diff mbox

ARM: OMAP AM3517/05: hwmod data: block WFI when EMAC active

Message ID alpine.DEB.2.00.1301171919420.14118@utopia.booyaka.com (mailing list archive)
State New, archived
Headers show

Commit Message

Paul Walmsley Jan. 17, 2013, 7:21 p.m. UTC 
Hi Mark

On Tue, 8 Jan 2013, Mark A. Greer wrote:

> Sorry to nag but I think the comment needs to be updated to remove the
> sentence about the missing EMAC hwmod.

You are absolutely right, and the correction is very much appreciated.  
Updated patch follows.


- Paul

From: Paul Walmsley <paul@pwsan.com>
Date: Sun, 30 Dec 2012 10:36:36 -0700
Subject: [PATCH] ARM: OMAP AM3517/05: hwmod data: block WFI when EMAC active

According to Mark Greer, on OMAP AM3517/3505 chips, the EMAC is unable
to wake the ARM up from WFI:

    http://www.spinics.net/lists/arm-kernel/msg174734.html

Further troubleshooting was unable to narrow the problem down.  So we
don't have much choice other than to block WFI when the EMAC is active
with the HWMOD_BLOCK_WFI flag.

Based on Mark's original patch.  We're removing the omap_device-based
pm_lats code, so a different approach was needed.

This third version contains some corrections thanks to Mark's review.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Mark A. Greer <mgreer@animalcreek.com>
---
 arch/arm/mach-omap2/omap_hwmod_3xxx_data.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Mark Greer Jan. 17, 2013, 10:31 p.m. UTC | #1 
On Thu, Jan 17, 2013 at 07:21:42PM +0000, Paul Walmsley wrote:
> Hi Mark
> 
> On Tue, 8 Jan 2013, Mark A. Greer wrote:
> 
> > Sorry to nag but I think the comment needs to be updated to remove the
> > sentence about the missing EMAC hwmod.
> 
> You are absolutely right, and the correction is very much appreciated.  
> Updated patch follows.
> 
> 
> - Paul
> 
> From: Paul Walmsley <paul@pwsan.com>
> Date: Sun, 30 Dec 2012 10:36:36 -0700
> Subject: [PATCH] ARM: OMAP AM3517/05: hwmod data: block WFI when EMAC active
> 
> According to Mark Greer, on OMAP AM3517/3505 chips, the EMAC is unable
> to wake the ARM up from WFI:
> 
>     http://www.spinics.net/lists/arm-kernel/msg174734.html
> 
> Further troubleshooting was unable to narrow the problem down.  So we
> don't have much choice other than to block WFI when the EMAC is active
> with the HWMOD_BLOCK_WFI flag.
> 
> Based on Mark's original patch.  We're removing the omap_device-based
> pm_lats code, so a different approach was needed.
> 
> This third version contains some corrections thanks to Mark's review.
> 
> Signed-off-by: Paul Walmsley <paul@pwsan.com>
> Cc: Mark A. Greer <mgreer@animalcreek.com>
> ---

FWIW,

Acked-by: Mark A. Greer <mgreer@animalcreek.com>
diff mbox

Patch

diff --git a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
index 8bb2628..ac7e03e 100644
--- a/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
+++ b/arch/arm/mach-omap2/omap_hwmod_3xxx_data.c
@@ -3493,7 +3493,12 @@  static struct omap_hwmod am35xx_emac_hwmod = {
 	.name		= "davinci_emac",
 	.mpu_irqs	= am35xx_emac_mpu_irqs,
 	.class		= &am35xx_emac_class,
-	.flags		= HWMOD_NO_IDLEST,
+	/*
+	 * According to Mark Greer, the MPU will not return from WFI
+	 * when the EMAC signals an interrupt.
+	 * http://www.spinics.net/lists/arm-kernel/msg174734.html
+	 */
+	.flags		= (HWMOD_NO_IDLEST | HWMOD_BLOCK_WFI),
 };
 
 /* l3_core -> davinci emac interface */