diff --git a/arch/risc-v/src/mpfs/mpfs_corespi.c b/arch/risc-v/src/mpfs/mpfs_corespi.c
index 3e23479a5dc64..b6a4d9803c438 100644
--- a/arch/risc-v/src/mpfs/mpfs_corespi.c
+++ b/arch/risc-v/src/mpfs/mpfs_corespi.c
@@ -542,9 +542,9 @@ static uint32_t mpfs_spi_setfrequency(struct spi_dev_s *dev,
 
   priv->frequency = frequency;
 
-  /* Formula is SPICLK = PCLK/(2*(CFG_CLK + 1)) */
+  /* Formula is SPICLK = PCLK/(2*(CFG_CLK + 1)) (result is rounded up) */
 
-  divider = ((MPFS_FPGA_PERIPHERAL_CLK / frequency) >> 1) - 1;
+  divider = (MPFS_FPGA_PERIPHERAL_CLK / frequency) >> 1;
   priv->actual = MPFS_FPGA_PERIPHERAL_CLK / ((divider + 1) << 1);
 
   DEBUGASSERT(divider < 256u);