spi: zynqmp_gqspi: Fix dma alignment issue

DMA is aligned to ARCH_DMA_MINALIGN(64 bytes), but as per spec, alignment
required is 4bytes only. Change DMA alignment from ARCH_DMA_MINALIGN to
GQSPI_DMA_ALIGN. Remove alignment of data length in non-exponential case.

Some minor improvements in the initialization to initialize gen_fifo
threshold and disable qspi controller while setting config register.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/spi/zynqmp_gqspi.c b/drivers/spi/zynqmp_gqspi.c
index 93ba7a0..2db4ae2 100644 (file)
--- a/drivers/spi/zynqmp_gqspi.c
+++ b/drivers/spi/zynqmp_gqspi.c
@@ -77,6 +77,7 @@
 
 #define GQSPI_GFIFO_SELECT             BIT(0)
 #define GQSPI_FIFO_THRESHOLD           1
+#define GQSPI_GENFIFO_THRESHOLD                31
 
 #define SPI_XFER_ON_BOTH               0
 #define SPI_XFER_ON_LOWER              1
@@ -197,7 +198,9 @@ static void zynqmp_qspi_init_hw(struct zynqmp_qspi_priv *priv)
        writel(GQSPI_GFIFO_ALL_INT_MASK, &regs->idisr);
        writel(GQSPI_FIFO_THRESHOLD, &regs->txftr);
        writel(GQSPI_FIFO_THRESHOLD, &regs->rxftr);
+       writel(GQSPI_GENFIFO_THRESHOLD, &regs->gqfthr);
        writel(GQSPI_GFIFO_ALL_INT_MASK, &regs->isr);
+       writel(~GQSPI_ENABLE_ENABLE_MASK, &regs->enbr);
 
        config_reg = readl(&regs->confr);
        config_reg &= ~(GQSPI_GFIFO_STRT_MODE_MASK |
@@ -572,25 +575,20 @@ static int zynqmp_qspi_start_dma(struct zynqmp_qspi_priv *priv,
                                 u32 gen_fifo_cmd, u32 *buf)
 {
        u32 addr;
-       u32 size, len;
+       u32 size;
        u32 actuallen = priv->len;
        int ret = 0;
        struct zynqmp_qspi_dma_regs *dma_regs = priv->dma_regs;
 
        writel((unsigned long)buf, &dma_regs->dmadst);
-       writel(roundup(priv->len, ARCH_DMA_MINALIGN), &dma_regs->dmasize);
+       writel(roundup(priv->len, GQSPI_DMA_ALIGN), &dma_regs->dmasize);
        writel(GQSPI_DMA_DST_I_STS_MASK, &dma_regs->dmaier);
        addr = (unsigned long)buf;
-       size = roundup(priv->len, ARCH_DMA_MINALIGN);
+       size = roundup(priv->len, GQSPI_DMA_ALIGN);
        flush_dcache_range(addr, addr + size);
 
        while (priv->len) {
-               len = zynqmp_qspi_calc_exp(priv, &gen_fifo_cmd);
-               if (!(gen_fifo_cmd & GQSPI_GFIFO_EXP_MASK) &&
-                   (len % ARCH_DMA_MINALIGN)) {
-                       gen_fifo_cmd &= ~GENMASK(7, 0);
-                       gen_fifo_cmd |= roundup(len, ARCH_DMA_MINALIGN);
-               }
+               zynqmp_qspi_calc_exp(priv, &gen_fifo_cmd);
                zynqmp_qspi_fill_gen_fifo(priv, gen_fifo_cmd);
 
                debug("GFIFO_CMD_RX:0x%x\n", gen_fifo_cmd);