[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[Wenyou Yang]

Appearance: On some SAMA5D4EK boards, after power up, the Eth1 doesn't work.

Reason: The PIOE2 pin is connected to the NAND_Tree# of KSZ8081,
But it outputs LOW during the reset period, which cause the NAND_Tree# enabled.

Add phy_fixup() to disable NAND_Tree by overriding the Operation
Mode Strap Override register(i.e. Register 16h) to clear the NAND_Tree bit.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
---
 arch/arm/mach-at91/board-dt-sama5.c |   18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/arch/arm/mach-at91/board-dt-sama5.c b/arch/arm/mach-at91/board-dt-sama5.c
index 8fb9ef5..97f7367 100644
--- a/arch/arm/mach-at91/board-dt-sama5.c
+++ b/arch/arm/mach-at91/board-dt-sama5.c
@@ -17,6 +17,7 @@
 #include <linux/of_platform.h>
 #include <linux/phy.h>
 #include <linux/clk-provider.h>
+#include <linux/phy.h>
 
 #include <asm/setup.h>
 #include <asm/irq.h>
@@ -26,8 +27,25 @@
 
 #include "generic.h"
 
+static int ksz8081_phy_fixup(struct phy_device *phy)
+{
+	int value;
+
+	value = phy_read(phy, 0x16);
+	value &= ~0x20;
+	phy_write(phy, 0x16, value);
+
+	return 0;
+}
+
 static void __init sama5_dt_device_init(void)
 {
+	if (of_machine_is_compatible("atmel,sama5d4ek") &&
+	   IS_ENABLED(CONFIG_PHYLIB)) {
+		phy_register_fixup_for_id("fc028000.etherne:00",
+						ksz8081_phy_fixup);
+	}
+
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 }
 
-- 
1.7.9.5

[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[Nicolas Ferre]

Le 11/12/2014 08:31, Wenyou Yang a ?crit :
> Appearance: On some SAMA5D4EK boards, after power up, the Eth1 doesn't work.
> 
> Reason: The PIOE2 pin is connected to the NAND_Tree# of KSZ8081,
> But it outputs LOW during the reset period, which cause the NAND_Tree# enabled.
> 
> Add phy_fixup() to disable NAND_Tree by overriding the Operation
> Mode Strap Override register(i.e. Register 16h) to clear the NAND_Tree bit.
> 
> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>

It seems correct to me.

Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Anyway, I add Florian in the loop as he is the one who proposed this
solution. So it would have been good to have his feeling about the
implementation...

Bye,

> ---
>  arch/arm/mach-at91/board-dt-sama5.c |   18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/arch/arm/mach-at91/board-dt-sama5.c b/arch/arm/mach-at91/board-dt-sama5.c
> index 8fb9ef5..97f7367 100644
> --- a/arch/arm/mach-at91/board-dt-sama5.c
> +++ b/arch/arm/mach-at91/board-dt-sama5.c
> @@ -17,6 +17,7 @@
>  #include <linux/of_platform.h>
>  #include <linux/phy.h>
>  #include <linux/clk-provider.h>
> +#include <linux/phy.h>
>  
>  #include <asm/setup.h>
>  #include <asm/irq.h>
> @@ -26,8 +27,25 @@
>  
>  #include "generic.h"
>  
> +static int ksz8081_phy_fixup(struct phy_device *phy)
> +{
> +	int value;
> +
> +	value = phy_read(phy, 0x16);
> +	value &= ~0x20;
> +	phy_write(phy, 0x16, value);
> +
> +	return 0;
> +}
> +
>  static void __init sama5_dt_device_init(void)
>  {
> +	if (of_machine_is_compatible("atmel,sama5d4ek") &&
> +	   IS_ENABLED(CONFIG_PHYLIB)) {
> +		phy_register_fixup_for_id("fc028000.etherne:00",
> +						ksz8081_phy_fixup);
> +	}
> +
>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
>  }
>  
> 


-- 
Nicolas Ferre

[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[Florian Fainelli]

On 16/12/14 02:20, Nicolas Ferre wrote:
> Le 11/12/2014 08:31, Wenyou Yang a ?crit :
>> Appearance: On some SAMA5D4EK boards, after power up, the Eth1 doesn't work.
>>
>> Reason: The PIOE2 pin is connected to the NAND_Tree# of KSZ8081,
>> But it outputs LOW during the reset period, which cause the NAND_Tree# enabled.
>>
>> Add phy_fixup() to disable NAND_Tree by overriding the Operation
>> Mode Strap Override register(i.e. Register 16h) to clear the NAND_Tree bit.
>>
>> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> 
> It seems correct to me.

Just one minor nit, see below

> 
> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
> 
> Anyway, I add Florian in the loop as he is the one who proposed this
> solution. So it would have been good to have his feeling about the
> implementation...
> 
> Bye,
> 
>> ---
>>  arch/arm/mach-at91/board-dt-sama5.c |   18 ++++++++++++++++++
>>  1 file changed, 18 insertions(+)
>>
>> diff --git a/arch/arm/mach-at91/board-dt-sama5.c b/arch/arm/mach-at91/board-dt-sama5.c
>> index 8fb9ef5..97f7367 100644
>> --- a/arch/arm/mach-at91/board-dt-sama5.c
>> +++ b/arch/arm/mach-at91/board-dt-sama5.c
>> @@ -17,6 +17,7 @@
>>  #include <linux/of_platform.h>
>>  #include <linux/phy.h>
>>  #include <linux/clk-provider.h>
>> +#include <linux/phy.h>
>>  
>>  #include <asm/setup.h>
>>  #include <asm/irq.h>
>> @@ -26,8 +27,25 @@
>>  
>>  #include "generic.h"
>>  
>> +static int ksz8081_phy_fixup(struct phy_device *phy)
>> +{
>> +	int value;
>> +
>> +	value = phy_read(phy, 0x16);
>> +	value &= ~0x20;
>> +	phy_write(phy, 0x16, value);
>> +
>> +	return 0;
>> +}
>> +
>>  static void __init sama5_dt_device_init(void)
>>  {
>> +	if (of_machine_is_compatible("atmel,sama5d4ek") &&
>> +	   IS_ENABLED(CONFIG_PHYLIB)) {
>> +		phy_register_fixup_for_id("fc028000.etherne:00",
>> +						ksz8081_phy_fixup);

Matching the bus id certainly works, but I would rather match on your
specific PHY device 32-bits OUI to make sure that if you ever change the
PHY on a different design, this is not inadvertently writing to a
register that is not micrel specific?

>> +	}
>> +
>>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
>>  }
>>  
>>
> 
> 

[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[Yang, Wenyou]

> -----Original Message-----
> From: Florian Fainelli [mailto:f.fainelli at gmail.com]
> Sent: Wednesday, December 17, 2014 3:10 AM
> To: Ferre, Nicolas; Yang, Wenyou
> Cc: linux at arm.linux.org.uk; linux-arm-kernel at lists.infradead.org; linux-
> kernel at vger.kernel.org
> Subject: Re: [PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override
> NAND_Tree which improperly strapp-in during the reset period.
> 
> On 16/12/14 02:20, Nicolas Ferre wrote:
> > Le 11/12/2014 08:31, Wenyou Yang a ?crit :
> >> Appearance: On some SAMA5D4EK boards, after power up, the Eth1 doesn't
> work.
> >>
> >> Reason: The PIOE2 pin is connected to the NAND_Tree# of KSZ8081, But
> >> it outputs LOW during the reset period, which cause the NAND_Tree# enabled.
> >>
> >> Add phy_fixup() to disable NAND_Tree by overriding the Operation Mode
> >> Strap Override register(i.e. Register 16h) to clear the NAND_Tree bit.
> >>
> >> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> >
> > It seems correct to me.
> 
> Just one minor nit, see below
> 
> >
> > Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
> >
> > Anyway, I add Florian in the loop as he is the one who proposed this
> > solution. So it would have been good to have his feeling about the
> > implementation...
> >
> > Bye,
> >
> >> ---
> >>  arch/arm/mach-at91/board-dt-sama5.c |   18 ++++++++++++++++++
> >>  1 file changed, 18 insertions(+)
> >>
> >> diff --git a/arch/arm/mach-at91/board-dt-sama5.c
> >> b/arch/arm/mach-at91/board-dt-sama5.c
> >> index 8fb9ef5..97f7367 100644
> >> --- a/arch/arm/mach-at91/board-dt-sama5.c
> >> +++ b/arch/arm/mach-at91/board-dt-sama5.c
> >> @@ -17,6 +17,7 @@
> >>  #include <linux/of_platform.h>
> >>  #include <linux/phy.h>
> >>  #include <linux/clk-provider.h>
> >> +#include <linux/phy.h>
> >>
> >>  #include <asm/setup.h>
> >>  #include <asm/irq.h>
> >> @@ -26,8 +27,25 @@
> >>
> >>  #include "generic.h"
> >>
> >> +static int ksz8081_phy_fixup(struct phy_device *phy) {
> >> +	int value;
> >> +
> >> +	value = phy_read(phy, 0x16);
> >> +	value &= ~0x20;
> >> +	phy_write(phy, 0x16, value);
> >> +
> >> +	return 0;
> >> +}
> >> +
> >>  static void __init sama5_dt_device_init(void)  {
> >> +	if (of_machine_is_compatible("atmel,sama5d4ek") &&
> >> +	   IS_ENABLED(CONFIG_PHYLIB)) {
> >> +		phy_register_fixup_for_id("fc028000.etherne:00",
> >> +						ksz8081_phy_fixup);
> 
> Matching the bus id certainly works, but I would rather match on your specific PHY
> device 32-bits OUI to make sure that if you ever change the PHY on a different
> design, this is not inadvertently writing to a register that is not micrel specific?
I don't think so.
Under the board compatible limitation, matching the bus id is enough for this case reason described above.

Moreover the PHY OUI is default value on the sama5d4ek.
MII_PHYSID1.15:0:  0x0022
MII_PHYSID2.15:10: 000101b

> 
> >> +	}
> >> +
> >>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
> >> }
> >>
> >>
> >
> >

Best Regards,
Wenyou Yang

[PATCH] ARM: at91: board-dt-sama5: add phy_fixup to override NAND_Tree which improperly strapp-in during the reset period.

[Nicolas Ferre]

Le 11/12/2014 08:31, Wenyou Yang a ?crit :
> Appearance: On some SAMA5D4EK boards, after power up, the Eth1 doesn't work.
> 
> Reason: The PIOE2 pin is connected to the NAND_Tree# of KSZ8081,
> But it outputs LOW during the reset period, which cause the NAND_Tree# enabled.
> 
> Add phy_fixup() to disable NAND_Tree by overriding the Operation
> Mode Strap Override register(i.e. Register 16h) to clear the NAND_Tree bit.
> 
> Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>

Stacked on top of at91-3.19-fixes.

Bye,


> ---
>  arch/arm/mach-at91/board-dt-sama5.c |   18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/arch/arm/mach-at91/board-dt-sama5.c b/arch/arm/mach-at91/board-dt-sama5.c
> index 8fb9ef5..97f7367 100644
> --- a/arch/arm/mach-at91/board-dt-sama5.c
> +++ b/arch/arm/mach-at91/board-dt-sama5.c
> @@ -17,6 +17,7 @@
>  #include <linux/of_platform.h>
>  #include <linux/phy.h>
>  #include <linux/clk-provider.h>
> +#include <linux/phy.h>
>  
>  #include <asm/setup.h>
>  #include <asm/irq.h>
> @@ -26,8 +27,25 @@
>  
>  #include "generic.h"
>  
> +static int ksz8081_phy_fixup(struct phy_device *phy)
> +{
> +	int value;
> +
> +	value = phy_read(phy, 0x16);
> +	value &= ~0x20;
> +	phy_write(phy, 0x16, value);
> +
> +	return 0;
> +}
> +
>  static void __init sama5_dt_device_init(void)
>  {
> +	if (of_machine_is_compatible("atmel,sama5d4ek") &&
> +	   IS_ENABLED(CONFIG_PHYLIB)) {
> +		phy_register_fixup_for_id("fc028000.etherne:00",
> +						ksz8081_phy_fixup);
> +	}
> +
>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
>  }
>  
> 


-- 
Nicolas Ferre