Hello Jason,
Le 08/01/2014 19:34, Jason Gunthorpe a écrit :
On Wed, Jan 08, 2014 at 03:21:58PM +0100, Boris BREZILLON wrote:
+int of_get_nand_timings(struct device_node *np, struct nand_timings *timings)
+{
+ memset(timings, 0, sizeof(*timings));
+ of_property_read_u32(np, "tCLS-min", &timings->tCLS_min);
+ of_property_read_u32(np, "tCLH-min", &timings->tCLH_min);
+ of_property_read_u32(np, "tCS-min", &timings->tCS_min);
[..]
A while ago when discussing another controller it was pointed out
these values are all auto-probable directly from the NAND via a ONFI
defined GET FEATURE @0x01 query, and adding these timings to the DT
was NAK'd..
Basically you set the interface to the slowest ONFI timing mode, do
the GET FEATURE to the NAND chip and then increase the interface speed
to the highest mutually supported ONFI mode.
Is there some reason you need to encode this in the DT?
What if the NAND does not support the ONFI interface (and this is
exactly the case for the NAND available on the cubietruck board:
H27UCG8T2ATR).
But I'm glag to hear about this ONFI feature :).
I'll add a function to retrieve these timings if the NAND support
the ONFI interface.
Best Regards,
Boris
Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-doc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html