[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH RFC 10/18] OvmfPkg/XenbusDxe: Add TestAndClearBit.
This atomically test and clear a bit. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Anthony PERARD <anthony.perard@xxxxxxxxxx> --- OvmfPkg/XenbusDxe/X64/TestAndClearBit.S | 10 ++++++++++ OvmfPkg/XenbusDxe/XenbusDxe.h | 11 +++++++++++ OvmfPkg/XenbusDxe/XenbusDxe.inf | 1 + 3 files changed, 22 insertions(+) create mode 100644 OvmfPkg/XenbusDxe/X64/TestAndClearBit.S diff --git a/OvmfPkg/XenbusDxe/X64/TestAndClearBit.S b/OvmfPkg/XenbusDxe/X64/TestAndClearBit.S new file mode 100644 index 0000000..e266f68 --- /dev/null +++ b/OvmfPkg/XenbusDxe/X64/TestAndClearBit.S @@ -0,0 +1,10 @@ +# TestAndClearBit ( +# IN INT32 Bit, // rcx +# IN volatile VOID* Address // rdx +# ); +ASM_GLOBAL ASM_PFX(TestAndClearBit) +ASM_PFX(TestAndClearBit): + lock + btrl %ecx, (%rdx) + sbbl %eax, %eax + ret diff --git a/OvmfPkg/XenbusDxe/XenbusDxe.h b/OvmfPkg/XenbusDxe/XenbusDxe.h index 975fb6b..50d0925 100644 --- a/OvmfPkg/XenbusDxe/XenbusDxe.h +++ b/OvmfPkg/XenbusDxe/XenbusDxe.h @@ -94,4 +94,15 @@ struct _XENBUS_DEVICE { shared_info_t *SharedInfo; }; +/* + * Helpers + */ + +INT32 +EFIAPI +TestAndClearBit ( + IN INT32 Bit, + IN volatile VOID *Address + ); + #endif diff --git a/OvmfPkg/XenbusDxe/XenbusDxe.inf b/OvmfPkg/XenbusDxe/XenbusDxe.inf index d4007db..dc27c13 100644 --- a/OvmfPkg/XenbusDxe/XenbusDxe.inf +++ b/OvmfPkg/XenbusDxe/XenbusDxe.inf @@ -43,6 +43,7 @@ X64/hypercall.S X64/hypercall.asm X64/InterlockedCompareExchange16.c | GCC + X64/TestAndClearBit.S [LibraryClasses] UefiDriverEntryPoint -- Anthony PERARD _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx http://lists.xen.org/xen-devel
|
Lists.xenproject.org is hosted with RackSpace, monitoring our |