/* SPDX-License-Identifier: GPL-2.0 */
/*
 * linux/arch/arm/boot/compressed/head-sharpsl.S
 *
 * Copyright (C) 2004-2005 Richard Purdie <rpurdie@rpsys.net>
 *
 * Sharp's bootloader doesn't pass any kind of machine ID
 * so we have to figure out the machine for ourselves...
 *
 * Support for Poodle, Corgi (SL-C700), Shepherd (SL-C750)
 * Husky (SL-C760), Tosa (SL-C6000), Spitz (SL-C3000),
 * Akita (SL-C1000) and Borzoi (SL-C3100).
 *
 */

#include <linux/linkage.h>
#include <asm/mach-types.h>

#ifndef CONFIG_PXA_SHARPSL
#error What am I doing here...
#endif

                .section        ".start", "ax"

__SharpSL_start:

/* Check for TC6393 - if found we have a Tosa */
        ldr     r7, .TOSAID
        mov     r1, #0x10000000         @ Base address of TC6393 chip
        mov     r6, #0x03
        ldrh    r3, [r1, #8]            @ Load TC6393XB Revison: This is 0x0003
        cmp     r6, r3
        beq     .SHARPEND               @ Success -> tosa

/* Check for pxa270 - if found, branch */
        mrc p15, 0, r4, c0, c0          @ Get Processor ID
        and     r4, r4, #0xffffff00
        ldr     r3, .PXA270ID
        cmp     r4, r3
        beq     .PXA270

/* Check for w100 - if not found we have a Poodle */
        ldr     r1, .W100ADDR           @ Base address of w100 chip + regs offset

        mov r6, #0x31                   @ Load Magic Init value
        str     r6, [r1, #0x280]        @ to SCRATCH_UMSK
        mov r5, #0x3000
.W100LOOP:
        subs r5, r5, #1
        bne .W100LOOP
        mov r6, #0x30                   @ Load 2nd Magic Init value
        str     r6, [r1, #0x280]        @ to SCRATCH_UMSK

        ldr     r6, [r1, #0]            @ Load Chip ID
        ldr     r3, .W100ID
        ldr     r7, .POODLEID
        cmp     r6, r3
        bne     .SHARPEND                       @ We have no w100 - Poodle

/* Check for pxa250 - if found we have a Corgi */
        ldr     r7, .CORGIID
        ldr     r3, .PXA255ID
        cmp     r4, r3
        blo     .SHARPEND                       @ We have a PXA250 - Corgi

/* Check for 64MiB flash - if found we have a Shepherd */
        bl      get_flash_ids
        ldr     r7, .SHEPHERDID
        cmp     r3, #0x76                       @ 64MiB flash
        beq     .SHARPEND                       @ We have Shepherd

/* Must be a Husky */
        ldr     r7, .HUSKYID            @ Must be Husky
        b .SHARPEND

.PXA270:
/* Check for 16MiB flash - if found we have Spitz */
        bl      get_flash_ids
        ldr     r7, .SPITZID
        cmp     r3, #0x73                       @ 16MiB flash
        beq     .SHARPEND                       @ We have Spitz

/* Check for a second SCOOP chip - if found we have Borzoi */
        ldr     r1, .SCOOP2ADDR
        ldr     r7, .BORZOIID
        mov     r6, #0x0140
        strh    r6, [r1]
        ldrh    r6, [r1]
        cmp     r6, #0x0140
        beq     .SHARPEND                       @ We have Borzoi

/* Must be Akita */
        ldr     r7, .AKITAID
        b       .SHARPEND                       @ We have Borzoi

.PXA255ID:
        .word   0x69052d00              @ PXA255 Processor ID
.PXA270ID:
        .word   0x69054100              @ PXA270 Processor ID
.W100ID:
        .word   0x57411002              @ w100 Chip ID
.W100ADDR:
        .word   0x08010000              @ w100 Chip ID Reg Address
.SCOOP2ADDR:
        .word   0x08800040
.POODLEID:
        .word   MACH_TYPE_POODLE
.CORGIID:
        .word   MACH_TYPE_CORGI
.SHEPHERDID:
        .word   MACH_TYPE_SHEPHERD
.HUSKYID:
        .word   MACH_TYPE_HUSKY
.TOSAID:
        .word   MACH_TYPE_TOSA
.SPITZID:
        .word   MACH_TYPE_SPITZ
.AKITAID:
        .word   MACH_TYPE_AKITA
.BORZOIID:
        .word   MACH_TYPE_BORZOI

/*
 * Return: r2 - NAND Manufacturer ID
 *         r3 - NAND Chip ID
 * Corrupts: r1
 */
get_flash_ids:
        mov     r1, #0x0c000000         @ Base address of NAND chip
        ldrb    r3, [r1, #24]           @ Load FLASHCTL
        bic     r3, r3, #0x11           @ SET NCE
        orr     r3, r3, #0x0a           @ SET CLR + FLWP
        strb    r3, [r1, #24]           @ Save to FLASHCTL
        mov     r2, #0x90               @ Command "readid"
        strb    r2, [r1, #20]           @ Save to FLASHIO
        bic     r3, r3, #2              @ CLR CLE
        orr     r3, r3, #4              @ SET ALE
        strb    r3, [r1, #24]           @ Save to FLASHCTL
        mov     r2, #0                  @ Address 0x00
        strb    r2, [r1, #20]           @ Save to FLASHIO
        bic     r3, r3, #4              @ CLR ALE
        strb    r3, [r1, #24]           @ Save to FLASHCTL
.fids1:
        ldrb    r3, [r1, #24]           @ Load FLASHCTL
        tst     r3, #32                 @ Is chip ready?
        beq     .fids1
        ldrb    r2, [r1, #20]           @ NAND Manufacturer ID
        ldrb    r3, [r1, #20]           @ NAND Chip ID
        mov     pc, lr

.SHARPEND: