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authorAlbert ARIBAUD <albert.u.boot@aribaud.net>2013-06-19 12:53:59 +0200
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>2013-06-19 12:53:59 +0200
commit69f14dc2fd64307f012381dd333a06001dec75dc (patch)
tree1c520dfb9afd8406230a5382ebaf57b0b8cd6c5d /doc
parent847e6693ccb529bf8346db62876f38f0c4e04ade (diff)
parented7bdc03eb516fb698ccc12ec5b4b9f132d05c5f (diff)
Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master'
Conflicts: spl/Makefile
Diffstat (limited to 'doc')
-rw-r--r--doc/device-tree-bindings/exynos/dwmmc.txt54
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+* Exynos 5250 DWC_mobile_storage
+
+The Exynos 5250 provides DWC_mobile_storage interface which supports
+. Embedded Multimedia Cards (EMMC-version 4.5)
+. Secure Digital memory (SD mem-version 2.0)
+. Secure Digital I/O (SDIO-version 3.0)
+. Consumer Electronics Advanced Transport Architecture (CE-ATA-version 1.1)
+
+The Exynos 5250 DWC_mobile_storage provides four channels.
+SOC specific and Board specific properties are channel specific.
+
+Required SoC Specific Properties:
+
+- compatible: should be
+ - samsung,exynos5250-dwmmc: for exynos5250 platforms
+
+- reg: physical base address of the controller and length of memory mapped
+ region.
+
+- interrupts: The interrupt number to the cpu.
+
+Required Board Specific Properties:
+
+- #address-cells: should be 1.
+- #size-cells: should be 0.
+- samsung,bus-width: The width of the bus used to interface the devices
+ supported by DWC_mobile_storage (SD-MMC/EMMC/SDIO).
+ . Typically the bus width is 4 or 8.
+- samsung,timing: The timing values to be written into the
+ Drv/sample clock selection register of corresponding channel.
+ . It is comprised of 3 values corresponding to the 3 fileds
+ 'SelClk_sample', 'SelClk_drv' and 'DIVRATIO' of CLKSEL register.
+ . SelClk_sample: Select sample clock among 8 shifted clocks.
+ . SelClk_drv: Select drv clock among 8 shifted clocks.
+ . DIVRATIO: Clock Divide ratio select.
+ . The above 3 values are used by the clock phase shifter.
+
+Example:
+
+mmc@12200000 {
+ samsung,bus-width = <8>;
+ samsung,timing = <1 3 3>;
+ samsung,removable = <1>;
+}
+In the above example,
+ . The bus width is 8
+ . Timing is comprised of 3 values as explained below
+ 1 - SelClk_sample
+ 3 - SelClk_drv
+ 3 - DIVRATIO
+ . The 'removable' flag indicates whether the the particilar device
+ cannot be removed (always present) or it is a removable device.
+ 1 - Indicates that the device is removable.
+ 0 - Indicates that the device cannot be removed.