Commit Graph

23 Commits

Author SHA1 Message Date
Simon Guo 173c520a04 KVM: PPC: Move nip/ctr/lr/xer registers to pt_regs in kvm_vcpu_arch
This patch moves nip/ctr/lr/xer registers from scattered places in
kvm_vcpu_arch to pt_regs structure.

cr register is "unsigned long" in pt_regs and u32 in vcpu->arch.
It will need more consideration and may move in later patches.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-05-18 15:38:23 +10:00
Bharat Bhushan 2f699a59f3 KVM: PPC: BOOKE: Emulate debug registers and exception
This patch emulates debug registers and debug exception
to support guest using debug resource. This enables running
gdb/kgdb etc in guest.

On BOOKE architecture we cannot share debug resources between QEMU and
guest because:
    When QEMU is using debug resources then debug exception must
    be always enabled. To achieve this we set MSR_DE and also set
    MSRP_DEP so guest cannot change MSR_DE.

    When emulating debug resource for guest we want guest
    to control MSR_DE (enable/disable debug interrupt on need).

    So above mentioned two configuration cannot be supported
    at the same time. So the result is that we cannot share
    debug resources between QEMU and Guest on BOOKE architecture.

In the current design QEMU gets priority over guest, this means that if
QEMU is using debug resources then guest cannot use them and if guest is
using debug resource then QEMU can overwrite them.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:33 +02:00
Bharat Bhushan 348ba71081 KVM: PPC: BOOKE: Guest and hardware visible debug registers are same
Guest visible debug register and hardware visible debug registers are
same, so ther is no need to have arch->shadow_dbg_reg, instead use
arch->dbg_reg.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:30 +02:00
Bharat Bhushan c8ca97ca9b KVM: PPC: BOOKE : Emulate rfdi instruction
This patch adds "rfdi" instruction emulation which is required for
guest debug hander on BOOKE-HV

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-09-22 10:11:29 +02:00
Bharat Bhushan c1b8a01bf9 kvm: ppc: booke: Use the shared struct helpers for SPRN_SPRG0-7
Use kvmppc_set_sprg[0-7]() and kvmppc_get_sprg[0-7]() helper
functions

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28 15:23:12 +02:00
Alexander Graf 37ecb257f6 KVM: PPC: BookE: Emulate mfspr on EPR
The EPR register is potentially valid for PR KVM as well, so we need
to emulate accesses to it. It's only defined for reading, so only
handle the mfspr case.

Signed-off-by: Alexander Graf <agraf@suse.de>
2013-01-10 13:42:30 +01:00
Mihai Caraman 38f988240c KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation
Add EPCR support in booke mtspr/mfspr emulation. EPCR register is defined only
for 64-bit and HV categories, we will expose it at this point only to 64-bit
virtual processors running on 64-bit HV hosts.
Define a reusable setter function for vcpu's EPCR.

Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com>
[agraf: move HV dependency in the code]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-12-06 01:34:19 +01:00
Alexander Graf 50c871edf5 KVM: PPC: BookE: Add MCSR SPR support
Add support for the MCSR SPR. This only implements the SPR storage
bits, not actual machine checks.

Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:48 +02:00
Bharat Bhushan 6df8d3fc58 booke: Added ONE_REG interface for IAC/DAC debug registers
IAC/DAC are defined as 32 bit while they are 64 bit wide. So ONE_REG
interface is added to set/get them.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:47 +02:00
Bharat Bhushan f61c94bb99 KVM: PPC: booke: Add watchdog emulation
This patch adds the watchdog emulation in KVM. The watchdog
emulation is enabled by KVM_ENABLE_CAP(KVM_CAP_PPC_BOOKE_WATCHDOG) ioctl.
The kernel timer are used for watchdog emulation and emulates
h/w watchdog state machine. On watchdog timer expiry, it exit to QEMU
if TCR.WRC is non ZERO. QEMU can reset/shutdown etc depending upon how
it is configured.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
[bharat.bhushan@freescale.com: reworked patch]
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
[agraf: adjust to new request framework]
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-10-05 23:38:47 +02:00
Bharat Bhushan 0c1fc3c3c4 KVM: PPC: Critical interrupt emulation support
rfci instruction and CSRR0/1 registers are emulated.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-07-11 17:39:38 +02:00
Bharat Bhushan 21bd000abf KVM: PPC: booke: Added DECAR support
Added the decrementer auto-reload support. DECAR is readable
on e500v2/e500mc and later cpus.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-30 11:43:11 +02:00
Alexander Graf 54771e6217 KVM: PPC: Emulator: clean up SPR reads and writes
When reading and writing SPRs, every SPR emulation piece had to read
or write the respective GPR the value was read from or stored in itself.

This approach is pretty prone to failure. What if we accidentally
implement mfspr emulation where we just do "break" and nothing else?
Suddenly we would get a random value in the return register - which is
always a bad idea.

So let's consolidate the generic code paths and only give the core
specific SPR handling code readily made variables to read/write from/to.

Functionally, this patch doesn't change anything, but it increases the
readability of the code and makes is less prone to bugs.

Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06 16:19:13 +02:00
Alexander Graf c46dc9a861 KVM: PPC: Emulator: clean up instruction parsing
Instructions on PPC are pretty similarly encoded. So instead of
every instruction emulation code decoding the instruction fields
itself, we can move that code to more generic places and rely on
the compiler to optimize the unused bits away.

This has 2 advantages. It makes the code smaller and it makes the
code less error prone, as the instruction fields are always
available, so accidental misusage is reduced.

Functionally, this patch doesn't change anything.

Signed-off-by: Alexander Graf <agraf@suse.de>
2012-05-06 16:19:12 +02:00
Scott Wood d30f6e4800 KVM: PPC: booke: category E.HV (GS-mode) support
Chips such as e500mc that implement category E.HV in Power ISA 2.06
provide hardware virtualization features, including a new MSR mode for
guest state.  The guest OS can perform many operations without trapping
into the hypervisor, including transitions to and from guest userspace.

Since we can use SRR1[GS] to reliably tell whether an exception came from
guest state, instead of messing around with IVPR, we use DO_KVM similarly
to book3s.

Current issues include:
 - Machine checks from guest state are not routed to the host handler.
 - The guest can cause a host oops by executing an emulated instruction
   in a page that lacks read permission.  Existing e500/4xx support has
   the same problem.

Includes work by Ashish Kalra <Ashish.Kalra@freescale.com>,
Varun Sethi <Varun.Sethi@freescale.com>, and
Liu Yu <yu.liu@freescale.com>.

Signed-off-by: Scott Wood <scottwood@freescale.com>
[agraf: remove pt_regs usage]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:51:19 +03:00
Scott Wood dfd4d47e9a KVM: PPC: booke: Improve timer register emulation
Decrementers are now properly driven by TCR/TSR, and the guest
has full read/write access to these registers.

The decrementer keeps ticking (and setting the TSR bit) regardless of
whether the interrupts are enabled with TCR.

The decrementer stops at zero, rather than going negative.

Decrementers (and FITs, once implemented) are delivered as
level-triggered interrupts -- dequeued when the TSR bit is cleared, not
on delivery.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
[scottwood@freescale.com: significant changes]
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:27 +02:00
Scott Wood b59049720d KVM: PPC: Paravirtualize SPRG4-7, ESR, PIR, MASn
This allows additional registers to be accessed by the guest
in PR-mode KVM without trapping.

SPRG4-7 are readable from userspace.  On booke, KVM will sync
these registers when it enters the guest, so that accesses from
guest userspace will work.  The guest kernel, OTOH, must consistently
use either the real registers or the shared area between exits.  This
also applies to the already-paravirted SPRG3.

On non-booke, it's not clear to what extent SPRG4-7 are supported
(they're not architected for book3s, but exist on at least some classic
chips).  They are copied in the get/set regs ioctls, but I do not see any
non-booke emulation.  I also do not see any syncing with real registers
(in PR-mode) including the user-readable SPRG3.  This patch should not
make that situation any worse.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:26 +02:00
Alexander Graf de7906c36c KVM: PPC: Convert SRR0 and SRR1 to shared page
The SRR0 and SRR1 registers contain cached values of the PC and MSR
respectively. They get written to by the hypervisor when an interrupt
occurs or directly by the kernel. They are also used to tell the rfi(d)
instruction where to jump to.

Because it only gets touched on defined events that, it's very simple to
share with the guest. Hypervisor and guest both have full r/w access.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf 5e030186df KVM: PPC: Convert DAR to shared page.
The DAR register contains the address a data page fault occured at. This
register behaves pretty much like a simple data storage register that gets
written to on data faults. There is no hypervisor interaction required on
read or write.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:45 +02:00
Alexander Graf 666e7252a1 KVM: PPC: Convert MSR to shared page
One of the most obvious registers to share with the guest directly is the
MSR. The MSR contains the "interrupts enabled" flag which the guest has to
toggle in critical sections.

So in order to bring the overhead of interrupt en- and disabling down, let's
put msr into the shared page. Keep in mind that even though you can fully read
its contents, writing to it doesn't always update all state. There are a few
safe fields that don't require hypervisor interaction. See the documentation
for a list of MSR bits that are safe to be set from inside the guest.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:43 +02:00
Alexander Graf 8e5b26b55a KVM: PPC: Use accessor functions for GPR access
All code in PPC KVM currently accesses gprs in the vcpu struct directly.

While there's nothing wrong with that wrt the current way gprs are stored
and loaded, it doesn't suffice for the PACA acceleration that will follow
in this patchset.

So let's just create little wrapper inline functions that we call whenever
a GPR needs to be read from or written to. The compiled code shouldn't really
change at all for now.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:35:47 -03:00
Hollis Blanchard f7b200af8f KVM: ppc: Add dbsr in kvm_vcpu_arch
Kernel for E500 need clear dbsr when startup.
So add dbsr register in kvm_vcpu_arch for BOOKE.

Signed-off-by: Liu Yu <yu.liu@freescale.com>
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:57 +02:00
Hollis Blanchard d0c7dc0344 KVM: ppc: split out common Book E instruction emulation
The Book E code will be shared with e500.

I've left PID in kvmppc_core_emulate_op() just so that we don't need to move
kvmppc_set_pid() right now. Once we have the e500 implementation, we can
probably share that too.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:57 +02:00