Messages in this thread | | | Date | Thu, 11 May 2023 12:17:31 +0300 | Subject | Re: [PATCH v3 6/6] mtd: rawnand: meson: rename node for chip select | From | Arseniy Krasnov <> |
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On 11.05.2023 12:12, Miquel Raynal wrote: > Hi Arseniy, > > avkrasnov@sberdevices.ru wrote on Thu, 11 May 2023 11:59:07 +0300: > >> On 10.05.2023 23:53, Miquel Raynal wrote: >> >> Hello Martin, Miquel >> >>> Hi Martin & Arseniy, >>> >>> martin.blumenstingl@googlemail.com wrote on Wed, 10 May 2023 22:40:37 >>> +0200: >>> >>>> Hello Arseniy, >>>> >>>> On Wed, May 10, 2023 at 1:13 PM Arseniy Krasnov >>>> <AVKrasnov@sberdevices.ru> wrote: >>>>> >>>>> This renames node with values for chip select from "reg" to "cs". It is >>>>> needed because when OTP access is enabled on the attached storage, MTD >>>>> subsystem registers this storage in the NVMEM subsystem. NVMEM in turn >>>>> tries to use "reg" node in its own manner, supposes that it has another >>>>> layout. All of this leads to device initialization failure. >>>> In general: if we change the device-tree interface (in this case: >>>> replacing a "reg" with a "cs" property) the dt-bindings have to be >>>> updated as well. >>> >>> True, and I would add, bindings should not be broken. >> >> I see, that's true. That is bad way to change bindings. >> >>> >>>> Documentation/devicetree/bindings/mtd/nand-controller.yaml and >>>> Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml show >>>> that the chip select of a NAND chip is specified with a "reg" >>>> property. >>> >>> All NAND controller binding expect the chip-select to be in the >>> 'reg' property, very much like a spi device would use reg to store the >>> cs as well: the reg property tells you how you address the device. >>> >>> I also fully agree with Martin's comments below. Changing reg is likely >>> a wrong approach :) >>> >>>> Also the code has to be backwards compatible with old .dtbs. >>>> >>>>> Example: >>>>> >>>>> [...] nvmem mtd0-user-otp: nvmem: invalid reg on /soc/bus@ffe00000/... >>>>> [...] mtd mtd0: Failed to register OTP NVMEM device >>>>> [...] meson-nand ffe07800.nfc: failed to register MTD device: -22 >>>>> [...] meson-nand ffe07800.nfc: failed to init NAND chips >>>>> [...] meson-nand: probe of ffe07800.nfc failed with error -22 >>>> This is odd - can you please share your definition of the &nfc node? >> >> Sure, here it is: >> >> mtd_nand: nfc@7800 { >> compatible = "amlogic,meson-axg-nfc"; >> ... >> nand@0 { >> reg = <0>; >> }; >> } >> >> I checked, that 'nand_set_flash_node()' is called with 'nand@0' and i suppose >> that it is correct (as You mentioned below). But, 'nvmem_add_cells_from_of()' is called >> with parent: 'nfc@7800', then it iterates over its childs, e.g. 'nand@0' and thus i get such >> situation. I guess, that 'nvmem_add_cells_from_of()' must be called with 'nand@0' ? > > We recently had issues with nvmem parsing, but I believe a mainline > kernel should now be perfectly working on this regard. What version of > the Linux kernel are you using?
My current version is:
VERSION = 6 PATCHLEVEL = 2 SUBLEVEL = 0 EXTRAVERSION = -rc8
Fix was in drivers/nvmem/* ?
Thanks, Arseniy
> > Thanks, > Miquèl
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