Fix wrong QSPI clock calculation for AM4372

On AM4372 the SPI_GCLK input gets its clock from the PRCM module which
divides the PER_CLKOUTM2 frequency (192MHz) by a fixed factor of 4.
See AM437x Reference Manual in section 27 QSPI >> 27.2 Integration.

The QSPI_FCLK therefore needs to take this factor into account and
becomes (192000000 / 4).

Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>

diff --git a/drivers/spi/ti_qspi.c b/drivers/spi/ti_qspi.c
index c542f40..99acb10 100644 (file)
--- a/drivers/spi/ti_qspi.c
+++ b/drivers/spi/ti_qspi.c
@@ -30,7 +30,8 @@ DECLARE_GLOBAL_DATA_PTR;
 
 /* ti qpsi register bit masks */
 #define QSPI_TIMEOUT                    2000000
-#define QSPI_FCLK                      192000000
+/* AM4372: QSPI gets SPI_GCLK from PRCM unit as PER_CLKOUTM2 divided by 4. */
+#define QSPI_FCLK                       (192000000 / 4)
 #define QSPI_DRA7XX_FCLK                76800000
 #define QSPI_WLEN_MAX_BITS             128
 #define QSPI_WLEN_MAX_BYTES            (QSPI_WLEN_MAX_BITS >> 3)