[PATCH v2 1/2] spi: pxa2xx: Introduce DMA burst size support

[PATCH v2 1/2] spi: pxa2xx: Introduce DMA burst size support

[Andy Shevchenko]

Some masters may have different DMA burst size than hard coded default.
In such case respect the value given by DMA burst size provided via
platform data.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/spi/spi-pxa2xx-dma.c   | 4 +++-
 drivers/spi/spi-pxa2xx-pci.c   | 5 ++++-
 drivers/spi/spi-pxa2xx.c       | 1 +
 include/linux/spi/pxa2xx_spi.h | 1 +
 4 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
index 2fa7f4b43492..3343fff81c7b 100644
--- a/drivers/spi/spi-pxa2xx-dma.c
+++ b/drivers/spi/spi-pxa2xx-dma.c
@@ -239,13 +239,15 @@ int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
 					   u32 *threshold)
 {
 	struct pxa2xx_spi_chip *chip_info = spi->controller_data;
+	struct driver_data *drv_data = spi_controller_get_devdata(spi->controller);
+	u32 dma_burst_size = drv_data->master_info->dma_burst_size;
 
 	/*
 	 * If the DMA burst size is given in chip_info we use that,
 	 * otherwise we use the default. Also we use the default FIFO
 	 * thresholds for now.
 	 */
-	*burst_code = chip_info ? chip_info->dma_burst_size : 1;
+	*burst_code = chip_info ? chip_info->dma_burst_size : dma_burst_size;
 	*threshold = SSCR1_RxTresh(RX_THRESH_DFLT)
 		   | SSCR1_TxTresh(TX_THRESH_DFLT);
 
diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
index d3de925892cb..3faef7335137 100644
--- a/drivers/spi/spi-pxa2xx-pci.c
+++ b/drivers/spi/spi-pxa2xx-pci.c
@@ -5,7 +5,6 @@
  */
 #include <linux/clk-provider.h>
 #include <linux/module.h>
-#include <linux/of_device.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/spi/pxa2xx_spi.h>
@@ -35,6 +34,8 @@ struct pxa_spi_info {
 	void *tx_param;
 	void *rx_param;
 
+	int dma_burst_size;
+
 	int (*setup)(struct pci_dev *pdev, struct pxa_spi_info *c);
 };
 
@@ -133,6 +134,7 @@ static int mrfld_spi_setup(struct pci_dev *dev, struct pxa_spi_info *c)
 	rx->dma_dev = &dma_dev->dev;
 
 	c->dma_filter = lpss_dma_filter;
+	c->dma_burst_size = 8;
 	return 0;
 }
 
@@ -223,6 +225,7 @@ static int pxa2xx_spi_pci_probe(struct pci_dev *dev,
 	spi_pdata.tx_param = c->tx_param;
 	spi_pdata.rx_param = c->rx_param;
 	spi_pdata.enable_dma = c->rx_param && c->tx_param;
+	spi_pdata.dma_burst_size = c->dma_burst_size ? c->dma_burst_size : 1;
 
 	ssp = &spi_pdata.ssp;
 	ssp->phys_base = pci_resource_start(dev, 0);
diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 8dd67d722aae..7a86654045fc 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1569,6 +1569,7 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev)
 	pdata->is_slave = of_property_read_bool(pdev->dev.of_node, "spi-slave");
 	pdata->num_chipselect = 1;
 	pdata->enable_dma = true;
+	pdata->dma_burst_size = 1;
 
 	return pdata;
 }
diff --git a/include/linux/spi/pxa2xx_spi.h b/include/linux/spi/pxa2xx_spi.h
index b0674e330ef6..154da8cd4781 100644
--- a/include/linux/spi/pxa2xx_spi.h
+++ b/include/linux/spi/pxa2xx_spi.h
@@ -25,6 +25,7 @@ struct dma_chan;
 struct pxa2xx_spi_master {
 	u16 num_chipselect;
 	u8 enable_dma;
+	u8 dma_burst_size;
 	bool is_slave;
 
 	/* DMA engine specific config */
-- 
2.20.1

[PATCH v2 2/2] spi: pxa2xx: Debug print DMA burst and threshold

[Andy Shevchenko]

It's useful during debug to see what DMA burst and threshold sizes are.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/spi/spi-pxa2xx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
index 7a86654045fc..7cc4e85290b0 100644
--- a/drivers/spi/spi-pxa2xx.c
+++ b/drivers/spi/spi-pxa2xx.c
@@ -1338,6 +1338,9 @@ static int setup(struct spi_device *spi)
 			dev_warn(&spi->dev,
 				 "in setup: DMA burst size reduced to match bits_per_word\n");
 		}
+		dev_dbg(&spi->dev,
+			"in setup: DMA burst and threshold set to %u, %u\n",
+			chip->dma_burst_size, chip->dma_threshold);
 	}
 
 	switch (drv_data->ssp_type) {
-- 
2.20.1

Re: [PATCH v2 2/2] spi: pxa2xx: Debug print DMA burst and threshold

[Jarkko Nikula]

On 2/26/19 1:49 PM, Andy Shevchenko wrote:
> It's useful during debug to see what DMA burst and threshold sizes are.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>   drivers/spi/spi-pxa2xx.c | 3 +++
>   1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
> index 7a86654045fc..7cc4e85290b0 100644
> --- a/drivers/spi/spi-pxa2xx.c
> +++ b/drivers/spi/spi-pxa2xx.c
> @@ -1338,6 +1338,9 @@ static int setup(struct spi_device *spi)
>   			dev_warn(&spi->dev,
>   				 "in setup: DMA burst size reduced to match bits_per_word\n");
>   		}
> +		dev_dbg(&spi->dev,
> +			"in setup: DMA burst and threshold set to %u, %u\n",
> +			chip->dma_burst_size, chip->dma_threshold);

Printing chip->dma_threshold is not very informal here just after the 
pxa2xx_spi_set_dma_burst_and_threshold() call which sets it to
(8 - 1 ) << 10 | (8 - 1) << 6 = 7616.

-- 
Jarkko

Re: [PATCH v2 1/2] spi: pxa2xx: Introduce DMA burst size support

[Jarkko Nikula]

On 2/26/19 1:49 PM, Andy Shevchenko wrote:
> Some masters may have different DMA burst size than hard coded default.
> In such case respect the value given by DMA burst size provided via
> platform data.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
>   drivers/spi/spi-pxa2xx-dma.c   | 4 +++-
>   drivers/spi/spi-pxa2xx-pci.c   | 5 ++++-
>   drivers/spi/spi-pxa2xx.c       | 1 +
>   include/linux/spi/pxa2xx_spi.h | 1 +
>   4 files changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c
> index 2fa7f4b43492..3343fff81c7b 100644
> --- a/drivers/spi/spi-pxa2xx-dma.c
> +++ b/drivers/spi/spi-pxa2xx-dma.c
> @@ -239,13 +239,15 @@ int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip,
>   					   u32 *threshold)
>   {
>   	struct pxa2xx_spi_chip *chip_info = spi->controller_data;
> +	struct driver_data *drv_data = spi_controller_get_devdata(spi->controller);
> +	u32 dma_burst_size = drv_data->master_info->dma_burst_size;
>   
>   	/*
>   	 * If the DMA burst size is given in chip_info we use that,
>   	 * otherwise we use the default. Also we use the default FIFO
>   	 * thresholds for now.
>   	 */
> -	*burst_code = chip_info ? chip_info->dma_burst_size : 1;
> +	*burst_code = chip_info ? chip_info->dma_burst_size : dma_burst_size;
>   	*threshold = SSCR1_RxTresh(RX_THRESH_DFLT)
>   		   | SSCR1_TxTresh(TX_THRESH_DFLT);
>   
> diff --git a/drivers/spi/spi-pxa2xx-pci.c b/drivers/spi/spi-pxa2xx-pci.c
> index d3de925892cb..3faef7335137 100644
> --- a/drivers/spi/spi-pxa2xx-pci.c
> +++ b/drivers/spi/spi-pxa2xx-pci.c
> @@ -5,7 +5,6 @@
>    */
>   #include <linux/clk-provider.h>
>   #include <linux/module.h>
> -#include <linux/of_device.h>

Minor note, no need to resend if ok to maintainers:
Unrelated change. Looks like already commit 0202775bc3a2 
("spi/pxa2xx-pci: switch to use pcim_* interfaces") made this needless.

Otherwise looks ok to me.

-- 
Jarkko