mtd: spi: renesas: Configure DRDRENR register

Make sure DRDRENR register is configured before performing external
address space read. This register might have been configured by a
prior stage bootloader and leaving it unconfigured would interfere
with U-Boot operation. Since U-Boot RPC SPI driver does not support
DDR data transfer mode yet, set this register unconditionally to 0.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

diff --git a/drivers/spi/renesas_rpc_spi.c b/drivers/spi/renesas_rpc_spi.c
index a2ac5525b90dc3883ea5a51ab61db1d7094f6c76..50890981149b878f34b1fee5820d7b1abce962f8 100644 (file)
--- a/drivers/spi/renesas_rpc_spi.c
+++ b/drivers/spi/renesas_rpc_spi.c
@@ -294,6 +294,7 @@ static int rpc_spi_mem_exec_op(struct spi_slave *spi,
 
                writel(8 * op->dummy.nbytes - 1, priv->regs + RPC_DRDMCR);
                writel(0, priv->regs + RPC_DROPR);
+               writel(0, priv->regs + RPC_DRDRENR);
                writel(smenr, priv->regs + RPC_DRENR);
 
                memcpy_fromio(din, (void *)(priv->extr + offset), op->data.nbytes);