dmaengine: ti: k3-udma: Move the TR counter calculation to helper function (a9793407) · Commits · 戴 / test

drivers/dma/ti/k3-udma.c

+51 −23

Original line number	Diff line number	Diff line
		@@ -2029,6 +2029,51 @@ static struct udma_desc udma_alloc_tr_desc(struct udma_chan uc,
		return d;
		}

		/**
		* udma_get_tr_counters - calculate TR counters for a given length
		* @len: Length of the trasnfer
		* @align_to: Preferred alignment
		* @tr0_cnt0: First TR icnt0
		* @tr0_cnt1: First TR icnt1
		* @tr1_cnt0: Second (if used) TR icnt0
		*
		* For len < SZ_64K only one TR is enough, tr1_cnt0 is not updated
		* For len >= SZ_64K two TRs are used in a simple way:
		* First TR: SZ_64K-alignment blocks (tr0_cnt0, tr0_cnt1)
		* Second TR: the remaining length (tr1_cnt0)
		*
		* Returns the number of TRs the length needs (1 or 2)
		* -EINVAL if the length can not be supported
		*/
		static int udma_get_tr_counters(size_t len, unsigned long align_to,
		u16 tr0_cnt0, u16 tr0_cnt1, u16 *tr1_cnt0)
		{
		if (len < SZ_64K) {
		*tr0_cnt0 = len;
		*tr0_cnt1 = 1;

		return 1;
		}

		if (align_to > 3)
		align_to = 3;

		realign:
		*tr0_cnt0 = SZ_64K - BIT(align_to);
		if (len / *tr0_cnt0 >= SZ_64K) {
		if (align_to) {
		align_to--;
		goto realign;
		}
		return -EINVAL;
		}

		tr0_cnt1 = len / tr0_cnt0;
		tr1_cnt0 = len % tr0_cnt0;

		return 2;
		}

		static struct udma_desc *
		udma_prep_slave_sg_tr(struct udma_chan uc, struct scatterlist sgl,
		unsigned int sglen, enum dma_transfer_direction dir,
		@@ -2581,31 +2626,14 @@ udma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
		return NULL;
		}

		if (len < SZ_64K) {
		num_tr = 1;
		tr0_cnt0 = len;
		tr0_cnt1 = 1;
		} else {
		unsigned long align_to = __ffs(src \| dest);

		if (align_to > 3)
		align_to = 3;
		/*
		* Keep simple: tr0: SZ_64K-alignment blocks,
		* tr1: the remaining
		*/
		num_tr = 2;
		tr0_cnt0 = (SZ_64K - BIT(align_to));
		if (len / tr0_cnt0 >= SZ_64K) {
		num_tr = udma_get_tr_counters(len, __ffs(src \| dest), &tr0_cnt0,
		&tr0_cnt1, &tr1_cnt0);
		if (num_tr < 0) {
		dev_err(uc->ud->dev, "size %zu is not supported\n",
		len);
		return NULL;
		}

		tr0_cnt1 = len / tr0_cnt0;
		tr1_cnt0 = len % tr0_cnt0;
		}

		d = udma_alloc_tr_desc(uc, tr_size, num_tr, DMA_MEM_TO_MEM);
		if (!d)
		return NULL;

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