [r10, #FBSR1_OFF]   ; Program Flash Bank1 Size register

        // ldr   r0, =FWSR0_INIT_VAL

        // str   r0, [r10, #FWSR0_OFF]   ; Program Flash Bank0 Wait State register

        // ldr   r0, =FWSR1_INIT_VAL

        // str   r0, [r10, #FWSR1_OFF]   ; Program Flash Bank1 Wait State register

        HEX_DISPLAY r0, r1, DISPLAY_0, DISPLAY_2

        // begin initializing the i80310

        // Enable access to all coprocessor registers

        ldr     r0, =0x2001                     // enable access to all coprocessors

        mcr     p15, 0, r0, c15, c1, 0

        mcr     p15, 0, r0, c7, c10, 4           // drain the write & fill buffers

        CPWAIT r0

        mcr     p15, 0, r0, c7, c7, 0             // flush Icache, Dcache and BTB

        CPWAIT r0

        mcr     p15, 0, r0, c8, c7, 0             // flush instuction and data TLBs

        CPWAIT r0

        // Enable the Icache

        mrc     p15, 0, r0, c1, c0, 0

        orr     r0, r0, #MMU_Control_I

        mcr     p15, 0, r0, c1, c0, 0

        CPWAIT  r0

        // Set the TTB register

        ldr     r0, =mmu_table

        mcr     p15, 0, r0, c2, c0, 0

        // Enable permission checks in all domains

        ldr     r0, =0x55555555

        mcr     p15, 0, r0, c3, c0, 0

        // Enable the MMU

        mrc     p15, 0, r0, c1, c0, 0

        orr     r0, r0, #MMU_Control_M

        orr     r0, r0, #MMU_Control_R

        mcr     p15, 0, r0, c1, c0, 0

        CPWAIT  r0

        mcr     p15, 0, r0, c7, c10, 4           // drain the write & fill buffers

        CPWAIT r0

        // Enable the Dcache

        mrc     p15, 0, r0, c1, c0, 0

        orr     r0, r0, #MMU_Control_C

        mcr     p15, 0, r0, c1, c0, 0

        CPWAIT  r0

        // Initialize branch target buffer

        BTB_INIT r0

        //  Battery Backup SDRAM Memory Test

        //  Move 4 byte Test Pattern into register prior to zeroing out

        //  contents of SDRAM locations

        ldr     r9, =SDRAM_BATTERY_TEST_BASE

        ldr     r10, [r9]

        IOP310_EARLY_PCI_SETUP  r0, r1, r4, 0x113C, 0x0700

        // scrub/init SDRAM if enabled/present

        ldr     r11, =RAM_BASE  // base address of SDRAM

        mov     r12, r4         // size of memory to scrub

        mov     r8,r4           // save DRAM size

        mov     r0, #0          // scrub with 0x0000:0000

        mov     r1, #0

        mov     r2, #0                          

        mov     r3, #0

        mov     r4, #0                                  

        mov     r5, #0

        mov     r6, #0                                  

        mov     r7, #0

    10: // fastScrubLoop

        subs    r12, r12, #32   // 32 bytes/line