[U-Boot] [PATCH 08/11] spi: ti_qspi: Use DMA to read from qspi flash
R, Vignesh
vigneshr at ti.com
Tue Jul 21 14:41:29 CEST 2015
On 7/15/2015 12:32 AM, Tom Rini wrote:
> 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!
Gentle ping... Any comments? I will send a v2 for this series if the
below patch is acceptable.
>
>> 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
>
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