Re: [RESEND PATCH v7 1/1] firmware: mediatek: add adsp ipc protocol interface

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, May 05, 2022 at 01:30:48PM +0800, Tinghan Shen wrote:
> From: TingHan Shen <tinghan.shen@mediatek.com>
> 
> Some of mediatek processors contain
> the Tensilica HiFix DSP for audio processing.
> 
> The communication between Host CPU and DSP firmware is
> taking place using a shared memory area for message passing.
> 
> ADSP IPC protocol offers (send/recv) interfaces using
> mediatek-mailbox APIs.
> 
> We use two mbox channels to implement a request-reply protocol.
> 
> Signed-off-by: Allen-KH Cheng <allen-kh.cheng@mediatek.com>
> Signed-off-by: TingHan Shen <tinghan.shen@mediatek.com>
> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> Reviewed-by: Curtis Malainey <cujomalainey@chromium.org>
> Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
> Reviewed-by: YC Hung <yc.hung@mediatek.com>
> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> ---
>  drivers/firmware/Kconfig                      |   1 +
>  drivers/firmware/Makefile                     |   1 +
>  drivers/firmware/mediatek/Kconfig             |   9 +
>  drivers/firmware/mediatek/Makefile            |   2 +
>  drivers/firmware/mediatek/mtk-adsp-ipc.c      | 161 ++++++++++++++++++
>  .../linux/firmware/mediatek/mtk-adsp-ipc.h    |  65 +++++++
>  6 files changed, 239 insertions(+)
>  create mode 100644 drivers/firmware/mediatek/Kconfig
>  create mode 100644 drivers/firmware/mediatek/Makefile
>  create mode 100644 drivers/firmware/mediatek/mtk-adsp-ipc.c
>  create mode 100644 include/linux/firmware/mediatek/mtk-adsp-ipc.h
> 
> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> index d65964996e8d..c4d149b28944 100644
> --- a/drivers/firmware/Kconfig
> +++ b/drivers/firmware/Kconfig
> @@ -300,6 +300,7 @@ source "drivers/firmware/cirrus/Kconfig"
>  source "drivers/firmware/google/Kconfig"
>  source "drivers/firmware/efi/Kconfig"
>  source "drivers/firmware/imx/Kconfig"
> +source "drivers/firmware/mediatek/Kconfig"
>  source "drivers/firmware/meson/Kconfig"
>  source "drivers/firmware/psci/Kconfig"
>  source "drivers/firmware/smccc/Kconfig"
> diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
> index 4e58cb474a68..88fbdc110100 100644
> --- a/drivers/firmware/Makefile
> +++ b/drivers/firmware/Makefile
> @@ -34,6 +34,7 @@ obj-$(CONFIG_GOOGLE_FIRMWARE)	+= google/
>  obj-$(CONFIG_EFI)		+= efi/
>  obj-$(CONFIG_UEFI_CPER)		+= efi/
>  obj-y				+= imx/
> +obj-y				+= mediatek/
>  obj-y				+= psci/
>  obj-y				+= smccc/
>  obj-y				+= tegra/
> diff --git a/drivers/firmware/mediatek/Kconfig b/drivers/firmware/mediatek/Kconfig
> new file mode 100644
> index 000000000000..6d1e580b967b
> --- /dev/null
> +++ b/drivers/firmware/mediatek/Kconfig
> @@ -0,0 +1,9 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +config MTK_ADSP_IPC
> +	tristate "MTK ADSP IPC Protocol driver"
> +	depends on MTK_ADSP_MBOX
> +	help
> +	  Say yes here to add support for the MediaTek ADSP IPC
> +	  between host AP (Linux) and the firmware running on ADSP.
> +	  ADSP exists on some mtk processors.
> +	  Client might use shared memory to exchange information with ADSP side.
> diff --git a/drivers/firmware/mediatek/Makefile b/drivers/firmware/mediatek/Makefile
> new file mode 100644
> index 000000000000..4e840b65650d
> --- /dev/null
> +++ b/drivers/firmware/mediatek/Makefile
> @@ -0,0 +1,2 @@
> +# SPDX-License-Identifier: GPL-2.0
> +obj-$(CONFIG_MTK_ADSP_IPC)		+= mtk-adsp-ipc.o
> diff --git a/drivers/firmware/mediatek/mtk-adsp-ipc.c b/drivers/firmware/mediatek/mtk-adsp-ipc.c
> new file mode 100644
> index 000000000000..87cee61dbf32
> --- /dev/null
> +++ b/drivers/firmware/mediatek/mtk-adsp-ipc.c
> @@ -0,0 +1,161 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (c) 2022 MediaTek Corporation. All rights reserved.
> + * Author: Allen-KH Cheng <allen-kh.cheng@mediatek.com>
> + */
> +
> +#include <linux/firmware/mediatek/mtk-adsp-ipc.h>
> +#include <linux/kernel.h>
> +#include <linux/mailbox_client.h>
> +#include <linux/module.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +
> +/*
> + * mtk_adsp_ipc_send - send ipc cmd to MTK ADSP
> + *
> + * @ipc: ADSP IPC handle
> + * @idx: index of the mailbox channel
> + * @msg: IPC cmd (reply or request)
> + *
> + * Returns zero for success from mbox_send_message
> + * negative value for error
> + */
> +int mtk_adsp_ipc_send(struct mtk_adsp_ipc *ipc, unsigned int idx, uint32_t msg)
> +{
> +	struct mtk_adsp_chan *adsp_chan;
> +	int ret;
> +
> +	if (idx >= MTK_ADSP_MBOX_NUM)
> +		return -EINVAL;
> +
> +	adsp_chan = &ipc->chans[idx];
> +	ret = mbox_send_message(adsp_chan->ch, &msg);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * mbox_send_message returns non-negative value on success,
> +	 * return zero for success
> +	 */
> +	return 0;

You already said this up in the function comments, no need to duplicate
it again.

> +}
> +EXPORT_SYMBOL(mtk_adsp_ipc_send);

EXPORT_SYMBOL_GPL()?  I have to ask, sorry.

thanks,

greg k-h