On 01/12/15 01:51, Shannon Zhao wrote:
> Hi Marc,
>
> On 2015/12/1 1:56, Marc Zyngier wrote:
>> Same remark here as the one I made earlier. I'm pretty sure we don't
>> call any CP15 reset because they are all shared with their 64bit
>> counterparts. The same thing goes for the whole series.
> Ok, I see. But within the 64bit reset function, it needs to update the
> 32bit register value, right? Since when accessing these 32bit registers,
> it uses the offset c9_PMXXXX.
It shouldn't, because the 64bit and 32bit share the same storage. From
your own patch:
+/* Performance Monitors*/
+#define c9_PMCR (PMCR_EL0 * 2)
+#define c9_PMOVSSET (PMOVSSET_EL0 * 2)
+#define c9_PMOVSCLR (PMOVSCLR_EL0 * 2)
+#define c9_PMCCNTR (PMCCNTR_EL0 * 2)
+#define c9_PMSELR (PMSELR_EL0 * 2)
+#define c9_PMCEID0 (PMCEID0_EL0 * 2)
+#define c9_PMCEID1 (PMCEID1_EL0 * 2)
+#define c9_PMXEVCNTR (PMXEVCNTR_EL0 * 2)
+#define c9_PMXEVTYPER (PMXEVTYPER_EL0 * 2)
+#define c9_PMCNTENSET (PMCNTENSET_EL0 * 2)
+#define c9_PMCNTENCLR (PMCNTENCLR_EL0 * 2)
+#define c9_PMINTENSET (PMINTENSET_EL1 * 2)
+#define c9_PMINTENCLR (PMINTENCLR_EL1 * 2)
+#define c9_PMUSERENR (PMUSERENR_EL0 * 2)
+#define c9_PMSWINC (PMSWINC_EL0 * 2)
These are indexes in the copro array:
struct kvm_cpu_context {
struct kvm_regs gp_regs;
union {
u64 sys_regs[NR_SYS_REGS];
u32 copro[NR_COPRO_REGS];
};
};
which is in a union with the sys_reg array. So anything that affects one
affects the other because:
- there is only one state in the physical CPU, no matter which mode
you're in,
- the guest EL1 is either 32bit or 64bit, and never changes over time.
Hope this helps,
M.
--
Jazz is not dead. It just smells funny...
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