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

R, Vignesh vigneshr at ti.com
Mon Aug 17 10:22:14 CEST 2015



On 8/17/2015 1:48 PM, Jagan Teki wrote:
> 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 */

Oops.. Sorry, I overlooked it.. Will add the comment and send it soon.
Thanks!

>> +#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!
> 


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