[PATCH] ARM: OMAP3+: dpll: optimize noncore dpll locking logic

From: Vikram Pandita <redacted>

If the dpll is already locked, code can be optimized
to return much earlier than doing redundent set of lock mode
and wait on idlest.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Jon Hunter <redacted>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Mike Turquette <redacted>
Cc: linux-omap at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org

Signed-off-by: Vikram Pandita <redacted>
---
 arch/arm/mach-omap2/dpll3xxx.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-omap2/dpll3xxx.c b/arch/arm/mach-omap2/dpll3xxx.c
index fc56745..3cfd7c4 100644
--- a/arch/arm/mach-omap2/dpll3xxx.c
+++ b/arch/arm/mach-omap2/dpll3xxx.c

@@ -135,11 +135,20 @@ static u16 _omap3_dpll_compute_freqsel(struct clk *clk, u8 n)
  */
 static int _omap3_noncore_dpll_lock(struct clk *clk)
 {
+	const struct dpll_data *dd;
 	u8 ai;
-	int r;
+	u8 state = 1;
+	int r = 0;
 
 	pr_debug("clock: locking DPLL %s\n", clk->name);
 
+	dd = clk->dpll_data;
+	state <<= __ffs(dd->idlest_mask);
+
+	/* Check if already locked */
+	if ((__raw_readl(dd->idlest_reg) & dd->idlest_mask) == state)
+		goto done;
+
 	ai = omap3_dpll_autoidle_read(clk);
 
 	omap3_dpll_deny_idle(clk);

@@ -151,6 +160,7 @@ static int _omap3_noncore_dpll_lock(struct clk *clk)
 	if (ai)
 		omap3_dpll_allow_idle(clk);
 
+done:
 	return r;
 }
 

-- 
1.7.9.5

Hi Nishanth

On Fri, 18 May 2012, Nishanth Menon wrote:

From: Vikram Pandita <redacted>

If the dpll is already locked, code can be optimized
to return much earlier than doing redundent set of lock mode
and wait on idlest.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Jon Hunter <redacted>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Mike Turquette <redacted>
Cc: linux-omap at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org

Signed-off-by: Vikram Pandita <redacted>

Did you intend to add your Signed-off-by: to this patch?

Also, just FYI, no need to add the Cc: lines for the mailing lists in the 
bottom of the patch description.

- Paul

- Paul

On Thu, May 24, 2012 at 2:49 AM, Paul Walmsley [off-list ref] wrote:

Hi Nishanth

On Fri, 18 May 2012, Nishanth Menon wrote:

quoted

From: Vikram Pandita <redacted>

If the dpll is already locked, code can be optimized
to return much earlier than doing redundent set of lock mode
and wait on idlest.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Jon Hunter <redacted>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Mike Turquette <redacted>
Cc: linux-omap at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org

Signed-off-by: Vikram Pandita <redacted>

Did you intend to add your Signed-off-by: to this patch?

Other than forwarding the patch over(since it seems to have slipped
through the fingers of folks monitoring the product trees), I have had
no other contributions to the patch.

Also, just FYI, no need to add the Cc: lines for the mailing lists in the
bottom of the patch description.

Thanks. point taken. will take care of that in future patches.

Regards,
Nishanth Menon

On Thu, 24 May 2012, Menon, Nishanth wrote:

On Thu, May 24, 2012 at 2:49 AM, Paul Walmsley [off-list ref] wrote:

quoted

On Fri, 18 May 2012, Nishanth Menon wrote:

quoted

From: Vikram Pandita <redacted>

If the dpll is already locked, code can be optimized
to return much earlier than doing redundent set of lock mode
and wait on idlest.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Jon Hunter <redacted>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Mike Turquette <redacted>
Cc: linux-omap at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org

Signed-off-by: Vikram Pandita <redacted>

Did you intend to add your Signed-off-by: to this patch?

Other than forwarding the patch over(since it seems to have slipped
through the fingers of folks monitoring the product trees), I have had
no other contributions to the patch.

Okay.  As I understand it, the maintainers above me would like 
Signed-off-by:s from the entire submission patch, even if there are no 
contributions to the patch itself.  So please let me know if it's okay for 
me to add your S-o-b.


- Paul

On Thu, May 24, 2012 at 9:57 AM, Paul Walmsley [off-list ref] wrote:

Okay. ?As I understand it, the maintainers above me would like
Signed-off-by:s from the entire submission patch, even if there are no
contributions to the patch itself. ?So please let me know if it's okay for
me to add your S-o-b.

Thanks. ok with me :)

Regards,
Nishanth Menon