Commit 56302c53 authored by Bogdan Purcareata's avatar Bogdan Purcareata Committed by Scott Wood

powerpc/mpic: Remove WHOAMI readback after EOI

After previous discussions regarding the subject [1][2], there's no clear
explanation or reason why the call was needed in the first place. The sensible
argument is some sort of synchronization between the CPU and the MPIC, which
hasn't been pointed out precisely and is no longer required (at least on BookE
platforms).

The benefit of this change is saving a MMIO trap per interrupt when running in a
KVM guest.

[1] https://patchwork.ozlabs.org/patch/429098/
[2] https://patchwork.ozlabs.org/patch/433557/Signed-off-by: default avatarBogdan Purcareata <bogdan.purcareata@freescale.com>
Signed-off-by: default avatarScott Wood <scottwood@freescale.com>
parent 88b7936d
...@@ -655,7 +655,6 @@ static inline struct mpic * mpic_from_irq_data(struct irq_data *d) ...@@ -655,7 +655,6 @@ static inline struct mpic * mpic_from_irq_data(struct irq_data *d)
static inline void mpic_eoi(struct mpic *mpic) static inline void mpic_eoi(struct mpic *mpic)
{ {
mpic_cpu_write(MPIC_INFO(CPU_EOI), 0); mpic_cpu_write(MPIC_INFO(CPU_EOI), 0);
(void)mpic_cpu_read(MPIC_INFO(CPU_WHOAMI));
} }
/* /*
......
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