diff options
Diffstat (limited to 'stand/i386/libi386/biosacpi.c')
| -rw-r--r-- | stand/i386/libi386/biosacpi.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/stand/i386/libi386/biosacpi.c b/stand/i386/libi386/biosacpi.c new file mode 100644 index 000000000000..8167fca7b622 --- /dev/null +++ b/stand/i386/libi386/biosacpi.c @@ -0,0 +1,144 @@ +/*- + * Copyright (c) 2001 Michael Smith <msmith@freebsd.org> + * 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("$FreeBSD$"); + +#include <stand.h> +#include <machine/stdarg.h> +#include <bootstrap.h> +#include <btxv86.h> +#include "libi386.h" + +#include "platform/acfreebsd.h" +#include "acconfig.h" +#define ACPI_SYSTEM_XFACE +#include "actypes.h" +#include "actbl.h" + +/* + * Detect ACPI and export information about the ACPI BIOS into the + * environment. + */ + +static ACPI_TABLE_RSDP *biosacpi_find_rsdp(void); +static ACPI_TABLE_RSDP *biosacpi_search_rsdp(char *base, int length); + +#define RSDP_CHECKSUM_LENGTH 20 + +void +biosacpi_detect(void) +{ + ACPI_TABLE_RSDP *rsdp; + char buf[24]; + int revision; + + /* locate and validate the RSDP */ + if ((rsdp = biosacpi_find_rsdp()) == NULL) + return; + + /* + * Report the RSDP to the kernel. While this can be found with + * a BIOS boot, the RSDP may be elsewhere when booted from UEFI. + * The old code used the 'hints' method to communite this to + * the kernel. However, while convenient, the 'hints' method + * is fragile and does not work when static hints are compiled + * into the kernel. Instead, move to setting different tunables + * that start with acpi. The old 'hints' can be removed before + * we branch for FreeBSD 12. + */ + sprintf(buf, "0x%08x", VTOP(rsdp)); + setenv("hint.acpi.0.rsdp", buf, 1); + setenv("acpi.rsdp", buf, 1); + revision = rsdp->Revision; + if (revision == 0) + revision = 1; + sprintf(buf, "%d", revision); + setenv("hint.acpi.0.revision", buf, 1); + setenv("acpi.revision", buf, 1); + strncpy(buf, rsdp->OemId, sizeof(rsdp->OemId)); + buf[sizeof(rsdp->OemId)] = '\0'; + setenv("hint.acpi.0.oem", buf, 1); + setenv("acpi.oem", buf, 1); + sprintf(buf, "0x%08x", rsdp->RsdtPhysicalAddress); + setenv("hint.acpi.0.rsdt", buf, 1); + setenv("acpi.rsdt", buf, 1); + if (revision >= 2) { + /* XXX extended checksum? */ + sprintf(buf, "0x%016llx", rsdp->XsdtPhysicalAddress); + setenv("hint.acpi.0.xsdt", buf, 1); + setenv("acpi.xsdt", buf, 1); + sprintf(buf, "%d", rsdp->Length); + setenv("hint.acpi.0.xsdt_length", buf, 1); + setenv("acpi.xsdt_length", buf, 1); + } +} + +/* + * Find the RSDP in low memory. See section 5.2.2 of the ACPI spec. + */ +static ACPI_TABLE_RSDP * +biosacpi_find_rsdp(void) +{ + ACPI_TABLE_RSDP *rsdp; + uint16_t *addr; + + /* EBDA is the 1 KB addressed by the 16 bit pointer at 0x40E. */ + addr = (uint16_t *)PTOV(0x40E); + if ((rsdp = biosacpi_search_rsdp((char *)(*addr << 4), 0x400)) != NULL) + return (rsdp); + + /* Check the upper memory BIOS space, 0xe0000 - 0xfffff. */ + if ((rsdp = biosacpi_search_rsdp((char *)0xe0000, 0x20000)) != NULL) + return (rsdp); + + return (NULL); +} + +static ACPI_TABLE_RSDP * +biosacpi_search_rsdp(char *base, int length) +{ + ACPI_TABLE_RSDP *rsdp; + u_int8_t *cp, sum; + int ofs, idx; + + /* search on 16-byte boundaries */ + for (ofs = 0; ofs < length; ofs += 16) { + rsdp = (ACPI_TABLE_RSDP *)PTOV(base + ofs); + + /* compare signature, validate checksum */ + if (!strncmp(rsdp->Signature, ACPI_SIG_RSDP, strlen(ACPI_SIG_RSDP))) { + cp = (u_int8_t *)rsdp; + sum = 0; + for (idx = 0; idx < RSDP_CHECKSUM_LENGTH; idx++) + sum += *(cp + idx); + if (sum != 0) + continue; + return(rsdp); + } + } + return(NULL); +} |