Messages in this thread | | | From | Philipp Zabel <> | Subject | [PATCH v2 0/9] Add device tree support for on-chip SRAM | Date | Fri, 31 Aug 2012 11:26:55 +0200 |
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These patches add support to configure on-chip SRAM via device-tree node and to obtain the resulting genalloc pool from a phandle pointing at the node. This allows drivers to allocate SRAM with the genalloc API without hard-coding the genalloc pool address.
The on-chip SRAM on i.MX53 and i.MX6q is registered via device tree and changed to use the simple generic SRAM driver:
ocram: ocram@00900000 { compatible = "fsl,imx-ocram", "sram"; reg = <0x00900000 0x3f000>; };
A driver that needs to allocate SRAM buffers, like the video processing unit on i.MX53, can retrieve the genalloc pool from a phandle in the device tree using of_get_named_gen_pool(node, "iram", 0) from patch 5:
vpu@63ff4000 { /* ... */ iram = <&ocram>; };
Changes since v1: - Added a generic SRAM driver in drivers/misc that does nothing but request/ioremap its given memory region and serve it via the genalloc API. - Renamed the i.MX device tree nodes from "iram" to "ocram".
regards Philipp
--- arch/arm/boot/dts/imx53.dtsi | 5 ++ arch/arm/boot/dts/imx6q.dtsi | 5 ++ arch/arm/plat-mxc/Kconfig | 4 -- arch/arm/plat-mxc/Makefile | 1 - arch/arm/plat-mxc/include/mach/iram.h | 41 ------------- arch/arm/plat-mxc/iram_alloc.c | 73 ----------------------- drivers/misc/Kconfig | 8 +++ drivers/misc/Makefile | 1 + drivers/misc/sram.c | 105 +++++++++++++++++++++++++++++++++ include/linux/genalloc.h | 14 +++++ lib/genalloc.c | 77 ++++++++++++++++++++++++ 11 files changed, 215 insertions(+), 119 deletions(-)
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