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acpi_table.c revision 1.1 
      1 /* $NetBSD: acpi_table.c,v 1.1 2018/10/12 22:15:04 jmcneill Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2018 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jared McNeill <jmcneill (at) invisible.ca>.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * ACPI table functions for use in early boot before ACPICA can be safely
     34  * initialized.
     35  */
     36 
     37 #include <sys/cdefs.h>
     38 __KERNEL_RCSID(0, "$NetBSD: acpi_table.c,v 1.1 2018/10/12 22:15:04 jmcneill Exp $");
     39 
     40 #include <sys/param.h>
     41 #include <sys/bus.h>
     42 #include <sys/cpu.h>
     43 #include <sys/device.h>
     44 
     45 #include <uvm/uvm_extern.h>
     46 
     47 #include <dev/acpi/acpireg.h>
     48 #include <dev/acpi/acpivar.h>
     49 
     50 #include <machine/acpi_machdep.h>
     51 
     52 #include <arch/arm/acpi/acpi_table.h>
     53 
     54 ACPI_STATUS
     55 acpi_table_map(ACPI_PHYSICAL_ADDRESS pa, void **hdrp)
     56 {
     57 	ACPI_TABLE_HEADER *header;
     58 	ACPI_STATUS rv;
     59 	UINT32 length;
     60 
     61 	rv = acpi_md_OsMapMemory(pa, sizeof(*header), (void **)&header);
     62 	if (ACPI_FAILURE(rv))
     63 		return rv;
     64 	length = header->Length;
     65 	acpi_md_OsUnmapMemory(header, sizeof(*header));
     66 
     67 	return acpi_md_OsMapMemory(pa, length, hdrp);
     68 }
     69 
     70 void
     71 acpi_table_unmap(ACPI_TABLE_HEADER *hdrp)
     72 {
     73 	acpi_md_OsUnmapMemory(hdrp, hdrp->Length);
     74 }
     75 
     76 ACPI_STATUS
     77 acpi_table_find(const char *sig, void **hdrp)
     78 {
     79 	ACPI_TABLE_RSDP *rsdp;
     80 	ACPI_TABLE_XSDT *xsdt;
     81 	ACPI_TABLE_HEADER *header;
     82 	ACPI_PHYSICAL_ADDRESS pa;
     83 	ACPI_STATUS rv;
     84 
     85 	/* RDSP contains a pointer to the XSDT */
     86 	pa = 0;
     87 	rv = acpi_md_OsMapMemory(acpi_md_OsGetRootPointer(), sizeof(*rsdp), (void **)&rsdp);
     88 	if (ACPI_FAILURE(rv))
     89 		return rv;
     90 	if (memcmp(rsdp->Signature, ACPI_SIG_RSDP, sizeof(rsdp->Signature)) == 0)
     91 		pa = rsdp->XsdtPhysicalAddress;
     92 	acpi_md_OsUnmapMemory(rsdp, sizeof(*rsdp));
     93 	if (pa == 0)
     94 		return AE_NOT_FOUND;
     95 
     96 	/* XSDT contains pointers to other tables */
     97 	rv = acpi_table_map(pa, (void **)&xsdt);
     98 	if (ACPI_FAILURE(rv))
     99 		return rv;
    100 	const u_int entries = (xsdt->Header.Length - sizeof(ACPI_TABLE_HEADER)) / ACPI_XSDT_ENTRY_SIZE;
    101 	for (u_int n = 0; n < entries; n++) {
    102 		rv = acpi_table_map(xsdt->TableOffsetEntry[n], (void **)&header);
    103 		if (ACPI_FAILURE(rv))
    104 			continue;
    105 		if (memcmp(header->Signature, sig, sizeof(header->Signature)) == 0) {
    106 			acpi_table_unmap((ACPI_TABLE_HEADER *)xsdt);
    107 			*hdrp = header;
    108 			return AE_OK;
    109 		}
    110 	}
    111 
    112 	/* Not found */
    113 	acpi_table_unmap((ACPI_TABLE_HEADER *)xsdt);
    114 	return AE_NOT_FOUND;
    115 }
    116