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    Subject[PATCH v2 0/7] Add TI EMIF SDRAM controller driver
    Date
    Add a driver for the EMIF SDRAM controller used in TI SoCs

    EMIF is an SDRAM controller that supports, based on its revision,
    one or more of LPDDR2/DDR2/DDR3 protocols.This driver adds support
    for LPDDR2.

    The driver supports the following features:
    - Calculates the DDR AC timing parameters to be set in EMIF
    registers using data from the device data-sheets and based
    on the DDR frequency. If data from data-sheets is not available
    default timing values from the JEDEC spec are used. These
    will be safe, but not necessarily optimal
    - API for changing timings during DVFS or at boot-up
    - Temperature alert configuration and handling of temperature
    alerts, if any for LPDDR2 devices
    * temperature alert is based on periodic polling of MR4 mode
    register in DDR devices automatically performed by hardware
    * timings are de-rated and brought back to nominal when
    temperature raises and falls respectively
    - Cache of calculated register values to avoid re-calculating
    them

    The driver will need some minor updates when it is eventually
    integrated with Dynamic Voltage and Frequency Scaling (DVFS).
    This can not be done now as DVFS support is not available in
    the mainline yet.

    Discussions with Santosh Shilimkar <santosh.shilimkar@ti.com>
    were immensely helpful in shaping up the interfaces. Vibhore Vardhan
    <vvardhan@gmail.com> did the initial code snippet for thermal
    handling.

    Testing:
    - The driver is tested on OMAP4430 SDP.
    - The driver in a slightly adapted form is also tested on OMAP5.
    - Since mainline kernel doesn't have DVFS support yet,
    testing was done using a test module.
    - Temperature alert handling was tested with simulated interrupts
    and faked temperature values as testing all cases in real-life
    scenarios is difficult.
    - Tested the driver as a module

    Cc: Greg KH <greg@kroah.com>

    v2:
    - Fixed a bug found in the implementation of errata i728
    workaround
    - Fixed the value of frequency printed in debugfs
    - Dropped the hwmod patch as Paul has already posted a
    a hwmod series [1] that adds hwmod for EMIF
    - Converted instances of __init to __init_or_module

    [1] http://thread.gmane.org/gmane.linux.ports.arm.omap/72855

    Aneesh V (7):
    misc: ddr: add LPDDR2 data from JESD209-2
    misc: emif: add register definitions for EMIF
    misc: emif: add basic infrastructure for EMIF driver
    misc: emif: handle frequency and voltage change events
    misc: emif: add interrupt and temperature handling
    misc: emif: add one-time settings
    misc: emif: add debugfs entries for emif

    Documentation/misc-devices/ti-emif.txt | 58 ++
    drivers/misc/Kconfig | 12 +
    drivers/misc/Makefile | 1 +
    drivers/misc/emif.c | 1670 +++++++++++++++++++++++++++++++
    drivers/misc/emif.h | 589 +++++++++++
    include/linux/platform_data/emif_plat.h | 128 +++
    include/misc/jedec_ddr.h | 177 ++++
    lib/Kconfig | 8 +
    lib/Makefile | 3 +
    lib/jedec_ddr_data.c | 135 +++
    10 files changed, 2781 insertions(+), 0 deletions(-)
    create mode 100644 Documentation/misc-devices/ti-emif.txt
    create mode 100644 drivers/misc/emif.c
    create mode 100644 drivers/misc/emif.h
    create mode 100644 include/linux/platform_data/emif_plat.h
    create mode 100644 include/misc/jedec_ddr.h
    create mode 100644 lib/jedec_ddr_data.c



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