rsrc_mgr.c

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

    Resource management routines

    rsrc_mgr.c 1.79 2000/08/30 20:23:58

    The contents of this file are subject to the Mozilla Public
    License Version 1.1 (the "License"); you may not use this file
    except in compliance with the License. You may obtain a copy of
    the License at http://www.mozilla.org/MPL/

    Software distributed under the License is distributed on an "AS
    IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
    implied. See the License for the specific language governing
    rights and limitations under the License.

    The initial developer of the original code is David A. Hinds
    <[e-mail]>.  Portions created by David A. Hinds
    are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.

    Alternatively, the contents of this file may be used under the
    terms of the GNU Public License version 2 (the "GPL"), in which
    case the provisions of the GPL are applicable instead of the
    above.  If you wish to allow the use of your version of this file
    only under the terms of the GPL and not to allow others to use
    your version of this file under the MPL, indicate your decision
    by deleting the provisions above and replace them with the notice
    and other provisions required by the GPL.  If you do not delete
    the provisions above, a recipient may use your version of this
    file under either the MPL or the GPL.
    
======================================================================*/

#define __NO_VERSION__

#include <linux/config.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/malloc.h>
#include <linux/ioport.h>
#include <linux/timer.h>
#include <asm/irq.h>
#include <asm/io.h>

#include <pcmcia/cs_types.h>
#include <pcmcia/ss.h>
#include <pcmcia/cs.h>
#include <pcmcia/bulkmem.h>
#include <pcmcia/cistpl.h>
#include "cs_internal.h"
#include "rsrc_mgr.h"

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

/* Parameters that can be set with 'insmod' */

#define INT_MODULE_PARM(n, v) static int n = v; MODULE_PARM(n, "i")

INT_MODULE_PARM(probe_mem,	1);		/* memory probe? */
#ifdef CONFIG_ISA
INT_MODULE_PARM(probe_io,	1);		/* IO port probe? */
INT_MODULE_PARM(mem_limit,	0x10000);
#endif

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

    The resource_map_t structures are used to track what resources are
    available for allocation for PC Card devices.

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

typedef struct resource_map_t {
    u_long			base, num;
    struct resource_map_t	*next;
} resource_map_t;

/* Memory resource database */
static resource_map_t mem_db = { 0, 0, &mem_db };

/* IO port resource database */
static resource_map_t io_db = { 0, 0, &io_db };

#ifdef CONFIG_ISA

typedef struct irq_info_t {
    u_int			Attributes;
    int				time_share, dyn_share;
    struct socket_info_t	*Socket;
} irq_info_t;

/* Table of IRQ assignments */
static irq_info_t irq_table[NR_IRQS] = { { 0, 0, 0 }, /* etc */ };

#endif

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

    Linux resource management extensions

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

#define check_io_resource(b,n)	check_resource(&ioport_resource, (b), (n))
#define check_mem_resource(b,n)	check_resource(&iomem_resource, (b), (n))

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

    These manage the internal databases of available resources.
    
======================================================================*/

static int add_interval(resource_map_t *map, u_long base, u_long num)
{
    resource_map_t *p, *q;

    for (p = map; ; p = p->next) {
	if ((p != map) && (p->base+p->num-1 >= base))
	    return -1;
	if ((p->next == map) || (p->next->base > base+num-1))
	    break;
    }
    q = kmalloc(sizeof(resource_map_t), GFP_KERNEL);
    if (!q) return CS_OUT_OF_RESOURCE;
    q->base = base; q->num = num;
    q->next = p->next; p->next = q;
    return CS_SUCCESS;
}

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

static int sub_interval(resource_map_t *map, u_long base, u_long num)
{
    resource_map_t *p, *q;

    for (p = map; ; p = q) {
	q = p->next;
	if (q == map)
	    break;
	if ((q->base+q->num > base) && (base+num > q->base)) {
	    if (q->base >= base) {
		if (q->base+q->num <= base+num) {
		    /* Delete whole block */
		    p->next = q->next;
		    kfree(q);
		    /* don't advance the pointer yet */
		    q = p;
		} else {
		    /* Cut off bit from the front */
		    q->num = q->base + q->num - base - num;
		    q->base = base + num;
		}
	    } else if (q->base+q->num <= base+num) {
		/* Cut off bit from the end */
		q->num = base - q->base;
	    } else {
		/* Split the block into two pieces */
		p = kmalloc(sizeof(resource_map_t), GFP_KERNEL);
		if (!p) return CS_OUT_OF_RESOURCE;
		p->base = base+num;
		p->num = q->base+q->num - p->base;
		q->num = base - q->base;
		p->next = q->next ; q->next = p;
	    }
	}
    }
    return CS_SUCCESS;
}

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

    These routines examine a region of IO or memory addresses to
    determine what ranges might be genuinely available.
    
======================================================================*/

#ifdef CONFIG_ISA
static void do_io_probe(ioaddr_t base, ioaddr_t num)
{
    
    ioaddr_t i, j, bad, any;
    u_char *b, hole, most;
    
    printk(KERN_INFO "cs: IO port probe 0x%04x-0x%04x:",
	   base, base+num-1);
    
    /* First, what does a floating port look like? */
    b = kmalloc(256, GFP_KERNEL);
    memset(b, 0, 256);
    for (i = base, most = 0; i < base+num; i += 8) {
	if (check_io_resource(i, 8))
	    continue;
	hole = inb(i);
	for (j = 1; j < 8; j++)
	    if (inb(i+j) != hole) break;
	if ((j == 8) && (++b[hole] > b[most]))
	    most = hole;
	if (b[most] == 127) break;
    }
    kfree(b);

    bad = any = 0;
    for (i = base; i < base+num; i += 8) {
	if (check_io_resource(i, 8))
	    continue;
	for (j = 0; j < 8; j++)
	    if (inb(i+j) != most) break;
	if (j < 8) {
	    if (!any)
		printk(" excluding");
	    if (!bad)
		bad = any = i;
	} else {
	    if (bad) {
		sub_interval(&io_db, bad, i-bad);
		printk(" %#04x-%#04x", bad, i-1);
		bad = 0;
	    }
	}
    }
    if (bad) {
	if ((num > 16) && (bad == base) && (i == base+num)) {
	    printk(" nothing: probe failed.\n");
	    return;
	} else {
	    sub_interval(&io_db, bad, i-bad);
	    printk(" %#04x-%#04x", bad, i-1);
	}
    }
    
    printk(any ? "\n" : " clean.\n");
}
#endif

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

    The memory probe.  If the memory list includes a 64K-aligned block
    below 1MB, we probe in 64K chunks, and as soon as we accumulate at
    least mem_limit free space, we quit.
    
======================================================================*/

static int do_mem_probe(u_long base, u_long num,
			int (*is_valid)(u_long), int (*do_cksum)(u_long))
{
    u_long i, j, bad, fail, step;

    printk(KERN_INFO "cs: memory probe 0x%06lx-0x%06lx:",
	   base, base+num-1);
    bad = fail = 0;
    step = (num < 0x20000) ? 0x2000 : ((num>>4) & ~0x1fff);
    for (i = base; i < base+num; i = j + step) {
	if (!fail) {	
	    for (j = i; j < base+num; j += step)
		if ((check_mem_resource(j, step) == 0) && is_valid(j))
		    break;
	    fail = ((i == base) && (j == base+num));
	}
	if (fail) {
	    for (j = i; j < base+num; j += 2*step)
		if ((check_mem_resource(j, 2*step) == 0) &&
		    do_cksum(j) && do_cksum(j+step))
		    break;
	}
	if (i != j) {
	    if (!bad) printk(" excluding");
	    printk(" %#05lx-%#05lx", i, j-1);
	    sub_interval(&mem_db, i, j-i);
	    bad += j-i;
	}
    }
    printk(bad ? "\n" : " clean.\n");
    return (num - bad);
}

#ifdef CONFIG_ISA

static u_long inv_probe(int (*is_valid)(u_long),
			int (*do_cksum)(u_long),
			resource_map_t *m)
{
    u_long ok;
    if (m == &mem_db)
	return 0;
    ok = inv_probe(is_valid, do_cksum, m->next);
    if (ok) {
	if (m->base >= 0x100000)
	    sub_interval(&mem_db, m->base, m->num);
	return ok;
    }
    if (m->base < 0x100000)
	return 0;
    return do_mem_probe(m->base, m->num, is_valid, do_cksum);
}

void validate_mem(int (*is_valid)(u_long), int (*do_cksum)(u_long),
		  int force_low)
{
    resource_map_t *m, *n;
    static u_char order[] = { 0xd0, 0xe0, 0xc0, 0xf0 };
    static int hi = 0, lo = 0;
    u_long b, i, ok = 0;
    
    if (!probe_mem) return;
    /* We do up to four passes through the list */
    if (!force_low) {
	if (hi++ || (inv_probe(is_valid, do_cksum, mem_db.next) > 0))
	    return;
	printk(KERN_NOTICE "cs: warning: no high memory space "
	       "available!\n");
    }
    if (lo++) return;
    for (m = mem_db.next; m != &mem_db; m = n) {
	n = m->next;
	/* Only probe < 1 MB */
	if (m->base >= 0x100000) continue;
	if ((m->base | m->num) & 0xffff) {
	    ok += do_mem_probe(m->base, m->num, is_valid, do_cksum);
	    continue;
	}
	/* Special probe for 64K-aligned block */
	for (i = 0; i < 4; i++) {
	    b = order[i] << 12;
	    if ((b >= m->base) && (b+0x10000 <= m->base+m->num)) {
		if (ok >= mem_limit)
		    sub_interval(&mem_db, b, 0x10000);
		else
		    ok += do_mem_probe(b, 0x10000, is_valid, do_cksum);
	    }
	}
    }
}