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| author | Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> | 2019-08-22 05:48:38 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-08-30 01:40:16 +0200 |
| commit | 6c85b7bc637b64e681760f62c0eafba2f56745c6 (patch) | |
| tree | 2fd6399a7d2486f07d3b2ab5939145c0b49a8d3c /arch/powerpc/include/asm/ultravisor-api.h | |
| parent | powerpc/powernv: Access LDBAR only if ultravisor disabled (diff) | |
| download | linux-6c85b7bc637b64e681760f62c0eafba2f56745c6.tar.xz linux-6c85b7bc637b64e681760f62c0eafba2f56745c6.zip | |
powerpc/kvm: Use UV_RETURN ucall to return to ultravisor
When an SVM makes an hypercall or incurs some other exception, the
Ultravisor usually forwards (a.k.a. reflects) the exceptions to the
Hypervisor. After processing the exception, Hypervisor uses the
UV_RETURN ultracall to return control back to the SVM.
The expected register state on entry to this ultracall is:
* Non-volatile registers are restored to their original values.
* If returning from an hypercall, register R0 contains the return value
(unlike other ultracalls) and, registers R4 through R12 contain any
output values of the hypercall.
* R3 contains the ultracall number, i.e UV_RETURN.
* If returning with a synthesized interrupt, R2 contains the
synthesized interrupt number.
Thanks to input from Paul Mackerras, Ram Pai and Mike Anderson.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-8-cclaudio@linux.ibm.com
Diffstat (limited to 'arch/powerpc/include/asm/ultravisor-api.h')
| -rw-r--r-- | arch/powerpc/include/asm/ultravisor-api.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/ultravisor-api.h b/arch/powerpc/include/asm/ultravisor-api.h index 8cd49abff4f3..6a0f9c74f959 100644 --- a/arch/powerpc/include/asm/ultravisor-api.h +++ b/arch/powerpc/include/asm/ultravisor-api.h @@ -24,5 +24,6 @@ /* opcodes */ #define UV_WRITE_PATE 0xF104 +#define UV_RETURN 0xF11C #endif /* _ASM_POWERPC_ULTRAVISOR_API_H */ |