1a187559eSBin MengQSPI U-Boot support 22f24223aSPoddar, Sourav------------------ 32f24223aSPoddar, Sourav 42f24223aSPoddar, SouravHost processor is connected to serial flash device via qpsi 52f24223aSPoddar, Souravinterface. QSPI is a kind of spi module that allows single, 62f24223aSPoddar, Souravdual and quad read access to external spi devices. The module 72f24223aSPoddar, Souravhas a memory mapped interface which provide direct interface 82f24223aSPoddar, Souravfor accessing data form external spi devices. 92f24223aSPoddar, Sourav 102f24223aSPoddar, SouravThe one QSPI in the device is primarily intended for fast booting 112f24223aSPoddar, Souravfrom Quad SPI flash devices. 122f24223aSPoddar, Sourav 132f24223aSPoddar, SouravUsecase 142f24223aSPoddar, Sourav------- 152f24223aSPoddar, Sourav 162f24223aSPoddar, SouravMLO/u-boot.img will be flashed from SD/MMC to the flash device 172f24223aSPoddar, Souravusing serial flash erase and write commands. Then, switch settings 182f24223aSPoddar, Souravwill be changed to qspi boot. Then, the ROM code will read MLO 192f24223aSPoddar, Souravfrom the predefined location in the flash, where it was flashed and 202f24223aSPoddar, Souravexecute it after storing it in SDRAM. Then, the MLO will read 212f24223aSPoddar, Souravu-boot.img from flash and execute it from SDRAM. 222f24223aSPoddar, Sourav 232f24223aSPoddar, SouravSPI mode 242f24223aSPoddar, Sourav------- 252f24223aSPoddar, SouravSPI mode uses mtd spi framework for transfer and reception of data. 262f24223aSPoddar, SouravCan be used in: 272f24223aSPoddar, Sourav1. Normal mode: use single pin for transfers 282f24223aSPoddar, Sourav2. Dual Mode: use two pins for transfers. 292f24223aSPoddar, Sourav3. Quad mode: use four pin for transfer 302f24223aSPoddar, Sourav 312f24223aSPoddar, SouravMemory mapped read mode 322f24223aSPoddar, Sourav----------------------- 332f24223aSPoddar, SouravIn this, SPI controller is configured using configuration port and then 34*1cc0a9f4SRobert P. J. Daycontroller is switched to memory mapped port for data read. 352f24223aSPoddar, Sourav 362f24223aSPoddar, SouravDriver 372f24223aSPoddar, Sourav------ 382f24223aSPoddar, Souravdrivers/qspi/ti_qspi.c 392f24223aSPoddar, Sourav - Newly created file which is responsible for configuring the 402f24223aSPoddar, Sourav qspi controller and also for providing the low level api which 412f24223aSPoddar, Sourav is responsible for transferring the datas from host controller 422f24223aSPoddar, Sourav to flash device and vice versa. 432f24223aSPoddar, Sourav 442f24223aSPoddar, SouravTesting 452f24223aSPoddar, Sourav------- 462f24223aSPoddar, SouravA seperated file named README.dra_qspi_test has been created which gives all the 47a187559eSBin Mengdetails about the commands required to test qspi at U-Boot level. 48