From c4ec7430c30a4012a04aa5535919845f543f075d Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Tue, 22 Apr 2014 23:26:12 +0200 Subject: memory: mvebu-devbus: add Orion5x support This commit adds support for the Orion5x family of Marvell processors into the mvebu-devbus driver. It differs from the already supported Armada 370/XP by: * Having a single register (instead of two) for doing all the timing configuration. * Having a few less timing configuration parameters. For this reason, a separate compatible string "marvell,orion-devbus" is introduced. Signed-off-by: Thomas Petazzoni Acked-by: Sebastian Hesselbarth Tested-by: Ezequiel Garcia Link: https://lkml.kernel.org/r/1398202002-28530-9-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper --- .../bindings/memory-controllers/mvebu-devbus.txt | 25 +++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) (limited to 'Documentation/devicetree/bindings/memory-controllers') diff --git a/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt b/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt index 653c90c34a71..55adde214627 100644 --- a/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt +++ b/Documentation/devicetree/bindings/memory-controllers/mvebu-devbus.txt @@ -6,10 +6,11 @@ The actual devices are instantiated from the child nodes of a Device Bus node. Required properties: - - compatible: Currently only Armada 370/XP SoC are supported, - with this compatible string: + - compatible: Armada 370/XP SoC are supported using the + "marvell,mvebu-devbus" compatible string. - marvell,mvebu-devbus + Orion5x SoC are supported using the + "marvell,orion-devbus" compatible string. - reg: A resource specifier for the register space. This is the base address of a chip select within @@ -22,7 +23,7 @@ Required properties: integer values for each chip-select line in use: 0 -Mandatory timing properties for child nodes: +Timing properties for child nodes: Read parameters: @@ -30,21 +31,26 @@ Read parameters: drive the AD bus after the completion of a device read. This prevents contentions on the Device Bus after a read cycle from a slow device. + Mandatory. - - devbus,bus-width: Defines the bus width (e.g. <16>) + - devbus,bus-width: Defines the bus width, in bits (e.g. <16>). + Mandatory. - devbus,badr-skew-ps: Defines the time delay from from A[2:0] toggle, to read data sample. This parameter is useful for synchronous pipelined devices, where the address precedes the read data by one or two cycles. + Mandatory. - devbus,acc-first-ps: Defines the time delay from the negation of ALE[0] to the cycle that the first read data is sampled by the controller. + Mandatory. - devbus,acc-next-ps: Defines the time delay between the cycle that samples data N and the cycle that samples data N+1 (in burst accesses). + Mandatory. - devbus,rd-setup-ps: Defines the time delay between DEV_CSn assertion to DEV_OEn assertion. If set to 0 (default), @@ -52,6 +58,8 @@ Read parameters: This parameter has no affect on parameter (no affect on first data sample). Set to a value smaller than . + Mandatory for "marvell,mvebu-devbus" + compatible string, ignored otherwise. - devbus,rd-hold-ps: Defines the time between the last data sample to the de-assertion of DEV_CSn. If set to 0 (default), @@ -62,16 +70,20 @@ Read parameters: last data sampled. Also this parameter has no affect on parameter. Set to a value smaller than . + Mandatory for "marvell,mvebu-devbus" + compatible string, ignored otherwise. Write parameters: - devbus,ale-wr-ps: Defines the time delay from the ALE[0] negation cycle to the DEV_WEn assertion. + Mandatory. - devbus,wr-low-ps: Defines the time during which DEV_WEn is active. A[2:0] and Data are kept valid as long as DEV_WEn is active. This parameter defines the setup time of address and data to DEV_WEn rise. + Mandatory. - devbus,wr-high-ps: Defines the time during which DEV_WEn is kept inactive (high) between data beats of a burst write. @@ -79,10 +91,13 @@ Write parameters: - ps. This parameter defines the hold time of address and data after DEV_WEn rise. + Mandatory. - devbus,sync-enable: Synchronous device enable. 1: True 0: False + Mandatory for "marvell,mvebu-devbus" compatible + string, ignored otherwise. An example for an Armada XP GP board, with a 16 MiB NOR device as child is showed below. Note that the Device Bus driver is in charge of allocating -- cgit v1.2.3-55-g7522