diff options
| author | Alexey Kardashevskiy <aik@ozlabs.ru> | 2014-05-23 12:26:57 +1000 |
|---|---|---|
| committer | Alexander Graf <agraf@suse.de> | 2014-06-16 13:24:38 +0200 |
| commit | 3794d5482d74dc0031cee6d5be2c61c88ca723bd (patch) | |
| tree | 623e43c7b4391b7ca105d78143a6098096d9d7e1 /hw/ppc/spapr.c | |
| parent | 2a48d99335c572b0d3da59c1387ad131ea6ee590 (diff) | |
spapr: Implement processor compatibility in ibm, client-architecture-support
Modern Linux kernels support last POWERPC CPUs so when a kernel boots,
in most cases it can find a matching cpu_spec in the kernel's cpu_specs
list. However if the kernel is quite old, it may be missing a definition
of the actual CPU. To provide an ability for old kernels to work on modern
hardware, a Processor Compatibility Mode has been introduced
by the PowerISA specification.
>From the hardware prospective, it is supported by the Processor
Compatibility Register (PCR) which is defined in PowerISA. The register
enables one of the compatibility modes (2.05/2.06/2.07).
Since PCR is a hypervisor privileged register and cannot be
directly accessed from the guest, the mode selection is done via
ibm,client-architecture-support (CAS) RTAS call using which the guest
specifies what "raw" and "architected" CPU versions it supports.
QEMU works out the best match, changes a "cpu-version" property of
every CPU and notifies the guest about the change by setting these
properties in the buffer passed as a response on a custom H_CAS hypercall.
This implements ibm,client-architecture-support parameters parsing
(now only for PVRs) and cooks the device tree diff with new values for
"cpu-version", "ibm,ppc-interrupt-server#s" and
"ibm,ppc-interrupt-server#s" properties.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
Diffstat (limited to 'hw/ppc/spapr.c')
| -rw-r--r-- | hw/ppc/spapr.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 15adeed8e2..9756c3bded 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -34,6 +34,7 @@ #include "sysemu/kvm.h" #include "kvm_ppc.h" #include "mmu-hash64.h" +#include "qom/cpu.h" #include "hw/boards.h" #include "hw/ppc/ppc.h" @@ -588,7 +589,8 @@ int spapr_h_cas_compose_response(target_ulong addr, target_ulong size) _FDT((fdt_open_into(fdt_skel, fdt, size))); g_free(fdt_skel); - /* Place to make changes to the tree */ + /* Fix skeleton up */ + _FDT((spapr_fixup_cpu_dt(fdt, spapr))); /* Pack resulting tree */ _FDT((fdt_pack(fdt))); |