Re: [Qemu-devel] [PATCH 4/9] m25p80: Introduce COLLECTING_VAR_LEN_DATA state.

["Cédric Le Goater" <clg@kaod.org>]

On 06/16/2016 09:43 AM, Krzeminski, Marcin (Nokia - PL/Wroclaw) wrote:
> 
> 
>> -----Original Message-----
>> From: Cédric Le Goater [mailto:clg@kaod.org]
>> Sent: Thursday, June 16, 2016 9:14 AM
>> To: Krzeminski, Marcin (Nokia - PL/Wroclaw)
>> <marcin.krzeminski@nokia.com>; qemu-devel@nongnu.org
>> Cc: crosthwaitepeter@gmail.com; pawel.lenkow@itlen.com;
>> peter.maydell@linaro.org
>> Subject: Re: [PATCH 4/9] m25p80: Introduce COLLECTING_VAR_LEN_DATA
>> state.
>>
>> On 06/15/2016 03:41 PM, marcin.krzeminski@nokia.com wrote:
>>> From: Marcin Krzeminski <marcin.krzeminski@nokia.com>
>>>
>>> Some flash allows to stop read at any time.
>>> Allow framework to support this.
>>>
>>> Signed-off-by: Marcin Krzeminski <marcin.krzeminski@nokia.com>
>>> ---
>>>  hw/block/m25p80.c | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>>
>>> diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c index
>>> 6910c52..ca1f882 100644
>>> --- a/hw/block/m25p80.c
>>> +++ b/hw/block/m25p80.c
>>> @@ -330,6 +330,7 @@ typedef enum {
>>>      STATE_PAGE_PROGRAM,
>>>      STATE_READ,
>>>      STATE_COLLECTING_DATA,
>>> +    STATE_COLLECTING_VAR_LEN_DATA,
>>>      STATE_READING_DATA,
>>>  } CMDState;
>>>
>>> @@ -872,6 +873,9 @@ static int m25p80_cs(SSISlave *ss, bool select)
>>>      Flash *s = M25P80(ss);
>>>
>>>      if (select) {
>>> +        if (s->state == STATE_COLLECTING_VAR_LEN_DATA) {
>>> +            complete_collecting_data(s);
>>> +        }
>>
>> So for example, we could trigger an erase without a completed address ?
>>
>> C.
> Yes if you explicitly want that. This is new state and you need to go
> into it in decode_new_cmd.
> For now this is only used in WRSR command only.

OK. I see and I understand the use in that case.

Reviewed-by: Cédric Le Goater <clg@kaod.org>

C.


> 
> Thanks,
> Marcin
>>
>>>          s->len = 0;
>>>          s->pos = 0;
>>>          s->state = STATE_IDLE;
>>> @@ -905,6 +909,7 @@ static uint32_t m25p80_transfer8(SSISlave *ss,
>> uint32_t tx)
>>>          break;
>>>
>>>      case STATE_COLLECTING_DATA:
>>> +    case STATE_COLLECTING_VAR_LEN_DATA:
>>>          s->data[s->len] = (uint8_t)tx;
>>>          s->len++;
>>>
>