[PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Ard Biesheuvel]

The SATA spec mandates that link detection by the PHY completes within
10 ms after receiving a reset signal. However, there is no obligation
to uphold this requirement at the driver end as strictly as we do, and
as it turns out, some combinations of host and device (e.g., Samsung
850 EVO connected to a LeMaker Cello) are only borderline compliant,
which means the device is not detected reliably.

So let's allow for a bit of margin, and increase the PHY detect timeout
value to 15 ms.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
v2: update comment in AhciModeInitialization() as well

 MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++--
 MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
index 4d01c1dd7fca..4418e5c3763e 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
@@ -2376,8 +2376,9 @@ AhciModeInitialization (
       AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
 
       //
-      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
-      // It's the requirment from SATA1.0a spec section 5.2.
+      // Wait at least 10 ms for the Phy to detect the presence of a device.
+      // It's the requirement from SATA1.0a spec section 5.2.
+      // Add a bit of margin for robustness.
       //
       PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
       Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH + EFI_AHCI_PORT_SSTS;
diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
index 6401fb2e9fcd..809bcc307fc4 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
@@ -41,8 +41,9 @@ typedef union {
 
 //
 // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
+// Add a bit of margin for robustness.
 //
-#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
+#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
 //
 // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
 //
-- 
2.9.3

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Zeng, Star]

The updated comments "Wait at least 10 ms" seems not correct.


Thanks,
Star
-----Original Message-----
From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ard Biesheuvel
Sent: Wednesday, June 28, 2017 4:23 PM
To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

The SATA spec mandates that link detection by the PHY completes within
10 ms after receiving a reset signal. However, there is no obligation to uphold this requirement at the driver end as strictly as we do, and as it turns out, some combinations of host and device (e.g., Samsung
850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.

So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
v2: update comment in AhciModeInitialization() as well

 MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++--  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
index 4d01c1dd7fca..4418e5c3763e 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
@@ -2376,8 +2376,9 @@ AhciModeInitialization (
       AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
 
       //
-      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
-      // It's the requirment from SATA1.0a spec section 5.2.
+      // Wait at least 10 ms for the Phy to detect the presence of a device.
+      // It's the requirement from SATA1.0a spec section 5.2.
+      // Add a bit of margin for robustness.
       //
       PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
       Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH + EFI_AHCI_PORT_SSTS; diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
index 6401fb2e9fcd..809bcc307fc4 100644
--- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
+++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
@@ -41,8 +41,9 @@ typedef union {
 
 //
 // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
+// Add a bit of margin for robustness.
 //
-#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
+#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
 //
 // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
 //
--
2.9.3

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edk2-devel@lists.01.org
https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Ard Biesheuvel]

On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
> The updated comments "Wait at least 10 ms" seems not correct.
>

That is the whole point of the change. The SATA spec mandates that the
PHY respond within 10 ms. It does *not* mandate that the software wait
10 ms or less, rather the opposite, i.e., that the software should
wait 10 ms or *more*, so 'at least 10ms'. The original comment said
that the software *must* wait for no more than 10 ms, but this is not
what the spec says.



> -----Original Message-----
> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ard Biesheuvel
> Sent: Wednesday, June 28, 2017 4:23 PM
> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout
>
> The SATA spec mandates that link detection by the PHY completes within
> 10 ms after receiving a reset signal. However, there is no obligation to uphold this requirement at the driver end as strictly as we do, and as it turns out, some combinations of host and device (e.g., Samsung
> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>
> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> ---
> v2: update comment in AhciModeInitialization() as well
>
>  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++--  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>  2 files changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
> index 4d01c1dd7fca..4418e5c3763e 100644
> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>        AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>
>        //
> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
> -      // It's the requirment from SATA1.0a spec section 5.2.
> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
> +      // It's the requirement from SATA1.0a spec section 5.2.
> +      // Add a bit of margin for robustness.
>        //
>        PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>        Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH + EFI_AHCI_PORT_SSTS; diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
> index 6401fb2e9fcd..809bcc307fc4 100644
> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
> @@ -41,8 +41,9 @@ typedef union {
>
>  //
>  // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
> +// Add a bit of margin for robustness.
>  //
> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>  //
>  // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>  //
> --
> 2.9.3
>
> _______________________________________________
> edk2-devel mailing list
> edk2-devel@lists.01.org
> https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Ard Biesheuvel]

On 28 June 2017 at 08:49, Tian, Feng <feng.tian@intel.com> wrote:
> Ard & Star,
>
> I agree this patch to solve device compatible issue as it has no side effect for normal case.
>
> Just a minor correction:
> SATA 2.5 spec says: "If a device is present, the Phy shall take no longer than 10 ms to indicate that it has detected the presence of a device". That's why the original code think it *MUST* be less than 10ms.
>

Yes, I see where the confusion comes from. But the SATA spec primarily
describes the requirements for the hardware side, which are the
opposite of those for the software side.

Thanks,
Ard.


> -----Original Message-----
> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> Sent: Wednesday, June 28, 2017 4:43 PM
> To: Zeng, Star <star.zeng@intel.com>
> Cc: edk2-devel@lists.01.org; Tian, Feng <feng.tian@intel.com>; Dong, Eric <eric.dong@intel.com>; leif.lindholm@linaro.org
> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout
>
> On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
>> The updated comments "Wait at least 10 ms" seems not correct.
>>
>
> That is the whole point of the change. The SATA spec mandates that the PHY respond within 10 ms. It does *not* mandate that the software wait
> 10 ms or less, rather the opposite, i.e., that the software should wait 10 ms or *more*, so 'at least 10ms'. The original comment said that the software *must* wait for no more than 10 ms, but this is not what the spec says.
>
>
>
>> -----Original Message-----
>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of
>> Ard Biesheuvel
>> Sent: Wednesday, June 28, 2017 4:23 PM
>> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
>> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric
>> <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel
>> <ard.biesheuvel@linaro.org>
>> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY
>> detect timeout
>>
>> The SATA spec mandates that link detection by the PHY completes within
>> 10 ms after receiving a reset signal. However, there is no obligation
>> to uphold this requirement at the driver end as strictly as we do, and
>> as it turns out, some combinations of host and device (e.g., Samsung
>> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>>
>> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>>
>> Contributed-under: TianoCore Contribution Agreement 1.0
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> ---
>> v2: update comment in AhciModeInitialization() as well
>>
>>  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++--
>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>>  2 files changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> index 4d01c1dd7fca..4418e5c3763e 100644
>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>>        AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>>
>>        //
>> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
>> -      // It's the requirment from SATA1.0a spec section 5.2.
>> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
>> +      // It's the requirement from SATA1.0a spec section 5.2.
>> +      // Add a bit of margin for robustness.
>>        //
>>        PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>>        Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH +
>> EFI_AHCI_PORT_SSTS; diff --git
>> a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> index 6401fb2e9fcd..809bcc307fc4 100644
>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> @@ -41,8 +41,9 @@ typedef union {
>>
>>  //
>>  // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
>> +// Add a bit of margin for robustness.
>>  //
>> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
>> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>>  //
>>  // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>>  //
>> --
>> 2.9.3
>>
>> _______________________________________________
>> edk2-devel mailing list
>> edk2-devel@lists.01.org
>> https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Zeng, Star]

The real delay may be 0ms if the DET register value just pass the check after the first AhciReadReg().
But what does "Wait at least 10 ms" mean?


Thanks,
Star
-----Original Message-----
From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ard Biesheuvel
Sent: Wednesday, June 28, 2017 4:58 PM
To: Tian, Feng <feng.tian@intel.com>
Cc: leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric <eric.dong@intel.com>; Zeng, Star <star.zeng@intel.com>
Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

On 28 June 2017 at 08:49, Tian, Feng <feng.tian@intel.com> wrote:
> Ard & Star,
>
> I agree this patch to solve device compatible issue as it has no side effect for normal case.
>
> Just a minor correction:
> SATA 2.5 spec says: "If a device is present, the Phy shall take no longer than 10 ms to indicate that it has detected the presence of a device". That's why the original code think it *MUST* be less than 10ms.
>

Yes, I see where the confusion comes from. But the SATA spec primarily describes the requirements for the hardware side, which are the opposite of those for the software side.

Thanks,
Ard.


> -----Original Message-----
> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> Sent: Wednesday, June 28, 2017 4:43 PM
> To: Zeng, Star <star.zeng@intel.com>
> Cc: edk2-devel@lists.01.org; Tian, Feng <feng.tian@intel.com>; Dong, 
> Eric <eric.dong@intel.com>; leif.lindholm@linaro.org
> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax 
> PHY detect timeout
>
> On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
>> The updated comments "Wait at least 10 ms" seems not correct.
>>
>
> That is the whole point of the change. The SATA spec mandates that the 
> PHY respond within 10 ms. It does *not* mandate that the software wait
> 10 ms or less, rather the opposite, i.e., that the software should wait 10 ms or *more*, so 'at least 10ms'. The original comment said that the software *must* wait for no more than 10 ms, but this is not what the spec says.
>
>
>
>> -----Original Message-----
>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf 
>> Of Ard Biesheuvel
>> Sent: Wednesday, June 28, 2017 4:23 PM
>> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
>> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric 
>> <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel 
>> <ard.biesheuvel@linaro.org>
>> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY 
>> detect timeout
>>
>> The SATA spec mandates that link detection by the PHY completes 
>> within
>> 10 ms after receiving a reset signal. However, there is no obligation 
>> to uphold this requirement at the driver end as strictly as we do, 
>> and as it turns out, some combinations of host and device (e.g., 
>> Samsung
>> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>>
>> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>>
>> Contributed-under: TianoCore Contribution Agreement 1.0
>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>> ---
>> v2: update comment in AhciModeInitialization() as well
>>
>>  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++-- 
>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>>  2 files changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> index 4d01c1dd7fca..4418e5c3763e 100644
>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>>        AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>>
>>        //
>> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
>> -      // It's the requirment from SATA1.0a spec section 5.2.
>> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
>> +      // It's the requirement from SATA1.0a spec section 5.2.
>> +      // Add a bit of margin for robustness.
>>        //
>>        PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>>        Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH 
>> + EFI_AHCI_PORT_SSTS; diff --git 
>> a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> index 6401fb2e9fcd..809bcc307fc4 100644
>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>> @@ -41,8 +41,9 @@ typedef union {
>>
>>  //
>>  // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
>> +// Add a bit of margin for robustness.
>>  //
>> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
>> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>>  //
>>  // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>>  //
>> --
>> 2.9.3
>>
>> _______________________________________________
>> edk2-devel mailing list
>> edk2-devel@lists.01.org
>> https://lists.01.org/mailman/listinfo/edk2-devel
_______________________________________________
edk2-devel mailing list
edk2-devel@lists.01.org
https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Ard Biesheuvel]

> On 28 Jun 2017, at 09:53, Zeng, Star <star.zeng@intel.com> wrote:
> 
> The real delay may be 0ms if the DET register value just pass the check after the first AhciReadReg().
> But what does "Wait at least 10 ms" mean?
> 

If there is a link, it may be detected in 0 ms. If there is no link, it will take at least 10 ms to proceed, given that the phy may legally take 10 ms to report presence of a link. So we can never report 'no link' in less than 10 ms.

Or am I missing something here?


> 
> -----Original Message-----
> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of Ard Biesheuvel
> Sent: Wednesday, June 28, 2017 4:58 PM
> To: Tian, Feng <feng.tian@intel.com>
> Cc: leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric <eric.dong@intel.com>; Zeng, Star <star.zeng@intel.com>
> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout
> 
>> On 28 June 2017 at 08:49, Tian, Feng <feng.tian@intel.com> wrote:
>> Ard & Star,
>> 
>> I agree this patch to solve device compatible issue as it has no side effect for normal case.
>> 
>> Just a minor correction:
>> SATA 2.5 spec says: "If a device is present, the Phy shall take no longer than 10 ms to indicate that it has detected the presence of a device". That's why the original code think it *MUST* be less than 10ms.
>> 
> 
> Yes, I see where the confusion comes from. But the SATA spec primarily describes the requirements for the hardware side, which are the opposite of those for the software side.
> 
> Thanks,
> Ard.
> 
> 
>> -----Original Message-----
>> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
>> Sent: Wednesday, June 28, 2017 4:43 PM
>> To: Zeng, Star <star.zeng@intel.com>
>> Cc: edk2-devel@lists.01.org; Tian, Feng <feng.tian@intel.com>; Dong, 
>> Eric <eric.dong@intel.com>; leif.lindholm@linaro.org
>> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax 
>> PHY detect timeout
>> 
>>> On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
>>> The updated comments "Wait at least 10 ms" seems not correct.
>>> 
>> 
>> That is the whole point of the change. The SATA spec mandates that the 
>> PHY respond within 10 ms. It does *not* mandate that the software wait
>> 10 ms or less, rather the opposite, i.e., that the software should wait 10 ms or *more*, so 'at least 10ms'. The original comment said that the software *must* wait for no more than 10 ms, but this is not what the spec says.
>> 
>> 
>> 
>>> -----Original Message-----
>>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf 
>>> Of Ard Biesheuvel
>>> Sent: Wednesday, June 28, 2017 4:23 PM
>>> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
>>> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric 
>>> <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel 
>>> <ard.biesheuvel@linaro.org>
>>> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY 
>>> detect timeout
>>> 
>>> The SATA spec mandates that link detection by the PHY completes 
>>> within
>>> 10 ms after receiving a reset signal. However, there is no obligation 
>>> to uphold this requirement at the driver end as strictly as we do, 
>>> and as it turns out, some combinations of host and device (e.g., 
>>> Samsung
>>> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>>> 
>>> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>>> 
>>> Contributed-under: TianoCore Contribution Agreement 1.0
>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>> ---
>>> v2: update comment in AhciModeInitialization() as well
>>> 
>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++-- 
>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>>> 2 files changed, 5 insertions(+), 3 deletions(-)
>>> 
>>> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> index 4d01c1dd7fca..4418e5c3763e 100644
>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>>>       AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>>> 
>>>       //
>>> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
>>> -      // It's the requirment from SATA1.0a spec section 5.2.
>>> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
>>> +      // It's the requirement from SATA1.0a spec section 5.2.
>>> +      // Add a bit of margin for robustness.
>>>       //
>>>       PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>>>       Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH 
>>> + EFI_AHCI_PORT_SSTS; diff --git 
>>> a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> index 6401fb2e9fcd..809bcc307fc4 100644
>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> @@ -41,8 +41,9 @@ typedef union {
>>> 
>>> //
>>> // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
>>> +// Add a bit of margin for robustness.
>>> //
>>> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
>>> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>>> //
>>> // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>>> //
>>> --
>>> 2.9.3
>>> 
>>> _______________________________________________
>>> edk2-devel mailing list
>>> edk2-devel@lists.01.org
>>> https://lists.01.org/mailman/listinfo/edk2-devel
> _______________________________________________
> edk2-devel mailing list
> edk2-devel@lists.01.org
> https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Zeng, Star]

The delay duration may be 0 - EFI_AHCI_BUS_PHY_DETECT_TIMEOUT ms, and the comments are for all cases, but not for specific cases.

How about to just simplify the comments like below?

      //
      // Wait the Phy to detect the presence of a device.
      //

Thanks,
Star
-----Original Message-----
From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org] 
Sent: Wednesday, June 28, 2017 5:58 PM
To: Zeng, Star <star.zeng@intel.com>
Cc: Tian, Feng <feng.tian@intel.com>; leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric <eric.dong@intel.com>
Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout


> On 28 Jun 2017, at 09:53, Zeng, Star <star.zeng@intel.com> wrote:
> 
> The real delay may be 0ms if the DET register value just pass the check after the first AhciReadReg().
> But what does "Wait at least 10 ms" mean?
> 

If there is a link, it may be detected in 0 ms. If there is no link, it will take at least 10 ms to proceed, given that the phy may legally take 10 ms to report presence of a link. So we can never report 'no link' in less than 10 ms.

Or am I missing something here?


> 
> -----Original Message-----
> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of 
> Ard Biesheuvel
> Sent: Wednesday, June 28, 2017 4:58 PM
> To: Tian, Feng <feng.tian@intel.com>
> Cc: leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric 
> <eric.dong@intel.com>; Zeng, Star <star.zeng@intel.com>
> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax 
> PHY detect timeout
> 
>> On 28 June 2017 at 08:49, Tian, Feng <feng.tian@intel.com> wrote:
>> Ard & Star,
>> 
>> I agree this patch to solve device compatible issue as it has no side effect for normal case.
>> 
>> Just a minor correction:
>> SATA 2.5 spec says: "If a device is present, the Phy shall take no longer than 10 ms to indicate that it has detected the presence of a device". That's why the original code think it *MUST* be less than 10ms.
>> 
> 
> Yes, I see where the confusion comes from. But the SATA spec primarily describes the requirements for the hardware side, which are the opposite of those for the software side.
> 
> Thanks,
> Ard.
> 
> 
>> -----Original Message-----
>> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
>> Sent: Wednesday, June 28, 2017 4:43 PM
>> To: Zeng, Star <star.zeng@intel.com>
>> Cc: edk2-devel@lists.01.org; Tian, Feng <feng.tian@intel.com>; Dong, 
>> Eric <eric.dong@intel.com>; leif.lindholm@linaro.org
>> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax 
>> PHY detect timeout
>> 
>>> On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
>>> The updated comments "Wait at least 10 ms" seems not correct.
>>> 
>> 
>> That is the whole point of the change. The SATA spec mandates that 
>> the PHY respond within 10 ms. It does *not* mandate that the software 
>> wait
>> 10 ms or less, rather the opposite, i.e., that the software should wait 10 ms or *more*, so 'at least 10ms'. The original comment said that the software *must* wait for no more than 10 ms, but this is not what the spec says.
>> 
>> 
>> 
>>> -----Original Message-----
>>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf 
>>> Of Ard Biesheuvel
>>> Sent: Wednesday, June 28, 2017 4:23 PM
>>> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
>>> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric 
>>> <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel 
>>> <ard.biesheuvel@linaro.org>
>>> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY 
>>> detect timeout
>>> 
>>> The SATA spec mandates that link detection by the PHY completes 
>>> within
>>> 10 ms after receiving a reset signal. However, there is no 
>>> obligation to uphold this requirement at the driver end as strictly 
>>> as we do, and as it turns out, some combinations of host and device 
>>> (e.g., Samsung
>>> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>>> 
>>> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>>> 
>>> Contributed-under: TianoCore Contribution Agreement 1.0
>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>> ---
>>> v2: update comment in AhciModeInitialization() as well
>>> 
>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++-- 
>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>>> 2 files changed, 5 insertions(+), 3 deletions(-)
>>> 
>>> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> index 4d01c1dd7fca..4418e5c3763e 100644
>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>>>       AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>>> 
>>>       //
>>> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
>>> -      // It's the requirment from SATA1.0a spec section 5.2.
>>> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
>>> +      // It's the requirement from SATA1.0a spec section 5.2.
>>> +      // Add a bit of margin for robustness.
>>>       //
>>>       PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>>>       Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH
>>> + EFI_AHCI_PORT_SSTS; diff --git
>>> a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> index 6401fb2e9fcd..809bcc307fc4 100644
>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>> @@ -41,8 +41,9 @@ typedef union {
>>> 
>>> //
>>> // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
>>> +// Add a bit of margin for robustness.
>>> //
>>> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
>>> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>>> //
>>> // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>>> //
>>> --
>>> 2.9.3
>>> 
>>> _______________________________________________
>>> edk2-devel mailing list
>>> edk2-devel@lists.01.org
>>> https://lists.01.org/mailman/listinfo/edk2-devel
> _______________________________________________
> edk2-devel mailing list
> edk2-devel@lists.01.org
> https://lists.01.org/mailman/listinfo/edk2-devel

Re: [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout

[Ard Biesheuvel]

On 28 June 2017 at 10:44, Zeng, Star <star.zeng@intel.com> wrote:
> The delay duration may be 0 - EFI_AHCI_BUS_PHY_DETECT_TIMEOUT ms, and the comments are for all cases, but not for specific cases.
>
> How about to just simplify the comments like below?
>
>       //
>       // Wait the Phy to detect the presence of a device.
>       //
>

OK, I will change it.

> -----Original Message-----
> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
> Sent: Wednesday, June 28, 2017 5:58 PM
> To: Zeng, Star <star.zeng@intel.com>
> Cc: Tian, Feng <feng.tian@intel.com>; leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric <eric.dong@intel.com>
> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY detect timeout
>
>
>> On 28 Jun 2017, at 09:53, Zeng, Star <star.zeng@intel.com> wrote:
>>
>> The real delay may be 0ms if the DET register value just pass the check after the first AhciReadReg().
>> But what does "Wait at least 10 ms" mean?
>>
>
> If there is a link, it may be detected in 0 ms. If there is no link, it will take at least 10 ms to proceed, given that the phy may legally take 10 ms to report presence of a link. So we can never report 'no link' in less than 10 ms.
>
> Or am I missing something here?
>
>
>>
>> -----Original Message-----
>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf Of
>> Ard Biesheuvel
>> Sent: Wednesday, June 28, 2017 4:58 PM
>> To: Tian, Feng <feng.tian@intel.com>
>> Cc: leif.lindholm@linaro.org; edk2-devel@lists.01.org; Dong, Eric
>> <eric.dong@intel.com>; Zeng, Star <star.zeng@intel.com>
>> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax
>> PHY detect timeout
>>
>>> On 28 June 2017 at 08:49, Tian, Feng <feng.tian@intel.com> wrote:
>>> Ard & Star,
>>>
>>> I agree this patch to solve device compatible issue as it has no side effect for normal case.
>>>
>>> Just a minor correction:
>>> SATA 2.5 spec says: "If a device is present, the Phy shall take no longer than 10 ms to indicate that it has detected the presence of a device". That's why the original code think it *MUST* be less than 10ms.
>>>
>>
>> Yes, I see where the confusion comes from. But the SATA spec primarily describes the requirements for the hardware side, which are the opposite of those for the software side.
>>
>> Thanks,
>> Ard.
>>
>>
>>> -----Original Message-----
>>> From: Ard Biesheuvel [mailto:ard.biesheuvel@linaro.org]
>>> Sent: Wednesday, June 28, 2017 4:43 PM
>>> To: Zeng, Star <star.zeng@intel.com>
>>> Cc: edk2-devel@lists.01.org; Tian, Feng <feng.tian@intel.com>; Dong,
>>> Eric <eric.dong@intel.com>; leif.lindholm@linaro.org
>>> Subject: Re: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax
>>> PHY detect timeout
>>>
>>>> On 28 June 2017 at 08:31, Zeng, Star <star.zeng@intel.com> wrote:
>>>> The updated comments "Wait at least 10 ms" seems not correct.
>>>>
>>>
>>> That is the whole point of the change. The SATA spec mandates that
>>> the PHY respond within 10 ms. It does *not* mandate that the software
>>> wait
>>> 10 ms or less, rather the opposite, i.e., that the software should wait 10 ms or *more*, so 'at least 10ms'. The original comment said that the software *must* wait for no more than 10 ms, but this is not what the spec says.
>>>
>>>
>>>
>>>> -----Original Message-----
>>>> From: edk2-devel [mailto:edk2-devel-bounces@lists.01.org] On Behalf
>>>> Of Ard Biesheuvel
>>>> Sent: Wednesday, June 28, 2017 4:23 PM
>>>> To: edk2-devel@lists.01.org; Zeng, Star <star.zeng@intel.com>
>>>> Cc: Tian, Feng <feng.tian@intel.com>; Dong, Eric
>>>> <eric.dong@intel.com>; leif.lindholm@linaro.org; Ard Biesheuvel
>>>> <ard.biesheuvel@linaro.org>
>>>> Subject: [edk2] [PATCH v2] MdeModulePkg/AtaAtapiPassThru: relax PHY
>>>> detect timeout
>>>>
>>>> The SATA spec mandates that link detection by the PHY completes
>>>> within
>>>> 10 ms after receiving a reset signal. However, there is no
>>>> obligation to uphold this requirement at the driver end as strictly
>>>> as we do, and as it turns out, some combinations of host and device
>>>> (e.g., Samsung
>>>> 850 EVO connected to a LeMaker Cello) are only borderline compliant, which means the device is not detected reliably.
>>>>
>>>> So let's allow for a bit of margin, and increase the PHY detect timeout value to 15 ms.
>>>>
>>>> Contributed-under: TianoCore Contribution Agreement 1.0
>>>> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>>>> ---
>>>> v2: update comment in AhciModeInitialization() as well
>>>>
>>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c | 5 +++--
>>>> MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h | 3 ++-
>>>> 2 files changed, 5 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>>> index 4d01c1dd7fca..4418e5c3763e 100644
>>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.c
>>>> @@ -2376,8 +2376,9 @@ AhciModeInitialization (
>>>>       AhciOrReg (PciIo, Offset, EFI_AHCI_PORT_CMD_FRE);
>>>>
>>>>       //
>>>> -      // Wait no longer than 10 ms to wait the Phy to detect the presence of a device.
>>>> -      // It's the requirment from SATA1.0a spec section 5.2.
>>>> +      // Wait at least 10 ms for the Phy to detect the presence of a device.
>>>> +      // It's the requirement from SATA1.0a spec section 5.2.
>>>> +      // Add a bit of margin for robustness.
>>>>       //
>>>>       PhyDetectDelay = EFI_AHCI_BUS_PHY_DETECT_TIMEOUT;
>>>>       Offset = EFI_AHCI_PORT_START + Port * EFI_AHCI_PORT_REG_WIDTH
>>>> + EFI_AHCI_PORT_SSTS; diff --git
>>>> a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>>> b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>>> index 6401fb2e9fcd..809bcc307fc4 100644
>>>> --- a/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>>> +++ b/MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AhciMode.h
>>>> @@ -41,8 +41,9 @@ typedef union {
>>>>
>>>> //
>>>> // Refer SATA1.0a spec section 5.2, the Phy detection time should be less than 10ms.
>>>> +// Add a bit of margin for robustness.
>>>> //
>>>> -#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       10
>>>> +#define  EFI_AHCI_BUS_PHY_DETECT_TIMEOUT       15
>>>> //
>>>> // Refer SATA1.0a spec, the FIS enable time should be less than 500ms.
>>>> //
>>>> --
>>>> 2.9.3
>>>>
>>>> _______________________________________________
>>>> edk2-devel mailing list
>>>> edk2-devel@lists.01.org
>>>> https://lists.01.org/mailman/listinfo/edk2-devel
>> _______________________________________________
>> edk2-devel mailing list
>> edk2-devel@lists.01.org
>> https://lists.01.org/mailman/listinfo/edk2-devel