setup.c

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/*
 *  linux/arch/alpha/kernel/setup.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 */

/* 2.3.x bootmem, 1999 Andrea Arcangeli <[e-mail]> */

/*
 * Bootup setup stuff.
 */

#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/tty.h>
#include <linux/delay.h>
#include <linux/config.h>	/* CONFIG_ALPHA_LCA etc */
#include <linux/mc146818rtc.h>
#include <linux/console.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/ioport.h>
#include <linux/bootmem.h>

#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/blk.h>
#endif

#include <linux/notifier.h>
extern struct notifier_block *panic_notifier_list;
static int alpha_panic_event(struct notifier_block *, unsigned long, void *);
static struct notifier_block alpha_panic_block = {
	alpha_panic_event,
        NULL,
        INT_MAX /* try to do it first */
};

#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/hwrpb.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/pci.h>
#include <asm/mmu_context.h>
#include <asm/console.h>

#include "proto.h"
#include "pci_impl.h"


struct hwrpb_struct *hwrpb;
unsigned long srm_hae;

/* Which processor we booted from.  */
int boot_cpuid;

/* Using SRM callbacks for initial console output. This works from
   setup_arch() time through the end of init_IRQ(), as those places
   are under our control.

   By default, OFF; set it with a bootcommand arg of "srmcons".
*/
int srmcons_output = 0;

/* Enforce a memory size limit; useful for testing. By default, none. */
unsigned long mem_size_limit = 0;

#ifdef CONFIG_ALPHA_GENERIC
struct alpha_machine_vector alpha_mv;
int alpha_using_srm;
#endif

unsigned char aux_device_present = 0xaa;

#define N(a) (sizeof(a)/sizeof(a[0]))

static struct alpha_machine_vector *get_sysvec(long, long, long);
static struct alpha_machine_vector *get_sysvec_byname(const char *);
static void get_sysnames(long, long, char **, char **);

/*
 * This is setup by the secondary bootstrap loader.  Because
 * the zero page is zeroed out as soon as the vm system is
 * initialized, we need to copy things out into a more permanent
 * place.
 */
#define PARAM			ZERO_PGE
#define COMMAND_LINE		((char*)(PARAM + 0x0000))
#define COMMAND_LINE_SIZE	256
#define INITRD_START		(*(unsigned long *) (PARAM+0x100))
#define INITRD_SIZE		(*(unsigned long *) (PARAM+0x108))

static char command_line[COMMAND_LINE_SIZE];
char saved_command_line[COMMAND_LINE_SIZE];

/*
 * The format of "screen_info" is strange, and due to early
 * i386-setup code. This is just enough to make the console
 * code think we're on a VGA color display.
 */

struct screen_info screen_info = {
	orig_x: 0,
	orig_y: 25,
	orig_video_cols: 80,
	orig_video_lines: 25,
	orig_video_isVGA: 1,
	orig_video_points: 16
};

/*
 * The direct map I/O window, if any.  This should be the same
 * for all busses, since it's used by virt_to_bus.
 */

unsigned long __direct_map_base;
unsigned long __direct_map_size;

/*
 * Declare all of the machine vectors.
 */

/* GCC 2.7.2 (on alpha at least) is lame.  It does not support either 
   __attribute__((weak)) or #pragma weak.  Bypass it and talk directly
   to the assembler.  */

#define WEAK(X) \
	extern struct alpha_machine_vector X; \
	asm(".weak "#X)

WEAK(alcor_mv);
WEAK(alphabook1_mv);
WEAK(avanti_mv);
WEAK(cabriolet_mv);
WEAK(clipper_mv);
WEAK(dp264_mv);
WEAK(eb164_mv);
WEAK(eb64p_mv);
WEAK(eb66_mv);
WEAK(eb66p_mv);
WEAK(eiger_mv);
WEAK(jensen_mv);
WEAK(lx164_mv);
WEAK(miata_mv);
WEAK(mikasa_mv);
WEAK(mikasa_primo_mv);
WEAK(monet_mv);
WEAK(nautilus_mv);
WEAK(noname_mv);
WEAK(noritake_mv);
WEAK(noritake_primo_mv);
WEAK(p2k_mv);
WEAK(pc164_mv);
WEAK(privateer_mv);
WEAK(rawhide_mv);
WEAK(ruffian_mv);
WEAK(rx164_mv);
WEAK(sable_mv);
WEAK(sable_gamma_mv);
WEAK(sx164_mv);
WEAK(takara_mv);
WEAK(webbrick_mv);
WEAK(wildfire_mv);
WEAK(xl_mv);
WEAK(xlt_mv);

#undef WEAK

/*
 * I/O resources inherited from PeeCees.  Except for perhaps the
 * turbochannel alphas, everyone has these on some sort of SuperIO chip.
 *
 * ??? If this becomes less standard, move the struct out into the
 * machine vector.
 */

static void __init
reserve_std_resources(void)
{
	static struct resource standard_io_resources[] = {
		{ "rtc", -1, -1 },
        	{ "dma1", 0x00, 0x1f },
        	{ "pic1", 0x20, 0x3f },
        	{ "timer", 0x40, 0x5f },
        	{ "keyboard", 0x60, 0x6f },
        	{ "dma page reg", 0x80, 0x8f },
        	{ "pic2", 0xa0, 0xbf },
        	{ "dma2", 0xc0, 0xdf },
	};

	struct resource *io = &ioport_resource;
	long i;

	if (hose_head) {
		struct pci_controler *hose;
		for (hose = hose_head; hose; hose = hose->next)
			if (hose->index == 0) {
				io = hose->io_space;
				break;
			}
	}

	/* Fix up for the Jensen's queer RTC placement.  */
	standard_io_resources[0].start = RTC_PORT(0);
	standard_io_resources[0].end = RTC_PORT(0) + 0x10;

	for (i = 0; i < N(standard_io_resources); ++i)
		request_resource(io, standard_io_resources+i);
}

#define PFN_UP(x)	(((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
#define PFN_DOWN(x)	((x) >> PAGE_SHIFT)
#define PFN_PHYS(x)	((x) << PAGE_SHIFT)
#define PFN_MAX		PFN_DOWN(0x80000000)
#define for_each_mem_cluster(memdesc, cluster, i)		\
	for ((cluster) = (memdesc)->cluster, (i) = 0;		\
	     (i) < (memdesc)->numclusters; (i)++, (cluster)++)

static unsigned long __init
get_mem_size_limit(char *s)
{
        unsigned long end = 0;
        char *from = s;

        end = simple_strtoul(from, &from, 0);
        if ( *from == 'K' || *from == 'k' ) {
                end = end << 10;
                from++;
        } else if ( *from == 'M' || *from == 'm' ) {
                end = end << 20;
                from++;
        } else if ( *from == 'G' || *from == 'g' ) {
                end = end << 30;
                from++;
        }
        return end >> PAGE_SHIFT; /* Return the PFN of the limit. */
}

static void __init
setup_memory(void *kernel_end)
{
	struct memclust_struct * cluster;
	struct memdesc_struct * memdesc;
	unsigned long start_kernel_pfn, end_kernel_pfn;
	unsigned long bootmap_size, bootmap_pages, bootmap_start;
	unsigned long start, end;
	int i;

	/* Find free clusters, and init and free the bootmem accordingly.  */
	memdesc = (struct memdesc_struct *)
	  (hwrpb->mddt_offset + (unsigned long) hwrpb);

	for_each_mem_cluster(memdesc, cluster, i) {
		printk("memcluster %d, usage %01lx, start %8lu, end %8lu\n",
		       i, cluster->usage, cluster->start_pfn,
		       cluster->start_pfn + cluster->numpages);

		/* Bit 0 is console/PALcode reserved.  Bit 1 is
		   non-volatile memory -- we might want to mark
		   this for later.  */
		if (cluster->usage & 3)
			continue;

		end = cluster->start_pfn + cluster->numpages;
		if (end > max_low_pfn)
			max_low_pfn = end;
	}

	if (mem_size_limit && max_low_pfn >= mem_size_limit)
	{
		printk("setup: forcing memory size to %ldK (from %ldK).\n",
		       mem_size_limit << (PAGE_SHIFT - 10),
		       max_low_pfn    << (PAGE_SHIFT - 10));
		max_low_pfn = mem_size_limit;
	}

	/* Find the bounds of kernel memory.  */
	start_kernel_pfn = PFN_DOWN(KERNEL_START_PHYS);
	end_kernel_pfn = PFN_UP(virt_to_phys(kernel_end));
	bootmap_start = -1;

 try_again:
	if (max_low_pfn <= end_kernel_pfn)
		panic("not enough memory to boot");

	/* We need to know how many physically contiguous pages
	   we'll need for the bootmap.  */
	bootmap_pages = bootmem_bootmap_pages(max_low_pfn);

	/* Now find a good region where to allocate the bootmap.  */
	for_each_mem_cluster(memdesc, cluster, i) {
		if (cluster->usage & 3)
			continue;

		start = cluster->start_pfn;
		end = start + cluster->numpages;
		if (start >= max_low_pfn)
			continue;
		if (end > max_low_pfn)
			end = max_low_pfn;
		if (start < start_kernel_pfn) {
			if (end > end_kernel_pfn
			    && end - end_kernel_pfn >= bootmap_pages) {
				bootmap_start = end_kernel_pfn;
				break;
			} else if (end > start_kernel_pfn)
				end = start_kernel_pfn;
		} else if (start < end_kernel_pfn)
			start = end_kernel_pfn;
		if (end - start >= bootmap_pages) {
			bootmap_start = start;
			break;
		}
	}

	if (bootmap_start == -1) {
		max_low_pfn >>= 1;
		goto try_again;
	}

	/* Allocate the bootmap and mark the whole MM as reserved.  */
	bootmap_size = init_bootmem(bootmap_start, max_low_pfn);

	/* Mark the free regions.  */
	for_each_mem_cluster(memdesc, cluster, i) {
		if (cluster->usage & 3)
			continue;

		start = cluster->start_pfn;
		end = cluster->start_pfn + cluster->numpages;
		if (start >= max_low_pfn)
			continue;
		if (end > max_low_pfn)
			end = max_low_pfn;
		if (start < start_kernel_pfn) {
			if (end > end_kernel_pfn) {
				free_bootmem(PFN_PHYS(start),
					     (PFN_PHYS(start_kernel_pfn)
					      - PFN_PHYS(start)));
				printk("freeing pages %ld:%ld\n",
				       start, start_kernel_pfn);
				start = end_kernel_pfn;
			} else if (end > start_kernel_pfn)
				end = start_kernel_pfn;
		} else if (start < end_kernel_pfn)
			start = end_kernel_pfn;
		if (start >= end)
			continue;

		free_bootmem(PFN_PHYS(start), PFN_PHYS(end) - PFN_PHYS(start));
		printk("freeing pages %ld:%ld\n", start, end);
	}

	/* Reserve the bootmap memory.  */
	reserve_bootmem(PFN_PHYS(bootmap_start), bootmap_size);

#ifdef CONFIG_BLK_DEV_INITRD
	initrd_start = INITRD_START;
	if (initrd_start) {
		initrd_end = initrd_start+INITRD_SIZE;
		printk("Initial ramdisk at: 0x%p (%lu bytes)\n",
		       (void *) initrd_start, INITRD_SIZE);

		if ((void *)initrd_end > phys_to_virt(PFN_PHYS(max_low_pfn))) {
			printk("initrd extends beyond end of memory "
			       "(0x%08lx > 0x%p)\ndisabling initrd\n",
			       initrd_end,
			       phys_to_virt(PFN_PHYS(max_low_pfn)));
			initrd_start = initrd_end = 0;
		} else {
			reserve_bootmem(virt_to_phys((void *)initrd_start),
					INITRD_SIZE);
		}
	}
#endif /* CONFIG_BLK_DEV_INITRD */
}

int __init
page_is_ram(unsigned long pfn)
{
	struct memclust_struct * cluster;
	struct memdesc_struct * memdesc;
	int i;

	memdesc = (struct memdesc_struct *)
		(hwrpb->mddt_offset + (unsigned long) hwrpb);
	for_each_mem_cluster(memdesc, cluster, i)
	{
		if (pfn >= cluster->start_pfn  &&
		    pfn < cluster->start_pfn + cluster->numpages) {
			return (cluster->usage & 3) ? 0 : 1;
		}
	}

	return 0;
}

#undef PFN_UP
#undef PFN_DOWN
#undef PFN_PHYS
#undef PFN_MAX

#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SRM)
/*
 *      Manage the SRM callbacks as a "console".
 */
static struct console srmcons;

void __init register_srm_console(void)
{
        register_console(&srmcons);
}

void __init unregister_srm_console(void)
{
        unregister_console(&srmcons);
}

static void srm_console_write(struct console *co, const char *s,
                                unsigned count)
{
	srm_printk(s);
}

static kdev_t srm_console_device(struct console *c)
{
  /* Huh? */
        return MKDEV(TTY_MAJOR, 64 + c->index);
}

static int srm_console_wait_key(struct console *co)
{
  /* Huh? */
	return 1;
}

static int __init srm_console_setup(struct console *co, char *options)
{
	return 1;
}

static struct console srmcons = {
	name:		"srm0",
	write:		srm_console_write,
	device:		srm_console_device,
	wait_key:	srm_console_wait_key,
	setup:		srm_console_setup,
	flags:		CON_PRINTBUFFER | CON_ENABLED, /* fake it out */
	index:		-1,
};

#else
void __init register_srm_console(void)
{
}
void __init unregister_srm_console(void)
{
}
#endif

void __init
setup_arch(char **cmdline_p)
{
	extern char _end[];

	struct alpha_machine_vector *vec = NULL;
	struct percpu_struct *cpu;
	char *type_name, *var_name, *p;
	void *kernel_end = _end; /* end of kernel */

	hwrpb = (struct hwrpb_struct*) __va(INIT_HWRPB->phys_addr);
	boot_cpuid = hard_smp_processor_id();

	/* Register a call for panic conditions. */
	notifier_chain_register(&panic_notifier_list, &alpha_panic_block);

#ifdef CONFIG_ALPHA_GENERIC
	/* Assume that we've booted from SRM if we havn't booted from MILO.
	   Detect the later by looking for "MILO" in the system serial nr.  */
	alpha_using_srm = strncmp((const char *)hwrpb->ssn, "MILO", 4) != 0;
#endif

	/* If we are using SRM, we want to allow callbacks
	   as early as possible, so do this NOW, and then
	   they should work immediately thereafter.
	*/
	kernel_end = callback_init(kernel_end);

	/* 
	 * Locate the command line.
	 */
	/* Hack for Jensen... since we're restricted to 8 or 16 chars for
	   boot flags depending on the boot mode, we need some shorthand.
	   This should do for installation.  */
	if (strcmp(COMMAND_LINE, "INSTALL") == 0) {
		strcpy(command_line, "root=/dev/fd0 load_ramdisk=1");
	} else {
		strncpy(command_line, COMMAND_LINE, sizeof command_line);
		command_line[sizeof(command_line)-1] = 0;
	}
	strcpy(saved_command_line, command_line);
	*cmdline_p = command_line;

	/* 
	 * Process command-line arguments.
	 */
	for (p = strtok(command_line, " \t"); p ; p = strtok(NULL, " \t")) {
		if (strncmp(p, "alpha_mv=", 9) == 0) {
			vec = get_sysvec_byname(p+9);
			continue;
		}
		if (strncmp(p, "cycle=", 6) == 0) {
			est_cycle_freq = simple_strtol(p+6, NULL, 0);
			continue;
		}
		if (strncmp(p, "mem=", 4) == 0) {
			mem_size_limit = get_mem_size_limit(p+4);
			continue;
		}
		if (strncmp(p, "srmcons", 7) == 0) {
			srmcons_output = 1;
			continue;
		}
	}

	/* Replace the command line, now that we've killed it with strtok.  */
	strcpy(command_line, saved_command_line);

	/* If we want SRM console printk echoing early, do it now. */
	if (alpha_using_srm && srmcons_output) {
		register_srm_console();
	}

	/*
	 * Indentify and reconfigure for the current system.
	 */
	get_sysnames(hwrpb->sys_type, hwrpb->sys_variation,
		     &type_name, &var_name);
	if (*var_name == '0')
		var_name = "";

	if (!vec) {
		cpu = (struct percpu_struct*)
			((char*)hwrpb + hwrpb->processor_offset);
		vec = get_sysvec(hwrpb->sys_type, hwrpb->sys_variation,
				 cpu->type);
	}

	if (!vec) {
		panic("Unsupported system type: %s%s%s (%ld %ld)\n",