Re: [PATCH 1/2] media: imx: imx7-media-csi: add support for imx8mq

From: Rui Miguel Silva
Date: Wed Nov 17 2021 - 09:51:56 EST


Hi Martin,
Thanks for the patch.

On Wed Nov 17, 2021 at 9:27 AM WET, Martin Kepplinger wrote:

> Modeled after the NXP driver mx6s_capture.c that this driver is based on,
> imx8mq needs different settings for the baseaddr_switch mechanism. Define
> the needed bits and set that for imx8mq.
>
> Without these settings, the system will "sometimes" hang completely when
> starting to stream (the interrupt will never be called).
>
> Signed-off-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
> ---
> drivers/staging/media/imx/imx7-media-csi.c | 34 ++++++++++++++++++++--
> 1 file changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/media/imx/imx7-media-csi.c b/drivers/staging/media/imx/imx7-media-csi.c
> index 2288dadb2683..8619cf2fc694 100644
> --- a/drivers/staging/media/imx/imx7-media-csi.c
> +++ b/drivers/staging/media/imx/imx7-media-csi.c
> @@ -12,6 +12,7 @@
> #include <linux/interrupt.h>
> #include <linux/mfd/syscon.h>
> #include <linux/module.h>
> +#include <linux/of_device.h>
> #include <linux/of_graph.h>
> #include <linux/pinctrl/consumer.h>
> #include <linux/platform_device.h>
> @@ -122,6 +123,10 @@
> #define BIT_DATA_FROM_MIPI BIT(22)
> #define BIT_MIPI_YU_SWAP BIT(21)
> #define BIT_MIPI_DOUBLE_CMPNT BIT(20)
> +#define BIT_MASK_OPTION_FIRST_FRAME (0 << 18)
> +#define BIT_MASK_OPTION_CSI_EN (1 << 18)
> +#define BIT_MASK_OPTION_SECOND_FRAME (2 << 18)
> +#define BIT_MASK_OPTION_ON_DATA (3 << 18)
> #define BIT_BASEADDR_CHG_ERR_EN BIT(9)
> #define BIT_BASEADDR_SWITCH_SEL BIT(5)
> #define BIT_BASEADDR_SWITCH_EN BIT(4)
> @@ -154,6 +159,12 @@
> #define CSI_CSICR18 0x48
> #define CSI_CSICR19 0x4c
>
> +enum imx_soc {
> + IMX6UL = 0,
> + IMX7,
> + IMX8MQ,

maybe instead of this enum we could use a bool in structure...
>
>+};
> +
> struct imx7_csi {
> struct device *dev;
> struct v4l2_subdev sd;
> @@ -189,6 +200,8 @@ struct imx7_csi {
> bool is_csi2;
>
> struct completion last_eof_completion;
> +
> + enum imx_soc type;

here, bool is_imx8mq?

> };
>
> static struct imx7_csi *
> @@ -537,6 +550,16 @@ static void imx7_csi_deinit(struct imx7_csi *csi,
> clk_disable_unprepare(csi->mclk);
> }
>
> +static void imx8mq_baseaddr_switch(struct imx7_csi *csi)

I think this function needs a better name. First add the imx7_csi
prefix that all functions have, and also you are setting it specific
to second frame and the function should not be specific to imx8.

maybe something:

imx7_csi_write_on_second_frame_enable, maybe?

> +{
> + u32 cr18 = imx7_csi_reg_read(csi, CSI_CSICR18);
> +
> + cr18 |= BIT_BASEADDR_SWITCH_EN | BIT_BASEADDR_SWITCH_SEL |
> + BIT_BASEADDR_CHG_ERR_EN;
> + cr18 |= BIT_MASK_OPTION_SECOND_FRAME;
> + imx7_csi_reg_write(csi, cr18, CSI_CSICR18);
> +}
> +
> static void imx7_csi_enable(struct imx7_csi *csi)
> {
> /* Clear the Rx FIFO and reflash the DMA controller. */
> @@ -551,7 +574,11 @@ static void imx7_csi_enable(struct imx7_csi *csi)
>
> /* Enable the RxFIFO DMA and the CSI. */
> imx7_csi_dmareq_rff_enable(csi);
> +

unrelated new line.

> imx7_csi_hw_enable(csi);
> +
> + if (csi->type == IMX8MQ)
> + imx8mq_baseaddr_switch(csi);

change this to new types and names?

> }
>
> static void imx7_csi_disable(struct imx7_csi *csi)
> @@ -1155,6 +1182,8 @@ static int imx7_csi_probe(struct platform_device *pdev)
> if (IS_ERR(csi->regbase))
> return PTR_ERR(csi->regbase);
>
> + csi->type = (enum imx_soc)of_device_get_match_data(&pdev->dev);

here something:
csi->is_imx8mq = of_device_is_compatible(np, "fsl,imx8mq-csi");
> +
> spin_lock_init(&csi->irqlock);
> mutex_init(&csi->lock);
>
> @@ -1249,8 +1278,9 @@ static int imx7_csi_remove(struct platform_device *pdev)
> }
>
> static const struct of_device_id imx7_csi_of_match[] = {
> - { .compatible = "fsl,imx7-csi" },
> - { .compatible = "fsl,imx6ul-csi" },
> + { .compatible = "fsl,imx8mq-csi", .data = (void *)IMX8MQ },

and with the above you should not need to add the data field here.

------
Cheers,
Rui

> + { .compatible = "fsl,imx7-csi", .data = (void *)IMX7 },
> + { .compatible = "fsl,imx6ul-csi", .data = (void *)IMX6UL },
> { },
> };
> MODULE_DEVICE_TABLE(of, imx7_csi_of_match);
> --
> 2.30.2