[U-Boot] [PATCH 08/11] spi: ti_qspi: Use DMA to read from qspi flash
Tom Rini
trini at konsulko.com
Tue Jul 14 21:02:09 CEST 2015
On Thu, Jul 09, 2015 at 12:10:03PM +0530, Vignesh R wrote:
>
>
> On 07/03/2015 05:12 PM, Tom Rini wrote:
> > On Fri, Jul 03, 2015 at 04:46:10PM +0530, Vignesh R 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>
> >
> > This ignores the feedback from
> > http://lists.denx.de/pipermail/u-boot/2014-July/183715.html where we
> > need to model the DMA changes on how it's done for mxs_spi.c
> >
> Is the following patch an acceptable solution?
>
Jagan, are you OK with the SPI side of this? Thanks!
> 8<-------------------------------------------------------------------
>
> Move DMA related initialization code to helper function in ti-edma3
> driver. Use this function for scheduling DMA transfer from ti_qspi driver.
>
> diff --git a/arch/arm/include/asm/ti-common/ti-edma3.h
> b/arch/arm/include/asm/ti-common/ti-edma3.h
> index 5adc1dac0e65..6a7a321c1bdf 100644
> --- a/arch/arm/include/asm/ti-common/ti-edma3.h
> +++ b/arch/arm/include/asm/ti-common/ti-edma3.h
> @@ -117,5 +117,7 @@ void edma3_set_src_addr(u32 base, int slot, u32 src);
> void edma3_set_transfer_params(u32 base, int slot, int acnt,
> int bcnt, int ccnt, u16 bcnt_rld,
> enum edma3_sync_dimension sync_mode);
> +void edma3_transfer(unsigned long edma3_base_addr, unsigned int
> + edma_slot_num, void *dst, void *src, size_t len);
>
> #endif
> diff --git a/drivers/dma/ti-edma3.c b/drivers/dma/ti-edma3.c
> index 8184ded9fa81..d6a427f2e21d 100644
> --- a/drivers/dma/ti-edma3.c
> +++ b/drivers/dma/ti-edma3.c
> @@ -382,3 +382,81 @@ void qedma3_stop(u32 base, struct
> edma3_channel_config *cfg)
> /* Clear the channel map */
> __raw_writel(0, base + EDMA3_QCHMAP(cfg->chnum));
> }
> +
> +void edma3_transfer(unsigned long edma3_base_addr, unsigned int
> + edma_slot_num, void *dst, void *src, size_t len)
> +{
> + struct edma3_slot_config slot;
> + struct edma3_channel_config edma_channel;
> + int b_cnt_value = 1;
> + int rem_bytes = 0;
> + int a_cnt_value = len;
> + unsigned int addr = (unsigned int) (dst);
> + unsigned int max_acnt = 0x7FFFU;
> +
> + if (len > max_acnt) {
> + b_cnt_value = (len / max_acnt);
> + rem_bytes = (len % max_acnt);
> + a_cnt_value = max_acnt;
> + }
> +
> + slot.opt = 0;
> + slot.src = ((unsigned int) src);
> + slot.acnt = a_cnt_value;
> + slot.bcnt = b_cnt_value;
> + slot.ccnt = 1;
> + slot.src_bidx = a_cnt_value;
> + slot.dst_bidx = a_cnt_value;
> + slot.src_cidx = 0;
> + slot.dst_cidx = 0;
> + slot.link = EDMA3_PARSET_NULL_LINK;
> + slot.bcntrld = 0;
> + slot.opt = EDMA3_SLOPT_TRANS_COMP_INT_ENB |
> + EDMA3_SLOPT_COMP_CODE(0) |
> + EDMA3_SLOPT_STATIC | EDMA3_SLOPT_AB_SYNC;
> +
> + edma3_slot_configure(edma3_base_addr, edma_slot_num, &slot);
> + edma_channel.slot = edma_slot_num;
> + edma_channel.chnum = 0;
> + edma_channel.complete_code = 0;
> + /* set event trigger to dst update */
> + edma_channel.trigger_slot_word = EDMA3_TWORD(dst);
> +
> + qedma3_start(edma3_base_addr, &edma_channel);
> + edma3_set_dest_addr(edma3_base_addr, edma_channel.slot, addr);
> +
> + while (edma3_check_for_transfer(edma3_base_addr, &edma_channel))
> + ;
> + qedma3_stop(edma3_base_addr, &edma_channel);
> +
> + if (rem_bytes != 0) {
> + slot.opt = 0;
> + slot.src =
> + (b_cnt_value * max_acnt) + ((unsigned int) src);
> + slot.acnt = rem_bytes;
> + slot.bcnt = 1;
> + slot.ccnt = 1;
> + slot.src_bidx = rem_bytes;
> + slot.dst_bidx = rem_bytes;
> + slot.src_cidx = 0;
> + slot.dst_cidx = 0;
> + slot.link = EDMA3_PARSET_NULL_LINK;
> + slot.bcntrld = 0;
> + slot.opt = EDMA3_SLOPT_TRANS_COMP_INT_ENB |
> + EDMA3_SLOPT_COMP_CODE(0) |
> + EDMA3_SLOPT_STATIC | EDMA3_SLOPT_AB_SYNC;
> + edma3_slot_configure(edma3_base_addr, edma_slot_num, &slot);
> + edma_channel.slot = edma_slot_num;
> + edma_channel.chnum = 0;
> + edma_channel.complete_code = 0;
> + /* set event trigger to dst update */
> + edma_channel.trigger_slot_word = EDMA3_TWORD(dst);
> +
> + qedma3_start(edma3_base_addr, &edma_channel);
> + edma3_set_dest_addr(edma3_base_addr, edma_channel.slot, addr +
> + (max_acnt * b_cnt_value));
> + while (edma3_check_for_transfer(edma3_base_addr, &edma_channel))
> + ;
> + qedma3_stop(edma3_base_addr, &edma_channel);
> + }
> +}
> 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;
> }
> +#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
>
>
> --
> Regards
> Vignesh
--
Tom
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