2014-12-11 07:38:24

by Wenyou Yang

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

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 <[email protected]>
---
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


2014-12-16 10:20:46

by Nicolas Ferre

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

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 <[email protected]>

It seems correct to me.

Acked-by: Nicolas Ferre <[email protected]>

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

2014-12-16 19:10:43

by Florian Fainelli

[permalink] [raw]
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 écrit :
>> 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 <[email protected]>
>
> It seems correct to me.

Just one minor nit, see below

>
> Acked-by: Nicolas Ferre <[email protected]>
>
> 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);
>> }
>>
>>
>
>

2014-12-17 01:21:41

by Wenyou Yang

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

> -----Original Message-----
> From: Florian Fainelli [mailto:[email protected]]
> Sent: Wednesday, December 17, 2014 3:10 AM
> To: Ferre, Nicolas; Yang, Wenyou
> Cc: [email protected]; [email protected]; linux-
> [email protected]
> 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 écrit :
> >> 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 <[email protected]>
> >
> > It seems correct to me.
>
> Just one minor nit, see below
>
> >
> > Acked-by: Nicolas Ferre <[email protected]>
> >
> > 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

????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?