Re: [PATCH 2/2] mhi: pci_generic: Fix shared MSI vector support

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

On Tue, Jan 05, 2021 at 09:56:15AM +0100, Loic Poulain wrote:
> When a shared MSI vector must be used (e.g. when VTd is disabled on
> x86_64), each event MSI vector must be set to the shared vector idx.
> 
> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
> ---
>  drivers/bus/mhi/pci_generic.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c
> index 86ff0c3..23ef585 100644
> --- a/drivers/bus/mhi/pci_generic.c
> +++ b/drivers/bus/mhi/pci_generic.c
> @@ -154,7 +154,7 @@ static const struct mhi_channel_config modem_qcom_v1_mhi_channels[] = {
>  	MHI_CHANNEL_CONFIG_HW_DL(101, "IP_HW0", 128, 3),
>  };
>  
> -static const struct mhi_event_config modem_qcom_v1_mhi_events[] = {
> +static struct mhi_event_config modem_qcom_v1_mhi_events[] = {
>  	/* first ring is control+data ring */
>  	MHI_EVENT_CONFIG_CTRL(0),
>  	/* DIAG dedicated event ring */
> @@ -164,7 +164,7 @@ static const struct mhi_event_config modem_qcom_v1_mhi_events[] = {
>  	MHI_EVENT_CONFIG_HW_DATA(3, 101)
>  };
>  
> -static const struct mhi_controller_config modem_qcom_v1_mhiv_config = {
> +static struct mhi_controller_config modem_qcom_v1_mhiv_config = {
>  	.max_channels = 128,
>  	.timeout_ms = 8000,
>  	.num_channels = ARRAY_SIZE(modem_qcom_v1_mhi_channels),
> @@ -297,6 +297,11 @@ static int mhi_pci_get_irqs(struct mhi_controller *mhi_cntrl,
>  	if (nr_vectors < mhi_cntrl->nr_irqs) {
>  		dev_warn(&pdev->dev, "Not enough MSI vectors (%d/%d), use shared MSI\n",

So now the log should say, "using shared MSI"! with that,

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Thanks,
Mani

>  			 nr_vectors, mhi_cntrl_config->num_events);
> +
> +		/* Patch msi vectors, use only one (shared) */
> +		for (i = 0; i < mhi_cntrl_config->num_events; i++)
> +			mhi_cntrl_config->event_cfg[i].irq = 0;
> +		mhi_cntrl->nr_irqs = 1;
>  	}
>  
>  	irq = devm_kcalloc(&pdev->dev, mhi_cntrl->nr_irqs, sizeof(int), GFP_KERNEL);
> -- 
> 2.7.4
>