cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i2c-muxes.rst (1719B)

      1.. SPDX-License-Identifier: GPL-2.0
      2
      3==============
      4ACPI I2C Muxes
      5==============
      6
      7Describing an I2C device hierarchy that includes I2C muxes requires an ACPI
      8Device () scope per mux channel.
      9
     10Consider this topology::
     11
     12    +------+   +------+
     13    | SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50)
     14    |      |   | 0x70 |--CH01--> i2c client B (0x50)
     15    +------+   +------+
     16
     17which corresponds to the following ASL::
     18
     19    Device (SMB1)
     20    {
     21        Name (_HID, ...)
     22        Device (MUX0)
     23        {
     24            Name (_HID, ...)
     25            Name (_CRS, ResourceTemplate () {
     26                I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED,
     27                            AddressingMode7Bit, "^SMB1", 0x00,
     28                            ResourceConsumer,,)
     29            }
     30
     31            Device (CH00)
     32            {
     33                Name (_ADR, 0)
     34
     35                Device (CLIA)
     36                {
     37                    Name (_HID, ...)
     38                    Name (_CRS, ResourceTemplate () {
     39                        I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
     40                                    AddressingMode7Bit, "^CH00", 0x00,
     41                                    ResourceConsumer,,)
     42                    }
     43                }
     44            }
     45
     46            Device (CH01)
     47            {
     48                Name (_ADR, 1)
     49
     50                Device (CLIB)
     51                {
     52                    Name (_HID, ...)
     53                    Name (_CRS, ResourceTemplate () {
     54                        I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED,
     55                                    AddressingMode7Bit, "^CH01", 0x00,
     56                                    ResourceConsumer,,)
     57                    }
     58                }
     59            }
     60        }
     61    }