On Mon, Jun 16, 2025 at 02:14:24PM +0200, Jacopo Mondi wrote:
> Add a function to perform soft reset of the FCP.
>
> It is intended to support the correct stop procedure of the VSPX-FCPVX
> and VSPD-FCPD pairs according to section "62.3.7.3 Reset Operation" of
> the R-Car Hardware Manual at revision 1.20.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx>
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/platform/renesas/rcar-fcp.c | 41 +++++++++++++++++++++++++++++++
> include/media/rcar-fcp.h | 5 ++++
> 2 files changed, 46 insertions(+)
>
> diff --git a/drivers/media/platform/renesas/rcar-fcp.c b/drivers/media/platform/renesas/rcar-fcp.c
> index cee9bbce4e3affb2467dbc28142e1ab2304bf5b0..584add9f7a803e5ef041589c7c0be7eb8371fe9f 100644
> --- a/drivers/media/platform/renesas/rcar-fcp.c
> +++ b/drivers/media/platform/renesas/rcar-fcp.c
> @@ -9,6 +9,8 @@
>
> #include <linux/device.h>
> #include <linux/dma-mapping.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> #include <linux/list.h>
> #include <linux/module.h>
> #include <linux/mod_devicetable.h>
> @@ -19,14 +21,30 @@
>
> #include <media/rcar-fcp.h>
>
> +#define RCAR_FCP_REG_RST 0x0010
> +#define RCAR_FCP_REG_RST_SOFTRST BIT(0)
> +#define RCAR_FCP_REG_STA 0x0018
> +#define RCAR_FCP_REG_STA_ACT BIT(0)
> +
> struct rcar_fcp_device {
> struct list_head list;
> struct device *dev;
> + void __iomem *base;
> };
>
> static LIST_HEAD(fcp_devices);
> static DEFINE_MUTEX(fcp_lock);
>
> +static inline u32 rcar_fcp_read(struct rcar_fcp_device *fcp, u32 reg)
> +{
> + return ioread32(fcp->base + reg);
> +}
This function isn't used, which generates a compilation warning, see
https://gitlab.freedesktop.org/linux-media/users/pinchartl/-/jobs/78583977.
I will drop it.
> +
> +static inline void rcar_fcp_write(struct rcar_fcp_device *fcp, u32 reg, u32 val)
> +{
> + iowrite32(val, fcp->base + reg);
> +}
> +
> /* -----------------------------------------------------------------------------
> * Public API
> */
> @@ -117,6 +135,25 @@ void rcar_fcp_disable(struct rcar_fcp_device *fcp)
> }
> EXPORT_SYMBOL_GPL(rcar_fcp_disable);
>
> +int rcar_fcp_soft_reset(struct rcar_fcp_device *fcp)
> +{
> + u32 value;
> + int ret;
> +
> + if (!fcp)
> + return 0;
> +
> + rcar_fcp_write(fcp, RCAR_FCP_REG_RST, RCAR_FCP_REG_RST_SOFTRST);
> + ret = readl_poll_timeout(fcp->base + RCAR_FCP_REG_STA,
> + value, !(value & RCAR_FCP_REG_STA_ACT),
> + 1, 100);
> + if (ret)
> + dev_err(fcp->dev, "Failed to soft-reset\n");
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(rcar_fcp_soft_reset);
> +
> /* -----------------------------------------------------------------------------
> * Platform Driver
> */
> @@ -131,6 +168,10 @@ static int rcar_fcp_probe(struct platform_device *pdev)
>
> fcp->dev = &pdev->dev;
>
> + fcp->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(fcp->base))
> + return PTR_ERR(fcp->base);
> +
> dma_set_max_seg_size(fcp->dev, UINT_MAX);
>
> pm_runtime_enable(&pdev->dev);
> diff --git a/include/media/rcar-fcp.h b/include/media/rcar-fcp.h
> index 179240fb163bd2e7cc347e559f99bae943bf0e34..6ac9be9f675e667d6482a5a2483963fa52a0c622 100644
> --- a/include/media/rcar-fcp.h
> +++ b/include/media/rcar-fcp.h
> @@ -18,6 +18,7 @@ void rcar_fcp_put(struct rcar_fcp_device *fcp);
> struct device *rcar_fcp_get_device(struct rcar_fcp_device *fcp);
> int rcar_fcp_enable(struct rcar_fcp_device *fcp);
> void rcar_fcp_disable(struct rcar_fcp_device *fcp);
> +int rcar_fcp_soft_reset(struct rcar_fcp_device *fcp);
> #else
> static inline struct rcar_fcp_device *rcar_fcp_get(const struct device_node *np)
> {
> @@ -33,6 +34,10 @@ static inline int rcar_fcp_enable(struct rcar_fcp_device *fcp)
> return 0;
> }
> static inline void rcar_fcp_disable(struct rcar_fcp_device *fcp) { }
> +static inline int rcar_fcp_soft_reset(struct rcar_fcp_device *fcp)
> +{
> + return 0;
> +}
> #endif
>
> #endif /* __MEDIA_RCAR_FCP_H__ */
>
--
Regards,
Laurent Pinchart
