Hi Francesco,
francesco@dolcini.it wrote on Fri, 2 Dec 2022 08:19:00 +0100:
From: Francesco Dolcini francesco.dolcini@toradex.com
Add a fallback mechanism to handle the case in which #size-cells is set to <0>. According to the DT binding the nand controller node should have set it to 0 and this is not compatible with the legacy way of specifying partitions directly as child nodes of the nand-controller node.
I understand the problem, I understand the fix, but I have to say, I strongly dislike it :) Touching an mtd core driver to fix a single broken use case like that is... problematic, for the least.
I am sorry but if a 6.0 kernel breaks because: - a legacy scheme is used in the description - u-boot still does not conform to the DT standard - a patch tries to make a tool happy Then the solution is clearly not an 'mtd core' mainline patch.
If you really want to workaround U-Boot, either you revert that patch or you just fix the DT description instead. The parent/child/partitions scheme has been enforced for maybe 5 years now and for a good reason: a NAND controller with partitions does not make _any_ sense. There are plenty of examples out there, imx7-colibri.dtsi has received many updates since its introduction (for the best), so why not this one?
Cheers, Miquèl
This fixes a boot failure on colibri-imx7 and potentially other boards.
Cc: stable@vger.kernel.org Fixes: 753395ea1e45 ("ARM: dts: imx7: Fix NAND controller size-cells") Link: https://lore.kernel.org/all/Y4dgBTGNWpM6SQXI@francesco-nb.int.toradex.com/ Signed-off-by: Francesco Dolcini francesco.dolcini@toradex.com
drivers/mtd/parsers/ofpart_core.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/drivers/mtd/parsers/ofpart_core.c b/drivers/mtd/parsers/ofpart_core.c index 192190c42fc8..aa3b7fa61e50 100644 --- a/drivers/mtd/parsers/ofpart_core.c +++ b/drivers/mtd/parsers/ofpart_core.c @@ -122,6 +122,17 @@ static int parse_fixed_partitions(struct mtd_info *master, a_cells = of_n_addr_cells(pp); s_cells = of_n_size_cells(pp);
if (s_cells == 0) {/** Use #size-cells = <1> for backward compatibility* in case #size-cells is set to <0> and firmware adds* OF partitions without setting it.*/pr_warn_once("%s: ofpart partition %pOF (%pOF) #size-cells is <0>, using <1> for backward compatibility.\n",master->name, pp,mtd_node);s_cells = 1;}