Hi Francesco, [email protected] wrote on Fri, 13 Jan 2023 19:45:56 +0100:
> From: Francesco Dolcini <[email protected]> > > Add a mechanism to handle the case in which partitions are present as > direct child of the nand controller node and #size-cells is set to <0>. > > This could happen if the nand-controller node in the DTS is supposed to > have #size-cells set to 0, but for some historical reason/bug it was set > to 1 in the past, and the firmware (e.g. U-Boot) is adding the partition > as direct children of the nand-controller defaulting to #size-cells > being to 1. > > This prevents a real boot failure on colibri-imx7 that happened during v6.1 > development cycles. > > Link: > https://lore.kernel.org/all/[email protected]/ > Link: > https://lore.kernel.org/all/[email protected]/ > Signed-off-by: Francesco Dolcini <[email protected]> > Reviewed-by: Greg Kroah-Hartman <[email protected]> > --- > > Miquel, Marek: I do not expect this patch to be backported to stable, however > I would expect that we do not backport nand-controller dts cleanups neither. Okay. > > v2: > fixup size-cells only when partitions are direct children of the > nand-controller > completely revised commit message, comments and warning print > use pr_warn instead of pr_warn_once > added Reviewed-by Greg > removed cc:stable@ and fixes tag, since the problematic commit was reverted > --- > drivers/mtd/parsers/ofpart_core.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/mtd/parsers/ofpart_core.c > b/drivers/mtd/parsers/ofpart_core.c > index 192190c42fc8..46559a9248e6 100644 > --- a/drivers/mtd/parsers/ofpart_core.c > +++ b/drivers/mtd/parsers/ofpart_core.c > @@ -122,6 +122,26 @@ static int parse_fixed_partitions(struct mtd_info > *master, > > a_cells = of_n_addr_cells(pp); > s_cells = of_n_size_cells(pp); > + if (!dedicated && s_cells == 0) { > + /* > + * This is a hugly workaround to not create > + * regression on devices that are still creating > + * partitions as direct child of the nand controller. > + * This can happen in case the nand controller node has > + * #size-cells equal to 0 and the firmware (e.g. > + * U-Boot) just add the partitions there assuming > + * 32-bit addressing. > + * > + * If you get this warning your firmware and/or DTS > + * should be really fixed. > + * > + * This is working only for devices smaller than 4GiB. > + */ > + pr_warn("%s: ofpart partition %pOF (%pOF) #size-cells > is wrongly set to <0>, assuming <1> for parsing partitions.\n", > + master->name, pp, > + mtd_node); Why mtd_node on a new line? Otherwise looks good to me. > + s_cells = 1; > + } > if (len / 4 != a_cells + s_cells) { > pr_debug("%s: ofpart partition %pOF (%pOF) error > parsing reg property.\n", > master->name, pp, Thanks, Miquèl
