diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/cadence_qspi_apb.c | 22 |
1 files changed, 6 insertions, 16 deletions
diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c index 2403e71..b5c664f 100644 --- a/drivers/spi/cadence_qspi_apb.c +++ b/drivers/spi/cadence_qspi_apb.c @@ -273,22 +273,12 @@ void cadence_qspi_apb_config_baudrate_div(void *reg_base, reg = readl(reg_base + CQSPI_REG_CONFIG); reg &= ~(CQSPI_REG_CONFIG_BAUD_MASK << CQSPI_REG_CONFIG_BAUD_LSB); - div = ref_clk_hz / sclk_hz; - - if (div > 32) - div = 32; - - /* Check if even number. */ - if ((div & 1)) { - div = (div / 2); - } else { - if (ref_clk_hz % sclk_hz) - /* ensure generated SCLK doesn't exceed user - specified sclk_hz */ - div = (div / 2); - else - div = (div / 2) - 1; - } + /* + * The baud_div field in the config reg is 4 bits, and the ref clock is + * divided by 2 * (baud_div + 1). Round up the divider to ensure the + * SPI clock rate is less than or equal to the requested clock rate. + */ + div = DIV_ROUND_UP(ref_clk_hz, sclk_hz * 2) - 1; debug("%s: ref_clk %dHz sclk %dHz Div 0x%x\n", __func__, ref_clk_hz, sclk_hz, div); |