2023-11-27 12:46:32

by Manivannan Sadhasivam

Subject: [PATCH 4/9] PCI: epf-mhi: Simulate async read/write using iATU

Even though iATU only supports synchronous read/write, the MHI stack may
call async read/write callbacks without knowing the limitations of the
controller driver. So in order to maintain compatibility, let's simulate
async read/write operation with iATU by invoking the completion callback
after memcpy.

Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
drivers/pci/endpoint/functions/pci-epf-mhi.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 34e7191f9508..7214f4da733b 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -234,6 +234,9 @@ static int pci_epf_mhi_iatu_read(struct mhi_ep_cntrl *mhi_cntrl,

mutex_unlock(&epf_mhi->lock);

+ if (buf_info->cb)
+ buf_info->cb(buf_info);
+
return 0;
}

@@ -262,6 +265,9 @@ static int pci_epf_mhi_iatu_write(struct mhi_ep_cntrl *mhi_cntrl,

mutex_unlock(&epf_mhi->lock);

+ if (buf_info->cb)
+ buf_info->cb(buf_info);
+
return 0;
}

--
2.25.1

2023-12-13 18:49:46

by Krzysztof Wilczyński

Subject: Re: [PATCH 4/9] PCI: epf-mhi: Simulate async read/write using iATU

Hello,

> Even though iATU only supports synchronous read/write, the MHI stack may
> call async read/write callbacks without knowing the limitations of the
> controller driver. So in order to maintain compatibility, let's simulate
> async read/write operation with iATU by invoking the completion callback
> after memcpy.
>
> Signed-off-by: Manivannan Sadhasivam <[email protected]>
> ---
> drivers/pci/endpoint/functions/pci-epf-mhi.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
> index 34e7191f9508..7214f4da733b 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
> @@ -234,6 +234,9 @@ static int pci_epf_mhi_iatu_read(struct mhi_ep_cntrl *mhi_cntrl,
>
> mutex_unlock(&epf_mhi->lock);
>
> + if (buf_info->cb)
> + buf_info->cb(buf_info);
> +
> return 0;
> }
>
> @@ -262,6 +265,9 @@ static int pci_epf_mhi_iatu_write(struct mhi_ep_cntrl *mhi_cntrl,
>
> mutex_unlock(&epf_mhi->lock);
>
> + if (buf_info->cb)
> + buf_info->cb(buf_info);
> +
> return 0;
> }

Looks good!

Reviewed-by: Krzysztof Wilczyński <[email protected]>

Krzysztof