[U-Boot] [U-Boot RESEND v2 09/10] spi: ti_qspi: Use DMA to read from qspi flash

Jagan Teki jteki at openedev.com
Mon Aug 17 10:18:31 CEST 2015


On 17 August 2015 at 13:29, Vignesh R <vigneshr at ti.com> wrote:
> ti_qspi uses memory map mode for faster read. Enabling DMA will increase
> read speed by 3x @48MHz on DRA74 EVM.
>
> Signed-off-by: Vignesh R <vigneshr at ti.com>
> Reviewed-by: Jagan Teki <jteki at openedev.com>
> ---
>  drivers/spi/ti_qspi.c | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
>
> diff --git a/drivers/spi/ti_qspi.c b/drivers/spi/ti_qspi.c
> index 3356c0f072e5..753d68980bd6 100644
> --- a/drivers/spi/ti_qspi.c
> +++ b/drivers/spi/ti_qspi.c
> @@ -13,6 +13,8 @@
>  #include <spi.h>
>  #include <asm/gpio.h>
>  #include <asm/omap_gpio.h>
> +#include <asm/omap_common.h>
> +#include <asm/ti-common/ti-edma3.h>
>
>  /* ti qpsi register bit masks */
>  #define QSPI_TIMEOUT                    2000000
> @@ -347,3 +349,24 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
>
>         return 0;
>  }
Please add below comment here, I have asked the same on previous version patch
this will track us to the work future.

/* TODO: control from sf layer to here through dm-spi */
> +#ifdef CONFIG_TI_EDMA3
> +void spi_flash_copy_mmap(void *data, void *offset, size_t len)
> +{
> +       unsigned int                    addr = (unsigned int) (data);
> +       unsigned int                    edma_slot_num = 1;
> +
> +       /* Invalidate the area, so no writeback into the RAM races with DMA */
> +       invalidate_dcache_range(addr, addr + roundup(len, ARCH_DMA_MINALIGN));
> +
> +       /* enable edma3 clocks */
> +       enable_edma3_clocks();
> +
> +       /* Call edma3 api to do actual DMA transfer     */
> +       edma3_transfer(EDMA3_BASE, edma_slot_num, data, offset, len);
> +
> +       /* disable edma3 clocks */
> +       disable_edma3_clocks();
> +
> +       *((unsigned int *)offset) += len;
> +}
> +#endif
> --
> 2.5.0

thanks!
-- 
Jagan | openedev.


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