[PATCH v6 0/3] spi-nor: Add support for Intel SPI serial flash controller

[Mika Westerberg]

This is 6th iteration of the series. You can find the previous versions
archived on:

  v5: https://lwn.net/Articles/706363/
  v4: https://lwn.net/Articles/703773/
  v3: https://lwn.net/Articles/697231/
  v2: http://lists.infradead.org/pipermail/linux-mtd/2016-June/068277.html
  v1: https://lkml.org/lkml/2016/6/14/269

This patch series adds support for the Intel SPI serial flash controller
found on many recent Intel CPUs including Baytrail and Braswell. This
driver makes it possible to access the BIOS and other platform data which
is stored on the SPI serial flash. It is also possible to upgrade the BIOS
using this driver if it has not been protected by special hardware bits.

The patch [1/3] includes documentation how to upgrade BIOS on MinnowBoard
MAX.

Since poking the SPI serial flash can brick the machine, this driver can
only be enabled when CONFIG_EXPERT=y and even then it will remain read-only
unless instructed othwerwise by module parameter.

Changes from v5:
  * Use readl_poll_timeout() from iopoll.h instead of open-coding busy
    waiting.
  * First clear bits and then set them in intel_spi_read() and
    intel_spi_write().
  * Use round_down() in lpc_ich_init_spi().
  * Add ACKs

Changes from v4:
  * Use INTEL_SPI_FIFO_SZ instead of hard coded value of 64 bytes
  * Don't increment i inside call to FDATA() macro
  * Check nor->read_opcode in intel_spi_read() and return
    -EINVAL if not supported. We may add SFDP support later on.

Changes from v3:
  * Added ACKs from Lee Jones.
  * Use bus instead of dev->bus in PCI accesses

Changes from v2:
  * Rebased on top of v4.8-rc2
  * Updated intel_spi_read/write() according spi-nor core changes which
    drops retlen parameter and returns number of bytes read/written.

Changes from v1:
  * Older hardware does not support 64k erase command so added erase_64k
    flag which is set only for Broxton (BXT).
  * Fix protection range offset for Broxton. Now there is ispi->pregs
    pointing to the start of the protection registers.
  * Change naming of constants from BCR_BYT -> BYT_BCR and so on.
  * Drop lpc_ich_finalize_spi_cell() and initialize cell directly in
    lpc_ich_init_spi().
  * Use info->type in switch in lpc_ich_init_spi().
  * Add defines for magic numbers used in lpc_ich_init_spi().
  * Use PLATFORM_DEVID_NONE with mfd_add_devices().

Mika Westerberg (3):
  spi-nor: Add support for Intel SPI serial flash controller
  mfd: lpc_ich: Add support for SPI serial flash host controller
  mfd: lpc_ich: Add support for Intel Apollo Lake SoC

 Documentation/mtd/intel-spi.txt          |  88 ++++
 drivers/mfd/lpc_ich.c                    | 131 ++++++
 drivers/mtd/spi-nor/Kconfig              |  20 +
 drivers/mtd/spi-nor/Makefile             |   2 +
 drivers/mtd/spi-nor/intel-spi-platform.c |  57 +++
 drivers/mtd/spi-nor/intel-spi.c          | 777 +++++++++++++++++++++++++++++++
 drivers/mtd/spi-nor/intel-spi.h          |  24 +
 include/linux/mfd/lpc_ich.h              |   3 +
 include/linux/platform_data/intel-spi.h  |  31 ++
 9 files changed, 1133 insertions(+)
 create mode 100644 Documentation/mtd/intel-spi.txt
 create mode 100644 drivers/mtd/spi-nor/intel-spi-platform.c
 create mode 100644 drivers/mtd/spi-nor/intel-spi.c
 create mode 100644 drivers/mtd/spi-nor/intel-spi.h
 create mode 100644 include/linux/platform_data/intel-spi.h

-- 
2.10.2