Re: [PATCHv1] fpga: stratix10-soc: remove the pre-set reconfiguration condition

From: Richard Gong <richard.gong@linux.intel.com>
To: Moritz Fischer <mdf@kernel.org>
Cc: linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org,
	dinguyen@kernel.org, Richard Gong <richard.gong@intel.com>
Subject: Re: [PATCHv1] fpga: stratix10-soc: remove the pre-set reconfiguration condition
Date: Tue, 12 May 2020 16:27:02 -0500	[thread overview]
Message-ID: <5c23279d-17be-f33c-469c-461219027465@linux.intel.com> (raw)
In-Reply-To: <20200512153514.GA125665@epycbox.lan>

Hi Moritz,

On 5/12/20 10:35 AM, Moritz Fischer wrote:
> Hi Richard,
> 
> On Tue, May 12, 2020 at 08:27:31AM -0500, richard.gong@linux.intel.com wrote:
>> From: Richard Gong <richard.gong@intel.com>
>>
>> The reconfiguration mode is pre-set by driver as the full reconfiguration.
>> As a result, user have to change code and recompile the drivers if he or
>> she wants to perform a partial reconfiguration. Removing the pre-set
>> reconfiguration condition so that user can select full or partial
>> reconfiguration via overlay device tree without recompiling the drivers.
>>
>> Also add an error message if the configuration request is failure.
>>
>> Signed-off-by: Richard Gong <richard.gong@intel.com>
>> ---
>>   drivers/fpga/stratix10-soc.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
>> index 44b7c56..2da8a40 100644
>> --- a/drivers/fpga/stratix10-soc.c
>> +++ b/drivers/fpga/stratix10-soc.c
>> @@ -182,12 +182,12 @@ static int s10_ops_write_init(struct fpga_manager *mgr,
>>   	uint i;
>>   	int ret;
>>   
>> -	ctype.flags = 0;
>>   	if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
>>   		dev_dbg(dev, "Requesting partial reconfiguration.\n");
>> -		ctype.flags |= BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
>> +		ctype.flags = 1;
> Have you considered:
> 
> ctype.flags = BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
> 
> instead (assuming 1, lines up with BIT(COMMAND_RECONFIG_FLAG_PARTIAL)?
> 
> If not: Can you define a constant?

How about change below?

+#define RECONFIG_FLAG_FULL             0
+#define RECONFIG_FLAG_PARTIAL          1
+
  /*
   * struct s10_svc_buf
   * buf:  virtual address of buf provided by service layer
@@ -184,10 +187,10 @@ static int s10_ops_write_init(struct fpga_manager 
*mgr,

         if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
                 dev_dbg(dev, "Requesting partial reconfiguration.\n");
-               ctype.flags = 1;
+               ctype.flags = RECONFIG_FLAG_PARTIAL;
         } else {
                 dev_dbg(dev, "Requesting full reconfiguration.\n");
-               ctype.flags = 0;
+               ctype.flags = RECONFIG_FLAG_FULL;
         }

The protocol between kernel driver and the firmware:
The reconfiguration flag for full or partial configuration. 0 is for 
full (default mode) and 1 for partial reconfiguration.

I will submit a new version.

Regards,
Richard

>>   	} else {
>>   		dev_dbg(dev, "Requesting full reconfiguration.\n");
>> +		ctype.flags = 0;
>>   	}
>>   
>>   	reinit_completion(&priv->status_return_completion);
>> @@ -210,6 +210,7 @@ static int s10_ops_write_init(struct fpga_manager *mgr,
>>   
>>   	ret = 0;
>>   	if (!test_and_clear_bit(SVC_STATUS_OK, &priv->status)) {
>> +		dev_err(dev, "RECONFIG_REQUEST failed\n");
>>   		ret = -ETIMEDOUT;
>>   		goto init_done;
>>   	}
>> -- 
>> 2.7.4
>>
> 
> Cheers,
> Moritz
> 
