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[1/2] soc: qcom: geni-se: Add interfaces geni_se_tx_init_dma() and geni_se_rx_init_dma()

Message ID 1683911265-3395-2-git-send-email-quic_vnivarth@quicinc.com (mailing list archive)
State New, archived
Headers show
Series spi: spi-geni-qcom: Add new interfaces and utilise them to do map/unmap in framework for SE DMA | expand

Commit Message

Vijaya Krishna Nivarthi May 12, 2023, 5:07 p.m. UTC 
The geni_se_xx_dma_prep() interfaces necessarily do DMA mapping before
initiating DMA transfers. This is not suitable for spi where framework
is expected to handle map/unmap.

Expose new interfaces geni_se_xx_init_dma() which do only DMA transfer.

Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
---
 drivers/soc/qcom/qcom-geni-se.c  | 67 +++++++++++++++++++++++++++++-----------
 include/linux/soc/qcom/geni-se.h |  4 +++
 2 files changed, 53 insertions(+), 18 deletions(-)

Comments

Doug Anderson May 15, 2023, 4:10 p.m. UTC | #1 
Hi,

On Fri, May 12, 2023 at 10:07 AM Vijaya Krishna Nivarthi
<quic_vnivarth@quicinc.com> wrote:
>
> The geni_se_xx_dma_prep() interfaces necessarily do DMA mapping before
> initiating DMA transfers. This is not suitable for spi where framework
> is expected to handle map/unmap.
>
> Expose new interfaces geni_se_xx_init_dma() which do only DMA transfer.
>
> Signed-off-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
> ---
>  drivers/soc/qcom/qcom-geni-se.c  | 67 +++++++++++++++++++++++++++++-----------
>  include/linux/soc/qcom/geni-se.h |  4 +++
>  2 files changed, 53 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
> index 795a2e1..adfcd6e 100644
> --- a/drivers/soc/qcom/qcom-geni-se.c
> +++ b/drivers/soc/qcom/qcom-geni-se.c
> @@ -682,6 +682,30 @@ EXPORT_SYMBOL(geni_se_clk_freq_match);
>  #define GENI_SE_DMA_EOT_EN BIT(1)
>  #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
>  #define GENI_SE_DMA_EOT_BUF BIT(0)
> +
> +/**
> + * geni_se_tx_init_dma() - Initiate TX DMA transfer on the serial engine
> + * @se:                        Pointer to the concerned serial engine.
> + * @iova:              Pointer to store the mapped DMA address.

We're not returning the "iova" from this function, so it shouldn't say
"Pointer to store".


> + * @len:               Length of the TX buffer.
> + *
> + * This function is used to initiate DMA TX transfer.
> + */
> +void geni_se_tx_init_dma(struct geni_se *se, dma_addr_t *iova, size_t len)

There is no reason to pass iova as a pointer, right? Change it to just
"dma_addr_t"


Same comments on the RX side of things.


-Doug
diff mbox series

Patch

diff --git a/drivers/soc/qcom/qcom-geni-se.c b/drivers/soc/qcom/qcom-geni-se.c
index 795a2e1..adfcd6e 100644
--- a/drivers/soc/qcom/qcom-geni-se.c
+++ b/drivers/soc/qcom/qcom-geni-se.c
@@ -682,6 +682,30 @@  EXPORT_SYMBOL(geni_se_clk_freq_match);
 #define GENI_SE_DMA_EOT_EN BIT(1)
 #define GENI_SE_DMA_AHB_ERR_EN BIT(2)
 #define GENI_SE_DMA_EOT_BUF BIT(0)
+
+/**
+ * geni_se_tx_init_dma() - Initiate TX DMA transfer on the serial engine
+ * @se:			Pointer to the concerned serial engine.
+ * @iova:		Pointer to store the mapped DMA address.
+ * @len:		Length of the TX buffer.
+ *
+ * This function is used to initiate DMA TX transfer.
+ */
+void geni_se_tx_init_dma(struct geni_se *se, dma_addr_t *iova, size_t len)
+{
+	u32 val;
+
+	val = GENI_SE_DMA_DONE_EN;
+	val |= GENI_SE_DMA_EOT_EN;
+	val |= GENI_SE_DMA_AHB_ERR_EN;
+	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
+	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
+	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
+	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
+	writel(len, se->base + SE_DMA_TX_LEN);
+}
+EXPORT_SYMBOL(geni_se_tx_init_dma);
+
 /**
  * geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
  * @se:			Pointer to the concerned serial engine.
@@ -697,7 +721,6 @@  int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
 			dma_addr_t *iova)
 {
 	struct geni_wrapper *wrapper = se->wrapper;
-	u32 val;
 
 	if (!wrapper)
 		return -EINVAL;
@@ -706,17 +729,34 @@  int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
 	if (dma_mapping_error(wrapper->dev, *iova))
 		return -EIO;
 
+	geni_se_tx_init_dma(se, iova, len);
+	return 0;
+}
+EXPORT_SYMBOL(geni_se_tx_dma_prep);
+
+/**
+ * geni_se_rx_init_dma() - Initiate RX DMA transfer on the serial engine
+ * @se:			Pointer to the concerned serial engine.
+ * @iova:		Pointer to store the mapped DMA address.
+ * @len:		Length of the RX buffer.
+ *
+ * This function is used to initiate DMA RX transfer.
+ */
+void geni_se_rx_init_dma(struct geni_se *se, dma_addr_t *iova, size_t len)
+{
+	u32 val;
+
 	val = GENI_SE_DMA_DONE_EN;
 	val |= GENI_SE_DMA_EOT_EN;
 	val |= GENI_SE_DMA_AHB_ERR_EN;
-	writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
-	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
-	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
-	writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
-	writel(len, se->base + SE_DMA_TX_LEN);
-	return 0;
+	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
+	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
+	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
+	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
+	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
+	writel(len, se->base + SE_DMA_RX_LEN);
 }
-EXPORT_SYMBOL(geni_se_tx_dma_prep);
+EXPORT_SYMBOL(geni_se_rx_init_dma);
 
 /**
  * geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
@@ -733,7 +773,6 @@  int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
 			dma_addr_t *iova)
 {
 	struct geni_wrapper *wrapper = se->wrapper;
-	u32 val;
 
 	if (!wrapper)
 		return -EINVAL;
@@ -742,15 +781,7 @@  int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
 	if (dma_mapping_error(wrapper->dev, *iova))
 		return -EIO;
 
-	val = GENI_SE_DMA_DONE_EN;
-	val |= GENI_SE_DMA_EOT_EN;
-	val |= GENI_SE_DMA_AHB_ERR_EN;
-	writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
-	writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
-	writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
-	/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
-	writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
-	writel(len, se->base + SE_DMA_RX_LEN);
+	geni_se_rx_init_dma(se, iova, len);
 	return 0;
 }
 EXPORT_SYMBOL(geni_se_rx_dma_prep);
diff --git a/include/linux/soc/qcom/geni-se.h b/include/linux/soc/qcom/geni-se.h
index c55a0bc..7a2a546 100644
--- a/include/linux/soc/qcom/geni-se.h
+++ b/include/linux/soc/qcom/geni-se.h
@@ -490,9 +490,13 @@  int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
 			   unsigned int *index, unsigned long *res_freq,
 			   bool exact);
 
+void geni_se_tx_init_dma(struct geni_se *se, dma_addr_t *iova, size_t len);
+
 int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
 			dma_addr_t *iova);
 
+void geni_se_rx_init_dma(struct geni_se *se, dma_addr_t *iova, size_t len);
+
 int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
 			dma_addr_t *iova);