vasilito/RedBear-OS
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

intel: add DP protocol comments to dp_aux.rs constants

Browse Source 
Document DisplayPort 1.4 specification constants:
  AUX channel register layout (0x64010 base, 0x100 stride)
  AUX transaction timeout rationale (300us spec + PM margin)
  DPCD capability register addresses (revision, link rate, lane count)
  I2C-over-AUX EDID addressing (0x50 EEPROM, segment pointers)
  AUX transaction types (native READ/WRITE, I2C READ/WRITE, MOT flag)
This commit is contained in:
Admin Pupkin
2026-06-02 10:45:35 +03:00
parent 18017316ac
commit a9f44c331c
1 changed files with 7 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files
local/recipes/gpu/redox-drm/source/src/drivers/intel/dp_aux.rs
+7 -1
View File
@@ -17,27 +17,33 @@ const DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT: u32 = 20;
const DP_AUX_CH_CTL_MESSAGE_SIZE_MASK: u32 = 0x1F;
const DP_AUX_CH_CTL_SEND: u32 = 1 << 0;
// DP AUX channel register base. Each port has its own set at AUX_STRIDE intervals.
const DP_AUX_CTL_BASE: usize = 0x64010;
const DP_AUX_DATA_BASE: usize = 0x64014;
const AUX_STRIDE: usize = 0x100;
// AUX transaction timeout in milliseconds. The DP spec allows up to 300us for
// AUX native transactions, but sink devices may take longer under power management.
const AUX_TIMEOUT_MS: u64 = 10;
const AUX_DEFER_MAX_RETRIES: u32 = 7;
// DPCD register addresses for capability discovery and sink communication.
const DPCD_REV: u32 = 0x0000;
const DPCD_MAX_LINK_RATE: u16 = 0x0001;
const DPCD_MAX_LANE_COUNT: u16 = 0x0002;
// I2C-over-AUX addresses for EDID. The EDID EEPROM is always at I2C address 0x50.
const EDID_I2C_ADDRESS: u8 = 0x50;
const EDID_SEGMENT_ADDR: u8 = 0x30;
const EDID_DDC_SEGMENT_ADDR: u8 = 0x60;
const EDID_LENGTH: usize = 128;
// AUX transaction types as defined by the DP 1.4 specification.
const AUX_NATIVE_WRITE: u8 = 0x00;
const AUX_NATIVE_READ: u8 = 0x01;
const AUX_I2C_WRITE: u8 = 0x04;
const AUX_I2C_READ: u8 = 0x05;
const AUX_I2C_MOT: u8 = 0x02;
const AUX_I2C_MOT: u8 = 0x02; // Middle-of-Transaction flag for multi-byte I2C
pub struct DpAux {
mmio: Arc<MmioRegion>,