Re: [PATCHv2] fpga: stratix10-soc: remove the pre-set reconfiguration condition

[Richard Gong]

Hi Moritz,


On 5/31/20 2:49 PM, Moritz Fischer wrote:
> On Fri, May 29, 2020 at 08:15:15AM -0500, Richard Gong wrote:
> > Hi Moritz,
> >
> > Sorry for asking.
> >
> > When you get chance, can you review my version 2 patch submitted on
> > 05/15/20?
> >
> > Regards,
> > Richard
> >
> > On 5/15/20 9:35 AM, richard.gong@xxxxxxxxxxxxxxx wrote:
> > > From: Richard Gong <richard.gong@xxxxxxxxx>
> > >
> > > 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.
>
> Can you help me understand? See comment below, I'm not sure how this
> change changes the behavior.

Flag COMMAND_RECONFIG_FLAG_PARTIAL is defined in Intel service layer 
driver (include/linux/firmware/intel/stratix10-svc-client.h) and the 
default value is zero. It is obvious that COMMAND_RECONFIG_FLAG_PARTIAL 
should be set to 1 to support partial reconfiguration.

Please discard this FPGA patch, I will submit a patch on Intel service 
layer driver.

Regards,
Richard

> > > Also add an error message if the configuration request is failure.
> > >
> > > Signed-off-by: Richard Gong <richard.gong@xxxxxxxxx>
> > > ---
> > > v2: define and use constant values
> > > ---
> > >    drivers/fpga/stratix10-soc.c | 9 +++++++--
> > >    1 file changed, 7 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
> > > index 44b7c56..4d52a80 100644
> > > --- a/drivers/fpga/stratix10-soc.c
> > > +++ b/drivers/fpga/stratix10-soc.c
> > > @@ -14,9 +14,13 @@
> > >    /*
> > >     * FPGA programming requires a higher level of privilege (EL3), per the SoC
> > >     * design.
> > > + * SoC firmware supports full and partial reconfiguration.
> Consider:
> "The SoC firmware supports full and partial reconfiguration."
> > >     */
> > >    #define NUM_SVC_BUFS	4
> > >    #define SVC_BUF_SIZE	SZ_512K
> > > +#define FULL_RECONFIG_FLAG	0
> > > +#define PARTIAL_RECONFIG_FLAG	1
> > > +
> > >    /* Indicates buffer is in use if set */
> > >    #define SVC_BUF_LOCK	0
> > > @@ -182,12 +186,12 @@ 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 = PARTIAL_RECONFIG_FLAG;
> > >    	} else {
> > >    		dev_dbg(dev, "Requesting full reconfiguration.\n");
> > > +		ctype.flags = FULL_RECONFIG_FLAG;
> > >    	}
> Am I missing something here: Doesn't this do the same as before?
>
> Before:
> If info->flags & FPGA_MGR_PARTIAL_RECONFIG -> ctype.flags = 0 |
> BIT(COMMAND_RECONFIG_FLAG_PARTIAL) -> 1
> and ctype->flags = FULL_RECONFIG -> 0 else.
>
> Now:
> If info->flags & FPGA_MGR_PARTIAL_RECONFIG -> ctype.flags = PARTIAL_RECONFIG_FLAG -> 1
> ctype->flags = FULL_REECONFIG_FLAG -> 0 else.
>
> Am I missing something here? If I don't set the flag for partial
> reconfig I'd end up with full reconfiguration in both cases?
> If I do set the flag, I get partial reconfiguration in both cases?
>
> > >    	reinit_completion(&priv->status_return_completion);
> > > @@ -210,6 +214,7 @@ 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;
> > >    	}
>
> Thanks,
> Moritz