[PATCH 1/2] ARM: OMAP3: PM: remove superfluous calls to pwrdm_clear_all_prev_pwrst()

Shilimkar, Santosh santosh.shilimkar at ti.com
Mon Jan 30 05:54:28 EST 2012


On Mon, Jan 30, 2012 at 3:13 PM, Paul Walmsley <paul at pwsan.com> wrote:
> Remove some superfluous calls to pwrdm_clear_all_prev_pwrst().
> pwrdm_pre_transition(), which appears a few lines after these calls,
> invokes pwrdm_clear_all_prev_pwrst() on each powerdomain -- there's no
> need to do it twice.
>
> N.B.: some of us have observed that accesses to the previous
> powerstate registers seem to be quite slow.  Although the writes
> removed by this patch should be buffered by the write buffer, there is
> a read to a PRM register immediately afterwards.  That will block the
> OMAP3 MPU until all of those writes complete.  So this patch should
> result in a minor performance improvement during idle entry.
>
> Signed-off-by: Paul Walmsley <paul at pwsan.com>
> Cc: Kevin Hilman <khilman at ti.com>
> Cc: Rajendra Nayak <rnayak at ti.com>
> Cc: Santosh Shilimkar <santosh.shilimkar at ti.com>
> Cc: Tero Kristo <t-kristo at ti.com>
> ---
Nice clean-up
Acked-by: Santosh Shilimkar <santosh.shilimkar at ti.com>



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