From: Alexandre Courbot <[email protected]>
When running memcpy_toio:
memcpy_toio(send_obj->share_buf, buf, len);
it was found that errors appear if len is not a multiple of 8:
[58.350841] mtk-mdp 14001000.rdma: processing failed: -22
This is because in ARM64, memcpy_toio does byte-size access
when the length is not a multiple of 8 while access to the
vpu iomem must be 4 aligned.
This patch ensures the copy of a multiple of 8 size by calling
round_up(len, 8) when copying.
Fixes: e6599adfad30 ("media: mtk-vpu: avoid unaligned access to DTCM buffer.")
Signed-off-by: Alexandre Courbot <[email protected]>
Signed-off-by: Dafna Hirschfeld <[email protected]>
Signed-off-by: Pin-yen Lin <[email protected]>
Reviewed-by: Houlong Wei <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
---
This is a re-send of v5 because it was marked obsolete, but this patch
is required for MT8173 platforms.
Changes in v6:
- Collect review tag
drivers/media/platform/mediatek/vpu/mtk_vpu.c | 17 ++++++++++++++++-
1 file changed, 16 insertions(+), 1 deletion(-)
diff --git a/drivers/media/platform/mediatek/vpu/mtk_vpu.c b/drivers/media/platform/mediatek/vpu/mtk_vpu.c
index 5e2bc286f168..19ff4afea456 100644
--- a/drivers/media/platform/mediatek/vpu/mtk_vpu.c
+++ b/drivers/media/platform/mediatek/vpu/mtk_vpu.c
@@ -349,7 +349,22 @@ int vpu_ipi_send(struct platform_device *pdev,
}
} while (vpu_cfg_readl(vpu, HOST_TO_VPU));
- memcpy_toio(send_obj->share_buf, buf, len);
+ /*
+ * On Arm64, the memcpy_toio does byte-size access as long as address or length are
+ * not 8 aligned. Access to the vpu iomem must be 4 aligned. Byte-size access is
+ * not allowed and cause processing to fail. Therefore make sure the length
+ * sent to memcpy_toio is a multiply of 8.
+ */
+ if (len % 8 != 0) {
+ unsigned char data[sizeof(send_obj->share_buf)];
+
+ memset(data + len, 0, sizeof(data) - len);
+ memcpy(data, buf, len);
+ memcpy_toio(send_obj->share_buf, data, round_up(len, 8));
+ } else {
+ memcpy_toio(send_obj->share_buf, buf, len);
+ }
+
writel(len, &send_obj->len);
writel(id, &send_obj->id);
--
2.41.0.rc0.172.g3f132b7071-goog
Il 26/05/23 08:31, Pin-yen Lin ha scritto:
> From: Alexandre Courbot <[email protected]>
>
> When running memcpy_toio:
> memcpy_toio(send_obj->share_buf, buf, len);
> it was found that errors appear if len is not a multiple of 8:
>
> [58.350841] mtk-mdp 14001000.rdma: processing failed: -22
>
> This is because in ARM64, memcpy_toio does byte-size access
> when the length is not a multiple of 8 while access to the
> vpu iomem must be 4 aligned.
>
> This patch ensures the copy of a multiple of 8 size by calling
> round_up(len, 8) when copying.
>
> Fixes: e6599adfad30 ("media: mtk-vpu: avoid unaligned access to DTCM buffer.")
> Signed-off-by: Alexandre Courbot <[email protected]>
> Signed-off-by: Dafna Hirschfeld <[email protected]>
> Signed-off-by: Pin-yen Lin <[email protected]>
> Reviewed-by: Houlong Wei <[email protected]>
> Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
>
> ---
> This is a re-send of v5 because it was marked obsolete, but this patch
> is required for MT8173 platforms.
>
Hello,
I have solved this issue in a different way and the commit was already picked.
Please check:
ab14c99c035d ("media: platform: mtk-mdp: Fix mdp_ipi_comm structure alignment")
Regards,
Angelo
Hi Angelo,
Thanks for letting me know. Then, this patch is not needed.
Regards,
Pin-yen
On Mon, May 29, 2023 at 4:31 PM AngeloGioacchino Del Regno
<[email protected]> wrote:
>
> Il 26/05/23 08:31, Pin-yen Lin ha scritto:
> > From: Alexandre Courbot <[email protected]>
> >
> > When running memcpy_toio:
> > memcpy_toio(send_obj->share_buf, buf, len);
> > it was found that errors appear if len is not a multiple of 8:
> >
> > [58.350841] mtk-mdp 14001000.rdma: processing failed: -22
> >
> > This is because in ARM64, memcpy_toio does byte-size access
> > when the length is not a multiple of 8 while access to the
> > vpu iomem must be 4 aligned.
> >
> > This patch ensures the copy of a multiple of 8 size by calling
> > round_up(len, 8) when copying.
> >
> > Fixes: e6599adfad30 ("media: mtk-vpu: avoid unaligned access to DTCM buffer.")
> > Signed-off-by: Alexandre Courbot <[email protected]>
> > Signed-off-by: Dafna Hirschfeld <[email protected]>
> > Signed-off-by: Pin-yen Lin <[email protected]>
> > Reviewed-by: Houlong Wei <[email protected]>
> > Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
> >
> > ---
> > This is a re-send of v5 because it was marked obsolete, but this patch
> > is required for MT8173 platforms.
> >
>
> Hello,
> I have solved this issue in a different way and the commit was already picked.
>
> Please check:
> ab14c99c035d ("media: platform: mtk-mdp: Fix mdp_ipi_comm structure alignment")
>
> Regards,
> Angelo
>