PPC: Introduce the Virtual Time Base (VTB) SPR register
This patch adds basic support for the VTB.
PowerISA:
The Virtual Time Base (VTB) is a 64-bit incrementing counter.
Virtual Time Base increments at the same rate as the Time Base until its value
becomes 0xFFFF_FFFF_FFFF_FFFF (2 64 - 1); at the next increment its value
becomes 0x0000_0000_0000_0000. There is no interrupt or other indication when
this occurs.
The operation of the Virtual Time Base has the following additional
properties.
1. Loading a GPR from the Virtual Time Base has no effect on the accuracy of
the Virtual Time Base.
2. Copying the contents of a GPR to the Virtual Time Base replaces the
contents of the Virtual Time Base with the contents of the GPR.
Signed-off-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/target-ppc/cpu.h b/target-ppc/cpu.h
index b706b9f..abc3545 100644
--- a/target-ppc/cpu.h
+++ b/target-ppc/cpu.h
@@ -1624,6 +1624,7 @@
#define SPR_MPC_MD_DBRAM1 (0x32A)
#define SPR_RCPU_L2U_RA3 (0x32B)
#define SPR_TAR (0x32F)
+#define SPR_VTB (0x351)
#define SPR_440_INV0 (0x370)
#define SPR_440_INV1 (0x371)
#define SPR_440_INV2 (0x372)
