motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-07 09:43:56 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

target/ppc: Add clrbhrb and mfbhrbe instructions

Browse source 
Add support for the clrbhrb and mfbhrbe instructions.

Since neither instruction is believed to be critical to
performance, both instructions were implemented using helper
functions.

Access to both instructions is controlled by bits in the
HFSCR (for privileged state) and MMCR0 (for problem state).
A new function, helper_mmcr0_facility_check, was added for
checking MMCR0[BHRBA] and raising a facility_unavailable exception
if required.

NOTE: For P8 and P9, due to a performance issue, branch history will
not be kept, but the instructions will be allowed to execute
as normal with the exception that the mfbhrbe instruction will
always return a zero value.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Glenn Miles <milesg@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
This commit is contained in:
Glenn Miles 2024-03-28 20:41:35 +10:00 • committed by Nicholas Piggin
parent 4de4a4705f
commit 6bfcf1dc23
6 changed files with 112 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

2
target/ppc/cpu.h
View file

@ -535,6 +535,7 @@ FIELD(MSR, LE, MSR_LE, 1)
#define MMCR0_PMCjCE PPC_BIT(49) /* MMCR0 PMCj Condition Enabled */
#define MMCR0_FCP PPC_BIT(34) /* Freeze Counters/BHRB if PR=1 */
#define MMCR0_FCPC PPC_BIT(51) /* Condition for FCP bit */
#define MMCR0_BHRBA_NR PPC_BIT_NR(42) /* BHRB Available */
/* MMCR0 userspace r/w mask */
#define MMCR0_UREG_MASK (MMCR0_FC | MMCR0_PMAO | MMCR0_PMAE)
/* MMCR2 userspace r/w mask */
@ -634,6 +635,7 @@ FIELD(MSR, LE, MSR_LE, 1)
/* HFSCR bits */
#define HFSCR_MSGP PPC_BIT(53) /* Privileged Message Send Facilities */
#define HFSCR_BHRB PPC_BIT(59) /* BHRB Instructions */
#define HFSCR_IC_MSGP 0xA
#define DBCR0_ICMP (1 << 27)