| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | # SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause |
| 2 | %YAML 1.2 |
| 3 | --- |
| 4 | $id: http://devicetree.org/schemas/iommu/apple,sart.yaml# |
| 5 | $schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | |
| 7 | title: Apple SART DMA address filter |
| 8 | |
| 9 | maintainers: |
| 10 | - Sven Peter <sven@svenpeter.dev> |
| 11 | |
| 12 | description: |
| 13 | Apple SART is a simple address filter for DMA transactions. Regions of |
| 14 | physical memory must be added to the SART's allow list before any |
| 15 | DMA can target these. Unlike a proper IOMMU no remapping can be done and |
| 16 | special support in the consumer driver is required since not all DMA |
| 17 | transactions of a single device are subject to SART filtering. |
| 18 | |
| 19 | SART1 has first been used since at least the A11 (iPhone 8 and iPhone X) |
| 20 | and allows 36 bit of physical address space and filter entries with sizes |
| 21 | up to 24 bit. |
| 22 | |
| 23 | SART2, first seen in A14 and M1, allows 36 bit of physical address space |
| 24 | and filter entry size up to 36 bit. |
| 25 | |
| 26 | SART3, first seen in M1 Pro/Max, extends both the address space and filter |
| 27 | entry size to 42 bit. |
| 28 | |
| 29 | properties: |
| 30 | compatible: |
| 31 | oneOf: |
| 32 | - items: |
| 33 | - const: apple,t8112-sart |
| 34 | - const: apple,t6000-sart |
| 35 | - enum: |
| 36 | - apple,t6000-sart |
| 37 | - apple,t8103-sart |
| 38 | |
| 39 | reg: |
| 40 | maxItems: 1 |
| 41 | |
| 42 | power-domains: |
| 43 | maxItems: 1 |
| 44 | |
| 45 | required: |
| 46 | - compatible |
| 47 | - reg |
| 48 | |
| 49 | additionalProperties: false |
| 50 | |
| 51 | examples: |
| 52 | - | |
| 53 | iommu@7bc50000 { |
| 54 | compatible = "apple,t8103-sart"; |
| 55 | reg = <0x7bc50000 0x4000>; |
| 56 | }; |