diff mbox series

[RFC,v42,90/98] hw/sd/sdcard: Add experimental 'x-aspeed-emmc-kludge' property

Message ID 20240628070216.92609-91-philmd@linaro.org (mailing list archive)
State New, archived
Headers show
Series hw/sd/sdcard: Add eMMC support | expand

Commit Message

Philippe Mathieu-Daudé June 28, 2024, 7:02 a.m. UTC
When booting U-boot/Linux on Aspeed boards via eMMC,
some commands don't behave as expected from the spec.

Add the 'x-aspeed-emmc-kludge' property to allow non
standard uses until we figure out the reasons.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sd/sd.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Cédric Le Goater June 28, 2024, 9:16 a.m. UTC | #1
On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
> When booting U-boot/Linux on Aspeed boards via eMMC,
> some commands don't behave as expected from the spec.
> 
> Add the 'x-aspeed-emmc-kludge' property to allow non
> standard uses until we figure out the reasons.

I am not aware of any singularity in the eMMC logic provided by Aspeed.
U-Boot and Linux drivers seem very generic. May be others can tell.

Thanks,

C.


  
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   hw/sd/sd.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/hw/sd/sd.c b/hw/sd/sd.c
> index bd77853419..dc692fe1fa 100644
> --- a/hw/sd/sd.c
> +++ b/hw/sd/sd.c
> @@ -127,6 +127,7 @@ struct SDState {
>   
>       uint8_t spec_version;
>       BlockBackend *blk;
> +    bool aspeed_emmc_kludge;
>   
>       const SDProto *proto;
>   
> @@ -2567,6 +2568,8 @@ static Property sd_properties[] = {
>       DEFINE_PROP_UINT8("spec_version", SDState,
>                         spec_version, SD_PHY_SPECv3_01_VERS),
>       DEFINE_PROP_DRIVE("drive", SDState, blk),
> +    DEFINE_PROP_BOOL("x-aspeed-emmc-kludge", SDState,
> +                     aspeed_emmc_kludge, false),
>       /* We do not model the chip select pin, so allow the board to select
>        * whether card should be in SSI or MMC/SD mode.  It is also up to the
>        * board to ensure that ssi transfers only occur when the chip select
Andrew Jeffery July 2, 2024, 5:06 a.m. UTC | #2
On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
> > When booting U-boot/Linux on Aspeed boards via eMMC,
> > some commands don't behave as expected from the spec.
> > 
> > Add the 'x-aspeed-emmc-kludge' property to allow non
> > standard uses until we figure out the reasons.
> 
> I am not aware of any singularity in the eMMC logic provided by Aspeed.
> U-Boot and Linux drivers seem very generic. May be others can tell.

I'm not aware of any command kludges. The main problem I had when I
wrote the Linux driver for the Aspeed controller was the phase tuning,
but that doesn't sound related.

Andrew
Philippe Mathieu-Daudé July 2, 2024, 4:15 p.m. UTC | #3
On 2/7/24 07:06, Andrew Jeffery wrote:
> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>> some commands don't behave as expected from the spec.
>>>
>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>> standard uses until we figure out the reasons.
>>
>> I am not aware of any singularity in the eMMC logic provided by Aspeed.
>> U-Boot and Linux drivers seem very generic. May be others can tell.
> 
> I'm not aware of any command kludges. The main problem I had when I
> wrote the Linux driver for the Aspeed controller was the phase tuning,
> but that doesn't sound related.

Yeah I don't think anything Aspeed nor U-boot related, we
model CSD/CID registers per the SD spec, not MMC. Various
fields are identical, but few differ, this might be the
problem.

I rather respect the spec by default, so until we figure
the issue, are you OK to use a 'x-emmc-kludge' property
and set it on the Aspeed boards?
Cédric Le Goater July 2, 2024, 4:21 p.m. UTC | #4
On 7/2/24 6:15 PM, Philippe Mathieu-Daudé wrote:
> On 2/7/24 07:06, Andrew Jeffery wrote:
>> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>>> some commands don't behave as expected from the spec.
>>>>
>>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>>> standard uses until we figure out the reasons.
>>>
>>> I am not aware of any singularity in the eMMC logic provided by Aspeed.
>>> U-Boot and Linux drivers seem very generic. May be others can tell.
>>
>> I'm not aware of any command kludges. The main problem I had when I
>> wrote the Linux driver for the Aspeed controller was the phase tuning,
>> but that doesn't sound related.
> 
> Yeah I don't think anything Aspeed nor U-boot related, we
> model CSD/CID registers per the SD spec, not MMC. Various
> fields are identical, but few differ, this might be the
> problem.
> 
> I rather respect the spec by default, so until we figure
> the issue, are you OK to use a 'x-emmc-kludge' property
> and set it on the Aspeed boards?

If these differences are eMMC related, why not simply test :

     if (sd_is_emmc(sd)) ...

in commands ALL_SEND_CID and APP_CMD ? The extra property looks
ambiguous to me.

Thanks,

C.
Philippe Mathieu-Daudé July 2, 2024, 8:05 p.m. UTC | #5
On 2/7/24 18:21, Cédric Le Goater wrote:
> On 7/2/24 6:15 PM, Philippe Mathieu-Daudé wrote:
>> On 2/7/24 07:06, Andrew Jeffery wrote:
>>> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>>>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>>>> some commands don't behave as expected from the spec.
>>>>>
>>>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>>>> standard uses until we figure out the reasons.
>>>>
>>>> I am not aware of any singularity in the eMMC logic provided by Aspeed.
>>>> U-Boot and Linux drivers seem very generic. May be others can tell.
>>>
>>> I'm not aware of any command kludges. The main problem I had when I
>>> wrote the Linux driver for the Aspeed controller was the phase tuning,
>>> but that doesn't sound related.
>>
>> Yeah I don't think anything Aspeed nor U-boot related, we
>> model CSD/CID registers per the SD spec, not MMC. Various
>> fields are identical, but few differ, this might be the
>> problem.
>>
>> I rather respect the spec by default, so until we figure
>> the issue, are you OK to use a 'x-emmc-kludge' property
>> and set it on the Aspeed boards?
> 
> If these differences are eMMC related, why not simply test :
> 
>      if (sd_is_emmc(sd)) ...
> 
> in commands ALL_SEND_CID and APP_CMD ? The extra property looks
> ambiguous to me.

I'd like to keep the sd_is_emmc() check for code respecting
the eMMC spec. I believe the commands in sd_proto_emmc[] in
this series do respect it, modulo some register field
definitions that are SD specific. So 'x-emmc-kludge' would
be a property to allow eMMC use -- without delaying it further
--, by bypassing a *bug* in our current model. I'm willing to
figure out the problem and fix it, but /after/ the 9.1 release.
We are too close of the soft freeze and trying to fix that
before is too much pressure on my right now.

> Thanks,
> 
> C.
> 
>
Philippe Mathieu-Daudé July 2, 2024, 8:07 p.m. UTC | #6
On 2/7/24 22:05, Philippe Mathieu-Daudé wrote:
> On 2/7/24 18:21, Cédric Le Goater wrote:
>> On 7/2/24 6:15 PM, Philippe Mathieu-Daudé wrote:
>>> On 2/7/24 07:06, Andrew Jeffery wrote:
>>>> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>>>>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>>>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>>>>> some commands don't behave as expected from the spec.
>>>>>>
>>>>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>>>>> standard uses until we figure out the reasons.
>>>>>
>>>>> I am not aware of any singularity in the eMMC logic provided by 
>>>>> Aspeed.
>>>>> U-Boot and Linux drivers seem very generic. May be others can tell.
>>>>
>>>> I'm not aware of any command kludges. The main problem I had when I
>>>> wrote the Linux driver for the Aspeed controller was the phase tuning,
>>>> but that doesn't sound related.
>>>
>>> Yeah I don't think anything Aspeed nor U-boot related, we
>>> model CSD/CID registers per the SD spec, not MMC. Various
>>> fields are identical, but few differ, this might be the
>>> problem.
>>>
>>> I rather respect the spec by default, so until we figure
>>> the issue, are you OK to use a 'x-emmc-kludge' property
>>> and set it on the Aspeed boards?
>>
>> If these differences are eMMC related, why not simply test :
>>
>>      if (sd_is_emmc(sd)) ...
>>
>> in commands ALL_SEND_CID and APP_CMD ? The extra property looks
>> ambiguous to me.
> 
> I'd like to keep the sd_is_emmc() check for code respecting
> the eMMC spec. I believe the commands in sd_proto_emmc[] in
> this series do respect it, modulo some register field
> definitions that are SD specific. So 'x-emmc-kludge' would
> be a property to allow eMMC use -- without delaying it further
> --, by bypassing a *bug* in our current model. I'm willing to
> figure out the problem and fix it, but /after/ the 9.1 release.
> We are too close of the soft freeze and trying to fix that
> before is too much pressure on my right now.

(Similar pressure I'm putting on you to review this huge series...)
Andrew Jeffery July 3, 2024, 5:10 a.m. UTC | #7
On Tue, 2024-07-02 at 18:15 +0200, Philippe Mathieu-Daudé wrote:
> On 2/7/24 07:06, Andrew Jeffery wrote:
> > On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
> > > On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
> > > > When booting U-boot/Linux on Aspeed boards via eMMC,
> > > > some commands don't behave as expected from the spec.
> > > > 
> > > > Add the 'x-aspeed-emmc-kludge' property to allow non
> > > > standard uses until we figure out the reasons.
> > > 
> > > I am not aware of any singularity in the eMMC logic provided by Aspeed.
> > > U-Boot and Linux drivers seem very generic. May be others can tell.
> > 
> > I'm not aware of any command kludges. The main problem I had when I
> > wrote the Linux driver for the Aspeed controller was the phase tuning,
> > but that doesn't sound related.
> 
> Yeah I don't think anything Aspeed nor U-boot related, we
> model CSD/CID registers per the SD spec, not MMC. Various
> fields are identical, but few differ, this might be the
> problem.
> 
> I rather respect the spec by default, so until we figure
> the issue, are you OK to use a 'x-emmc-kludge' property
> and set it on the Aspeed boards?

Dropping the implication that it's the fault of the Aspeed controller
seems reasonable (without further evidence that it's true).

Andrew
Cédric Le Goater July 3, 2024, 5:39 a.m. UTC | #8
On 7/3/24 7:10 AM, Andrew Jeffery wrote:
> On Tue, 2024-07-02 at 18:15 +0200, Philippe Mathieu-Daudé wrote:
>> On 2/7/24 07:06, Andrew Jeffery wrote:
>>> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>>>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>>>> some commands don't behave as expected from the spec.
>>>>>
>>>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>>>> standard uses until we figure out the reasons.
>>>>
>>>> I am not aware of any singularity in the eMMC logic provided by Aspeed.
>>>> U-Boot and Linux drivers seem very generic. May be others can tell.
>>>
>>> I'm not aware of any command kludges. The main problem I had when I
>>> wrote the Linux driver for the Aspeed controller was the phase tuning,
>>> but that doesn't sound related.
>>
>> Yeah I don't think anything Aspeed nor U-boot related, we
>> model CSD/CID registers per the SD spec, not MMC. Various
>> fields are identical, but few differ, this might be the
>> problem.
>>
>> I rather respect the spec by default, so until we figure
>> the issue, are you OK to use a 'x-emmc-kludge' property
>> and set it on the Aspeed boards?
> 
> Dropping the implication that it's the fault of the Aspeed controller
> seems reasonable (without further evidence that it's true).

Yes. Let's introduce 'x-emmc-kludge' and move on.

I dropped all emmc support from the aspeed-9.1 branch for now.

Thanks,

C.
Philippe Mathieu-Daudé July 3, 2024, 10:18 a.m. UTC | #9
On 2/7/24 22:05, Philippe Mathieu-Daudé wrote:
> On 2/7/24 18:21, Cédric Le Goater wrote:
>> On 7/2/24 6:15 PM, Philippe Mathieu-Daudé wrote:
>>> On 2/7/24 07:06, Andrew Jeffery wrote:
>>>> On Fri, 2024-06-28 at 11:16 +0200, Cédric Le Goater wrote:
>>>>> On 6/28/24 9:02 AM, Philippe Mathieu-Daudé wrote:
>>>>>> When booting U-boot/Linux on Aspeed boards via eMMC,
>>>>>> some commands don't behave as expected from the spec.
>>>>>>
>>>>>> Add the 'x-aspeed-emmc-kludge' property to allow non
>>>>>> standard uses until we figure out the reasons.
>>>>>
>>>>> I am not aware of any singularity in the eMMC logic provided by 
>>>>> Aspeed.
>>>>> U-Boot and Linux drivers seem very generic. May be others can tell.
>>>>
>>>> I'm not aware of any command kludges. The main problem I had when I
>>>> wrote the Linux driver for the Aspeed controller was the phase tuning,
>>>> but that doesn't sound related.
>>>
>>> Yeah I don't think anything Aspeed nor U-boot related, we
>>> model CSD/CID registers per the SD spec, not MMC. Various
>>> fields are identical, but few differ, this might be the
>>> problem.
>>>
>>> I rather respect the spec by default, so until we figure
>>> the issue, are you OK to use a 'x-emmc-kludge' property
>>> and set it on the Aspeed boards?
>>
>> If these differences are eMMC related, why not simply test :
>>
>>      if (sd_is_emmc(sd)) ...
>>
>> in commands ALL_SEND_CID and APP_CMD ? The extra property looks
>> ambiguous to me.
> 
> I'd like to keep the sd_is_emmc() check for code respecting
> the eMMC spec. I believe the commands in sd_proto_emmc[] in
> this series do respect it, modulo some register field
> definitions that are SD specific. So 'x-emmc-kludge' would
> be a property to allow eMMC use -- without delaying it further
> --, by bypassing a *bug* in our current model. I'm willing to
> figure out the problem and fix it, but /after/ the 9.1 release.
> We are too close of the soft freeze and trying to fix that
> before is too much pressure on my right now.

The problem is in the still unreviewed patch #86 of this series
"hw/sd/sdcard: Add emmc_cmd_SEND_OP_COND handler (CMD1)".

SEND_OP_COND should put the card in READY state. We are not
considering the BOOT_PARTITION_ENABLE feature:

   > When BOOT_PARTITION_ENABLE bits are set and master send
   > CMD1 (SEND_OP_COND), slave must enter Card Identification
   > Mode and respond to the command.
   > If the slave does not support boot operation mode, which
   > is compliant with v4.2 or before, or BOOT_PARTITION_ENABLE
   > bit is cleared, slave automatically enter Idle State after
   > power-on.

Then we don't need the change in the next patch (#91) in
ALL_SEND_CID.

And likely neither we need #92 (APP_CMD ) but I still need
to confirm that.
diff mbox series

Patch

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index bd77853419..dc692fe1fa 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -127,6 +127,7 @@  struct SDState {
 
     uint8_t spec_version;
     BlockBackend *blk;
+    bool aspeed_emmc_kludge;
 
     const SDProto *proto;
 
@@ -2567,6 +2568,8 @@  static Property sd_properties[] = {
     DEFINE_PROP_UINT8("spec_version", SDState,
                       spec_version, SD_PHY_SPECv3_01_VERS),
     DEFINE_PROP_DRIVE("drive", SDState, blk),
+    DEFINE_PROP_BOOL("x-aspeed-emmc-kludge", SDState,
+                     aspeed_emmc_kludge, false),
     /* We do not model the chip select pin, so allow the board to select
      * whether card should be in SSI or MMC/SD mode.  It is also up to the
      * board to ensure that ssi transfers only occur when the chip select