diff options
Diffstat (limited to 'sys/dev/acpica/Osd/OsdSynch.c')
| -rw-r--r-- | sys/dev/acpica/Osd/OsdSynch.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/sys/dev/acpica/Osd/OsdSynch.c b/sys/dev/acpica/Osd/OsdSynch.c new file mode 100644 index 0000000..7f38aff --- /dev/null +++ b/sys/dev/acpica/Osd/OsdSynch.c @@ -0,0 +1,131 @@ +/*- + * 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. + * + * $FreeBSD$ + */ + +/* + * 6.1 : Mutual Exclusion and Synchronisation + */ + +#include "acpi.h" + +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/mutex.h> + +MALLOC_DEFINE(M_ACPISEM, "acpisem", "ACPI semaphore"); + +/* + * Simple counting semaphore implemented using a mutex. (Subsequently used + * in the OSI code to implement a mutex. Go figure.) + */ +struct acpi_semaphore { + struct mtx as_mtx; + UINT32 as_units; + UINT32 as_maxunits; +}; + +ACPI_STATUS +AcpiOsCreateSemaphore(UINT32 MaxUnits, UINT32 InitialUnits, ACPI_HANDLE *OutHandle) +{ + struct acpi_semaphore *as; + + if (OutHandle == NULL) + return(AE_BAD_PARAMETER); + if (InitialUnits > MaxUnits) + return(AE_BAD_PARAMETER); + + if ((as = malloc(sizeof(*as), M_ACPISEM, M_NOWAIT)) == NULL) + return(AE_NO_MEMORY); + + mtx_init(&as->as_mtx, "ACPI semaphore", MTX_DEF); + as->as_units = InitialUnits; + as->as_maxunits = MaxUnits; + + *OutHandle = (ACPI_HANDLE)as; + return(AE_OK); +} + +ACPI_STATUS +AcpiOsDeleteSemaphore (ACPI_HANDLE Handle) +{ + free(Handle, M_ACPISEM); + return(AE_OK); +} + +/* + * This implementation has a bug, in that it has to stall for the entire + * timeout before it will return AE_TIME. A better implementation would + * use getmicrotime() to correctly adjust the timeout after being woken up. + */ +ACPI_STATUS +AcpiOsWaitSemaphore(ACPI_HANDLE Handle, UINT32 Units, UINT32 Timeout) +{ + struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; + int result; + + if (as == NULL) + return(AE_BAD_PARAMETER); + + mtx_enter(&as->as_mtx, MTX_DEF); + for (;;) { + if (as->as_units >= Units) { + as->as_units -= Units; + result = AE_OK; + break; + } + if (Timeout < 0) { + result = AE_TIME; + break; + } + if (msleep(as, &as->as_mtx, 0, "acpisem", Timeout / (1000 * hz)) == EWOULDBLOCK) { + result = AE_TIME; + break; + } + } + mtx_exit(&as->as_mtx, MTX_DEF); + + return(result); +} + +ACPI_STATUS +AcpiOsSignalSemaphore(ACPI_HANDLE Handle, UINT32 Units) +{ + struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; + + if (as == NULL) + return(AE_BAD_PARAMETER); + + mtx_enter(&as->as_mtx, MTX_DEF); + as->as_units += Units; + if (as->as_units > as->as_maxunits) + as->as_units = as->as_maxunits; + wakeup(as); + mtx_exit(&as->as_mtx, MTX_DEF); + + return(AE_OK); +} |
