Re: [PATCH v5 3/6] irqchip/renesas-rzv2h: Add rzv2h_icu_register_dma_req()

[Lad, Prabhakar]

On Wed, Mar 5, 2025 at 12:22 AM Fabrizio Castro
<fabrizio.castro.jz@xxxxxxxxxxx> wrote:
>
> On the Renesas RZ/V2H(P) family of SoCs, DMAC IPs are connected
> to the Interrupt Control Unit (ICU).
> For DMA transfers, a request number must be registered with the
> ICU, which means that the DMAC driver has to be able to instruct
> the ICU driver with the registration of such id.
>
> Export rzv2h_icu_register_dma_req() so that the DMAC driver can
> register the DMAC request number.
>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
> ---
> v4->v5:
> * Dropped the registration of ACK No.
> * Removed some #define in the driver and in the header file.
> * Renamed the exported function to rzv2h_icu_register_dma_req.
> * Rebased on top of the latest ICU related changes from Biju.
> * Reworked changelog and title.
> * Dropped Thomas' Reviewed-by tag as too much has changed since v4.
> v3->v4:
> * No change.
> v2->v3:
> * Replaced rzv2h_icu_register_dma_req_ack with
>   rzv2h_icu_register_dma_req_ack() in changelog.
> * Added dummy for rzv2h_icu_register_dma_req_ack().
> * Added Rb Thomas.
> v1->v2:
> * Improved macros.
> * Shared new macros for minimum values.
> ---
>  drivers/irqchip/irq-renesas-rzv2h.c       | 35 +++++++++++++++++++++++
>  include/linux/irqchip/irq-renesas-rzv2h.h | 23 +++++++++++++++
>  2 files changed, 58 insertions(+)
>  create mode 100644 include/linux/irqchip/irq-renesas-rzv2h.h
>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

Cheers,
Prabhakar

> diff --git a/drivers/irqchip/irq-renesas-rzv2h.c b/drivers/irqchip/irq-renesas-rzv2h.c
> index 3d5b5fdf9bde..c0322bdfc69f 100644
> --- a/drivers/irqchip/irq-renesas-rzv2h.c
> +++ b/drivers/irqchip/irq-renesas-rzv2h.c
> @@ -15,6 +15,7 @@
>  #include <linux/err.h>
>  #include <linux/io.h>
>  #include <linux/irqchip.h>
> +#include <linux/irqchip/irq-renesas-rzv2h.h>
>  #include <linux/irqdomain.h>
>  #include <linux/of_address.h>
>  #include <linux/of_platform.h>
> @@ -41,6 +42,8 @@
>  #define ICU_TSCLR                              0x24
>  #define ICU_TITSR(k)                           (0x28 + (k) * 4)
>  #define ICU_TSSR(k)                            (0x30 + (k) * 4)
> +#define ICU_DMkSELy(k, y)                      (0x420 + (k) * 0x20 + (y) * 4)
> +#define ICU_DMACKSELk(k)                       (0x500 + (k) * 4)
>
>  /* NMI */
>  #define ICU_NMI_EDGE_FALLING                   0
> @@ -103,6 +106,15 @@ struct rzv2h_hw_info {
>         u8              field_width;
>  };
>
> +/* DMAC */
> +#define ICU_DMAC_DkRQ_SEL_MASK                 GENMASK(9, 0)
> +
> +#define ICU_DMAC_DMAREQ_SHIFT(up)              ((up) * 16)
> +#define ICU_DMAC_DMAREQ_MASK(up)               (ICU_DMAC_DkRQ_SEL_MASK \
> +                                                << ICU_DMAC_DMAREQ_SHIFT(up))
> +#define ICU_DMAC_PREP_DMAREQ(sel, up)          (FIELD_PREP(ICU_DMAC_DkRQ_SEL_MASK, (sel)) \
> +                                                << ICU_DMAC_DMAREQ_SHIFT(up))
> +
>  /**
>   * struct rzv2h_icu_priv - Interrupt Control Unit controller private data structure.
>   * @base:      Controller's base address
> @@ -117,6 +129,27 @@ struct rzv2h_icu_priv {
>         const struct rzv2h_hw_info      *info;
>  };
>
> +void rzv2h_icu_register_dma_req(struct platform_device *icu_dev, u8 dmac_index, u8 dmac_channel,
> +                               u16 req_no)
> +{
> +       struct rzv2h_icu_priv *priv = platform_get_drvdata(icu_dev);
> +       u32 icu_dmksely, dmareq, dmareq_mask;
> +       u8 y, upper;
> +
> +       y = dmac_channel / 2;
> +       upper = dmac_channel % 2;
> +
> +       dmareq = ICU_DMAC_PREP_DMAREQ(req_no, upper);
> +       dmareq_mask = ICU_DMAC_DMAREQ_MASK(upper);
> +
> +       guard(raw_spinlock_irqsave)(&priv->lock);
> +
> +       icu_dmksely = readl(priv->base + ICU_DMkSELy(dmac_index, y));
> +       icu_dmksely = (icu_dmksely & ~dmareq_mask) | dmareq;
> +       writel(icu_dmksely, priv->base + ICU_DMkSELy(dmac_index, y));
> +}
> +EXPORT_SYMBOL_GPL(rzv2h_icu_register_dma_req);
> +
>  static inline struct rzv2h_icu_priv *irq_data_to_priv(struct irq_data *data)
>  {
>         return data->domain->host_data;
> @@ -483,6 +516,8 @@ static int rzv2h_icu_init_common(struct device_node *node, struct device_node *p
>         if (!rzv2h_icu_data)
>                 return -ENOMEM;
>
> +       platform_set_drvdata(pdev, rzv2h_icu_data);
> +
>         rzv2h_icu_data->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
>         if (IS_ERR(rzv2h_icu_data->base))
>                 return PTR_ERR(rzv2h_icu_data->base);
> diff --git a/include/linux/irqchip/irq-renesas-rzv2h.h b/include/linux/irqchip/irq-renesas-rzv2h.h
> new file mode 100644
> index 000000000000..618a60d2eac0
> --- /dev/null
> +++ b/include/linux/irqchip/irq-renesas-rzv2h.h
> @@ -0,0 +1,23 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Renesas RZ/V2H(P) Interrupt Control Unit (ICU)
> + *
> + * Copyright (C) 2025 Renesas Electronics Corporation.
> + */
> +
> +#ifndef __LINUX_IRQ_RENESAS_RZV2H
> +#define __LINUX_IRQ_RENESAS_RZV2H
> +
> +#include <linux/platform_device.h>
> +
> +#define RZV2H_ICU_DMAC_REQ_NO_DEFAULT          0x3ff
> +
> +#ifdef CONFIG_RENESAS_RZV2H_ICU
> +void rzv2h_icu_register_dma_req(struct platform_device *icu_dev, u8 dmac_index, u8 dmac_channel,
> +                               u16 req_no);
> +#else
> +static inline void rzv2h_icu_register_dma_req(struct platform_device *icu_dev, u8 dmac_index,
> +                                             u8 dmac_channel, u16 req_no) { }
> +#endif
> +
> +#endif /* __LINUX_IRQ_RENESAS_RZV2H */
> --
> 2.34.1
>
>