Date:   Wed, 22 Feb 2023 10:34:48 -0700
From:   Mathieu Poirier <mathieu.poirier@linaro.org>
To:     Tanmay Shah <tanmay.shah@amd.com>
Cc:     michal.simek@amd.com, andersson@kernel.org,
        jaswinder.singh@linaro.org, ben.levinsky@amd.com,
        shubhrajyoti.datta@amd.com, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-remoteproc@vger.kernel.org
Subject: Re: [PATCH v3 1/3] drivers: mailbox: zynqmp: handle multiple child
 nodes
Message-ID: <20230222173448.GA909075@p14s>
References: <20230213211825.3507034-1-tanmay.shah@amd.com>
 <20230213211825.3507034-2-tanmay.shah@amd.com>
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On Mon, Feb 13, 2023 at 01:18:24PM -0800, Tanmay Shah wrote:
> As of now only one child node is handled by zynqmp-ipi
> mailbox driver. Upon introducing remoteproc r5 core mailbox
> nodes, found few enhancements in Xilinx zynqmp mailbox driver
> as following:
> 
> - fix mailbox child node counts
>   If child mailbox node status is disabled it causes
>   crash in interrupt handler. Fix this by assigning
>   only available child node during driver probe.
> 
> - fix typo in IPI documentation %s/12/32/
>   Xilinx IPI message buffers allows 32-byte data transfer.
>   Fix documentation that says 12 bytes
> 
> - fix bug in zynqmp-ipi isr handling
>   Multiple IPI channels are mapped to same interrupt handler.
>   Current isr implementation handles only one channel per isr.
>   Fix this behavior by checking isr status bit of all child
>   mailbox nodes.
> 
> Fixes: 4981b82ba2ff ("mailbox: ZynqMP IPI mailbox controller")
> Signed-off-by: Tanmay Shah <tanmay.shah@amd.com>
> ---
> 
> Changelog:
>   - This is first version of this change, however posting as part of the series
>     that has version v3.
> 
> v2: https://lore.kernel.org/all/20230126213154.1707300-1-tanmay.shah@amd.com/
> 
>  drivers/mailbox/zynqmp-ipi-mailbox.c       | 8 ++++----
>  include/linux/mailbox/zynqmp-ipi-message.h | 2 +-
>  2 files changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/mailbox/zynqmp-ipi-mailbox.c b/drivers/mailbox/zynqmp-ipi-mailbox.c
> index 12e004ff1a14..b1498f6f06e1 100644
> --- a/drivers/mailbox/zynqmp-ipi-mailbox.c
> +++ b/drivers/mailbox/zynqmp-ipi-mailbox.c
> @@ -152,7 +152,7 @@ static irqreturn_t zynqmp_ipi_interrupt(int irq, void *data)
>  	struct zynqmp_ipi_message *msg;
>  	u64 arg0, arg3;
>  	struct arm_smccc_res res;
> -	int ret, i;
> +	int ret, i, status = IRQ_NONE;
>  
>  	(void)irq;
>  	arg0 = SMC_IPI_MAILBOX_STATUS_ENQUIRY;
> @@ -170,11 +170,11 @@ static irqreturn_t zynqmp_ipi_interrupt(int irq, void *data)
>  				memcpy_fromio(msg->data, mchan->req_buf,
>  					      msg->len);
>  				mbox_chan_received_data(chan, (void *)msg);
> -				return IRQ_HANDLED;
> +				status = IRQ_HANDLED;
>  			}
>  		}
>  	}
> -	return IRQ_NONE;
> +	return status;
>  }
>  
>  /**
> @@ -634,7 +634,7 @@ static int zynqmp_ipi_probe(struct platform_device *pdev)
>  	struct zynqmp_ipi_mbox *mbox;
>  	int num_mboxes, ret = -EINVAL;
>  
> -	num_mboxes = of_get_child_count(np);
> +	num_mboxes = of_get_available_child_count(np);
>  	pdata = devm_kzalloc(dev, sizeof(*pdata) + (num_mboxes * sizeof(*mbox)),
>  			     GFP_KERNEL);
>  	if (!pdata)
> diff --git a/include/linux/mailbox/zynqmp-ipi-message.h b/include/linux/mailbox/zynqmp-ipi-message.h
> index 35ce84c8ca02..31d8046d945e 100644
> --- a/include/linux/mailbox/zynqmp-ipi-message.h
> +++ b/include/linux/mailbox/zynqmp-ipi-message.h
> @@ -9,7 +9,7 @@
>   * @data: message payload
>   *
>   * This is the structure for data used in mbox_send_message
> - * the maximum length of data buffer is fixed to 12 bytes.
> + * the maximum length of data buffer is fixed to 32 bytes.
>   * Client is supposed to be aware of this.

I agree that this should be split in 3 patches but the fixes are so small that
it is hardly required.  I'll leave it up to Michal to decide.

Split or not:

Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>

>   */
>  struct zynqmp_ipi_message {
> -- 
> 2.25.1
>