Implementing the mtd_ooblayout_ops interface is the new way of exposing
ECC/OOB layout to MTD users.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Replace the nand_ecclayout definition by the equivalent mtd_ooblayout_ops
definition.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Replace the default nand_ecclayout definitions for large and small page
devices with the equivalent mtd_ooblayout_ops.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Replace the nand_ecclayout definition by the equivalent mtd_ooblayout_ops
definition.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>

ECC layout definitions are currently exposed using the nand_ecclayout
struct which embeds oobfree and eccpos arrays with predefined size.
This approach was acceptable when NAND chips were providing relatively
small OOB regions, but MLC and TLC now provide OOB regions of several
hundreds of bytes, which implies a non negligible overhead for everybody
even those who only need to support legacy NANDs.

Create an mtd_ooblayout_ops interface providing the same functionality
(expose the ECC and oobfree layout) without the need for this huge
structure.

The mtd->ecclayout is now deprecated and should be replaced by the
equivalent mtd_ooblayout_ops. In the meantime we provide a wrapper around
the ->ecclayout field to ease migration to this new model.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>

Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Use the mtd_set_ecclayout() helper instead of directly assigning the
mtd->ecclayout field.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Add an mtd_set_ecclayout() helper function to avoid direct accesses to the
mtd->ecclayout field. This will ease future reworks of ECC layout
definition.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to ecclayout fields, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Tested-by: Archit Taneja <architt@codeaurora.org>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The mtd_ooblayout_xxx() helper functions have been added to avoid direct
accesses to the ecclayout field, and thus ease for future reworks.
Use these helpers in all places where the oobfree[] and eccpos[] arrays
where directly accessed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

In order to make the ecclayout definition completely dynamic we need to
rework the way the OOB layout are defined and iterated.

Create a few mtd_ooblayout_xxx() helpers to ease OOB bytes manipulation
and hide ecclayout internals to their users.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Allow for NULL cur_offs values when the caller does not know where the
NAND page register pointer points to.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

sunxi_nfc_hw_ecc_read_chunk() always retrieves the ECC and protected free
bytes, no matter if the user really asked for it or not. This can take a
non negligible amount of time, especially on NAND chips exposing large OOB
areas (> 1KB). Make it optional.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

In order to support DMA operations in a clean way we need to extract some
of the logic coded in sunxi_nfc_hw_ecc_read/write_page() into their own
function.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Some NAND operations are so fast that it doesn't make any sense to use
interrupt based waits (the scheduling overhead is not worth it).
Rename sunxi_nfc_wait_int() into sunxi_nfc_wait_events() and add a
parameter to specify whether polling should be used or not.

Note that all sunxi_nfc_wait_int() are moved to the polling approach now,
but this should change as soon as we have more information about the
approximate time we are about to wait (can be extracted from the NAND
timings, and the type of operation).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Replace open coded polling loops by readl_poll_timeout() calls.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

->dev_ready() is not supposed to wait for busy to ready solution (this is
the role of ->waitfunc()).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

When the NAND controller operates in DMA mode it can pipeline ECC
operations which improves the throughput.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

mod and ahb clocks are not disabled when the NAND controller device is
removed.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

NFC_PAGE_SHIFT() already takes the real page_shift value and subtract 10
to it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

NFC_ECC_ERR_CNT() is not taking into account the case when the NAND chip
contains more than 4 ECC blocks (NANDs with 4kB+ pages).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

We don't need to manually toggle the CE line since the controller handles
it for us. Moreover, keeping the CE line low when interacting with a DDR
NAND can be problematic (data loss in some corner cases).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Try to pack address and command cycles into a single NAND controller
command to avoid polling the status register for each single change
on the NAND bus.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Being able to read subpages can greatly improve read performances if the
MTD user is only interested in a small section of a NAND page.
This is particularly true with large pages (>= 8k).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Allwinner's ECC engine is capable of protecting a few bytes of the OOB
area. Implement specific OOB functions to benefit from this capability.

Also, when in raw mode, the randomizer is disabled, which means you'll
only be able to retrieve randomized data, which is not really useful
for most applications.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Export the default read/write oob functions (for the standard and syndrome
scheme), so that drivers can use them for their raw implementation and
implement their own functions for the normal oob operation.

This is required if your ECC engine is capable of fixing some of the OOB
data. In this case you have to overload the ->read_oob() and ->write_oob(),
but if you don't specify the ->read/write_oob_raw() functions they are
assigned to the ->read/write_oob() implementation, which is not what you
want.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Adapt the NAND controller clk rate to the tWB, tADL, tWHR and tRHW
timings instead of returning an error when the maximum clk divisor is
not big enough to provide an appropriate timing.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The ONFI spec says that EDO should be enabled if the host drives tRC less
than 30ns, but the code just tests for the tRC_min value extracted from
the timings exposed by the NAND chip not the timings actually configured
in the NAND controller.
Fix that by first rounding down the requested clk_rate with
clk_round_rate() and then checking if tRC is actually smaller than 30ns.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

Unlike what is specified in the Allwinner datasheets, the NAND clock rate
is not equal to 2/T but 1/T. Fix the clock rate selection accordingly.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

sunxi_nand_chip_set_timings() is extracting a pointer to the nfc from the
nand->controller field, but this field is initialized after
sunxi_nand_chip_set_timings() call.
Reorder the calls to avoid any problem.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

The core now takes care of parsing generic DT properties in
nand_scan_ident() when nand_set_flash_node() has been called.
Rely on this initialization instead of calling of_get_nand_xxx()
manually.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>