32BIT platforms only have 32bit CSR/IOCSR registers, 64BIT platforms
have both 32bit/64bit CSR/IOCSR registers. Now there are both 32bit and
64bit CSR accessors:
csr_read32()/csr_write32()/csr_xchg32();
csr_read64()/csr_write64()/csr_xchg64();
Some CSR registers (address and timer registers) are 32bit length on
32BIT platform and 64bit length on 64BIT platform. To avoid #ifdefs here
and there, they need adaptive accessors, so we define and use:
csr_read()/csr_write()/csr_xchg();
IOCSR doesn't have a "natural length", which means a 64bit register can
be treated as two 32bit registers, so we just use two 32bit accessors to
emulate a 64bit accessors.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Save and restore CSR.CNTC for hibernation which is similar to suspend.
For host this is unnecessary because sched clock is ensured continuous,
but for kvm guest sched clock isn't enough because rdtime.d should also
be continuous.
Host::rdtime.d = Host::CSR.CNTC + counter
Guest::rdtime.d = Host::CSR.CNTC + Host::CSR.GCNTC + Guest::CSR.CNTC + counter
so,
Guest::rdtime.d = Host::rdtime.d + Host::CSR.GCNTC + Guest::CSR.CNTC
To ensure Guest::rdtime.d continuous, Host::rdtime.d should be at first
continuous, while Host::CSR.GCNTC / Guest::CSR.CNTC is maintained by KVM.
Cc: stable@vger.kernel.org
Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Huacai Chen