On Mon, 2015-06-08 at 10:11 +0200, Roy Spliet wrote:
Hello Scott et al.,
Op 06-06-15 om 00:02 schreef Scott Wood:
On Fri, 2015-06-05 at 13:52 +0200, Roy Spliet wrote:
From: yassin yassinjaffer@gmail.com
Signed-off-by: Roy Spliet r.spliet@ultimaker.com
drivers/mtd/nand/Makefile | 2 +- drivers/mtd/nand/nand_timings.c | 252 ++++++++++++++++++++++++++++++++++++++++ include/linux/mtd/nand.h | 3 + 3 files changed, 256 insertions(+), 1 deletion(-) create mode 100644 drivers/mtd/nand/nand_timings.c
This code comes from Linux and yet I see no acknowledgement of that, much less a statement of which version of Linux this was pulled from.
Correct, my apologies as I should have clarified that "work by Boris Brezillon" does not mean "upsteam work". The code comes from Boris' github tree[1] and contains work that was not yet brought upstream, yet is required for NAND on sunxi to work.
It would probably be better to handle this as part of a general sync with the Linux mtd code.
Ideally yes, but. In upstream Linux MTD we have a few issues to address as shown by Boris' patch-set, most importantly:
- NAND chip timings (patch 1 to 3)
Patches 1-3 are already in Linux (if there are subtle differences needed those should be followup patches, with an explanation of why it needs to differ from Linux), except that patch 3 for some reason has "onfi_timing_mode_ds" where Linux has "onfi_timing_mode_default".
I will try to do a sync soon.
U-Boot has the additional challenge
- Partitioning is not done the upstream way, but rather in/around
cmd_mtdparts
We started discussion on these topics in the #mtd IRC channel (OFTC), and several ideas have come up. The way I see it these issues can currently either be addressed by bolting/duct-taping/tie-wrapping more layers of indirection on top of upstream MTD framework, but really I feel that it might require a bit more of a structural approach that may or may not break existing drivers. The code I posted as RFC is functional. If you wish to steer towards an MTD sync-up, I highly suggest first getting these issues tackled, and then making sure that we extend the U-boot side of MTD with OF support for everything. This trajectory should include deprecating the current implementation of cmd_mtdparts and hook that command up to the "new" upstream way. In other words: now is probably not the right moment.
I don't see why those things are a prerequisite for syncing MTD from Linux to U-Boot. If there are further changes in Linux after a sync that we want to bring in, we can sync again and it will be easier because the sync will contain fewer changes.
-Scott