RE: [PATCH v2 4/4] EDAC: synopsys: Add useful debug and output information for 64bit systems

[Sherry Sun]

Hi Robert,

> -----Original Message-----
> From: Robert Richter <rrichter@xxxxxxxxxxx>
> Sent: 2020年4月2日 15:20
> To: Sherry Sun <sherry.sun@xxxxxxx>
> Cc: bp@xxxxxxxxx; mchehab@xxxxxxxxxx; tony.luck@xxxxxxxxx;
> james.morse@xxxxxxx; michal.simek@xxxxxxxxxx;
> manish.narani@xxxxxxxxxx; linux-edac@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; Frank Li <frank.li@xxxxxxx>
> Subject: Re: [PATCH v2 4/4] EDAC: synopsys: Add useful debug and output
> information for 64bit systems
> 
> On 01.04.20 14:32:58, Sherry Sun wrote:
> > > From: Robert Richter <rrichter@xxxxxxxxxxx> On 01.04.20 15:39:09,
> > > Sherry Sun wrote:
> 
> > > > --- a/drivers/edac/synopsys_edac.c
> > > > +++ b/drivers/edac/synopsys_edac.c
> > > > @@ -278,18 +278,22 @@
> > > >   * @col:	Column number.
> > > >   * @bank:	Bank number.
> > > >   * @bitpos:	Bit position.
> > > > - * @data:	Data causing the error.
> > > > + * @data_low:	Low bit data causing the error.
> > > > + * @data_high:	High bit data causing the error(used for 64 bit
> > > systems).
> > > >   * @bankgrpnr:	Bank group number.
> > > >   * @blknr:	Block number.
> > > > + * @syndrome:	Syndrome of the error.
> > > >   */
> > > >  struct ecc_error_info {
> > > >  	u32 row;
> > > >  	u32 col;
> > > >  	u32 bank;
> > > >  	u32 bitpos;
> > > > -	u32 data;
> > > > +	u32 data_low;
> > > > +	u32 data_high;
> > >
> > > Where are 16, 32 and 64 bit widths. You could handle them all the
> > > same in a u64.
> > >
> > > If I am not wrong, the width is fix for the whole mci. So you could
> > > create various .get_error_info() functions depending on the data
> > > width without run time width checks.
> > >
> >
> > Yes, here we can use u64. Will correct it in v3.
> > For the zynq, it's 16-bit bus width, for imx8mp, it's 64-bit bus width.
> > But for zynqmp, it's optional between 32-bit and 64-bit bus width, So
> > we had better run time check the bus width, what do you think?
> 
> I am wondering a bit here. *get_dtype() is used only in init_csrows() which
> sets up the mci. So it will be a fix value all the time after init. With that you
> easily can setup functions depending on the width, alternatively the width
> could be stored in struct synps_platform_data or struct synps_edac_priv.
> 

Yes, I think your suggestion is reasonable, I will have a try later.

> >
> > > >  	u32 bankgrpnr;
> > > >  	u32 blknr;
> > > > +	u32 syndrome;
> > > >  };
> 
> > > @@ -480,20
> > > > +559,27 @@ static void handle_error(struct mem_ctl_info *mci,
> > > > +struct
> > > > synps_ecc_status *p)  {
> > > >  	struct synps_edac_priv *priv = mci->pvt_info;
> > > >  	struct ecc_error_info *pinf;
> > > > +	int n;
> > > >
> > > >  	if (p->ce_cnt) {
> > > >  		pinf = &p->ceinfo;
> > > >  		if (priv->p_data->quirks & DDR_ECC_INTR_SUPPORT) {
> > > > -			snprintf(priv->message, SYNPS_EDAC_MSG_SIZE,
> > > > -				 "DDR ECC error type:%s Row %d Bank %d
> > > BankGroup Number %d Block Number %d Bit Position: %d Data: 0x%08x",
> > > > -				 "CE", pinf->row, pinf->bank,
> > > > -				 pinf->bankgrpnr, pinf->blknr,
> > > > -				 pinf->bitpos, pinf->data);
> > > > +			n = snprintf(priv->message, SYNPS_EDAC_MSG_SIZE,
> > > > +				     "DDR ECC error type:%s Row %d Bank %d
> > > BankGroup Number %d Block Number %d Bit Position: %d Data: 0x%08x",
> > > > +				     "CE", pinf->row, pinf->bank,
> > > > +				     pinf->bankgrpnr, pinf->blknr,
> > > > +				     pinf->bitpos, pinf->data_low);
> > > > +
> > > > +			if (zynqmp_get_dtype(priv->baseaddr) == DEV_X8)
> > >
> > > This is zynqmp specific, right? but you call it in the generic
> > > function handle_error().
> >
> > Yes, although handle_error() is a generic function, but this operation
> > is checked by priv->p_data->quirks, so here is zynqmp and imx8mp
> > specific.
> 
> Naah, this is a bit hacky, just make 2 variants of handlers and set them up
> during init. Storing the width in some private data would be an alternative.
> 

Okay, I will try to store the bus width in private data.Thanks.

Best regards
Sherry Sun

> Thanks,
> 
> -Robert
> 
> >
> > Best regards
> > Sherry Sun
> >
> > >
> > > -Robert
> > >
> > > > +				snprintf(priv->message + n,
> > > > +					 SYNPS_EDAC_MSG_SIZE - n,
> > > > +					 " Data_high: 0x%08x Syndrome:
> > > 0x%08x",
> > > > +					 pinf->data_high, pinf->syndrome);
> > > >  		} else {
> > > >  			snprintf(priv->message, SYNPS_EDAC_MSG_SIZE,
> > > >  				 "DDR ECC error type:%s Row %d Bank %d
> > > Col %d Bit Position: %d Data: 0x%08x",
> > > >  				 "CE", pinf->row, pinf->bank, pinf->col,
> > > > -				 pinf->bitpos, pinf->data);
> > > > +				 pinf->bitpos, pinf->data_low);
> > > >  		}
> > > >
> > > >  		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,