FreeBSD/Linux Kernel Cross Reference
sys/dev/acpica/acpi_resource.c

     /*-
      * Copyright (c) 2000 Michael Smith
      * Copyright (c) 2000 BSDi
      * 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.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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.
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD: releng/10.3/sys/dev/acpica/acpi_resource.c 281687 2015-04-18 08:01:12Z jkim $");
    
    #include "opt_acpi.h"
    #include <sys/param.h>
    #include <sys/kernel.h>
    #include <sys/bus.h>
    #include <sys/limits.h>
    #include <sys/malloc.h>
    #include <sys/module.h>
    
    #include <machine/bus.h>
    #include <machine/resource.h>
    #include <sys/rman.h>
    
    #include <contrib/dev/acpica/include/acpi.h>
    #include <contrib/dev/acpica/include/accommon.h>
    
    #include <dev/acpica/acpivar.h>
    
    /* Hooks for the ACPI CA debugging infrastructure */
    #define _COMPONENT      ACPI_BUS
    ACPI_MODULE_NAME("RESOURCE")
    
    struct lookup_irq_request {
        ACPI_RESOURCE *acpi_res;
        struct resource *res;
        int         counter;
        int         rid;
        int         found;
    };
    
    static ACPI_STATUS
    acpi_lookup_irq_handler(ACPI_RESOURCE *res, void *context)
    {
        struct lookup_irq_request *req;
        size_t len;
        u_int irqnum, irq;
    
        switch (res->Type) {
        case ACPI_RESOURCE_TYPE_IRQ:
            irqnum = res->Data.Irq.InterruptCount;
            irq = res->Data.Irq.Interrupts[0];
            len = ACPI_RS_SIZE(ACPI_RESOURCE_IRQ);
            break;
        case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
            irqnum = res->Data.ExtendedIrq.InterruptCount;
            irq = res->Data.ExtendedIrq.Interrupts[0];
            len = ACPI_RS_SIZE(ACPI_RESOURCE_EXTENDED_IRQ);
            break;
        default:
            return (AE_OK);
        }
        if (irqnum != 1)
            return (AE_OK);
        req = (struct lookup_irq_request *)context;
        if (req->counter != req->rid) {
            req->counter++;
            return (AE_OK);
        }
        req->found = 1;
        KASSERT(irq == rman_get_start(req->res),
            ("IRQ resources do not match"));
        bcopy(res, req->acpi_res, len);
        return (AE_CTRL_TERMINATE);
    }
    
    ACPI_STATUS
    acpi_lookup_irq_resource(device_t dev, int rid, struct resource *res,
        ACPI_RESOURCE *acpi_res)
    {
        struct lookup_irq_request req;
       ACPI_STATUS status;
   
       req.acpi_res = acpi_res;
       req.res = res;
       req.counter = 0;
       req.rid = rid;
       req.found = 0;
       status = AcpiWalkResources(acpi_get_handle(dev), "_CRS",
           acpi_lookup_irq_handler, &req);
       if (ACPI_SUCCESS(status) && req.found == 0)
           status = AE_NOT_FOUND;
       return (status);
   }
   
   void
   acpi_config_intr(device_t dev, ACPI_RESOURCE *res)
   {
       u_int irq;
       int pol, trig;
   
       switch (res->Type) {
       case ACPI_RESOURCE_TYPE_IRQ:
           KASSERT(res->Data.Irq.InterruptCount == 1,
               ("%s: multiple interrupts", __func__));
           irq = res->Data.Irq.Interrupts[0];
           trig = res->Data.Irq.Triggering;
           pol = res->Data.Irq.Polarity;
           break;
       case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
           KASSERT(res->Data.ExtendedIrq.InterruptCount == 1,
               ("%s: multiple interrupts", __func__));
           irq = res->Data.ExtendedIrq.Interrupts[0];
           trig = res->Data.ExtendedIrq.Triggering;
           pol = res->Data.ExtendedIrq.Polarity;
           break;
       default:
           panic("%s: bad resource type %u", __func__, res->Type);
       }
   
   #if defined(__amd64__) || defined(__i386__)
       /*
        * XXX: Certain BIOSes have buggy AML that specify an IRQ that is
        * edge-sensitive and active-lo.  However, edge-sensitive IRQs
        * should be active-hi.  Force IRQs with an ISA IRQ value to be
        * active-hi instead.
        */
       if (irq < 16 && trig == ACPI_EDGE_SENSITIVE && pol == ACPI_ACTIVE_LOW)
           pol = ACPI_ACTIVE_HIGH;
   #endif
       BUS_CONFIG_INTR(dev, irq, (trig == ACPI_EDGE_SENSITIVE) ?
           INTR_TRIGGER_EDGE : INTR_TRIGGER_LEVEL, (pol == ACPI_ACTIVE_HIGH) ?
           INTR_POLARITY_HIGH : INTR_POLARITY_LOW);
   }
   
   struct acpi_resource_context {
       struct acpi_parse_resource_set *set;
       device_t    dev;
       void        *context;
   };
   
   #ifdef ACPI_DEBUG_OUTPUT
   static const char *
   acpi_address_range_name(UINT8 ResourceType)
   {
       static char buf[16];
   
       switch (ResourceType) {
       case ACPI_MEMORY_RANGE:
               return ("Memory");
       case ACPI_IO_RANGE:
               return ("IO");
       case ACPI_BUS_NUMBER_RANGE:
               return ("Bus Number");
       default:
               snprintf(buf, sizeof(buf), "type %u", ResourceType);
               return (buf);
       }
   }
   #endif
               
   static ACPI_STATUS
   acpi_parse_resource(ACPI_RESOURCE *res, void *context)
   {
       struct acpi_parse_resource_set *set;
       struct acpi_resource_context *arc;
       UINT64 min, max, length, gran;
       const char *name;
       device_t dev;
   
       arc = context;
       dev = arc->dev;
       set = arc->set;
   
       switch (res->Type) {
       case ACPI_RESOURCE_TYPE_END_TAG:
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "EndTag\n"));
           break;
       case ACPI_RESOURCE_TYPE_FIXED_IO:
           if (res->Data.FixedIo.AddressLength <= 0)
               break;
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "FixedIo 0x%x/%d\n",
               res->Data.FixedIo.Address, res->Data.FixedIo.AddressLength));
           set->set_ioport(dev, arc->context, res->Data.FixedIo.Address,
               res->Data.FixedIo.AddressLength);
           break;
       case ACPI_RESOURCE_TYPE_IO:
           if (res->Data.Io.AddressLength <= 0)
               break;
           if (res->Data.Io.Minimum == res->Data.Io.Maximum) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Io 0x%x/%d\n",
                   res->Data.Io.Minimum, res->Data.Io.AddressLength));
               set->set_ioport(dev, arc->context, res->Data.Io.Minimum,
                   res->Data.Io.AddressLength);
           } else {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Io 0x%x-0x%x/%d\n",
                   res->Data.Io.Minimum, res->Data.Io.Maximum,
                   res->Data.Io.AddressLength));
               set->set_iorange(dev, arc->context, res->Data.Io.Minimum,
                   res->Data.Io.Maximum, res->Data.Io.AddressLength,
                   res->Data.Io.Alignment);
           }
           break;
       case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
           if (res->Data.FixedMemory32.AddressLength <= 0)
               break;
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "FixedMemory32 0x%x/%d\n",
               res->Data.FixedMemory32.Address,
               res->Data.FixedMemory32.AddressLength));
           set->set_memory(dev, arc->context, res->Data.FixedMemory32.Address, 
               res->Data.FixedMemory32.AddressLength);
           break;
       case ACPI_RESOURCE_TYPE_MEMORY32:
           if (res->Data.Memory32.AddressLength <= 0)
               break;
           if (res->Data.Memory32.Minimum == res->Data.Memory32.Maximum) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Memory32 0x%x/%d\n",
                   res->Data.Memory32.Minimum, res->Data.Memory32.AddressLength));
               set->set_memory(dev, arc->context, res->Data.Memory32.Minimum,
                   res->Data.Memory32.AddressLength);
           } else {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Memory32 0x%x-0x%x/%d\n",
                   res->Data.Memory32.Minimum, res->Data.Memory32.Maximum,
                   res->Data.Memory32.AddressLength));
               set->set_memoryrange(dev, arc->context, res->Data.Memory32.Minimum,
                   res->Data.Memory32.Maximum, res->Data.Memory32.AddressLength,
                   res->Data.Memory32.Alignment);
           }
           break;
       case ACPI_RESOURCE_TYPE_MEMORY24:
           if (res->Data.Memory24.AddressLength <= 0)
               break;
           if (res->Data.Memory24.Minimum == res->Data.Memory24.Maximum) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Memory24 0x%x/%d\n",
                   res->Data.Memory24.Minimum, res->Data.Memory24.AddressLength));
               set->set_memory(dev, arc->context, res->Data.Memory24.Minimum,
                   res->Data.Memory24.AddressLength);
           } else {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "Memory24 0x%x-0x%x/%d\n",
                   res->Data.Memory24.Minimum, res->Data.Memory24.Maximum,
                   res->Data.Memory24.AddressLength));
               set->set_memoryrange(dev, arc->context, res->Data.Memory24.Minimum,
                   res->Data.Memory24.Maximum, res->Data.Memory24.AddressLength,
                   res->Data.Memory24.Alignment);
           }
           break;
       case ACPI_RESOURCE_TYPE_IRQ:
           /*
            * from 1.0b 6.4.2 
            * "This structure is repeated for each separate interrupt
            * required"
            */
           set->set_irq(dev, arc->context, res->Data.Irq.Interrupts,
               res->Data.Irq.InterruptCount, res->Data.Irq.Triggering,
               res->Data.Irq.Polarity);
           break;
       case ACPI_RESOURCE_TYPE_DMA:
           /*
            * from 1.0b 6.4.3 
            * "This structure is repeated for each separate DMA channel
            * required"
            */
           set->set_drq(dev, arc->context, res->Data.Dma.Channels,
               res->Data.Dma.ChannelCount);
           break;
       case ACPI_RESOURCE_TYPE_START_DEPENDENT:
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "start dependent functions\n"));
           set->set_start_dependent(dev, arc->context,
               res->Data.StartDpf.CompatibilityPriority);
           break;
       case ACPI_RESOURCE_TYPE_END_DEPENDENT:
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "end dependent functions\n"));
           set->set_end_dependent(dev, arc->context);
           break;
       case ACPI_RESOURCE_TYPE_ADDRESS16:
       case ACPI_RESOURCE_TYPE_ADDRESS32:
       case ACPI_RESOURCE_TYPE_ADDRESS64:
       case ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64:
           switch (res->Type) {
           case ACPI_RESOURCE_TYPE_ADDRESS16:
               gran = res->Data.Address16.Address.Granularity;
               min = res->Data.Address16.Address.Minimum;
               max = res->Data.Address16.Address.Maximum;
               length = res->Data.Address16.Address.AddressLength;
               name = "Address16";
               break;
           case ACPI_RESOURCE_TYPE_ADDRESS32:
               gran = res->Data.Address32.Address.Granularity;
               min = res->Data.Address32.Address.Minimum;
               max = res->Data.Address32.Address.Maximum;
               length = res->Data.Address32.Address.AddressLength;
               name = "Address32";
               break;
           case ACPI_RESOURCE_TYPE_ADDRESS64:
               gran = res->Data.Address64.Address.Granularity;
               min = res->Data.Address64.Address.Minimum;
               max = res->Data.Address64.Address.Maximum;
               length = res->Data.Address64.Address.AddressLength;
               name = "Address64";
               break;
           default:
               KASSERT(res->Type == ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64,
                   ("should never happen"));
               gran = res->Data.ExtAddress64.Address.Granularity;
               min = res->Data.ExtAddress64.Address.Minimum;
               max = res->Data.ExtAddress64.Address.Maximum;
               length = res->Data.ExtAddress64.Address.AddressLength;
               name = "ExtAddress64";
               break;
           }
           if (length <= 0)
               break;
           if (res->Data.Address.ProducerConsumer != ACPI_CONSUMER) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
                   "ignored %s %s producer\n", name,
                   acpi_address_range_name(res->Data.Address.ResourceType)));
               break;
           }
           if (res->Data.Address.ResourceType != ACPI_MEMORY_RANGE &&
               res->Data.Address.ResourceType != ACPI_IO_RANGE) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
                   "ignored %s for non-memory, non-I/O\n", name));
               break;
           }
   
   #ifdef __i386__
           if (min > ULONG_MAX || (res->Data.Address.MaxAddressFixed && max >
               ULONG_MAX)) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "ignored %s above 4G\n",
                   name));
               break;
           }
           if (max > ULONG_MAX)
                   max = ULONG_MAX;
   #endif
           if (res->Data.Address.MinAddressFixed == ACPI_ADDRESS_FIXED &&
               res->Data.Address.MaxAddressFixed == ACPI_ADDRESS_FIXED) {
               if (res->Data.Address.ResourceType == ACPI_MEMORY_RANGE) {
                   ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "%s/Memory 0x%jx/%ju\n",
                       name, (uintmax_t)min, (uintmax_t)length));
                   set->set_memory(dev, arc->context, min, length);
               } else {
                   ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "%s/IO 0x%jx/%ju\n", name,
                       (uintmax_t)min, (uintmax_t)length));
                   set->set_ioport(dev, arc->context, min, length);
               }
           } else {
               if (res->Data.Address32.ResourceType == ACPI_MEMORY_RANGE) {
                   ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
                       "%s/Memory 0x%jx-0x%jx/%ju\n", name, (uintmax_t)min,
                       (uintmax_t)max, (uintmax_t)length));
                   set->set_memoryrange(dev, arc->context, min, max, length, gran);
               } else {
                   ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "%s/IO 0x%jx-0x%jx/%ju\n",
                       name, (uintmax_t)min, (uintmax_t)max, (uintmax_t)length));
                   set->set_iorange(dev, arc->context, min, max, length, gran);
               }
           }                   
           break;
       case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
           if (res->Data.ExtendedIrq.ProducerConsumer != ACPI_CONSUMER) {
               ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "ignored ExtIRQ producer\n"));
               break;
           }
           set->set_ext_irq(dev, arc->context, res->Data.ExtendedIrq.Interrupts,
               res->Data.ExtendedIrq.InterruptCount,
               res->Data.ExtendedIrq.Triggering, res->Data.ExtendedIrq.Polarity);
           break;
       case ACPI_RESOURCE_TYPE_VENDOR:
           ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
               "unimplemented VendorSpecific resource\n"));
           break;
       default:
           break;
       }
       return (AE_OK);
   }
   
   /*
    * Fetch a device's resources and associate them with the device.
    *
    * Note that it might be nice to also locate ACPI-specific resource items, such
    * as GPE bits.
    *
    * We really need to split the resource-fetching code out from the
    * resource-parsing code, since we may want to use the parsing
    * code for _PRS someday.
    */
   ACPI_STATUS
   acpi_parse_resources(device_t dev, ACPI_HANDLE handle,
                        struct acpi_parse_resource_set *set, void *arg)
   {
       struct acpi_resource_context arc;
       ACPI_STATUS         status;
   
       ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
   
       set->set_init(dev, arg, &arc.context);
       arc.set = set;
       arc.dev = dev;
       status = AcpiWalkResources(handle, "_CRS", acpi_parse_resource, &arc);
       if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
           printf("can't fetch resources for %s - %s\n",
               acpi_name(handle), AcpiFormatException(status));
           return_ACPI_STATUS (status);
       }
       set->set_done(dev, arc.context);
       return_ACPI_STATUS (AE_OK);
   }
   
   /*
    * Resource-set vectors used to attach _CRS-derived resources 
    * to an ACPI device.
    */
   static void     acpi_res_set_init(device_t dev, void *arg, void **context);
   static void     acpi_res_set_done(device_t dev, void *context);
   static void     acpi_res_set_ioport(device_t dev, void *context,
                                       uint64_t base, uint64_t length);
   static void     acpi_res_set_iorange(device_t dev, void *context,
                                        uint64_t low, uint64_t high, 
                                        uint64_t length, uint64_t align);
   static void     acpi_res_set_memory(device_t dev, void *context,
                                       uint64_t base, uint64_t length);
   static void     acpi_res_set_memoryrange(device_t dev, void *context,
                                            uint64_t low, uint64_t high, 
                                            uint64_t length, uint64_t align);
   static void     acpi_res_set_irq(device_t dev, void *context, uint8_t *irq,
                                    int count, int trig, int pol);
   static void     acpi_res_set_ext_irq(device_t dev, void *context,
                                    uint32_t *irq, int count, int trig, int pol);
   static void     acpi_res_set_drq(device_t dev, void *context, uint8_t *drq,
                                    int count);
   static void     acpi_res_set_start_dependent(device_t dev, void *context,
                                                int preference);
   static void     acpi_res_set_end_dependent(device_t dev, void *context);
   
   struct acpi_parse_resource_set acpi_res_parse_set = {
       acpi_res_set_init,
       acpi_res_set_done,
       acpi_res_set_ioport,
       acpi_res_set_iorange,
       acpi_res_set_memory,
       acpi_res_set_memoryrange,
       acpi_res_set_irq,
       acpi_res_set_ext_irq,
       acpi_res_set_drq,
       acpi_res_set_start_dependent,
       acpi_res_set_end_dependent
   };
   
   struct acpi_res_context {
       int         ar_nio;
       int         ar_nmem;
       int         ar_nirq;
       int         ar_ndrq;
       void        *ar_parent;
   };
   
   static void
   acpi_res_set_init(device_t dev, void *arg, void **context)
   {
       struct acpi_res_context     *cp;
   
       if ((cp = AcpiOsAllocate(sizeof(*cp))) != NULL) {
           bzero(cp, sizeof(*cp));
           cp->ar_parent = arg;
           *context = cp;
       }
   }
   
   static void
   acpi_res_set_done(device_t dev, void *context)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       AcpiOsFree(cp);
   }
   
   static void
   acpi_res_set_ioport(device_t dev, void *context, uint64_t base,
                       uint64_t length)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       bus_set_resource(dev, SYS_RES_IOPORT, cp->ar_nio++, base, length);
   }
   
   static void
   acpi_res_set_iorange(device_t dev, void *context, uint64_t low,
                        uint64_t high, uint64_t length, uint64_t align)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       device_printf(dev, "I/O range not supported\n");
   }
   
   static void
   acpi_res_set_memory(device_t dev, void *context, uint64_t base,
                       uint64_t length)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
   
       bus_set_resource(dev, SYS_RES_MEMORY, cp->ar_nmem++, base, length);
   }
   
   static void
   acpi_res_set_memoryrange(device_t dev, void *context, uint64_t low,
                            uint64_t high, uint64_t length, uint64_t align)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       device_printf(dev, "memory range not supported\n");
   }
   
   static void
   acpi_res_set_irq(device_t dev, void *context, uint8_t *irq, int count,
       int trig, int pol)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL || irq == NULL)
           return;
   
       /* This implements no resource relocation. */
       if (count != 1)
           return;
   
       bus_set_resource(dev, SYS_RES_IRQ, cp->ar_nirq++, *irq, 1);
   }
   
   static void
   acpi_res_set_ext_irq(device_t dev, void *context, uint32_t *irq, int count,
       int trig, int pol)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL || irq == NULL)
           return;
   
       /* This implements no resource relocation. */
       if (count != 1)
           return;
   
       bus_set_resource(dev, SYS_RES_IRQ, cp->ar_nirq++, *irq, 1);
   }
   
   static void
   acpi_res_set_drq(device_t dev, void *context, uint8_t *drq, int count)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL || drq == NULL)
           return;
       
       /* This implements no resource relocation. */
       if (count != 1)
           return;
   
       bus_set_resource(dev, SYS_RES_DRQ, cp->ar_ndrq++, *drq, 1);
   }
   
   static void
   acpi_res_set_start_dependent(device_t dev, void *context, int preference)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       device_printf(dev, "dependent functions not supported\n");
   }
   
   static void
   acpi_res_set_end_dependent(device_t dev, void *context)
   {
       struct acpi_res_context     *cp = (struct acpi_res_context *)context;
   
       if (cp == NULL)
           return;
       device_printf(dev, "dependent functions not supported\n");
   }
   
   /*
    * Resource-owning placeholders for IO and memory pseudo-devices.
    *
    * This code allocates system resources that will be used by ACPI
    * child devices.  The acpi parent manages these resources through a
    * private rman.
    */
   
   static int      acpi_sysres_rid = 100;
   
   static int      acpi_sysres_probe(device_t dev);
   static int      acpi_sysres_attach(device_t dev);
   
   static device_method_t acpi_sysres_methods[] = {
       /* Device interface */
       DEVMETHOD(device_probe,     acpi_sysres_probe),
       DEVMETHOD(device_attach,    acpi_sysres_attach),
   
       DEVMETHOD_END
   };
   
   static driver_t acpi_sysres_driver = {
       "acpi_sysresource",
       acpi_sysres_methods,
       0,
   };
   
   static devclass_t acpi_sysres_devclass;
   DRIVER_MODULE(acpi_sysresource, acpi, acpi_sysres_driver, acpi_sysres_devclass,
       0, 0);
   MODULE_DEPEND(acpi_sysresource, acpi, 1, 1, 1);
   
   static int
   acpi_sysres_probe(device_t dev)
   {
       static char *sysres_ids[] = { "PNP0C01", "PNP0C02", NULL };
   
       if (acpi_disabled("sysresource") ||
           ACPI_ID_PROBE(device_get_parent(dev), dev, sysres_ids) == NULL)
           return (ENXIO);
   
       device_set_desc(dev, "System Resource");
       device_quiet(dev);
       return (BUS_PROBE_DEFAULT);
   }
   
   static int
   acpi_sysres_attach(device_t dev)
   {
       device_t bus;
       struct resource_list_entry *bus_rle, *dev_rle;
       struct resource_list *bus_rl, *dev_rl;
       int done, type;
       u_long start, end, count;
   
       /*
        * Loop through all current resources to see if the new one overlaps
        * any existing ones.  If so, grow the old one up and/or down
        * accordingly.  Discard any that are wholly contained in the old.  If
        * the resource is unique, add it to the parent.  It will later go into
        * the rman pool.
        */
       bus = device_get_parent(dev);
       dev_rl = BUS_GET_RESOURCE_LIST(bus, dev);
       bus_rl = BUS_GET_RESOURCE_LIST(device_get_parent(bus), bus);
       STAILQ_FOREACH(dev_rle, dev_rl, link) {
           if (dev_rle->type != SYS_RES_IOPORT && dev_rle->type != SYS_RES_MEMORY)
               continue;
   
           start = dev_rle->start;
           end = dev_rle->end;
           count = dev_rle->count;
           type = dev_rle->type;
           done = FALSE;
   
           STAILQ_FOREACH(bus_rle, bus_rl, link) {
               if (bus_rle->type != type)
                   continue;
   
               /* New resource wholly contained in old, discard. */
               if (start >= bus_rle->start && end <= bus_rle->end)
                   break;
   
               /* New tail overlaps old head, grow existing resource downward. */
               if (start < bus_rle->start && end >= bus_rle->start) {
                   bus_rle->count += bus_rle->start - start;
                   bus_rle->start = start;
                   done = TRUE;
               }
   
               /* New head overlaps old tail, grow existing resource upward. */
               if (start <= bus_rle->end && end > bus_rle->end) {
                   bus_rle->count += end - bus_rle->end;
                   bus_rle->end = end;
                   done = TRUE;
               }
   
               /* If we adjusted the old resource, we're finished. */
               if (done)
                   break;
           }
   
           /* If we didn't merge with anything, add this resource. */
           if (bus_rle == NULL)
               bus_set_resource(bus, type, acpi_sysres_rid++, start, count);
       }
   
       /* After merging/moving resources to the parent, free the list. */
       resource_list_free(dev_rl);
   
       return (0);
   }

Cache object: 7ed64f1767a98e46e593d02e61dcb134