Store address width capabilities of DMA controller during init and check
the same per transfer to make sure the bits/word requirement can be met.
Current DW DMA driver requires both tx and rx channel to be configured
and functional hence a subset of both tx and rx channel address width
capability is checked with the width requirement(n_bytes) for a
transfer.
* tested on Baikal-T1 based system with DW SPI-looped back interface
transferring a chunk of data with DFS:8,12,16.
Signed-off-by: Joy Chakraborty <joychakr@google.com
Reviewed-by: Serge Semin <fancer.lancer@gmail.com
Tested-by: Serge Semin <fancer.lancer@gmail.com
Link: https://lore.kernel.org/r/20230512104746.1797865-3-joychakr@google.com
Signed-off-by: Mark Brown <broonie@kernel.org
else
dws->dma_sg_burst = 0;
+ /*
+ * Assuming both channels belong to the same DMA controller hence the
+ * peripheral side address width capabilities most likely would be
+ * the same.
+ */
+ dws->dma_addr_widths = tx.dst_addr_widths & rx.src_addr_widths;
+
return 0;
}
struct spi_device *spi, struct spi_transfer *xfer)
{
struct dw_spi *dws = spi_controller_get_devdata(master);
+ enum dma_slave_buswidth dma_bus_width;
+
+ if (xfer->len <= dws->fifo_len)
+ return false;
+
+ dma_bus_width = dw_spi_dma_convert_width(dws->n_bytes);
- return xfer->len > dws->fifo_len;
+ return dws->dma_addr_widths & BIT(dma_bus_width);
}
static int dw_spi_dma_wait(struct dw_spi *dws, unsigned int len, u32 speed)
struct dma_chan *rxchan;
u32 rxburst;
u32 dma_sg_burst;
+ u32 dma_addr_widths;
unsigned long dma_chan_busy;
dma_addr_t dma_addr; /* phy address of the Data register */
const struct dw_spi_dma_ops *dma_ops;