The following table lists the flash memory controller clock frequency requirements.
Controller and Mode | Description |
---|---|
Quad-SPI Controller Interface, see the QSPI Clocks section | |
Single, non-manual mode | PMC_IRO_CLK > 3/15 * QSPI_REF_CLK |
Dual stacked, non-manual mode | PMC_IRO_CLK > 3/31 * QSPI_REF_CLK |
Dual parallel, non-manual mode | PMC_IRO_CLK > 3/7 * QSPI_REF_CLK |
Quad-SPI Controller Mode | |
Manual mode, CPOL=1 and CPHA=1 |
QSPI_REF_CLK ≥ PMC_LSBUS_CLK |
All modes with QSPIx_CLK frequency > 37.5 MHz |
QSPI_REF_CLK > 2 * QSPIx_CLK |
Octal-SPI Controller | |
DLL mode |
OSPI_CLK = OSPI_REF_CLK |
Non-DLL mode |
OSPI_CLK ≤ OSPI_REF_CLK / 4 |
SD_eMMC Controller, see the SD Clocks section | |
DLL mode |
SD_DLL_REF_CLK ≥ 6 * SDx_REF_CLK Note: This requires setting the DLL divider to 6
(reset value) or greater.
|
Source these clocks from the same PLL |