Message-ID: <20180712173235.7901-1-tudor.ambarus@microchip.com>
Date:   Thu, 12 Jul 2018 20:32:32 +0300
From:   Tudor Ambarus <tudor.ambarus@...rochip.com>
To:     <marek.vasut@...il.com>, <cyrille.pitchen@...rochip.com>,
        <dwmw2@...radead.org>, <computersforpeace@...il.com>,
        <boris.brezillon@...tlin.com>, <richard@....at>
CC:     <linux-mtd@...ts.infradead.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <nicolas.ferre@...rochip.com>,
        <Cristian.Birsan@...rochip.com>,
        Tudor Ambarus <tudor.ambarus@...rochip.com>
Subject: [PATCH v2 0/3] add support to non-uniform SFDP SPI NOR flash memories

Backward compatibility test done on mx25l3273fm2i-08g.
Non-uniform erase test done on sst26vf064b-104i/sn.

Note that in order to do the non-uniform test on the aforementioned memory
you'll have to force the spi_nor_has_uniform_erase() to return false, because
the erase map is tuned to come back to the uniform case. Also, you'll have to
unlock the global protection on the flash. There was an attempt to unlock this
protection, but for whatever reason the patch was not taken:
https://patchwork.ozlabs.org/patch/544270/. I'm taking care of the
global protection lock on sst26vf064b-104i/sn, I will submit a patch soon.

Changes in v2:
- add JESD216B SFDP optional parser: Sector Map Parameter Table parser
  and 4-byte Address Instruction Table parser (patch 2/3 and patch 3/3).
- fix condition on finding erase regions
- fix the list command adding
- write_enable(nor); before erasing the sectors
- As Boris suggested, remove likely() because it doesn't make any difference
  given the time it takes to actually erase the block.
- save the Erase Types from bfpt, to determine the Erase Type sizes. Sort all
  the map's Erase Types in ascending order with the smallest erase size being
  the first member in the erase_type array. Sort Erase Type mask in regions.
  We sort the Erase Type by size, at init, in order to speed up the
  process of finding the best erase command at run-time.
- spi_nor_select_erase(): pass directly info->sector_size instead of the whole
  flash_info structure in order to simplify the code.
- keep the same convention as most flashes, and order erase types by size with
  the smallest Erase Type size starting at index 0/ BIT(0).
- return unused function: spi_nor_region_mark_end().
- fix return value of spi_nor_has_uniform_erase().
- remove setting of mtd->erasesize and nor->erase_opcode when parsing the Basic
  Flash Parameter Table. mtd->erasesize was set to the maximum supported Erase
  Type size, without verifying if that Erase Type can erase the entire flash.
  mtd->erasesize is now set just in spi_nor_select_erase(), after we find which
  Erase Types are supported in the uniform case.

Changes in v1 or what I've done on top of Cyrille's work (https://lkml.org/lkml/2017/4/15/70):
- minimize the amount of erase() calls by using the best sequence of erase
  type commands depending on alignment.
- build the list of best fitted erase commands to be executed once we
  validate that the erase can be performed.
- add improvements on how the erase map is handled. The regions are
  consecutive in the address space, walk through the regions incrementally.
- speed up finding the best erase type command. Order erase types by
  size, iterate them from the biggest to the smallest and stop when best
  fitted command is found.
- determine at init if there are erase types that can erase the entire
  memory
- fix support for overlaid regions.

Cyrille Pitchen (1):
  mtd: spi-nor: parse SFDP 4-byte Address Instruction Table

Tudor Ambarus (2):
  mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories
  mtd: spi-nor: parse SFDP Sector Map Parameter Table

 drivers/mtd/spi-nor/spi-nor.c | 892 +++++++++++++++++++++++++++++++++++++++---
 include/linux/mtd/spi-nor.h   | 120 ++++++
 2 files changed, 954 insertions(+), 58 deletions(-)

-- 
2.9.4

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