/*      $NetBSD: brh_machdep.c,v 1.56 2024/02/20 23:36:02 andvar Exp $  */

/*
 * Copyright (c) 2001, 2002, 2003 Wasabi Systems, Inc.
 * All rights reserved.
 *
 * Written by Jason R. Thorpe for Wasabi Systems, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed for the NetBSD Project by
 *      Wasabi Systems, Inc.
 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1997,1998 Mark Brinicombe.
 * Copyright (c) 1997,1998 Causality Limited.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Mark Brinicombe
 *      for the NetBSD Project.
 * 4. The name of the company nor the name of the author may be used to
 *    endorse or promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * Machine dependent functions for kernel setup for the ADI Engineering
 * BRH i80200 evaluation platform.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: brh_machdep.c,v 1.56 2024/02/20 23:36:02 andvar Exp $");

#include "opt_arm_debug.h"
#include "opt_console.h"
#include "opt_ddb.h"

#include <sys/param.h>
#include <sys/device.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/exec.h>
#include <sys/proc.h>
#include <sys/msgbuf.h>
#include <sys/reboot.h>
#include <sys/termios.h>
#include <sys/ksyms.h>
#include <sys/bus.h>
#include <sys/cpu.h>

#include <uvm/uvm_extern.h>

#include <dev/cons.h>

#include <machine/db_machdep.h>
#include <ddb/db_sym.h>
#include <ddb/db_extern.h>

#include <machine/bootconfig.h>
#include <arm/locore.h>
#include <arm/undefined.h>

#include <arm/arm32/machdep.h>

#include <arm/xscale/i80200reg.h>
#include <arm/xscale/i80200var.h>

#include <dev/pci/ppbreg.h>

#include <arm/xscale/beccreg.h>
#include <arm/xscale/beccvar.h>

#include <evbarm/adi_brh/brhreg.h>
#include <evbarm/adi_brh/brhvar.h>
#include <evbarm/adi_brh/obiovar.h>

#include "ksyms.h"

/* Kernel text starts 2MB in from the bottom of the kernel address space. */
#define KERNEL_TEXT_BASE        (KERNEL_BASE + 0x00200000)
#define KERNEL_VM_BASE          (KERNEL_BASE + 0x01000000)

/*
 * The range 0xc1000000 - 0xccffffff is available for kernel VM space
 * Core-logic registers and I/O mappings occupy 0xfd000000 - 0xffffffff
 */
#define KERNEL_VM_SIZE          0x0C000000

BootConfig bootconfig;          /* Boot config storage */
char *boot_args = NULL;
char *boot_file = NULL;

vaddr_t physical_start;
vaddr_t physical_freestart;
vaddr_t physical_freeend;
vaddr_t physical_end;
u_int free_pages;

/*int debug_flags;*/
#ifndef PMAP_STATIC_L1S
int max_processes = 64;                 /* Default number */
#endif  /* !PMAP_STATIC_L1S */

/* Physical and virtual addresses for some global pages */
pv_addr_t minidataclean;

paddr_t msgbufphys;

#define KERNEL_PT_SYS           0       /* L2 table for mapping zero page */

#define KERNEL_PT_KERNEL        1       /* L2 table for mapping kernel */
#define KERNEL_PT_KERNEL_NUM    2

                                        /* L2 tables for mapping kernel VM */
#define KERNEL_PT_VMDATA        (KERNEL_PT_KERNEL + KERNEL_PT_KERNEL_NUM)
#define KERNEL_PT_VMDATA_NUM    4       /* start with 16MB of KVM */
#define NUM_KERNEL_PTS          (KERNEL_PT_VMDATA + KERNEL_PT_VMDATA_NUM)

pv_addr_t kernel_pt_table[NUM_KERNEL_PTS];

/* Prototypes */

void    consinit(void);

#include "com.h"
#if NCOM > 0
#include <dev/ic/comreg.h>
#include <dev/ic/comvar.h>
#endif

/*
 * Define the default console speed for the board.  This is generally
 * what the firmware provided with the board defaults to.
 */
#ifndef CONSPEED
#define CONSPEED B57600
#endif /* ! CONSPEED */

#ifndef CONUNIT
#define CONUNIT 0
#endif

#ifndef CONMODE
#define CONMODE ((TTYDEF_CFLAG & ~(CSIZE | CSTOPB | PARENB)) | CS8) /* 8N1 */
#endif

int comcnspeed = CONSPEED;
int comcnmode = CONMODE;
int comcnunit = CONUNIT;

/*
 * void cpu_reboot(int howto, char *bootstr)
 *
 * Reboots the system
 *
 * Deal with any syncing, unmounting, dumping and shutdown hooks,
 * then reset the CPU.
 */
void
cpu_reboot(int howto, char *bootstr)
{

        /*
         * If we are still cold then hit the air brakes
         * and crash to earth fast
         */
        if (cold) {
                doshutdownhooks();
                pmf_system_shutdown(boothowto);
                printf("The operating system has halted.\n");
                printf("Please press any key to reboot.\n\n");
                cngetc();
                printf("rebooting...\n");
                goto reset;
        }

        /* Disable console buffering */

        /*
         * If RB_NOSYNC was not specified sync the discs.
         * Note: Unless cold is set to 1 here, syslogd will die during the
         * unmount.  It looks like syslogd is getting woken up only to find
         * that it cannot page part of the binary in as the filesystem has
         * been unmounted.
         */
        if (!(howto & RB_NOSYNC))
                bootsync();

        /* Say NO to interrupts */
        splhigh();

        /* Do a dump if requested. */
        if ((howto & (RB_DUMP | RB_HALT)) == RB_DUMP)
                dumpsys();

        /* Run any shutdown hooks */
        doshutdownhooks();

        pmf_system_shutdown(boothowto);

        /* Make sure IRQ's are disabled */
        IRQdisable;

        if (howto & RB_HALT) {
                brh_7seg('8');
                printf("The operating system has halted.\n");
                printf("Please press any key to reboot.\n\n");
                cngetc();
        }

        printf("rebooting...\n\r");
 reset:
        cpu_reset();
}

/* Static device mappings. */
static const struct pmap_devmap brh_devmap[] = {
    DEVMAP_ENTRY(
        BRH_PCI_CONF_VBASE,
        BECC_PCI_CONF_BASE,
        BRH_PCI_CONF_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_PCI_MEM1_VBASE,
        BECC_PCI_MEM1_BASE,
        BRH_PCI_MEM1_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_PCI_MEM2_VBASE,
        BECC_PCI_MEM2_BASE,
        BRH_PCI_MEM2_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_UART1_VBASE,
        BRH_UART1_BASE,
        BRH_UART1_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_UART2_VBASE,
        BRH_UART2_BASE,
        BRH_UART2_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_LED_VBASE,
        BRH_LED_BASE,
        BRH_LED_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_PCI_IO_VBASE,
        BECC_PCI_IO_BASE,
        BRH_PCI_IO_VSIZE
    ),
    DEVMAP_ENTRY(
        BRH_BECC_VBASE,
        BECC_REG_BASE,
        BRH_BECC_VSIZE
    ),
    DEVMAP_ENTRY_END
};

static void
brh_hardclock_hook(void)
{
        static int snakefreq;

        if ((snakefreq++ & 15) == 0)
                brh_7seg_snake();
}

/*
 * vaddr_t initarm(...)
 *
 * Initial entry point on startup. This gets called before main() is
 * entered.
 * It should be responsible for setting up everything that must be
 * in place when main is called.
 * This includes
 *   Taking a copy of the boot configuration structure.
 *   Initialising the physical console so characters can be printed.
 *   Setting up page tables for the kernel
 *   Relocating the kernel to the bottom of physical memory
 */
vaddr_t
initarm(void *arg)
{
        int loop;
        int loop1;
        u_int l1pagetable;
        paddr_t memstart;
        psize_t memsize;

        /*
         * Clear out the 7-segment display.  Whee, the first visual
         * indication that we're running kernel code.
         */
        brh_7seg(' ');

        /*
         * Since we have mapped the on-board devices at their permanent
         * locations already, it is possible for us to initialize
         * the console now.
         */
        consinit();

#ifdef VERBOSE_INIT_ARM
        /* Talk to the user */
        printf("\nNetBSD/evbarm (ADI BRH) booting ...\n");
#endif

        /* Calibrate the delay loop. */
        becc_hardclock_hook = brh_hardclock_hook;

        /*
         * Heads up ... Setup the CPU / MMU / TLB functions
         */
        if (set_cpufuncs())
                panic("CPU not recognized!");

        /*
         * We are currently running with the MMU enabled and the
         * entire address space mapped VA==PA.  Memory conveniently
         * starts at 0xc0000000, which is where we want it.  Certain
         * on-board devices have already been mapped where we want
         * them to be.  There is an L1 page table at 0xc0004000.
         */

        becc_icu_init();

        /*
         * Memory always starts at 0xc0000000 on a BRH, and the
         * memory size is always 128M.
         */
        memstart = 0xc0000000UL;
        memsize = (128UL * 1024 * 1024);

#ifdef VERBOSE_INIT_ARM
        printf("initarm: Configuring system ...\n");
#endif

        /* Fake bootconfig structure for the benefit of pmap.c */
        /* XXX must make the memory description h/w independent */
        bootconfig.dramblocks = 1;
        bootconfig.dram[0].address = memstart;
        bootconfig.dram[0].pages = memsize / PAGE_SIZE;

        /*
         * Set up the variables that define the availability of
         * physical memory.  For now, we're going to set
         * physical_freestart to 0xc0200000 (where the kernel
         * was loaded), and allocate the memory we need downwards.
         * If we get too close to the L1 table that we set up, we
         * will panic.  We will update physical_freestart and
         * physical_freeend later to reflect what pmap_bootstrap()
         * wants to see.
         *
         * XXX pmap_bootstrap() needs an enema.
         */
        physical_start = bootconfig.dram[0].address;
        physical_end = physical_start + (bootconfig.dram[0].pages * PAGE_SIZE);

        physical_freestart = 0xc0009000UL;
        physical_freeend = 0xc0200000UL;

#ifdef VERBOSE_INIT_ARM
        /* Tell the user about the memory */
        printf("physmemory: 0x%"PRIxPSIZE" pages at "
            "0x%08"PRIxPADDR" -> 0x%08"PRIxPADDR"\n",
            physmem, physical_start, physical_end - 1);
#endif

        /*
         * Okay, the kernel starts 2MB in from the bottom of physical
         * memory.  We are going to allocate our bootstrap pages downwards
         * from there.
         *
         * We need to allocate some fixed page tables to get the kernel
         * going.  We allocate one page directory and a number of page
         * tables and store the physical addresses in the kernel_pt_table
         * array.
         *
         * The kernel page directory must be on a 16K boundary.  The page
         * tables must be on 4K boundaries.  What we do is allocate the
         * page directory on the first 16K boundary that we encounter, and
         * the page tables on 4K boundaries otherwise.  Since we allocate
         * at least 3 L2 page tables, we are guaranteed to encounter at
         * least one 16K aligned region.
         */

#ifdef VERBOSE_INIT_ARM
        printf("Allocating page tables\n");
#endif

        free_pages = (physical_freeend - physical_freestart) / PAGE_SIZE;

#ifdef VERBOSE_INIT_ARM
        printf("freestart = 0x%08lx, free_pages = %d (0x%08x)\n",
               physical_freestart, free_pages, free_pages);
#endif

        /* Define a macro to simplify memory allocation */
#define valloc_pages(var, np)                           \
        alloc_pages((var).pv_pa, (np));                 \
        (var).pv_va = KERNEL_BASE + (var).pv_pa - physical_start;

#define alloc_pages(var, np)                            \
        physical_freeend -= ((np) * PAGE_SIZE);         \
        if (physical_freeend < physical_freestart)      \
                panic("initarm: out of memory");        \
        (var) = physical_freeend;                       \
        free_pages -= (np);                             \
        memset((char *)(var), 0, ((np) * PAGE_SIZE));

        loop1 = 0;
        for (loop = 0; loop <= NUM_KERNEL_PTS; ++loop) {
                /* Are we 16KB aligned for an L1 ? */
                if (((physical_freeend - L1_TABLE_SIZE) & (L1_TABLE_SIZE - 1)) == 0
                    && kernel_l1pt.pv_pa == 0) {
                        valloc_pages(kernel_l1pt, L1_TABLE_SIZE / PAGE_SIZE);
                } else {
                        valloc_pages(kernel_pt_table[loop1],
                            L2_TABLE_SIZE / PAGE_SIZE);
                        ++loop1;
                }
        }

        /* This should never be able to happen but better confirm that. */
        if (!kernel_l1pt.pv_pa || (kernel_l1pt.pv_pa & (L1_TABLE_SIZE-1)) != 0)
                panic("initarm: Failed to align the kernel page directory\n");

        /*
         * Allocate a page for the system page mapped to V0x00000000
         * This page will just contain the system vectors and can be
         * shared by all processes.
         */
        alloc_pages(systempage.pv_pa, 1);

        /* Allocate stacks for all modes */
        valloc_pages(irqstack, IRQ_STACK_SIZE);
        valloc_pages(abtstack, ABT_STACK_SIZE);
        valloc_pages(undstack, UND_STACK_SIZE);
        valloc_pages(kernelstack, UPAGES);

        /* Allocate enough pages for cleaning the Mini-Data cache. */
        KASSERT(xscale_minidata_clean_size <= PAGE_SIZE);
        valloc_pages(minidataclean, 1);

#ifdef VERBOSE_INIT_ARM
        printf("IRQ stack: p0x%08lx v0x%08lx\n", irqstack.pv_pa,
            irqstack.pv_va);
        printf("ABT stack: p0x%08lx v0x%08lx\n", abtstack.pv_pa,
            abtstack.pv_va);
        printf("UND stack: p0x%08lx v0x%08lx\n", undstack.pv_pa,
            undstack.pv_va);
        printf("SVC stack: p0x%08lx v0x%08lx\n", kernelstack.pv_pa,
            kernelstack.pv_va);
#endif

        /*
         * XXX Defer this to later so that we can reclaim the memory
         * XXX used by the RedBoot page tables.
         */
        alloc_pages(msgbufphys, round_page(MSGBUFSIZE) / PAGE_SIZE);

        /*
         * Ok we have allocated physical pages for the primary kernel
         * page tables
         */

#ifdef VERBOSE_INIT_ARM
        printf("Creating L1 page table at 0x%08lx\n", kernel_l1pt.pv_pa);
#endif

        /*
         * Now we start construction of the L1 page table
         * We start by mapping the L2 page tables into the L1.
         * This means that we can replace L1 mappings later on if necessary
         */
        l1pagetable = kernel_l1pt.pv_pa;

        /* Map the L2 pages tables in the L1 page table */
        pmap_link_l2pt(l1pagetable, ARM_VECTORS_HIGH & ~(0x00400000 - 1),
            &kernel_pt_table[KERNEL_PT_SYS]);
        for (loop = 0; loop < KERNEL_PT_KERNEL_NUM; loop++)
                pmap_link_l2pt(l1pagetable, KERNEL_BASE + loop * 0x00400000,
                    &kernel_pt_table[KERNEL_PT_KERNEL + loop]);
        for (loop = 0; loop < KERNEL_PT_VMDATA_NUM; loop++)
                pmap_link_l2pt(l1pagetable, KERNEL_VM_BASE + loop * 0x00400000,
                    &kernel_pt_table[KERNEL_PT_VMDATA + loop]);

        /* update the top of the kernel VM */
        pmap_curmaxkvaddr =
            KERNEL_VM_BASE + (KERNEL_PT_VMDATA_NUM * 0x00400000);

#ifdef VERBOSE_INIT_ARM
        printf("Mapping kernel\n");
#endif

        /* Now we fill in the L2 pagetable for the kernel static code/data */
        {
                extern char etext[], _end[];
                size_t textsize = (uintptr_t) etext - KERNEL_TEXT_BASE;
                size_t totalsize = (uintptr_t) _end - KERNEL_TEXT_BASE;
                u_int logical;

                textsize = (textsize + PGOFSET) & ~PGOFSET;
                totalsize = (totalsize + PGOFSET) & ~PGOFSET;

                logical = 0x00200000;   /* offset of kernel in RAM */

                logical += pmap_map_chunk(l1pagetable, KERNEL_BASE + logical,
                    physical_start + logical, textsize,
                    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
                logical += pmap_map_chunk(l1pagetable, KERNEL_BASE + logical,
                    physical_start + logical, totalsize - textsize,
                    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
        }

#ifdef VERBOSE_INIT_ARM
        printf("Constructing L2 page tables\n");
#endif

        /* Map the stack pages */
        pmap_map_chunk(l1pagetable, irqstack.pv_va, irqstack.pv_pa,
            IRQ_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
        pmap_map_chunk(l1pagetable, abtstack.pv_va, abtstack.pv_pa,
            ABT_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
        pmap_map_chunk(l1pagetable, undstack.pv_va, undstack.pv_pa,
            UND_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
        pmap_map_chunk(l1pagetable, kernelstack.pv_va, kernelstack.pv_pa,
            UPAGES * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);

        pmap_map_chunk(l1pagetable, kernel_l1pt.pv_va, kernel_l1pt.pv_pa,
            L1_TABLE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_PAGETABLE);

        for (loop = 0; loop < NUM_KERNEL_PTS; ++loop) {
                pmap_map_chunk(l1pagetable, kernel_pt_table[loop].pv_va,
                    kernel_pt_table[loop].pv_pa, L2_TABLE_SIZE,
                    VM_PROT_READ|VM_PROT_WRITE, PTE_PAGETABLE);
        }

        /* Map the Mini-Data cache clean area. */
        xscale_setup_minidata(l1pagetable, minidataclean.pv_va,
            minidataclean.pv_pa);

        /* Map the vector page. */
        pmap_map_entry(l1pagetable, ARM_VECTORS_HIGH, systempage.pv_pa,
            VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);

        /* Map the statically mapped devices. */
        pmap_devmap_bootstrap(l1pagetable, brh_devmap);

        /*
         * Give the XScale global cache clean code an appropriately
         * sized chunk of unmapped VA space starting at 0xff500000
         * (our device mappings end before this address).
         */
        xscale_cache_clean_addr = 0xff500000U;

        /*
         * Now we have the real page tables in place so we can switch to them.
         * Once this is done we will be running with the REAL kernel page
         * tables.
         */

        /* Switch tables */
#ifdef VERBOSE_INIT_ARM
        printf("switching to new L1 page table  @%#lx...", kernel_l1pt.pv_pa);
#endif
        cpu_domains((DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL*2)) | DOMAIN_CLIENT);
        cpu_setttb(kernel_l1pt.pv_pa, true);
        cpu_tlb_flushID();
        cpu_domains(DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL*2));

        /*
         * Move from cpu_startup() as data_abort_handler() references
         * this during uvm init
         */
        uvm_lwp_setuarea(&lwp0, kernelstack.pv_va);

#ifdef VERBOSE_INIT_ARM
        printf("done!\n");
#endif

#ifdef VERBOSE_INIT_ARM
        printf("bootstrap done.\n");
#endif

        /*
         * Inform the BECC code where the BECC is mapped.
         */
        becc_vaddr = BRH_BECC_VBASE;

        /*
         * Now that we have becc_vaddr set, calibrate delay.
         */
        becc_calibrate_delay();

        /*
         * BECC <= Rev7 can only address 64M through the inbound
         * PCI windows.  Limit memory to 64M on those revs.  (This
         * problem was fixed in Rev8 of the BECC; get an FPGA upgrade.)
         */
        {
                vaddr_t va = BRH_PCI_CONF_VBASE | (1U << BECC_IDSEL_BIT) |
                    PCI_CLASS_REG;
                uint32_t reg;

                reg = *(volatile uint32_t *) va;
                becc_rev = PCI_REVISION(reg);
                if (becc_rev <= BECC_REV_V7 &&
                    memsize > (64UL * 1024 * 1024)) {
                        memsize = (64UL * 1024 * 1024);
                        bootconfig.dram[0].pages = memsize / PAGE_SIZE;
                        physical_end = physical_start +
                            (bootconfig.dram[0].pages * PAGE_SIZE);
                        printf("BECC <= Rev7: memory truncated to 64M\n");
                }
        }

        /*
         * Update the physical_freestart/physical_freeend/free_pages
         * variables.
         */
        {
                extern char _end[];

                physical_freestart = physical_start +
                    (((((uintptr_t) _end) + PGOFSET) & ~PGOFSET) -
                     KERNEL_BASE);
                physical_freeend = physical_end;
                free_pages =
                    (physical_freeend - physical_freestart) / PAGE_SIZE;
        }
#ifdef VERBOSE_INIT_ARM
        printf("freestart = 0x%08lx, free_pages = %d (0x%x)\n",
               physical_freestart, free_pages, free_pages);
#endif

        physmem = (physical_end - physical_start) / PAGE_SIZE;

        arm32_vector_init(ARM_VECTORS_HIGH, ARM_VEC_ALL);

        /*
         * Pages were allocated during the secondary bootstrap for the
         * stacks for different CPU modes.
         * We must now set the r13 registers in the different CPU modes to
         * point to these stacks.
         * Since the ARM stacks use STMFD etc. we must set r13 to the top end
         * of the stack memory.
         */
#ifdef VERBOSE_INIT_ARM
        printf("init subsystems: stacks ");
#endif

        set_stackptr(PSR_IRQ32_MODE,
            irqstack.pv_va + IRQ_STACK_SIZE * PAGE_SIZE);
        set_stackptr(PSR_ABT32_MODE,
            abtstack.pv_va + ABT_STACK_SIZE * PAGE_SIZE);
        set_stackptr(PSR_UND32_MODE,
            undstack.pv_va + UND_STACK_SIZE * PAGE_SIZE);

        /*
         * Well we should set a data abort handler.
         * Once things get going this will change as we will need a proper
         * handler.
         * Until then we will use a handler that just panics but tells us
         * why.
         * Initialisation of the vectors will just panic on a data abort.
         * This just fills in a slightly better one.
         */
#ifdef VERBOSE_INIT_ARM
        printf("vectors ");
#endif
        data_abort_handler_address = (u_int)data_abort_handler;
        prefetch_abort_handler_address = (u_int)prefetch_abort_handler;
        undefined_handler_address = (u_int)undefinedinstruction_bounce;

        /* Initialise the undefined instruction handlers */
#ifdef VERBOSE_INIT_ARM
        printf("undefined ");
#endif
        undefined_init();

        /* Load memory into UVM. */
#ifdef VERBOSE_INIT_ARM
        printf("page ");
#endif
        uvm_md_init();
        uvm_page_physload(atop(physical_freestart), atop(physical_freeend),
            atop(physical_freestart), atop(physical_freeend),
            VM_FREELIST_DEFAULT);

        /* Boot strap pmap telling it where the managed kernel virtual memory is */
#ifdef VERBOSE_INIT_ARM
        printf("pmap ");
#endif
        pmap_bootstrap(KERNEL_VM_BASE, KERNEL_VM_BASE + KERNEL_VM_SIZE);

        /* Setup the IRQ system */
#ifdef VERBOSE_INIT_ARM
        printf("irq ");
#endif
        becc_intr_init();
#ifdef VERBOSE_INIT_ARM
        printf("done.\n");
#endif

#ifdef DDB
        db_machine_init();
        if (boothowto & RB_KDB)
                Debugger();
#endif

        /* We return the new stack pointer address */
        return(kernelstack.pv_va + USPACE_SVC_STACK_TOP);
}

void
consinit(void)
{
        static const bus_addr_t comcnaddrs[] = {
                BRH_UART1_BASE,         /* com0 */
                BRH_UART2_BASE,         /* com1 */
        };
        static int consinit_called;

        if (consinit_called != 0)
                return;

        consinit_called = 1;

        /*
         * brh_start() has mapped the console devices for us per
         * the devmap, so register it now so drivers can map the
         * console device.
         */
        pmap_devmap_register(brh_devmap);

#if NCOM > 0
        if (comcnattach(&obio_bs_tag, comcnaddrs[comcnunit], comcnspeed,
            BECC_PERIPH_CLOCK, COM_TYPE_NORMAL, comcnmode))
                panic("can't init serial console @%lx", comcnaddrs[comcnunit]);
#else
        panic("serial console @%lx not configured", comcnaddrs[comcnunit]);
#endif
}