On 15/01/2014 16:09, boris brezillon wrote:
Hello Jason,
On 09/01/2014 18:35, Jason Gunthorpe wrote:
On Thu, Jan 09, 2014 at 09:36:18AM +0100, boris brezillon wrote:
You might want to check if you can boil down the DT timings from the
huge list to just an ONFI mode number..
Sure, but the sunxi driver needs at least 19 of them...
So does mvebu's NAND driver..
What I ment was you could have a
onfi,nand-timing-mode = 0
in the DT. Each of the modes defines all ~19 parameters, higher modes
are faster.
Pick a mode value that fits all the parameters of the connected
non-ONFI flash.
This would be instead of defining each parameter
individually.. Provide some helpers to convert from a onfi mode number
to all the onfi defined timing parameters so that drivers can
configure the HW..
Are you suggesting we should provide a function that converts these
modes into a nand_timings struct, or just use the timing modes and
let the NAND controller drivers configure its IP accordingly ?
I found the ONFI timing tables in this document:
www.*onfi*.org/~/media/*ONFI*/specs/*onfi*_3_1_spec.pdf (chapter 4.16).
I suppose my nand_timings struct should use the names described
page 110-111 (at least if we decide to use nand_timings and not
nand_timing_modes), right ?
After taking a closer look at this document, the only parameter
available in my
nand_timings struct that is not defined in the standard is tR_max (data
transfer
from cell to register).
And the ONFI standard defines 4 more timings:
- tCEA_max
- tCEH_min
- tFEAT_max
- tITC_max
Best Regards,
Boris
Jason
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