1. remove redundant SPI clock settings, use rom functions to set clock.
2. remove redundant SPI cs setup and hold settings.
3. for old 32Mbit psram, cs hold time must only be 0.5T due to the special driving mode.(cs_setup = 0; cs_hold = 0)
4. for new 64Mbit psram, cs hold time is recommended to be 2.5T. (cs_setup = 1, cs_setup_time = 0;cs_hold = 1, cs_hold_time = 1)
1. esp32-pico use standard spi driver to access psram
2. for esp32-pico, flash and psram share the clock
3. for esp32-pico, psram cs io can be overwrite via menuconfig
1. Use BIT[7:5] of EID to determine psram size
2. Add ID support for 16Mbit psram
3. Remove module reset on SPI1
4. Confirmed with the vendor that only the old 32Mbit psram need special clock timing. For other psram chips, we should use standard QPI mode.
1. remove use EID to distinguish psram voltage
2. 1V8 64Mbit psram and 3V3 64Mbit psram use the same psram driver(standard spi interface)
3. set cs hold time register as 1
1. Add reading psram EID.
2. Configure different clock mode for different EID.
3. add API to get psram size and voltage.
4. Remove unnecessary VSPI claim.
For 32MBit@1.8V and 64MBit@3.3V psram, there should be 2 extra clock cycles after CS get high level.
For 64MBit@1.8 psram, we can just use standard SPI protocol to drive the psram. We also need to increase the HOLD time for CS in this case.
EID for psram:
32MBit 1.8v: 0x20
64MBit 1.8v: 0x26
64MBit 3.3v: 0x46
1. Bootloader reads SPI configuration from bin header, so that the burning configuration can be different with compiling configuration.
2. Psram mode init will overwrite original flash speed mode, so that users can change psram and flash speed after OTA. 3. Flash read mode(QIO/DIO…) will not be changed in app bin. It is decided by bootloader, OTA can not change this mode.
4. Add read flash ID function, and save flash ID in g_rom_flashchip
5. Set drive ability for all related GPIOs
6. Check raise VDDSDIO voltage in 80Mhz mode
7. Add check flash ID and update settings in bootloader
8. Read flash ID once and keep in global variable
9. Read flash image header once and reuse the result
Tested cases:
1. Test new and old version of bootloader
boot Flash 20M —> app Flash 80M + Psram 80M
boot Flash 40M —> app Flash 80M + Psram 80M
boot Flash 80M —> app Flash 80M + Psram 80M
boot Flash 20M —> app Flash 80M + Psram 40M
boot Flash 40M —> app Flash 80M + Psram 40M
boot Flash 80M —> app Flash 80M + Psram 40M
boot Flash 20M —> app Flash 40M + Psram 40M
boot Flash 40M —> app Flash 40M + Psram 40M
boot Flash 80M —> app Flash 40M + Psram 40M 2. Working after esp_restart reboot.
