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path: root/arch/arm/cpu/armv7/omap4/emif.c
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* omap4: sdram init changes for omap4460Aneesh V2011-08-03-17/+22
| | | | | Signed-off-by: Aneesh V <aneesh@ti.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
* omap4: automatic sdram detectionAneesh V2011-08-03-0/+238
| | | | | | | | | | | | | | | | | | | | | | | | | Identify SDRAM devices connected to EMIF automatically: LPDDR2 devices have some Mode Registers that provide details about the device such as the type, density, bus width etc. EMIF has the capability to read these registers. If there are no devices connected to a given chip-select reading mode registers will return junk values. After reading as many such registers as possible and matching with expected ranges of values the driver can identify if there is a device connected to the respective CS. If we identify that a device is connected the values read give us complete details about the device. This along with the base AC timings specified by JESD209-2 allows us to do a complete automatic initialization of SDRAM that works on all boards. Please note that the default AC timings specified by JESD209-2 will be safe for all devices but not necessarily optimal. However, for the Elpida devices used on Panda and SDP the default timings are both safe and optimal. Signed-off-by: Aneesh V <aneesh@ti.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
* omap4: calculate EMIF register valuesAneesh V2011-08-03-0/+739
| | | | | | | | | | | | | | Calculate EMIF register values based on AC timing parameters from the SDRAM datasheet and the DDR frequency rather than using the hard-coded values. For a new board the user doen't have to go through the tedious process of calculating the register values. Instead, just provide the AC timings from the device data sheet as input and the driver will automatically calculate the register values. Signed-off-by: Aneesh V <aneesh@ti.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>
* omap4: add sdram init supportAneesh V2011-08-03-0/+328
Add support for the SDRAM controller (EMIF). Signed-off-by: Aneesh V <aneesh@ti.com> Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>