Synopsys SSI controllers supporting enhanced SPI mode of operation has SPI Control Register at offset 0xf4 which controls the following: CLK_STRETCH_EN: Enables clock stretching capability in SPI transfers. In case of write, if the FIFO becomes empty DWC_ssi will stretch the clock until FIFO has enough data to continue the transfer. In case of read, if the receive FIFO becomes full DWC_ssi will stop the clock until data has been read from the FIFO. WAIT_CYCLES: Wait cycles in Dual/Quad/Octal mode between control frames transmit and data reception. INST_L: Dual/Quad/Octal mode instruction length in bits. ADDR_L: defines Length of Address to be transmitted. For now, we are only using 32bit Address length and 8 bit Instruction length. Signed-off-by: Sudip Mukherjee <sudip.mukherjee@xxxxxxxxxx> --- drivers/spi/spi-dw.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index b8cc20e0deaa..a7a4637d6d32 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -63,6 +63,17 @@ #define DW_SPI_RX_SAMPLE_DLY 0xf0 #define DW_SPI_CS_OVERRIDE 0xf4 +/* Register offsets (Defined in DWC SSI 1.03a) */ +#define DW_HSSI_SPI_CTRLR0 0xf4 + +/* Bit fields in SPI_CTRLR0 (Defined in DWC SSI 1.03a) */ +#define DW_HSSI_SPI_CTRLR0_CLK_STRETCH_EN BIT(30) +#define DW_HSSI_SPI_CTRLR0_WAIT_CYCLE_MASK GENMASK(15, 11) +#define DW_HSSI_SPI_CTRLR0_INST_L_MASK GENMASK(9, 8) +#define DW_HSSI_SPI_CTRLR0_INST_L8 0x2 +#define DW_HSSI_SPI_CTRLR0_ADDR_L_MASK GENMASK(5, 2) +#define DW_HSSI_SPI_CTRLR0_ADDR_L32 0x8 + /* Bit fields in CTRLR0 (DWC APB SSI) */ #define DW_PSSI_CTRLR0_DFS_MASK GENMASK(3, 0) #define DW_PSSI_CTRLR0_DFS32_MASK GENMASK(20, 16) -- 2.30.2
