Upgrade the SDHCI Cadence controller from SD4HC to SD6HC for Agilex5
platform to support the newer controller version with enhanced features.
Key changes:
- Remove combophy0 node and associated references as SD6HC doesn't require
separate PHY configuration node
- Upgrade MMC controller compatible from "cdns,sd4hc" to "cdns,sd6hc"
- Add Agilex5-specific compatible string "altr,agilex5-sd6hc" for
platform-specific optimizations
Hardware configuration updates:
- Add voltage regulator support:
* sd_emmc_power: Fixed 3.3V regulator for card power supply
* sd_io_1v8_reg: GPIO-controlled regulator for 1.8V/3.3V I/O switching
- Configure proper reset control with named resets including combophy
reset
- Add GPIO control via portb pin 3 for voltage switching
SD card operation:
- Configure for SD card specific operation (no-mmc, cap-sd-highspeed)
- Set maximum frequency to 200MHz
- Configure timing parameters for SD modes:
* Default Speed (DS) and UHS-I SDR12 mode timing:
* High Speed and UHS-I SDR25 mode timing:
- Add PHY timing delays for optimal signal integrity
Signed-off-by: Tanmay Kathpalia <tanmay.kathpalia@altera.com>
Reviewed-by: Tien Fong Chee <tien.fong.chee@altera.com>
eb36736730