Re: [PATCH 0/8] Add TI EMIF SDRAM controller driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thursday 08 March 2012 09:24 PM, Aneesh V wrote:
> 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@xxxxxx>
> were immensely helpful in shaping up the interfaces. Vibhore Vardhan
> <vvardhan@xxxxxxxxx> 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@xxxxxxxxx>
> 
> 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
> 
I have scanned all the patches again. Thanks a
lot for taking forward this work. Feel free to
add mine SOB for entire EMIF driver series.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>

Regards
Santosh
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux