Home | History | Annotate | Line # | Download | only in acorn32
      1 /*	$NetBSD: rpc_machdep.c,v 1.101 2022/05/15 20:37:50 andvar Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2000-2002 Reinoud Zandijk.
      5  * Copyright (c) 1994-1998 Mark Brinicombe.
      6  * Copyright (c) 1994 Brini.
      7  * All rights reserved.
      8  *
      9  * This code is derived from software written for Brini by Mark Brinicombe
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by Brini.
     22  * 4. The name of the company nor the name of the author may be used to
     23  *    endorse or promote products derived from this software without specific
     24  *    prior written permission.
     25  *
     26  * THIS SOFTWARE IS PROVIDED BY BRINI ``AS IS'' AND ANY EXPRESS OR IMPLIED
     27  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     28  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     29  * IN NO EVENT SHALL BRINI OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
     30  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     31  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     32  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     36  * SUCH DAMAGE.
     37  *
     38  * RiscBSD kernel project
     39  *
     40  * machdep.c
     41  *
     42  * Machine dependent functions for kernel setup
     43  *
     44  * This file still needs a lot of work
     45  *
     46  * Created      : 17/09/94
     47  * Updated for yet another new bootloader 28/12/02
     48  */
     49 
     50 #include "opt_ddb.h"
     51 #include "opt_modular.h"
     52 #include "vidcvideo.h"
     53 #include "podulebus.h"
     54 
     55 #include <sys/param.h>
     56 
     57 __KERNEL_RCSID(0, "$NetBSD: rpc_machdep.c,v 1.101 2022/05/15 20:37:50 andvar Exp $");
     58 
     59 #include <sys/systm.h>
     60 #include <sys/kernel.h>
     61 #include <sys/reboot.h>
     62 #include <sys/proc.h>
     63 #include <sys/msgbuf.h>
     64 #include <sys/exec.h>
     65 #include <sys/exec_aout.h>
     66 #include <sys/ksyms.h>
     67 #include <sys/bus.h>
     68 #include <sys/cpu.h>
     69 #include <sys/intr.h>
     70 #include <sys/device.h>
     71 
     72 #include <dev/cons.h>
     73 
     74 #include <dev/ic/pckbcvar.h>
     75 
     76 #include <dev/i2c/i2cvar.h>
     77 #include <dev/i2c/pcf8583var.h>
     78 
     79 #include <machine/db_machdep.h>
     80 #include <ddb/db_sym.h>
     81 #include <ddb/db_extern.h>
     82 
     83 #include <uvm/uvm.h>
     84 
     85 #include <arm/locore.h>
     86 #include <arm/undefined.h>
     87 #include <arm/arm32/machdep.h>
     88 #include <arm/arm32/pmap.h>
     89 
     90 #include <machine/rtc.h>
     91 #include <machine/signal.h>
     92 #include <machine/bootconfig.h>
     93 #include <machine/io.h>
     94 
     95 #include <arm/iomd/vidc.h>
     96 #include <arm/iomd/iomdreg.h>
     97 #include <arm/iomd/iomdvar.h>
     98 #include <arm/iomd/vidcvideo.h>
     99 #include <arm/iomd/iomdiicvar.h>
    100 
    101 static i2c_tag_t acorn32_i2c_tag;
    102 
    103 #include "ksyms.h"
    104 
    105 /* Kernel text starts at the base of the kernel address space. */
    106 #define	KERNEL_TEXT_BASE	(KERNEL_BASE + 0x00000000)
    107 #define	KERNEL_VM_BASE		(KERNEL_BASE + 0x01000000)
    108 
    109 /*
    110  * The range 0xf1000000 - 0xf5ffffff is available for kernel VM space
    111  * Fixed mappings exist from 0xf6000000 - 0xffffffff
    112  */
    113 #define	KERNEL_VM_SIZE		0x05000000
    114 
    115 struct bootconfig bootconfig;	/* Boot config storage */
    116 videomemory_t videomemory;	/* Video memory descriptor */
    117 
    118 char *boot_args = NULL;		/* holds the pre-processed boot arguments */
    119 extern char *booted_kernel;	/* used for ioctl to retrieve booted kernel */
    120 
    121 extern int       *vidc_base;
    122 extern uint32_t  iomd_base;
    123 extern struct bus_space iomd_bs_tag;
    124 
    125 paddr_t physical_start;
    126 paddr_t kernel_start;
    127 paddr_t physical_freestart;
    128 paddr_t physical_freeend;
    129 paddr_t physical_end;
    130 paddr_t dma_range_begin;
    131 paddr_t dma_range_end;
    132 
    133 u_int free_pages;
    134 paddr_t memoryblock_end;
    135 
    136 #ifndef PMAP_STATIC_L1S
    137 int max_processes = 64;		/* Default number */
    138 #endif	/* !PMAP_STATIC_L1S */
    139 
    140 u_int videodram_size = 0;	/* Amount of DRAM to reserve for video */
    141 
    142 paddr_t msgbufphys;
    143 
    144 #define	KERNEL_PT_VMEM		0 /* Page table for mapping video memory */
    145 #define	KERNEL_PT_SYS		1 /* Page table for mapping proc0 zero page */
    146 #define	KERNEL_PT_KERNEL	2 /* Page table for mapping kernel 0-4MB*/
    147 #define	KERNEL_PT_KERNEL_4MB	3 /* Page table for mapping kernel 4-8MB*/
    148 #define	KERNEL_PT_VMDATA	4 /* Page tables for mapping kernel VM */
    149 #define	KERNEL_PT_VMDATA_NUM	4 /* start with 16MB of KVM */
    150 #define	NUM_KERNEL_PTS		(KERNEL_PT_VMDATA + KERNEL_PT_VMDATA_NUM)
    151 
    152 pv_addr_t kernel_pt_table[NUM_KERNEL_PTS];
    153 
    154 #ifdef CPU_SA110
    155 #define CPU_SA110_CACHE_CLEAN_SIZE (0x4000 * 2)
    156 static vaddr_t sa110_cc_base;
    157 #endif	/* CPU_SA110 */
    158 
    159 /* Prototypes */
    160 void physcon_display_base(u_int);
    161 extern void consinit(void);
    162 
    163 void data_abort_handler(trapframe_t *);
    164 void prefetch_abort_handler(trapframe_t *);
    165 void undefinedinstruction_bounce(trapframe_t *frame);
    166 
    167 static void canonicalise_bootconfig(struct bootconfig *, struct bootconfig *);
    168 static void process_kernel_args(void);
    169 
    170 extern void dump_spl_masks(void);
    171 
    172 void rpc_sa110_cc_setup(void);
    173 
    174 void parse_rpc_bootargs(char *args);
    175 
    176 extern void dumpsys(void);
    177 
    178 
    179 #	define console_flush()		/* empty */
    180 
    181 
    182 #define panic2(a) do {							\
    183 	memset((void *) (videomemory.vidm_vbase), 0x55, 50*1024);	\
    184 	consinit();							\
    185 	panic a;							\
    186 } while (/* CONSTCOND */ 0)
    187 
    188 /*
    189  * void cpu_reboot(int howto, char *bootstr)
    190  *
    191  * Reboots the system
    192  *
    193  * Deal with any syncing, unmounting, dumping and shutdown hooks,
    194  * then reset the CPU.
    195  */
    196 
    197 /* NOTE: These variables will be removed, well some of them */
    198 
    199 extern u_int current_mask;
    200 
    201 void
    202 cpu_reboot(int howto, char *bootstr)
    203 {
    204 
    205 #ifdef DIAGNOSTIC
    206 	printf("boot: howto=%08x curlwp=%p\n", howto, curlwp);
    207 
    208 	printf("ipl_bio=%08x ipl_net=%08x ipl_tty=%08x ipl_vm=%08x\n",
    209 	    irqmasks[IPL_BIO], irqmasks[IPL_NET], irqmasks[IPL_TTY],
    210 	    irqmasks[IPL_VM]);
    211 	printf("ipl_audio=%08x ipl_clock=%08x ipl_none=%08x\n",
    212 	    irqmasks[IPL_AUDIO], irqmasks[IPL_CLOCK], irqmasks[IPL_NONE]);
    213 
    214 	dump_spl_masks();
    215 #endif	/* DIAGNOSTIC */
    216 
    217 	/*
    218 	 * If we are still cold then hit the air brakes
    219 	 * and crash to earth fast
    220 	 */
    221 	if (cold) {
    222 		doshutdownhooks();
    223 		pmf_system_shutdown(boothowto);
    224 		printf("Halted while still in the ICE age.\n");
    225 		printf("The operating system has halted.\n");
    226 		printf("Please press any key to reboot.\n\n");
    227 		cngetc();
    228 		printf("rebooting...\n");
    229 		cpu_reset();
    230 		/*NOTREACHED*/
    231 	}
    232 
    233 	/* Disable console buffering */
    234 	cnpollc(1);
    235 
    236 	/*
    237 	 * If RB_NOSYNC was not specified sync the discs.
    238 	 * Note: Unless cold is set to 1 here, syslogd will die during
    239 	 * the unmount.  It looks like syslogd is getting woken up
    240 	 * only to find that it cannot page part of the binary in as
    241 	 * the filesystem has been unmounted.
    242 	 */
    243 	if (!(howto & RB_NOSYNC))
    244 		bootsync();
    245 
    246 	/* Say NO to interrupts */
    247 	splhigh();
    248 
    249 	/* Do a dump if requested. */
    250 	if ((howto & (RB_DUMP | RB_HALT)) == RB_DUMP)
    251 		dumpsys();
    252 
    253 	/*
    254 	 * Auto reboot overload protection
    255 	 *
    256 	 * This code stops the kernel entering an endless loop of reboot
    257 	 * - panic cycles. This will have the effect of stopping further
    258 	 * reboots after it has rebooted 8 times after panics. A clean
    259 	 * halt or reboot will reset the counter.
    260 	 */
    261 
    262 	/*
    263 	 * Have we done 8 reboots in a row ? If so halt rather than reboot
    264 	 * since 8 panics in a row without 1 clean halt means something is
    265 	 * seriously wrong.
    266 	 */
    267 	if (cmos_read(RTC_ADDR_REBOOTCNT) > 8)
    268 		howto |= RB_HALT;
    269 
    270 	/*
    271 	 * If we are rebooting on a panic then up the reboot count
    272 	 * otherwise reset.
    273 	 * This will thus be reset if the kernel changes the boot action from
    274 	 * reboot to halt due to too any reboots.
    275 	 */
    276 	if (((howto & RB_HALT) == 0) && panicstr)
    277 		cmos_write(RTC_ADDR_REBOOTCNT,
    278 		   cmos_read(RTC_ADDR_REBOOTCNT) + 1);
    279 	else
    280 		cmos_write(RTC_ADDR_REBOOTCNT, 0);
    281 
    282 	/*
    283 	 * If we need a RiscBSD reboot, request it buy setting a bit in
    284 	 * the CMOS RAM. This can be detected by the RiscBSD boot loader
    285 	 * during a RISCOS boot. No other way to do this as RISCOS is in ROM.
    286 	 */
    287 	if ((howto & RB_HALT) == 0)
    288 		cmos_write(RTC_ADDR_BOOTOPTS,
    289 		    cmos_read(RTC_ADDR_BOOTOPTS) | 0x02);
    290 
    291 	/* Run any shutdown hooks */
    292 	doshutdownhooks();
    293 
    294 	pmf_system_shutdown(boothowto);
    295 
    296 	/* Make sure IRQ's are disabled */
    297 	IRQdisable;
    298 
    299 	if (howto & RB_HALT) {
    300 		printf("The operating system has halted.\n");
    301 		printf("Please press any key to reboot.\n\n");
    302 		cngetc();
    303 	}
    304 
    305 	printf("rebooting...\n");
    306 	cpu_reset();
    307 	/*NOTREACHED*/
    308 }
    309 
    310 
    311 /*
    312  * u_int initarm(BootConfig *bootconf)
    313  *
    314  * Initial entry point on startup. This gets called before main() is
    315  * entered.
    316  * It should be responsible for setting up everything that must be
    317  * in place when main is called.
    318  * This includes
    319  *   Taking a copy of the boot configuration structure.
    320  *   Initialising the physical console so characters can be printed.
    321  *   Setting up page tables for the kernel
    322  *   Relocating the kernel to the bottom of physical memory
    323  */
    324 
    325 /*
    326  * this part is completely rewritten for the new bootloader ... It features
    327  * a flat memory map with a mapping comparable to the EBSA arm32 machine
    328  * to boost the portability and likeness of the code
    329  */
    330 
    331 /*
    332  * Mapping table for core kernel memory. This memory is mapped at init
    333  * time with section mappings.
    334  *
    335  * XXX One big assumption in the current architecture seems that the kernel is
    336  * XXX supposed to be mapped into bootconfig.dram[0].
    337  */
    338 
    339 #define ONE_MB	0x100000
    340 
    341 struct l1_sec_map {
    342 	vaddr_t		va;
    343 	paddr_t		pa;
    344 	vsize_t		size;
    345 	vm_prot_t	prot;
    346 	int		cache;
    347 } l1_sec_table[] = {
    348 	/* Map 1Mb section for VIDC20 */
    349 	{ VIDC_BASE,		VIDC_HW_BASE,
    350 	    ONE_MB,		VM_PROT_READ|VM_PROT_WRITE,
    351 	    PTE_NOCACHE },
    352 
    353 	/* Map 1Mb section from IOMD */
    354 	{ IOMD_BASE,		IOMD_HW_BASE,
    355 	    ONE_MB,		VM_PROT_READ|VM_PROT_WRITE,
    356 	    PTE_NOCACHE },
    357 
    358 	/* Map 1Mb of COMBO (and module space) */
    359 	{ IO_BASE,		IO_HW_BASE,
    360 	    ONE_MB,		VM_PROT_READ|VM_PROT_WRITE,
    361 	    PTE_NOCACHE },
    362 #if NPODULEBUS > 0	/* XXXJRT */
    363 	/* Map the Fast and Sync simple podule space */
    364 	{ SYNC_PODULE_BASE & 0xfff00000, SYNC_PODULE_HW_BASE & 0xfff00000,
    365 	    L1_S_SIZE,		VM_PROT_READ|VM_PROT_WRITE,
    366 	    PTE_NOCACHE },
    367 	/* Map the EASI podule space */
    368 	{ EASI_BASE,		EASI_HW_BASE,
    369 	    MAX_PODULES * EASI_SIZE,	VM_PROT_READ|VM_PROT_WRITE,
    370 	    PTE_NOCACHE },
    371 #endif
    372 	{ 0, 0, 0, 0, 0 }
    373 };
    374 
    375 
    376 static void
    377 canonicalise_bootconfig(struct bootconfig *bootconf, struct bootconfig *raw_bootconf)
    378 {
    379 	/* check for bootconfig v2+ structure */
    380 	if (raw_bootconf->magic == BOOTCONFIG_MAGIC) {
    381 		/* v2+ cleaned up structure found */
    382 		*bootconf = *raw_bootconf;
    383 		return;
    384 	} else {
    385 		panic2(("Internal error: no valid bootconfig block found"));
    386 	}
    387 }
    388 
    389 
    390 vaddr_t
    391 initarm(void *cookie)
    392 {
    393 	struct bootconfig *raw_bootconf = cookie;
    394 	int loop;
    395 	int loop1;
    396 	u_int logical;
    397 	u_int kerneldatasize;
    398 	u_int l1pagetable;
    399 	struct exec *kernexec = (struct exec *)KERNEL_TEXT_BASE;
    400 	bool hasKinetic = false;
    401 	paddr_t kinetic_physical_start;
    402 
    403 	/*
    404 	 * Heads up ... Setup the CPU / MMU / TLB functions
    405 	 */
    406 	set_cpufuncs();
    407 
    408 	/* canonicalise the boot configuration structure to allow versioning */
    409 	canonicalise_bootconfig(&bootconfig, raw_bootconf);
    410 	booted_kernel = bootconfig.kernelname;
    411 
    412 	/* if the wscons interface is used, switch off VERBOSE booting :( */
    413 #if NVIDCVIDEO>0
    414 #	undef VERBOSE_INIT_ARM
    415 #endif
    416 
    417 	/*
    418 	 * Initialise the video memory descriptor
    419 	 *
    420 	 * Note: all references to the video memory virtual/physical address
    421 	 * should go via this structure.
    422 	 */
    423 
    424 	/* Hardwire it on the place the bootloader tells us */
    425 	videomemory.vidm_vbase = bootconfig.display_start;
    426 	videomemory.vidm_pbase = bootconfig.display_phys;
    427 	videomemory.vidm_size = bootconfig.display_size;
    428 	if (bootconfig.vram[0].pages)
    429 		videomemory.vidm_type = VIDEOMEM_TYPE_VRAM;
    430 	else
    431 		videomemory.vidm_type = VIDEOMEM_TYPE_DRAM;
    432 	vidc_base = (int *) VIDC_HW_BASE;
    433 	iomd_base =         IOMD_HW_BASE;
    434 
    435 	/*
    436 	 * Initialise the physical console
    437 	 * This is done in main() but for the moment we do it here so that
    438 	 * we can use printf in initarm() before main() has been called.
    439 	 * only for `vidcconsole!' ... not wscons
    440 	 */
    441 #if NVIDCVIDEO == 0
    442 	consinit();
    443 #endif
    444 
    445 	/*
    446 	 * Initialise the diagnostic serial console
    447 	 * This allows a means of generating output during initarm().
    448 	 * Once all the memory map changes are complete we can call consinit()
    449 	 * and not have to worry about things moving.
    450 	 */
    451 	/* fcomcnattach(DC21285_ARMCSR_BASE, comcnspeed, comcnmode); */
    452 	/* XXX snif .... i am still not able to this */
    453 
    454 	/*
    455 	 * We have the following memory map (derived from EBSA)
    456 	 *
    457 	 * virtual address == physical address apart from the areas:
    458 	 * 0x00000000 -> 0x000fffff which is mapped to
    459 	 * top 1MB of physical memory
    460 	 * 0xf0000000 -> 0xf0ffffff which is mapped to
    461 	 * physical address 0x10000000 -> 0x10ffffff
    462 	 * or on a Kinetic:
    463 	 * physical address 0x20400000 -> 0x20ffffff
    464 	 *
    465 	 * This means that the kernel is mapped suitably for continuing
    466 	 * execution, all I/O is mapped 1:1 virtual to physical and
    467 	 * physical memory is accessible.
    468 	 *
    469 	 * The initarm() has the responsibility for creating the kernel
    470 	 * page tables.
    471 	 * It must also set up various memory pointers that are used
    472 	 * by pmap etc.
    473 	 */
    474 
    475 #ifdef FORCE_VERBOSE_INIT_ARM
    476 	/*
    477 	 * note that this will stop working after we switch to the new
    478 	 * L1 Table
    479 	 */
    480 	memset((void *) (videomemory.vidm_vbase), 0x55, videomemory.vidm_size);
    481 	consinit();
    482 	printf("\n\n\n\n\n\n\n");
    483 #define VERBOSE_INIT_ARM
    484 #endif
    485 	/* START OF REAL NEW STUFF */
    486 
    487 	/* Check to make sure the page size is correct */
    488 	if (PAGE_SIZE != bootconfig.pagesize)
    489 		panic2(("Page size is %d bytes instead of %d !! (huh?)\n",
    490 			   bootconfig.pagesize, PAGE_SIZE));
    491 
    492 	/* process arguments */
    493 	process_kernel_args();
    494 
    495 	/*
    496 	 * Now set up the page tables for the kernel ... this part is copied
    497 	 * in a (modified?) way from the EBSA machine port....
    498 	 */
    499 
    500 #ifdef VERBOSE_INIT_ARM
    501 	printf("Allocating page tables\n");
    502 #endif
    503 	/*
    504 	 * Set up the variables that define the availability of physical
    505 	 * memory
    506 	 */
    507 	physical_start = 0xffffffff;
    508 	physical_end = 0;
    509 	kinetic_physical_start = 0xffffffff;
    510 #ifdef VERBOSE_INIT_ARM
    511 	printf("memory blocks:\n");
    512 #endif
    513 	for (loop = 0, physmem = 0; loop < bootconfig.dramblocks; ++loop) {
    514 #ifdef VERBOSE_INIT_ARM
    515 		printf("0x%x + 0x%0x, type = 0x%08x\n", bootconfig.dram[loop].address,
    516 				 bootconfig.dram[loop].pages * PAGE_SIZE,
    517 				 bootconfig.dram[loop].flags);
    518 #endif
    519 	    	if (bootconfig.dram[loop].address < physical_start)
    520 			physical_start = bootconfig.dram[loop].address;
    521 		memoryblock_end = bootconfig.dram[loop].address +
    522 		    bootconfig.dram[loop].pages * PAGE_SIZE;
    523 		if (memoryblock_end > physical_end)
    524 			physical_end = memoryblock_end;
    525 		physmem += bootconfig.dram[loop].pages;
    526 		if (bootconfig.dram[loop].flags & PHYSMEM_TYPE_PROCESSOR_ONLY) {
    527 			hasKinetic = true;
    528 			if (bootconfig.dram[loop].address < kinetic_physical_start)
    529 				kinetic_physical_start = bootconfig.dram[loop].address;
    530 		}
    531 	};
    532 
    533 	if (hasKinetic)
    534 	{
    535 		/* Kinetics can only DMA from the Normal DRAM */
    536 		dma_range_begin = 0xffffffff;
    537 		dma_range_end = 0;
    538 		for (loop = 0; loop < bootconfig.dramblocks; ++loop) {
    539 			if (bootconfig.dram[loop].flags == PHYSMEM_TYPE_GENERIC) {
    540 				if (bootconfig.dram[loop].address < dma_range_begin)
    541 					dma_range_begin = bootconfig.dram[loop].address;
    542 				memoryblock_end = bootconfig.dram[loop].address +
    543 					bootconfig.dram[loop].pages * PAGE_SIZE;
    544 				if (memoryblock_end > dma_range_end)
    545 					dma_range_end = memoryblock_end;
    546 			}
    547 		}
    548 		dma_range_end   = (paddr_t) MIN(dma_range_end, 256*1024*1024);
    549 	} else {
    550 		/* everything else DMAs all the memory */
    551 		dma_range_begin = (paddr_t) physical_start;
    552 		dma_range_end   = (paddr_t) MIN(physical_end, 512*1024*1024);
    553 	}
    554 
    555 	/* set the location of the kernel in physical memory */
    556 	if (hasKinetic) {
    557 		kernel_start = kinetic_physical_start;
    558 	} else {
    559 		kernel_start = physical_start;
    560 	}
    561 	physical_freestart = kernel_start;
    562 	free_pages = bootconfig.drampages;
    563 	physical_freeend = physical_end;
    564 
    565 	/*
    566 	 * AHUM !! set this variable ... it was set up in the old 1st
    567 	 * stage bootloader
    568 	 */
    569 	kerneldatasize = bootconfig.kernsize + bootconfig.MDFsize;
    570 
    571 	/* Update the address of the first free page of physical memory */
    572 	physical_freestart +=
    573 	    bootconfig.kernsize + bootconfig.scratchsize;
    574 	free_pages -= (bootconfig.kernsize + bootconfig.scratchsize) / PAGE_SIZE;
    575 
    576 	/* Define a macro to simplify memory allocation */
    577 #define	valloc_pages(var, np)						\
    578 	alloc_pages((var).pv_pa, (np));					\
    579 	(var).pv_va = KERNEL_BASE + (var).pv_pa - kernel_start;
    580 
    581 #define alloc_pages(var, np)						\
    582 	(var) = physical_freestart;					\
    583 	physical_freestart += ((np) * PAGE_SIZE);			\
    584 	free_pages -= (np);						\
    585 	memset((char *)(var), 0, ((np) * PAGE_SIZE));
    586 
    587 	loop1 = 0;
    588 	for (loop = 0; loop <= NUM_KERNEL_PTS; ++loop) {
    589 		/* Are we 16KB aligned for an L1 ? */
    590 		if ((physical_freestart & (L1_TABLE_SIZE - 1)) == 0
    591 		    && kernel_l1pt.pv_pa == 0) {
    592 			valloc_pages(kernel_l1pt, L1_TABLE_SIZE / PAGE_SIZE);
    593 		} else {
    594 			valloc_pages(kernel_pt_table[loop1],
    595 					L2_TABLE_SIZE / PAGE_SIZE);
    596 			++loop1;
    597 		}
    598 	}
    599 
    600 
    601 #ifdef DIAGNOSTIC
    602 	/* This should never be able to happen but better confirm that. */
    603 	if (!kernel_l1pt.pv_pa || (kernel_l1pt.pv_pa & (L1_TABLE_SIZE-1)) != 0)
    604 		panic2(("initarm: Failed to align the kernel page "
    605 		    "directory\n"));
    606 #endif
    607 
    608 	/*
    609 	 * Allocate a page for the system page mapped to V0x00000000
    610 	 * This page will just contain the system vectors and can be
    611 	 * shared by all processes.
    612 	 */
    613 	alloc_pages(systempage.pv_pa, 1);
    614 
    615 	/* Allocate stacks for all modes */
    616 	valloc_pages(irqstack, IRQ_STACK_SIZE);
    617 	valloc_pages(abtstack, ABT_STACK_SIZE);
    618 	valloc_pages(undstack, UND_STACK_SIZE);
    619 	valloc_pages(kernelstack, UPAGES);
    620 
    621 #ifdef VERBOSE_INIT_ARM
    622 	printf("Setting up stacks :\n");
    623 	printf("IRQ stack: p0x%08lx v0x%08lx\n",
    624 	    irqstack.pv_pa, irqstack.pv_va);
    625 	printf("ABT stack: p0x%08lx v0x%08lx\n",
    626 	    abtstack.pv_pa, abtstack.pv_va);
    627 	printf("UND stack: p0x%08lx v0x%08lx\n",
    628 	    undstack.pv_pa, undstack.pv_va);
    629 	printf("SVC stack: p0x%08lx v0x%08lx\n",
    630 	    kernelstack.pv_pa, kernelstack.pv_va);
    631 	printf("\n");
    632 #endif
    633 
    634 	alloc_pages(msgbufphys, round_page(MSGBUFSIZE) / PAGE_SIZE);
    635 
    636 #ifdef CPU_SA110
    637 	/*
    638 	 * XXX totally stuffed hack to work round problems introduced
    639 	 * in recent versions of the pmap code. Due to the calls used there
    640 	 * we cannot allocate virtual memory during bootstrap.
    641 	 */
    642 	sa110_cc_base = (KERNEL_BASE + (physical_freestart - kernel_start)
    643 	    + (CPU_SA110_CACHE_CLEAN_SIZE - 1))
    644 	    & ~(CPU_SA110_CACHE_CLEAN_SIZE - 1);
    645 #endif	/* CPU_SA110 */
    646 
    647 	/*
    648 	 * Ok we have allocated physical pages for the primary kernel
    649 	 * page tables
    650 	 */
    651 
    652 #ifdef VERBOSE_INIT_ARM
    653 	printf("Creating L1 page table p@0x%08x\n", (uint32_t)kernel_l1pt.pv_pa);
    654 #endif
    655 
    656 	/*
    657 	 * Now we start construction of the L1 page table
    658 	 * We start by mapping the L2 page tables into the L1.
    659 	 * This means that we can replace L1 mappings later on if necessary
    660 	 */
    661 	l1pagetable = kernel_l1pt.pv_pa;
    662 
    663 	/* Map the L2 pages tables in the L1 page table */
    664 	pmap_link_l2pt(l1pagetable, 0x00000000,
    665 	    &kernel_pt_table[KERNEL_PT_SYS]);
    666 	pmap_link_l2pt(l1pagetable, KERNEL_BASE,
    667 	    &kernel_pt_table[KERNEL_PT_KERNEL]);
    668 	pmap_link_l2pt(l1pagetable, KERNEL_BASE + 0x00400000,
    669 	    &kernel_pt_table[KERNEL_PT_KERNEL_4MB]);
    670 	for (loop = 0; loop < KERNEL_PT_VMDATA_NUM; ++loop)
    671 		pmap_link_l2pt(l1pagetable, KERNEL_VM_BASE + loop * 0x00400000,
    672 		    &kernel_pt_table[KERNEL_PT_VMDATA + loop]);
    673 	pmap_link_l2pt(l1pagetable, VMEM_VBASE,
    674 	    &kernel_pt_table[KERNEL_PT_VMEM]);
    675 
    676 	/* update the top of the kernel VM */
    677 	pmap_curmaxkvaddr =
    678 	    KERNEL_VM_BASE + (KERNEL_PT_VMDATA_NUM * 0x00400000);
    679 
    680 #ifdef VERBOSE_INIT_ARM
    681 	printf("Mapping kernel\n");
    682 #endif
    683 
    684 	/* Now we fill in the L2 pagetable for the kernel code/data */
    685 	/* XXX Kernel doesn't have to be on physical_start (!) use bootconfig XXX */
    686 	/*
    687 	 * The defines are a workaround for a recent problem that occurred
    688 	 * with ARM 610 processors and some ARM 710 processors
    689 	 * Other ARM 710 and StrongARM processors don't have a problem.
    690 	 */
    691 	if (N_GETMAGIC(kernexec[0]) == ZMAGIC) {
    692 #if defined(CPU_ARM6) || defined(CPU_ARM7)
    693 		logical = pmap_map_chunk(l1pagetable, KERNEL_TEXT_BASE,
    694 		    kernel_start, kernexec->a_text,
    695 		    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    696 #else	/* CPU_ARM6 || CPU_ARM7 */
    697 		logical = pmap_map_chunk(l1pagetable, KERNEL_TEXT_BASE,
    698 		    kernel_start, kernexec->a_text,
    699 		    VM_PROT_READ, PTE_CACHE);
    700 #endif	/* CPU_ARM6 || CPU_ARM7 */
    701 		logical += pmap_map_chunk(l1pagetable,
    702 		    KERNEL_TEXT_BASE + logical, kernel_start + logical,
    703 		    kerneldatasize - kernexec->a_text,
    704 		    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    705 	} else {	/* !ZMAGIC */
    706 		/*
    707 		 * Most likely an ELF kernel ...
    708 		 * XXX no distinction yet between read only and
    709 		 * read/write area's ...
    710 		 */
    711 		pmap_map_chunk(l1pagetable, KERNEL_TEXT_BASE,
    712 		    kernel_start, kerneldatasize,
    713 		    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    714 	};
    715 
    716 
    717 #ifdef VERBOSE_INIT_ARM
    718 	printf("Constructing L2 page tables\n");
    719 #endif
    720 
    721 	/* Map the stack pages */
    722 	pmap_map_chunk(l1pagetable, irqstack.pv_va, irqstack.pv_pa,
    723 	    IRQ_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    724 	pmap_map_chunk(l1pagetable, abtstack.pv_va, abtstack.pv_pa,
    725 	    ABT_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    726 	pmap_map_chunk(l1pagetable, undstack.pv_va, undstack.pv_pa,
    727 	    UND_STACK_SIZE * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    728 	pmap_map_chunk(l1pagetable, kernelstack.pv_va, kernelstack.pv_pa,
    729 	    UPAGES * PAGE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    730 
    731 	pmap_map_chunk(l1pagetable, kernel_l1pt.pv_va, kernel_l1pt.pv_pa,
    732 	    L1_TABLE_SIZE, VM_PROT_READ|VM_PROT_WRITE, PTE_PAGETABLE);
    733 
    734 	for (loop = 0; loop < NUM_KERNEL_PTS; ++loop) {
    735 		pmap_map_chunk(l1pagetable, kernel_pt_table[loop].pv_va,
    736 		    kernel_pt_table[loop].pv_pa, L2_TABLE_SIZE,
    737 		    VM_PROT_READ|VM_PROT_WRITE, PTE_PAGETABLE);
    738 	}
    739 
    740 	/* Now we fill in the L2 pagetable for the VRAM */
    741 	/*
    742 	 * Current architectures mean that the VRAM is always in 1
    743 	 * continuous bank.  This means that we can just map the 2 meg
    744 	 * that the VRAM would occupy.  In theory we don't need a page
    745 	 * table for VRAM, we could section map it but we would need
    746 	 * the page tables if DRAM was in use.
    747 	 * XXX please map two adjacent virtual areas to ONE physical
    748 	 * area
    749 	 */
    750 	pmap_map_chunk(l1pagetable, VMEM_VBASE, videomemory.vidm_pbase,
    751 	    videomemory.vidm_size, VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    752 	pmap_map_chunk(l1pagetable, VMEM_VBASE + videomemory.vidm_size,
    753 	    videomemory.vidm_pbase, videomemory.vidm_size,
    754 	    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    755 
    756 	/* Map the vector page. */
    757 	pmap_map_entry(l1pagetable, vector_page, systempage.pv_pa,
    758 	    VM_PROT_READ|VM_PROT_WRITE, PTE_CACHE);
    759 
    760 	/* Map the core memory needed before autoconfig */
    761 	loop = 0;
    762 	while (l1_sec_table[loop].size) {
    763 		vsize_t sz;
    764 
    765 #ifdef VERBOSE_INIT_ARM
    766 		printf("%08lx -> %08lx @ %08lx\n", l1_sec_table[loop].pa,
    767 			l1_sec_table[loop].pa + l1_sec_table[loop].size - 1,
    768 			l1_sec_table[loop].va);
    769 #endif
    770 		for (sz = 0; sz < l1_sec_table[loop].size; sz += L1_S_SIZE)
    771 			pmap_map_section(l1pagetable,
    772 			    l1_sec_table[loop].va + sz,
    773 			    l1_sec_table[loop].pa + sz,
    774 			    l1_sec_table[loop].prot,
    775 			    l1_sec_table[loop].cache);
    776 		++loop;
    777 	}
    778 
    779 	/*
    780 	 * Now we have the real page tables in place so we can switch
    781 	 * to them.  Once this is done we will be running with the
    782 	 * REAL kernel page tables.
    783 	 */
    784 
    785 	/* be a client to all domains */
    786 	cpu_domains(0x55555555);
    787 
    788 	/* Switch tables */
    789 #ifdef VERBOSE_INIT_ARM
    790 	printf("switching to new L1 page table\n");
    791 #endif
    792 
    793 	cpu_setttb(kernel_l1pt.pv_pa, true);
    794 
    795 	/*
    796 	 * We must now clean the cache again....
    797 	 * Cleaning may be done by reading new data to displace any
    798 	 * dirty data in the cache. This will have happened in cpu_setttb()
    799 	 * but since we are boot strapping the addresses used for the read
    800 	 * may have just been remapped and thus the cache could be out
    801 	 * of sync. A re-clean after the switch will cure this.
    802 	 * After booting there are no gross relocations of the kernel thus
    803 	 * this problem will not occur after initarm().
    804 	 */
    805 	cpu_idcache_wbinv_all();
    806 	cpu_tlb_flushID();
    807 	cpu_domains(DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL*2));
    808 
    809 	/*
    810 	 * Moved from cpu_startup() as data_abort_handler() references
    811 	 * this during uvm init
    812 	 */
    813 	uvm_lwp_setuarea(&lwp0, kernelstack.pv_va);
    814 
    815 	/*
    816 	 * if there is support for a serial console ...we should now
    817 	 * reattach it
    818 	 */
    819 	/*      fcomcndetach();*/
    820 
    821 	/*
    822 	 * Reflect videomemory relocation in the videomemory structure
    823 	 * and reinit console
    824 	 */
    825 	if (bootconfig.vram[0].pages == 0) {
    826 		videomemory.vidm_vbase   = VMEM_VBASE;
    827 	} else {
    828 		videomemory.vidm_vbase   = VMEM_VBASE;
    829 		bootconfig.display_start = VMEM_VBASE;
    830 	};
    831 	vidc_base = (int *) VIDC_BASE;
    832 	iomd_base =         IOMD_BASE;
    833 
    834 #ifdef FORCE_VERBOSE_INIT_ARM2
    835 	consinit();
    836 	printf("\n\n\n\n\n\n\n");
    837 #define VERBOSE_INIT_ARM
    838 #endif
    839 
    840 #ifdef VERBOSE_INIT_ARM
    841 	printf("running on the new L1 page table!\n");
    842 	printf("done.\n");
    843 #endif
    844 
    845 	arm32_vector_init(ARM_VECTORS_LOW, ARM_VEC_ALL);
    846 
    847 #ifdef VERBOSE_INIT_ARM
    848 	printf("\n");
    849 #endif
    850 
    851 	/*
    852 	 * Pages were allocated during the secondary bootstrap for the
    853 	 * stacks for different CPU modes.
    854 	 * We must now set the r13 registers in the different CPU modes to
    855 	 * point to these stacks.
    856 	 * Since the ARM stacks use STMFD etc. we must set r13 to the top end
    857 	 * of the stack memory.
    858 	 */
    859 #ifdef VERBOSE_INIT_ARM
    860 	printf("init subsystems: stacks ");
    861 	console_flush();
    862 #endif
    863 
    864 	set_stackptr(PSR_IRQ32_MODE,
    865 	    irqstack.pv_va + IRQ_STACK_SIZE * PAGE_SIZE);
    866 	set_stackptr(PSR_ABT32_MODE,
    867 	    abtstack.pv_va + ABT_STACK_SIZE * PAGE_SIZE);
    868 	set_stackptr(PSR_UND32_MODE,
    869 	    undstack.pv_va + UND_STACK_SIZE * PAGE_SIZE);
    870 #ifdef VERBOSE_INIT_ARM
    871 	printf("kstack V%08lx P%08lx\n", kernelstack.pv_va,
    872 	    kernelstack.pv_pa);
    873 #endif	/* VERBOSE_INIT_ARM */
    874 
    875 	/*
    876 	 * Well we should set a data abort handler.
    877 	 * Once things get going this will change as we will need a proper
    878 	 * handler. Until then we will use a handler that just panics but
    879 	 * tells us why.
    880 	 * Initialisation of the vectors will just panic on a data abort.
    881 	 * This just fills in a slightly better one.
    882 	 */
    883 #ifdef VERBOSE_INIT_ARM
    884 	printf("vectors ");
    885 #endif
    886 	data_abort_handler_address = (u_int)data_abort_handler;
    887 	prefetch_abort_handler_address = (u_int)prefetch_abort_handler;
    888 	undefined_handler_address = (u_int)undefinedinstruction_bounce;
    889 	console_flush();
    890 
    891 
    892 	/*
    893 	 * At last !
    894 	 * We now have the kernel in physical memory from the bottom upwards.
    895 	 * Kernel page tables are physically above this.
    896 	 * The kernel is mapped to 0xf0000000
    897 	 * The kernel data PTs will handle the mapping of
    898 	 *   0xf1000000-0xf5ffffff (80 Mb)
    899 	 * 2Meg of VRAM is mapped to 0xf7000000
    900 	 * The page tables are mapped to 0xefc00000
    901 	 * The IOMD is mapped to 0xf6000000
    902 	 * The VIDC is mapped to 0xf6100000
    903 	 * The IOMD/VIDC could be pushed up higher but i havent got
    904 	 * sufficient documentation to do so; the addresses are not
    905 	 * parametized yet and hard to read... better fix this before;
    906 	 * its pretty unforgiving.
    907 	 */
    908 
    909 	/* Initialise the undefined instruction handlers */
    910 #ifdef VERBOSE_INIT_ARM
    911 	printf("undefined ");
    912 #endif
    913 	undefined_init();
    914 	console_flush();
    915 
    916 	/* Load memory into UVM. */
    917 #ifdef VERBOSE_INIT_ARM
    918 	printf("page ");
    919 #endif
    920 	uvm_md_init();
    921 
    922 	for (loop = 0; loop < bootconfig.dramblocks; loop++) {
    923 		paddr_t start = (paddr_t)bootconfig.dram[loop].address;
    924 		paddr_t end = start + (bootconfig.dram[loop].pages * PAGE_SIZE);
    925 
    926 		if (end > physical_freestart)
    927 		{
    928 			if (start < physical_freestart)
    929 				start = physical_freestart;
    930 			if (end > physical_freeend)
    931 				end = physical_freeend;
    932 		}
    933 
    934 		if (bootconfig.dram[loop].flags & PHYSMEM_TYPE_PROCESSOR_ONLY) {
    935 			uvm_page_physload(atop(start), atop(end),
    936 					atop(start), atop(end), VM_FREELIST_DEFAULT);
    937 		} else {
    938 			uvm_page_physload(atop(start), atop(end),
    939 					atop(start), atop(end), VM_FREELIST_RPCDMA);
    940 		}
    941 	}
    942 
    943 	/* Boot strap pmap telling it where managed kernel virtual memory is */
    944 #ifdef VERBOSE_INIT_ARM
    945 	printf("pmap ");
    946 #endif
    947 	pmap_bootstrap(KERNEL_VM_BASE, KERNEL_VM_BASE + KERNEL_VM_SIZE);
    948 	console_flush();
    949 
    950 	/* Setup the IRQ system */
    951 #ifdef VERBOSE_INIT_ARM
    952 	printf("irq ");
    953 #endif
    954 	console_flush();
    955 	irq_init();
    956 #ifdef VERBOSE_INIT_ARM
    957 	printf("done.\n\n");
    958 #endif
    959 
    960 #if NVIDCVIDEO>0
    961 	consinit();		/* necessary ? */
    962 #endif
    963 
    964 	/* Talk to the user */
    965 	printf("NetBSD/acorn32 booting ... \n");
    966 
    967 	/* Tell the user if his boot loader is too old */
    968 	if ((bootconfig.magic < BOOTCONFIG_MAGIC) ||
    969 	    (bootconfig.version != BOOTCONFIG_VERSION)) {
    970 		printf("\nDETECTED AN OLD BOOTLOADER. PLEASE UPGRADE IT\n\n");
    971 		delay(5000000);
    972 	}
    973 
    974 	printf("Kernel loaded from file %s\n", bootconfig.kernelname);
    975 	printf("Kernel arg string (@%p) %s\n",
    976 	    bootconfig.args, bootconfig.args);
    977 	printf("\nBoot configuration structure reports the following "
    978 	    "memory\n");
    979 
    980 	printf(" DRAM block 0a at %08x size %08x "
    981 	    "DRAM block 0b at %08x size %08x\n\r",
    982 	    bootconfig.dram[0].address,
    983 	    bootconfig.dram[0].pages * bootconfig.pagesize,
    984 	    bootconfig.dram[1].address,
    985 	    bootconfig.dram[1].pages * bootconfig.pagesize);
    986 	printf(" DRAM block 1a at %08x size %08x "
    987 	    "DRAM block 1b at %08x size %08x\n\r",
    988 	    bootconfig.dram[2].address,
    989 	    bootconfig.dram[2].pages * bootconfig.pagesize,
    990 	    bootconfig.dram[3].address,
    991 	    bootconfig.dram[3].pages * bootconfig.pagesize);
    992 	printf(" VRAM block 0  at %08x size %08x\n\r",
    993 	    bootconfig.vram[0].address,
    994 	    bootconfig.vram[0].pages * bootconfig.pagesize);
    995 	if (hasKinetic)
    996 		printf("%s", " Kinetic memory was detected\n\r");
    997 
    998 	/*
    999 	 * Get a handle on the I2C interface so we can read
   1000 	 * the NVRAM in the real-time clock chip.
   1001 	 */
   1002 	acorn32_i2c_tag = iomdiic_bootstrap_cookie();
   1003 
   1004 	if (cmos_read(RTC_ADDR_REBOOTCNT) > 0)
   1005 		printf("Warning: REBOOTCNT = %d\n",
   1006 		    cmos_read(RTC_ADDR_REBOOTCNT));
   1007 
   1008 #ifdef CPU_SA110
   1009 	if (cputype == CPU_ID_SA110)
   1010 		rpc_sa110_cc_setup();
   1011 #endif	/* CPU_SA110 */
   1012 
   1013 #if NKSYMS || defined(DDB) || defined(MODULAR)
   1014 	ksyms_addsyms_elf(bootconfig.ksym_end - bootconfig.ksym_start,
   1015 		(void *) bootconfig.ksym_start, (void *) bootconfig.ksym_end);
   1016 #endif
   1017 
   1018 
   1019 #ifdef DDB
   1020 	db_machine_init();
   1021 	if (boothowto & RB_KDB)
   1022 		Debugger();
   1023 #endif	/* DDB */
   1024 
   1025 	/* We return the new stack pointer address */
   1026 	return(kernelstack.pv_va + USPACE_SVC_STACK_TOP);
   1027 }
   1028 
   1029 
   1030 static void
   1031 process_kernel_args(void)
   1032 {
   1033 	char *args;
   1034 
   1035 	/* Ok now we will check the arguments for interesting parameters. */
   1036 	args = bootconfig.args;
   1037 	boothowto = 0;
   1038 
   1039 	/* Only arguments itself are passed from the new bootloader */
   1040 	while (*args == ' ')
   1041 		++args;
   1042 
   1043 	boot_args = args;
   1044 	parse_mi_bootargs(boot_args);
   1045 	parse_rpc_bootargs(boot_args);
   1046 }
   1047 
   1048 
   1049 void
   1050 parse_rpc_bootargs(char *args)
   1051 {
   1052 	int integer;
   1053 
   1054 	if (get_bootconf_option(args, "videodram", BOOTOPT_TYPE_INT,
   1055 	    &integer)) {
   1056 		videodram_size = integer;
   1057 		/* Round to 4K page */
   1058 		videodram_size *= 1024;
   1059 		videodram_size = round_page(videodram_size);
   1060 		if (videodram_size > 1024*1024)
   1061 			videodram_size = 1024*1024;
   1062 	}
   1063 
   1064 #if 0
   1065 	/* XXX this I would rather have in the new bootconfig structure */
   1066 	if (get_bootconf_option(args, "kinetic", BOOTOPT_TYPE_BOOLEAN,
   1067 	    &integer)) {
   1068 		bootconfig.RPC_kinetic_card_support = 1;
   1069 	}
   1070 #endif
   1071 }
   1072 
   1073 
   1074 #ifdef CPU_SA110
   1075 
   1076 /*
   1077  * For optimal cache cleaning we need two 16K banks of
   1078  * virtual address space that NOTHING else will access
   1079  * and then we alternate the cache cleaning between the
   1080  * two banks.
   1081  * The cache cleaning code requires 2 banks aligned
   1082  * on total size boundary so the banks can be alternated by
   1083  * xorring the size bit (assumes the bank size is a power of 2)
   1084  */
   1085 extern unsigned int sa1_cache_clean_addr;
   1086 extern unsigned int sa1_cache_clean_size;
   1087 void
   1088 rpc_sa110_cc_setup(void)
   1089 {
   1090 	int loop;
   1091 	paddr_t kaddr;
   1092 
   1093 	(void) pmap_extract(pmap_kernel(), KERNEL_TEXT_BASE, &kaddr);
   1094 	const pt_entry_t npte = L2_S_PROTO | kaddr |
   1095 	    L2_S_PROT(PTE_KERNEL, VM_PROT_READ) | pte_l2_s_cache_mode;
   1096 	for (loop = 0; loop < CPU_SA110_CACHE_CLEAN_SIZE; loop += PAGE_SIZE) {
   1097 		pt_entry_t * const ptep = vtopte(sa110_cc_base + loop);
   1098 		l2pte_set(ptep, npte, 0);
   1099 		PTE_SYNC(ptep);
   1100 	}
   1101 	sa1_cache_clean_addr = sa110_cc_base;
   1102 	sa1_cache_clean_size = CPU_SA110_CACHE_CLEAN_SIZE / 2;
   1103 }
   1104 #endif	/* CPU_SA110 */
   1105 
   1106 /*
   1107  * To convert from RISC OS addresses to real CMOS addresses, do this:
   1108  *
   1109  * if (riscosaddr < 0xc0)
   1110  *         realaddr = riscosaddr + 0x40;
   1111  * else
   1112  *         realaddr = riscosaddr - 0xb0;
   1113  */
   1114 
   1115 /* Read a byte from CMOS RAM. */
   1116 int
   1117 cmos_read(int location)
   1118 {
   1119 	uint8_t val;
   1120 
   1121 	if (pcfrtc_bootstrap_read(acorn32_i2c_tag, 0x50,
   1122 	    location, &val, 1) != 0)
   1123 		return (-1);
   1124 	return (val);
   1125 }
   1126 
   1127 /* Write a byte to CMOS RAM. */
   1128 int
   1129 cmos_write(int location, int value)
   1130 {
   1131 	uint8_t val = value;
   1132 	int oldvalue, oldsum;
   1133 
   1134 	/* Get the old value and checksum. */
   1135 	if ((oldvalue = cmos_read(location)) < 0)
   1136 		return (-1);
   1137 	if ((oldsum = cmos_read(RTC_ADDR_CHECKSUM)) < 0)
   1138 		return (-1);
   1139 
   1140 	if (pcfrtc_bootstrap_write(acorn32_i2c_tag, 0x50,
   1141 	    location, &val, 1) != 0)
   1142 		return (-1);
   1143 
   1144 	/* Now update the checksum. */
   1145 	val = (uint8_t)oldsum - (uint8_t)oldvalue + val;
   1146 	return (pcfrtc_bootstrap_write(acorn32_i2c_tag, 0x50,
   1147 	    RTC_ADDR_CHECKSUM, &val, 1));
   1148 }
   1149 
   1150 /* End of machdep.c */
   1151