diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-15 16:03:25 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-12-15 16:03:25 -0800 |
commit | 991688bfc63550b8c7ab9fb1de2feb44e3071d29 (patch) | |
tree | 1566341d55e1cc56bf9153bc9accc01976b7c87a /Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt | |
parent | 482c3e8835e9e9b325aad295c21bd9e965a11006 (diff) | |
parent | 2ada9593224ccc0f6a9368778dc55a59b92aff10 (diff) |
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Arnd Bergmann:
"Driver updates for ARM SoCs, including a couple of newly added
drivers:
- A new driver for the power management controller on TI Keystone
- Support for the prerelease "SCPI" firmware protocol that ended up
being shipped by Amlogic in their GXBB SoC.
- A soc_device can now be matched using a glob from inside the
kernel, when another driver wants to know the specific chip it is
running on and cannot find out from DT, firmware or hardware.
- Renesas SoCs now support identification through the soc_device
interface, both in user space and kernel.
- Renesas r8a7743 and r8a7745 gain support for their system
controller
- A new checking module for the ARM "PSCI" (not to be confused with
"SCPI" mentioned above) firmware interface.
- A new driver for the Tegra GMI memory interface
- Support for the Tegra firmware interfaces with their power
management controllers
As usual, the updates for the reset controller framework are merged
here, as they tend to touch multiple SoCs as well, including a new
driver for the Oxford (now Broadcom) OX820 chip and the Tegra bpmp
interface.
The existing drivers for Atmel, Qualcomm, NVIDIA, TI Davinci, and
Rockchips SoCs see some further updates"
* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (76 commits)
misc: sram: remove useless #ifdef
drivers: psci: Allow PSCI node to be disabled
drivers: psci: PSCI checker module
soc: renesas: Identify SoC and register with the SoC bus
firmware: qcom: scm: Return PTR_ERR when devm_clk_get fails
firmware: qcom: scm: Remove core, iface and bus clocks dependency
dt-bindings: firmware: scm: Add MSM8996 DT bindings
memory: da8xx-ddrctl: drop the call to of_flat_dt_get_machine_name()
bus: da8xx-mstpri: drop the call to of_flat_dt_get_machine_name()
ARM: shmobile: Document DT bindings for Product Register
soc: renesas: rcar-sysc: add R8A7745 support
reset: Add Tegra BPMP reset driver
dt-bindings: firmware: Allow child nodes inside the Tegra BPMP
dt-bindings: Add power domains to Tegra BPMP firmware
firmware: tegra: Add BPMP support
firmware: tegra: Add IVC library
dt-bindings: firmware: Add bindings for Tegra BPMP
mailbox: tegra-hsp: Use after free in tegra_hsp_remove_doorbells()
mailbox: Add Tegra HSP driver
firmware: arm_scpi: add support for pre-v1.0 SCPI compatible
...
Diffstat (limited to 'Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt')
-rw-r--r-- | Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt b/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt new file mode 100644 index 000000000000..83b0e54f727c --- /dev/null +++ b/Documentation/devicetree/bindings/bus/nvidia,tegra20-gmi.txt @@ -0,0 +1,132 @@ +Device tree bindings for NVIDIA Tegra Generic Memory Interface bus + +The Generic Memory Interface bus enables memory transfers between internal and +external memory. Can be used to attach various high speed devices such as +synchronous/asynchronous NOR, FPGA, UARTS and more. + +The actual devices are instantiated from the child nodes of a GMI node. + +Required properties: + - compatible : Should contain one of the following: + For Tegra20 must contain "nvidia,tegra20-gmi". + For Tegra30 must contain "nvidia,tegra30-gmi". + - reg: Should contain GMI controller registers location and length. + - clocks: Must contain an entry for each entry in clock-names. + - clock-names: Must include the following entries: "gmi" + - resets : Must contain an entry for each entry in reset-names. + - reset-names : Must include the following entries: "gmi" + - #address-cells: The number of cells used to represent physical base + addresses in the GMI address space. Should be 2. + - #size-cells: The number of cells used to represent the size of an address + range in the GMI address space. Should be 1. + - ranges: Must be set up to reflect the memory layout with three integer values + for each chip-select line in use (only one entry is supported, see below + comments): + <cs-number> <offset> <physical address of mapping> <size> + +Note that the GMI controller does not have any internal chip-select address +decoding, because of that chip-selects either need to be managed via software +or by employing external chip-select decoding logic. + +If external chip-select logic is used to support multiple devices it is assumed +that the devices use the same timing and so are probably the same type. It also +assumes that they can fit in the 256MB address range. In this case only one +child device is supported which represents the active chip-select line, see +examples for more insight. + +The chip-select number is decoded from the child nodes second address cell of +'ranges' property, if 'ranges' property is not present or empty chip-select will +then be decoded from the first cell of the 'reg' property. + +Optional child cs node properties: + + - nvidia,snor-data-width-32bit: Use 32bit data-bus, default is 16bit. + - nvidia,snor-mux-mode: Enable address/data MUX mode. + - nvidia,snor-rdy-active-before-data: Assert RDY signal one cycle before data. + If omitted it will be asserted with data. + - nvidia,snor-rdy-active-high: RDY signal is active high + - nvidia,snor-adv-active-high: ADV signal is active high + - nvidia,snor-oe-active-high: WE/OE signal is active high + - nvidia,snor-cs-active-high: CS signal is active high + + Note that there is some special handling for the timing values. + From Tegra TRM: + Programming 0 means 1 clock cycle: actual cycle = programmed cycle + 1 + + - nvidia,snor-muxed-width: Number of cycles MUX address/data asserted on the + bus. Valid values are 0-15, default is 1 + - nvidia,snor-hold-width: Number of cycles CE stays asserted after the + de-assertion of WR_N (in case of SLAVE/MASTER Request) or OE_N + (in case of MASTER Request). Valid values are 0-15, default is 1 + - nvidia,snor-adv-width: Number of cycles during which ADV stays asserted. + Valid values are 0-15, default is 1. + - nvidia,snor-ce-width: Number of cycles before CE is asserted. + Valid values are 0-15, default is 4 + - nvidia,snor-we-width: Number of cycles during which WE stays asserted. + Valid values are 0-15, default is 1 + - nvidia,snor-oe-width: Number of cycles during which OE stays asserted. + Valid values are 0-255, default is 1 + - nvidia,snor-wait-width: Number of cycles before READY is asserted. + Valid values are 0-255, default is 3 + +Example with two SJA1000 CAN controllers connected to the GMI bus. We wrap the +controllers with a simple-bus node since they are all connected to the same +chip-select (CS4), in this example external address decoding is provided: + +gmi@70090000 { + compatible = "nvidia,tegra20-gmi"; + reg = <0x70009000 0x1000>; + #address-cells = <2>; + #size-cells = <1>; + clocks = <&tegra_car TEGRA20_CLK_NOR>; + clock-names = "gmi"; + resets = <&tegra_car 42>; + reset-names = "gmi"; + ranges = <4 0 0xd0000000 0xfffffff>; + + status = "okay"; + + bus@4,0 { + compatible = "simple-bus"; + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 4 0 0x40100>; + + nvidia,snor-mux-mode; + nvidia,snor-adv-active-high; + + can@0 { + reg = <0 0x100>; + ... + }; + + can@40000 { + reg = <0x40000 0x100>; + ... + }; + }; +}; + +Example with one SJA1000 CAN controller connected to the GMI bus +on CS4: + +gmi@70090000 { + compatible = "nvidia,tegra20-gmi"; + reg = <0x70009000 0x1000>; + #address-cells = <2>; + #size-cells = <1>; + clocks = <&tegra_car TEGRA20_CLK_NOR>; + clock-names = "gmi"; + resets = <&tegra_car 42>; + reset-names = "gmi"; + ranges = <4 0 0xd0000000 0xfffffff>; + + status = "okay"; + + can@4,0 { + reg = <4 0 0x100>; + nvidia,snor-mux-mode; + nvidia,snor-adv-active-high; + ... + }; +}; |