[PATCH 0/8] Cleanup series about Hamming helpers

[PATCH 0/8] Cleanup series about Hamming helpers

[Miquel Raynal]

Hello,

The detailed description is available in each patch description but
basically:
* The FSMC driver was (I believe) still broken so here is a patch for
  that.
* As requested by Linus when he pulled a series of fixes during the 5.13
  cycle, the need for declaring individual indentical helpers in each
  driver using the "raw" Hamming ECC helpers was unjustified:
  - Here is a proposal for simplifying the situation
  - Followed by a series of revert (no need to backport these, it's just
    general cleanup).

Thanks,
Miquèl

Miquel Raynal (8):
  mtd: rawnand: fsmc: Fix use of SM ORDER
  mtd: rawnand: Let callers use the bare Hamming helpers
  Revert "mtd: rawnand: txx9ndfmc: Fix external use of SW Hamming ECC
    helper"
  Revert "mtd: rawnand: tmio: Fix external use of SW Hamming ECC helper"
  Revert "mtd: rawnand: sharpsl: Fix external use of SW Hamming ECC
    helper"
  Revert "mtd: rawnand: ndfc: Fix external use of SW Hamming ECC helper"
  Revert "mtd: rawnand: lpc32xx_slc: Fix external use of SW Hamming ECC
    helper"
  Revert "mtd: rawnand: cs553x: Fix external use of SW Hamming ECC
    helper"

 drivers/mtd/nand/ecc-sw-hamming.c  |  7 ++++---
 drivers/mtd/nand/raw/cs553x_nand.c | 12 +-----------
 drivers/mtd/nand/raw/fsmc_nand.c   |  4 +++-
 drivers/mtd/nand/raw/lpc32xx_slc.c | 15 +--------------
 drivers/mtd/nand/raw/ndfc.c        | 12 +-----------
 drivers/mtd/nand/raw/sharpsl.c     | 12 +-----------
 drivers/mtd/nand/raw/tmio_nand.c   |  8 +++-----
 drivers/mtd/nand/raw/txx9ndfmc.c   |  5 ++---
 8 files changed, 16 insertions(+), 59 deletions(-)

-- 
2.27.0

[PATCH 1/8] mtd: rawnand: fsmc: Fix use of SM ORDER

[Miquel Raynal]

The introduction of the generic ECC engine API lead to a number of
changes in various drivers which broke some of them. Here is a typical
example: I expected the SM_ORDER option to be handled by the Hamming ECC
engine internals. Problem: the fsmc driver does not instantiate (yet) a
real ECC engine object so we had to use a 'bare' ECC helper instead of
the shiny rawnand functions. However, when not intializing this engine
properly and using the bare helpers, we do not get the SM ORDER feature
handled automatically. It looks like this was lost in the process so
let's ensure we use the right SM ORDER now.

Fixes: ad9ffdce4539 ("mtd: rawnand: fsmc: Fix external use of SW Hamming ECC helper")
Cc: stable@vger.kernel.org
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/fsmc_nand.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/mtd/nand/raw/fsmc_nand.c b/drivers/mtd/nand/raw/fsmc_nand.c
index a3e66155ae40..658f0cbe7ce8 100644
--- a/drivers/mtd/nand/raw/fsmc_nand.c
+++ b/drivers/mtd/nand/raw/fsmc_nand.c
@@ -438,8 +438,10 @@ static int fsmc_correct_ecc1(struct nand_chip *chip,
 			     unsigned char *read_ecc,
 			     unsigned char *calc_ecc)
 {
+	bool sm_order = chip->ecc.options & NAND_ECC_SOFT_HAMMING_SM_ORDER;
+
 	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				      chip->ecc.size, false);
+				      chip->ecc.size, sm_order);
 }
 
 /* Count the number of 0's in buff upto a max of max_bits */
-- 
2.27.0

[PATCH 2/8] mtd: rawnand: Let callers use the bare Hamming helpers

[Miquel Raynal]

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

Enhancing the implementation of the rawnand_ecc_sw_* helpers to support
both cases, when the ECC object is instantiated and when it is not is a
quite elegant way to solve this situation. This way, we can still use
the existing and exported rawnand helpers while avoiding the need for
each driver to declare its own helper.

Following this change, most of the fixes sent in [2] can now be safely
reverted. Only the fsmc fix will need to be kept because there is
actually something specific to the driver to do in its ->correct()
helper.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com/

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/ecc-sw-hamming.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/ecc-sw-hamming.c b/drivers/mtd/nand/ecc-sw-hamming.c
index a7655b668f32..254db2e7f8bb 100644
--- a/drivers/mtd/nand/ecc-sw-hamming.c
+++ b/drivers/mtd/nand/ecc-sw-hamming.c
@@ -364,9 +364,9 @@ int nand_ecc_sw_hamming_calculate(struct nand_device *nand,
 {
 	struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv;
 	unsigned int step_size = nand->ecc.ctx.conf.step_size;
+	bool sm_order = engine_conf ? engine_conf->sm_order : false;
 
-	return ecc_sw_hamming_calculate(buf, step_size, code,
-					engine_conf->sm_order);
+	return ecc_sw_hamming_calculate(buf, step_size, code, sm_order);
 }
 EXPORT_SYMBOL(nand_ecc_sw_hamming_calculate);
 
@@ -457,9 +457,10 @@ int nand_ecc_sw_hamming_correct(struct nand_device *nand, unsigned char *buf,
 {
 	struct nand_ecc_sw_hamming_conf *engine_conf = nand->ecc.ctx.priv;
 	unsigned int step_size = nand->ecc.ctx.conf.step_size;
+	bool sm_order = engine_conf ? engine_conf->sm_order : false;
 
 	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc, step_size,
-				      engine_conf->sm_order);
+				      sm_order);
 }
 EXPORT_SYMBOL(nand_ecc_sw_hamming_correct);
 
-- 
2.27.0

[PATCH 3/8] Revert "mtd: rawnand: txx9ndfmc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit 3d227a0b0ce319edbff6fd0d8af4d66689e477cc.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/txx9ndfmc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/mtd/nand/raw/txx9ndfmc.c b/drivers/mtd/nand/raw/txx9ndfmc.c
index b8894ac27073..1a9449e53bf9 100644
--- a/drivers/mtd/nand/raw/txx9ndfmc.c
+++ b/drivers/mtd/nand/raw/txx9ndfmc.c
@@ -13,7 +13,6 @@
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/mtd/mtd.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/partitions.h>
 #include <linux/io.h>
@@ -194,8 +193,8 @@ static int txx9ndfmc_correct_data(struct nand_chip *chip, unsigned char *buf,
 	int stat;
 
 	for (eccsize = chip->ecc.size; eccsize > 0; eccsize -= 256) {
-		stat = ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-					      chip->ecc.size, false);
+		stat = rawnand_sw_hamming_correct(chip, buf, read_ecc,
+						  calc_ecc);
 		if (stat < 0)
 			return stat;
 		corrected += stat;
-- 
2.27.0

[PATCH 4/8] Revert "mtd: rawnand: tmio: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit 6a4c5ada577467a5f79e06f2c5e69c09983c22fb.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/tmio_nand.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/mtd/nand/raw/tmio_nand.c b/drivers/mtd/nand/raw/tmio_nand.c
index 6d93dd31969b..de8e919d0ebe 100644
--- a/drivers/mtd/nand/raw/tmio_nand.c
+++ b/drivers/mtd/nand/raw/tmio_nand.c
@@ -34,7 +34,6 @@
 #include <linux/interrupt.h>
 #include <linux/ioport.h>
 #include <linux/mtd/mtd.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/partitions.h>
 #include <linux/slab.h>
@@ -293,12 +292,11 @@ static int tmio_nand_correct_data(struct nand_chip *chip, unsigned char *buf,
 	int r0, r1;
 
 	/* assume ecc.size = 512 and ecc.bytes = 6 */
-	r0 = ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				    chip->ecc.size, false);
+	r0 = rawnand_sw_hamming_correct(chip, buf, read_ecc, calc_ecc);
 	if (r0 < 0)
 		return r0;
-	r1 = ecc_sw_hamming_correct(buf + 256, read_ecc + 3, calc_ecc + 3,
-				    chip->ecc.size, false);
+	r1 = rawnand_sw_hamming_correct(chip, buf + 256, read_ecc + 3,
+					calc_ecc + 3);
 	if (r1 < 0)
 		return r1;
 	return r0 + r1;
-- 
2.27.0

[PATCH 5/8] Revert "mtd: rawnand: sharpsl: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit 46fcb57e6b7283533ebf8ba17a6bd30fa88bdc9f.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/sharpsl.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/mtd/nand/raw/sharpsl.c b/drivers/mtd/nand/raw/sharpsl.c
index 2f1fe464e663..5612ee628425 100644
--- a/drivers/mtd/nand/raw/sharpsl.c
+++ b/drivers/mtd/nand/raw/sharpsl.c
@@ -11,7 +11,6 @@
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/mtd/mtd.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/partitions.h>
 #include <linux/mtd/sharpsl.h>
@@ -97,15 +96,6 @@ static int sharpsl_nand_calculate_ecc(struct nand_chip *chip,
 	return readb(sharpsl->io + ECCCNTR) != 0;
 }
 
-static int sharpsl_nand_correct_ecc(struct nand_chip *chip,
-				    unsigned char *buf,
-				    unsigned char *read_ecc,
-				    unsigned char *calc_ecc)
-{
-	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				      chip->ecc.size, false);
-}
-
 static int sharpsl_attach_chip(struct nand_chip *chip)
 {
 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
@@ -116,7 +106,7 @@ static int sharpsl_attach_chip(struct nand_chip *chip)
 	chip->ecc.strength = 1;
 	chip->ecc.hwctl = sharpsl_nand_enable_hwecc;
 	chip->ecc.calculate = sharpsl_nand_calculate_ecc;
-	chip->ecc.correct = sharpsl_nand_correct_ecc;
+	chip->ecc.correct = rawnand_sw_hamming_correct;
 
 	return 0;
 }
-- 
2.27.0

[PATCH 6/8] Revert "mtd: rawnand: ndfc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit 3e09c0252501829b14b10f14e1982aaab77d0b80.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/ndfc.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/mtd/nand/raw/ndfc.c b/drivers/mtd/nand/raw/ndfc.c
index 98d5a94c3a24..338d6b1a189e 100644
--- a/drivers/mtd/nand/raw/ndfc.c
+++ b/drivers/mtd/nand/raw/ndfc.c
@@ -22,7 +22,6 @@
 #include <linux/mtd/ndfc.h>
 #include <linux/slab.h>
 #include <linux/mtd/mtd.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <asm/io.h>
@@ -101,15 +100,6 @@ static int ndfc_calculate_ecc(struct nand_chip *chip,
 	return 0;
 }
 
-static int ndfc_correct_ecc(struct nand_chip *chip,
-			    unsigned char *buf,
-			    unsigned char *read_ecc,
-			    unsigned char *calc_ecc)
-{
-	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				      chip->ecc.size, false);
-}
-
 /*
  * Speedups for buffer read/write/verify
  *
@@ -155,7 +145,7 @@ static int ndfc_chip_init(struct ndfc_controller *ndfc,
 	chip->controller = &ndfc->ndfc_control;
 	chip->legacy.read_buf = ndfc_read_buf;
 	chip->legacy.write_buf = ndfc_write_buf;
-	chip->ecc.correct = ndfc_correct_ecc;
+	chip->ecc.correct = rawnand_sw_hamming_correct;
 	chip->ecc.hwctl = ndfc_enable_hwecc;
 	chip->ecc.calculate = ndfc_calculate_ecc;
 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
-- 
2.27.0

[PATCH 7/8] Revert "mtd: rawnand: lpc32xx_slc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit c4b7d7c480d607e4f52d310d9d16b194868d0917.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/lpc32xx_slc.c | 15 +--------------
 1 file changed, 1 insertion(+), 14 deletions(-)

diff --git a/drivers/mtd/nand/raw/lpc32xx_slc.c b/drivers/mtd/nand/raw/lpc32xx_slc.c
index d7dfc6fd85ca..6b7269cfb7d8 100644
--- a/drivers/mtd/nand/raw/lpc32xx_slc.c
+++ b/drivers/mtd/nand/raw/lpc32xx_slc.c
@@ -27,7 +27,6 @@
 #include <linux/of.h>
 #include <linux/of_gpio.h>
 #include <linux/mtd/lpc32xx_slc.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 
 #define LPC32XX_MODNAME		"lpc32xx-nand"
 
@@ -345,18 +344,6 @@ static int lpc32xx_nand_ecc_calculate(struct nand_chip *chip,
 	return 0;
 }
 
-/*
- * Corrects the data
- */
-static int lpc32xx_nand_ecc_correct(struct nand_chip *chip,
-				    unsigned char *buf,
-				    unsigned char *read_ecc,
-				    unsigned char *calc_ecc)
-{
-	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				      chip->ecc.size, false);
-}
-
 /*
  * Read a single byte from NAND device
  */
@@ -815,7 +802,7 @@ static int lpc32xx_nand_attach_chip(struct nand_chip *chip)
 	chip->ecc.write_oob = lpc32xx_nand_write_oob_syndrome;
 	chip->ecc.read_oob = lpc32xx_nand_read_oob_syndrome;
 	chip->ecc.calculate = lpc32xx_nand_ecc_calculate;
-	chip->ecc.correct = lpc32xx_nand_ecc_correct;
+	chip->ecc.correct = rawnand_sw_hamming_correct;
 	chip->ecc.hwctl = lpc32xx_nand_ecc_enable;
 
 	/*
-- 
2.27.0

[PATCH 8/8] Revert "mtd: rawnand: cs553x: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

This reverts commit 56a8d3fd1f342d10ee7b27e9ac0f4d00b5fbb91c.

Before the introduction of the ECC framework infrastructure, many
drivers used the ->calculate/correct() Hamming helpers directly. The
point of this framework was to avoid this kind of hackish calls and use a
proper and generic API but it is true that in certain cases, drivers
still need to use these helpers in order to do ECC computations on
behalf of their limited hardware.

Right after the introduction of the ECC engine core introduction, it was
spotted that it was not possible to use the shiny rawnand software ECC
helpers so easily because an ECC engine object should have been
allocated and initialized first. While this works well in most cases,
for these drivers just leveraging the power of a single helper in
conjunction with some pretty old and limited hardware, it did not fit.

The idea back then was to declare intermediate helpers which would make
use of the exported software ECC engine bare functions while keeping the
rawnand layer compatibility. As there was already functions with the
rawnand_sw_hamming_ prefix it was decided to declare new local helpers
for this purpose in each driver needing one.

Besides being far from optimal, this design choice was blamed by Linus
when he pulled the "fixes" pull request [1] so that is why now it is
time to clean this mess up.

The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
to support both cases, when the ECC object is instantiated and when it is
not. This way, we can still use the existing and exported rawnand
helpers while avoiding the need for each driver to declare its own
helper, thus this fix from [2] can now be safely reverted.

[1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
[2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/mtd/nand/raw/cs553x_nand.c | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/drivers/mtd/nand/raw/cs553x_nand.c b/drivers/mtd/nand/raw/cs553x_nand.c
index df40927e5678..6edf78c16fc8 100644
--- a/drivers/mtd/nand/raw/cs553x_nand.c
+++ b/drivers/mtd/nand/raw/cs553x_nand.c
@@ -18,7 +18,6 @@
 #include <linux/module.h>
 #include <linux/delay.h>
 #include <linux/mtd/mtd.h>
-#include <linux/mtd/nand-ecc-sw-hamming.h>
 #include <linux/mtd/rawnand.h>
 #include <linux/mtd/partitions.h>
 #include <linux/iopoll.h>
@@ -241,15 +240,6 @@ static int cs_calculate_ecc(struct nand_chip *this, const u_char *dat,
 	return 0;
 }
 
-static int cs553x_ecc_correct(struct nand_chip *chip,
-			      unsigned char *buf,
-			      unsigned char *read_ecc,
-			      unsigned char *calc_ecc)
-{
-	return ecc_sw_hamming_correct(buf, read_ecc, calc_ecc,
-				      chip->ecc.size, false);
-}
-
 static struct cs553x_nand_controller *controllers[4];
 
 static int cs553x_attach_chip(struct nand_chip *chip)
@@ -261,7 +251,7 @@ static int cs553x_attach_chip(struct nand_chip *chip)
 	chip->ecc.bytes = 3;
 	chip->ecc.hwctl  = cs_enable_hwecc;
 	chip->ecc.calculate = cs_calculate_ecc;
-	chip->ecc.correct  = cs553x_ecc_correct;
+	chip->ecc.correct  = rawnand_sw_hamming_correct;
 	chip->ecc.strength = 1;
 
 	return 0;
-- 
2.27.0

Re: [PATCH 8/8] Revert "mtd: rawnand: cs553x: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:07 UTC, Miquel Raynal wrote:
> This reverts commit 56a8d3fd1f342d10ee7b27e9ac0f4d00b5fbb91c.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 7/8] Revert "mtd: rawnand: lpc32xx_slc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:06 UTC, Miquel Raynal wrote:
> This reverts commit c4b7d7c480d607e4f52d310d9d16b194868d0917.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 6/8] Revert "mtd: rawnand: ndfc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:05 UTC, Miquel Raynal wrote:
> This reverts commit 3e09c0252501829b14b10f14e1982aaab77d0b80.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 5/8] Revert "mtd: rawnand: sharpsl: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:04 UTC, Miquel Raynal wrote:
> This reverts commit 46fcb57e6b7283533ebf8ba17a6bd30fa88bdc9f.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 4/8] Revert "mtd: rawnand: tmio: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:03 UTC, Miquel Raynal wrote:
> This reverts commit 6a4c5ada577467a5f79e06f2c5e69c09983c22fb.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 3/8] Revert "mtd: rawnand: txx9ndfmc: Fix external use of SW Hamming ECC helper"

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:02 UTC, Miquel Raynal wrote:
> This reverts commit 3d227a0b0ce319edbff6fd0d8af4d66689e477cc.
> 
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> The implementation of the rawnand_ecc_sw_* helpers has now been enhanced
> to support both cases, when the ECC object is instantiated and when it is
> not. This way, we can still use the existing and exported rawnand
> helpers while avoiding the need for each driver to declare its own
> helper, thus this fix from [2] can now be safely reverted.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 2/8] mtd: rawnand: Let callers use the bare Hamming helpers

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:01 UTC, Miquel Raynal wrote:
> Before the introduction of the ECC framework infrastructure, many
> drivers used the ->calculate/correct() Hamming helpers directly. The
> point of this framework was to avoid this kind of hackish calls and use a
> proper and generic API but it is true that in certain cases, drivers
> still need to use these helpers in order to do ECC computations on
> behalf of their limited hardware.
> 
> Right after the introduction of the ECC engine core introduction, it was
> spotted that it was not possible to use the shiny rawnand software ECC
> helpers so easily because an ECC engine object should have been
> allocated and initialized first. While this works well in most cases,
> for these drivers just leveraging the power of a single helper in
> conjunction with some pretty old and limited hardware, it did not fit.
> 
> The idea back then was to declare intermediate helpers which would make
> use of the exported software ECC engine bare functions while keeping the
> rawnand layer compatibility. As there was already functions with the
> rawnand_sw_hamming_ prefix it was decided to declare new local helpers
> for this purpose in each driver needing one.
> 
> Besides being far from optimal, this design choice was blamed by Linus
> when he pulled the "fixes" pull request [1] so that is why now it is
> time to clean this mess up.
> 
> Enhancing the implementation of the rawnand_ecc_sw_* helpers to support
> both cases, when the ECC object is instantiated and when it is not is a
> quite elegant way to solve this situation. This way, we can still use
> the existing and exported rawnand helpers while avoiding the need for
> each driver to declare its own helper.
> 
> Following this change, most of the fixes sent in [2] can now be safely
> reverted. Only the fsmc fix will need to be kept because there is
> actually something specific to the driver to do in its ->correct()
> helper.
> 
> [1] https://lore.kernel.org/lkml/CAHk-=wh_ZHF685Fni8V9is17mj=pFisUaZ_0=gq6nbK+ZcyQmg@mail.gmail.com/
> [2] https://lore.kernel.org/linux-mtd/20210413161840.345208-1-miquel.raynal@bootlin.com/
> 
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel

Re: [PATCH 1/8] mtd: rawnand: fsmc: Fix use of SM ORDER

[Miquel Raynal]

On Tue, 2021-09-28 at 22:15:00 UTC, Miquel Raynal wrote:
> The introduction of the generic ECC engine API lead to a number of
> changes in various drivers which broke some of them. Here is a typical
> example: I expected the SM_ORDER option to be handled by the Hamming ECC
> engine internals. Problem: the fsmc driver does not instantiate (yet) a
> real ECC engine object so we had to use a 'bare' ECC helper instead of
> the shiny rawnand functions. However, when not intializing this engine
> properly and using the bare helpers, we do not get the SM ORDER feature
> handled automatically. It looks like this was lost in the process so
> let's ensure we use the right SM ORDER now.
> 
> Fixes: ad9ffdce4539 ("mtd: rawnand: fsmc: Fix external use of SW Hamming ECC helper")
> Cc: stable@vger.kernel.org
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git nand/next.

Miquel