linux/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.yaml
Dmitry Osipenko ce004ae6c5 dt-bindings: memory: tegra20: emc: Document new LPDDR2 sub-node
Some Tegra20 boards don't have RAM code stored in NVMEM, which is used for
the memory chip identification and the identity information should be read
out from LPDDR2 chip in this case. Document new sub-node containing generic
LPDDR2 properties that will be used for the memory chip identification if
RAM code isn't available. The identification is done by reading out memory
configuration values from generic LPDDR2 mode registers of SDRAM chip and
comparing them with the values of device-tree 'lpddr2' sub-node.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211006224659.21434-8-digetx@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
2021-10-15 09:52:47 +02:00

250 lines
6.8 KiB
YAML

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/memory-controllers/nvidia,tegra20-emc.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: NVIDIA Tegra20 SoC External Memory Controller
maintainers:
- Dmitry Osipenko <digetx@gmail.com>
- Jon Hunter <jonathanh@nvidia.com>
- Thierry Reding <thierry.reding@gmail.com>
description: |
The External Memory Controller (EMC) interfaces with the off-chip SDRAM to
service the request stream sent from Memory Controller. The EMC also has
various performance-affecting settings beyond the obvious SDRAM configuration
parameters and initialization settings. Tegra20 EMC supports multiple JEDEC
standard protocols: DDR1, LPDDR2 and DDR2.
properties:
compatible:
const: nvidia,tegra20-emc
reg:
maxItems: 1
clocks:
maxItems: 1
interrupts:
maxItems: 1
"#address-cells":
const: 1
"#size-cells":
const: 0
"#interconnect-cells":
const: 0
nvidia,memory-controller:
$ref: /schemas/types.yaml#/definitions/phandle
description:
Phandle of the Memory Controller node.
power-domains:
maxItems: 1
description:
Phandle of the SoC "core" power domain.
operating-points-v2:
description:
Should contain freqs and voltages and opp-supported-hw property, which
is a bitfield indicating SoC process ID mask.
nvidia,use-ram-code:
type: boolean
description:
If present, the emc-tables@ sub-nodes will be addressed.
$defs:
emc-table:
type: object
properties:
compatible:
const: nvidia,tegra20-emc-table
clock-frequency:
description:
Memory clock rate in kHz.
minimum: 1000
maximum: 900000
reg:
maxItems: 1
description:
Either an opaque enumerator to tell different tables apart, or
the valid frequency for which the table should be used (in kHz).
nvidia,emc-registers:
description:
EMC timing characterization data. These are the registers
(see section "15.4.1 EMC Registers" in the TRM) whose values
need to be specified, according to the board documentation.
$ref: /schemas/types.yaml#/definitions/uint32-array
items:
- description: EMC_RC
- description: EMC_RFC
- description: EMC_RAS
- description: EMC_RP
- description: EMC_R2W
- description: EMC_W2R
- description: EMC_R2P
- description: EMC_W2P
- description: EMC_RD_RCD
- description: EMC_WR_RCD
- description: EMC_RRD
- description: EMC_REXT
- description: EMC_WDV
- description: EMC_QUSE
- description: EMC_QRST
- description: EMC_QSAFE
- description: EMC_RDV
- description: EMC_REFRESH
- description: EMC_BURST_REFRESH_NUM
- description: EMC_PDEX2WR
- description: EMC_PDEX2RD
- description: EMC_PCHG2PDEN
- description: EMC_ACT2PDEN
- description: EMC_AR2PDEN
- description: EMC_RW2PDEN
- description: EMC_TXSR
- description: EMC_TCKE
- description: EMC_TFAW
- description: EMC_TRPAB
- description: EMC_TCLKSTABLE
- description: EMC_TCLKSTOP
- description: EMC_TREFBW
- description: EMC_QUSE_EXTRA
- description: EMC_FBIO_CFG6
- description: EMC_ODT_WRITE
- description: EMC_ODT_READ
- description: EMC_FBIO_CFG5
- description: EMC_CFG_DIG_DLL
- description: EMC_DLL_XFORM_DQS
- description: EMC_DLL_XFORM_QUSE
- description: EMC_ZCAL_REF_CNT
- description: EMC_ZCAL_WAIT_CNT
- description: EMC_AUTO_CAL_INTERVAL
- description: EMC_CFG_CLKTRIM_0
- description: EMC_CFG_CLKTRIM_1
- description: EMC_CFG_CLKTRIM_2
required:
- clock-frequency
- compatible
- reg
- nvidia,emc-registers
additionalProperties: false
patternProperties:
"^emc-table@[0-9]+$":
$ref: "#/$defs/emc-table"
"^emc-tables@[a-z0-9-]+$":
type: object
properties:
reg:
maxItems: 1
description:
An opaque enumerator to tell different tables apart.
nvidia,ram-code:
$ref: /schemas/types.yaml#/definitions/uint32
description:
Value of RAM_CODE this timing set is used for.
"#address-cells":
const: 1
"#size-cells":
const: 0
lpddr2:
$ref: "ddr/jedec,lpddr2.yaml#"
type: object
patternProperties:
"^emc-table@[0-9]+$":
$ref: "#/$defs/emc-table"
oneOf:
- required:
- nvidia,ram-code
- required:
- lpddr2
additionalProperties: false
required:
- compatible
- reg
- interrupts
- clocks
- nvidia,memory-controller
- "#interconnect-cells"
- operating-points-v2
additionalProperties: false
examples:
- |
external-memory-controller@7000f400 {
compatible = "nvidia,tegra20-emc";
reg = <0x7000f400 0x400>;
interrupts = <0 78 4>;
clocks = <&clock_controller 57>;
nvidia,memory-controller = <&mc>;
operating-points-v2 = <&dvfs_opp_table>;
power-domains = <&domain>;
#interconnect-cells = <0>;
#address-cells = <1>;
#size-cells = <0>;
nvidia,use-ram-code;
emc-tables@0 {
nvidia,ram-code = <0>;
reg = <0>;
#address-cells = <1>;
#size-cells = <0>;
emc-table@333000 {
reg = <333000>;
compatible = "nvidia,tegra20-emc-table";
clock-frequency = <333000>;
nvidia,emc-registers = <0x00000018 0x00000033
0x00000012 0x00000004 0x00000004 0x00000005
0x00000003 0x0000000c 0x00000006 0x00000006
0x00000003 0x00000001 0x00000004 0x00000005
0x00000004 0x00000009 0x0000000d 0x00000bff
0x00000000 0x00000003 0x00000003 0x00000006
0x00000006 0x00000001 0x00000011 0x000000c8
0x00000003 0x0000000e 0x00000007 0x00000008
0x00000002 0x00000000 0x00000000 0x00000002
0x00000000 0x00000000 0x00000083 0xf0440303
0x007fe010 0x00001414 0x00000000 0x00000000
0x00000000 0x00000000 0x00000000 0x00000000>;
};
};
emc-tables@1 {
reg = <1>;
lpddr2 {
compatible = "elpida,B8132B2PB-6D-F", "jedec,lpddr2-s4";
revision-id1 = <1>;
density = <2048>;
io-width = <16>;
};
};
};