Re: [PATCH 1/2] dt-bindings: mtd: nand: Macronix: document new binding

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Álvaro,

noltari@gmail.com wrote on Fri, 24 Mar 2023 18:04:38 +0100:

> Hi Miquèl,
> 
> 2023-03-24 15:36 GMT+01:00, Miquel Raynal <miquel.raynal@bootlin.com>:
> > Hi Álvaro,
> >
> > + YouChing and Jaime from Macronix
> > TLDR for them: there is a misbehavior since Mason added block
> > protection support. Just checking if the blocks are protected seems to
> > misconfigure the chip entirely, see below. Any hints?  
> 
> Could it be that the NAND is stuck expecting a read 0x00 command which
> isn’t sent after getting the features?

I have no idea, please try that, you can manually generate a READ0 by
hacking an existing read helper.

> > noltari@gmail.com wrote on Fri, 24 Mar 2023 15:15:47 +0100:
> >  
> >> Hi Miquèl,
> >>
> >> 2023-03-24 14:45 GMT+01:00, Miquel Raynal <miquel.raynal@bootlin.com>:  
> >> > Hi Álvaro,
> >> >
> >> > noltari@gmail.com wrote on Fri, 24 Mar 2023 12:21:11 +0100:
> >> >  
> >> >> El vie, 24 mar 2023 a las 11:49, Miquel Raynal
> >> >> (<miquel.raynal@bootlin.com>) escribió:  
> >> >> >
> >> >> > Hi Álvaro,
> >> >> >
> >> >> > noltari@gmail.com wrote on Fri, 24 Mar 2023 11:31:17 +0100:
> >> >> >  
> >> >> > > Hi Miquèl,
> >> >> > >
> >> >> > > El vie, 24 mar 2023 a las 10:40, Miquel Raynal
> >> >> > > (<miquel.raynal@bootlin.com>) escribió:  
> >> >> > > >
> >> >> > > > Hi Álvaro,
> >> >> > > >
> >> >> > > > noltari@gmail.com wrote on Thu, 23 Mar 2023 13:45:09 +0100:
> >> >> > > >  
> >> >> > > > > Add new "mxic,disable-block-protection" binding documentation.
> >> >> > > > > This binding allows disabling block protection support for
> >> >> > > > > those
> >> >> > > > > devices not
> >> >> > > > > supporting it.
> >> >> > > > >
> >> >> > > > > Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
> >> >> > > > > ---
> >> >> > > > >  Documentation/devicetree/bindings/mtd/nand-macronix.txt | 3
> >> >> > > > > +++
> >> >> > > > >  1 file changed, 3 insertions(+)
> >> >> > > > >
> >> >> > > > > diff --git
> >> >> > > > > a/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> >> >> > > > > b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> >> >> > > > > index ffab28a2c4d1..03f65ca32cd3 100644
> >> >> > > > > --- a/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> >> >> > > > > +++ b/Documentation/devicetree/bindings/mtd/nand-macronix.txt
> >> >> > > > > @@ -16,6 +16,9 @@ in children nodes.
> >> >> > > > >  Required NAND chip properties in children mode:
> >> >> > > > >  - randomizer enable: should be "mxic,enable-randomizer-otp"
> >> >> > > > >
> >> >> > > > > +Optional NAND chip properties in children mode:
> >> >> > > > > +- block protection disable: should be
> >> >> > > > > "mxic,disable-block-protection"
> >> >> > > > > +  
> >> >> > > >
> >> >> > > > Besides the fact that nowadays we prefer to see binding
> >> >> > > > conversions
> >> >> > > > to
> >> >> > > > yaml before adding anything, I don't think this will fly.
> >> >> > > >
> >> >> > > > I'm not sure exactly what "disable block protection" means, we
> >> >> > > > already have similar properties like "lock" and
> >> >> > > > "secure-regions",
> >> >> > > > not
> >> >> > > > sure they will fit but I think it's worth checking.  
> >> >> > >
> >> >> > > As explained in 2/2, commit 03a539c7a118 introduced a regression
> >> >> > > on
> >> >> > > Sercomm H500-s (BCM63268) OpenWrt devices with Macronix
> >> >> > > MX30LF1G18AC
> >> >> > > which hangs the device.
> >> >> > >
> >> >> > > This is the log with block protection disabled:
> >> >> > > [    0.495831] bcm6368_nand 10000200.nand: there is not valid maps
> >> >> > > for
> >> >> > > state default
> >> >> > > [    0.504995] nand: device found, Manufacturer ID: 0xc2, Chip ID:
> >> >> > > 0xf1
> >> >> > > [    0.511526] nand: Macronix MX30LF1G18AC
> >> >> > > [    0.515586] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
> >> >> > > 2048, OOB size: 64
> >> >> > > [    0.523516] bcm6368_nand 10000200.nand: detected 128MiB total,
> >> >> > > 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
> >> >> > > [    0.535912] Bad block table found at page 65472, version 0x01
> >> >> > > [    0.544268] Bad block table found at page 65408, version 0x01
> >> >> > > [    0.954329] 9 fixed-partitions partitions found on MTD device
> >> >> > > brcmnand.0
> >> >> > > ...
> >> >> > >
> >> >> > > This is the log with block protection enabled:
> >> >> > > [    0.495095] bcm6368_nand 10000200.nand: there is not valid maps
> >> >> > > for
> >> >> > > state default
> >> >> > > [    0.504249] nand: device found, Manufacturer ID: 0xc2, Chip ID:
> >> >> > > 0xf1
> >> >> > > [    0.510772] nand: Macronix MX30LF1G18AC
> >> >> > > [    0.514874] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
> >> >> > > 2048, OOB size: 64
> >> >> > > [    0.522780] bcm6368_nand 10000200.nand: detected 128MiB total,
> >> >> > > 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
> >> >> > > [    0.539687] Bad block table not found for chip 0
> >> >> > > [    0.550153] Bad block table not found for chip 0
> >> >> > > [    0.555069] Scanning device for bad blocks
> >> >> > > [    0.601213] CPU 1 Unable to handle kernel paging request at
> >> >> > > virtual
> >> >> > > address 10277f00, epc == 8039ce70, ra == 8016ad50
> >> >> > > *** Device hangs ***
> >> >> > >
> >> >> > > Enabling macronix_nand_block_protection_support() makes the device
> >> >> > > unable to detect the bad block table and hangs it when trying to
> >> >> > > scan
> >> >> > > for bad blocks.  
> >> >> >
> >> >> > Please trace nand_macronix.c and look:
> >> >> > - are the get_features and set_features really supported by the
> >> >> >   controller driver?  
> >> >>
> >> >> This is what I could find by debugging:
> >> >> [    0.494993] bcm6368_nand 10000200.nand: there is not valid maps for
> >> >> state default
> >> >> [    0.505375] nand: device found, Manufacturer ID: 0xc2, Chip ID:
> >> >> 0xf1
> >> >> [    0.512077] nand: Macronix MX30LF1G18AC
> >> >> [    0.515994] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
> >> >> 2048, OOB size: 64
> >> >> [    0.523928] bcm6368_nand 10000200.nand: detected 128MiB total,
> >> >> 128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-4
> >> >> [    0.534415] bcm6368_nand 10000200.nand: ll_op cmd 0xa00ee
> >> >> [    0.539988] bcm6368_nand 10000200.nand: ll_op cmd 0x600a0
> >> >> [    0.545659] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
> >> >> [    0.551214] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
> >> >> 0x00
> >> >> [    0.557843] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
> >> >> [    0.563475] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
> >> >> 0x00
> >> >> [    0.569998] bcm6368_nand 10000200.nand: ll_op cmd 0x10000
> >> >> [    0.575653] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
> >> >> 0x00
> >> >> [    0.582246] bcm6368_nand 10000200.nand: ll_op cmd 0x80010000
> >> >> [    0.588067] bcm6368_nand 10000200.nand: NAND_CMD_GET_FEATURES =
> >> >> 0x00
> >> >> [    0.594657] nand: nand_get_features: addr=a0 subfeature_param=[00
> >> >> 00 00 00] -> 0
> >> >> [    0.602341] macronix_nand_block_protection_support:
> >> >> ONFI_FEATURE_ADDR_MXIC_PROTECTION=0
> >> >> [    0.610548] macronix_nand_block_protection_support: !=
> >> >> MXIC_BLOCK_PROTECTION_ALL_LOCK
> >> >> [    0.624760] Bad block table not found for chip 0
> >> >> [    0.635542] Bad block table not found for chip 0
> >> >> [    0.640270] Scanning device for bad blocks
> >> >>
> >> >> I don't know how to tell if get_features / set_features is really
> >> >> supported...  
> >> >
> >> > Looks like your driver does not support exec_op but the core provides a
> >> > get/set_feature implementation.  
> >>
> >> According to Florian, low level should be supported on brcmnand
> >> controllers >= 4.0
> >> Also:
> >> https://github.com/nomis/bcm963xx_4.12L.06B_consumer/blob/e2f23ddbb20bf75689372b6e6a5a0dc613f6e313/shared/opensource/include/bcm963xx/63268_map_part.h#L1597  
> >
> > Just to be sure, you're using a mainline controller driver, not this
> > one?  
> 
> Yes, this was just to prove that the HW I’m using has get/set features support.
> I’m using OpenWrt, so it’s linux v5.15 driver.

Ok, thanks for the confirmation.

> 
> >  
> >> >  
> >> >>  
> >> >> > - what is the state of the locking configuration in the chip when
> >> >> > you
> >> >> >   boot?  
> >> >>
> >> >> Unlocked, I guess...
> >> >> How can I check that?  
> >> >
> >> > It's in your dump, the chip returns 0, meaning it's all unlocked,
> >> > apparently.  
> >>
> >> Well, I can read/write the device if block protection isn’t disabled,
> >> so I guess we can confirm it’s unlocked…
> >>  
> >> >  
> >> >> > - is there anything that locks the device by calling mxic_nand_lock()
> >> >> > ?  
> >> >
> >> > So nobody locks the device I guess? Did you add traces there?  
> >>
> >> It doesn’t get to the point that it enabled the lock/unlock functions
> >> since it fails when checking if feature is 0x38, so there’s no point
> >> in adding those traces…  
> >
> > Right, it returns before setting these I guess.
> >  
> >>  
> >> >  
> >> >> > - finding no bbt is one thing, hanging is another, where is it
> >> >> > hanging
> >> >> >   exactly? (offset in nand/ and line in the code)  
> >> >>
> >> >> I've got no idea...  
> >> >
> >> > You can use ftrace or just add printks a bit everywhere and try to get
> >> > closer and closer.  
> >>
> >> I think that after trying to get the feature it just start reading
> >> nonsense from the NAND and at some point it hangs due to that garbage…  
> >
> > It should refuse to mount the device somehow, but in no case the kernel
> > should hang.  
> 
> Yes, I think that this is a side effect (maybe a different bug somewhere else).

Could be worth checking.

> 
> >  
> >> Is it posible that the NAND starts behaving like this after getting
> >> the feature due to some specific config of my device?
> >>  
> >> >
> >> > I looked at the patch, I don't see anything strange. Besides, I have a
> >> > close enough datasheet and I don't see what could confuse the device.
> >> >
> >> > Are you really sure this patch is the problem? Is the WP pin wired on
> >> > your design?  
> >>
> >> There’s no WP pin in brcmnand controllers < 7.0  
> >
> > What about the chip?  
> 
> Maybe it has a GPIO controlling that, but I don’t have that info…

I mean, on the board, is the chip connected to some kind of
pull-up/down resistor? Because it may change its behavior.

Regarding your issue, I see there is a problem, but I don't get why.
The current proposal is not satisfying, I cannot pick this up. We
need feedback from Macronix :-)

Thanks,
Miquèl

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