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@@ -1,58 +0,0 @@
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-From 540dcef6f39d6356d2a65230a8d4e9738ee2d25b Mon Sep 17 00:00:00 2001
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-From: Christian Marangi <[email protected]>
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-Date: Wed, 20 Mar 2024 16:43:01 +0100
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-Subject: [PATCH] mtd: limit OTP nvmem to non nand devices
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-
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-MTD OTP logic is very fragile and can be problematic with some specific
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-kind of devices.
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-
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-NVMEM across the years had various iteration on how Cells could be
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-declared in DT and MTD OTP probably was left behind and
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-add_legacy_fixed_of_cells was enabled without thinking of the consequences.
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-
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-That option enables NVMEM to scan the provided of_node and treat each
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-child as a NVMEM Cell, this was to support legacy NVMEM implementation
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-and don't cause regression.
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-
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-This is problematic if we have devices like Nand where the OTP is
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-triggered by setting a special mode in the flash. In this context real
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-partitions declared in the Nand node are registered as OTP Cells and
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-this cause probe fail with -EINVAL error.
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-
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-This was never notice due to the fact that till now, no Nand supported
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-the OTP feature. With commit e87161321a40 ("mtd: rawnand: macronix: OTP
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-access for MX30LFxG18AC") this changed and coincidentally this Nand is
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-used on an FritzBox 7530 supported on OpenWrt.
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-
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-Alternative and more robust way to declare OTP Cells are already
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-prossible by using the fixed-layout node or by declaring a child node
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-with the compatible set to "otp-user" or "otp-factory".
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-
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-To fix this and limit any regression with other MTD that makes use of
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-declaring OTP as direct child of the dev node, disable
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-add_legacy_fixed_of_cells if we have a node called nand since it's the
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-standard property name to identify Nand devices attached to a Nand
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-Controller.
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-
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-With the following logic, the OTP NVMEM entry is correctly created with
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-no Cells and the MTD Nand is correctly probed and partitions are
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-correctly exposed.
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-
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-Fixes: 2cc3b37f5b6d ("nvmem: add explicit config option to read old syntax fixed OF cells")
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-Cc: <[email protected]>
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-Signed-off-by: Christian Marangi <[email protected]>
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----
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- drivers/mtd/mtdcore.c | 2 +-
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- 1 file changed, 1 insertion(+), 1 deletion(-)
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-
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---- a/drivers/mtd/mtdcore.c
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-+++ b/drivers/mtd/mtdcore.c
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-@@ -933,7 +933,7 @@ static struct nvmem_device *mtd_otp_nvme
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- config.name = compatible;
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- config.id = NVMEM_DEVID_AUTO;
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- config.owner = THIS_MODULE;
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-- config.add_legacy_fixed_of_cells = true;
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-+ config.add_legacy_fixed_of_cells = !of_node_name_eq(mtd->dev.of_node, "nand");
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- config.type = NVMEM_TYPE_OTP;
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- config.root_only = true;
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- config.ignore_wp = true;
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Mieczyslaw Nalewaj