> Subject: Re: [PATCH V3 7/7] remoteproc: imx_proc: enable virtio/mailbox
>
> On Fri 04 Dec 01:40 CST 2020, Peng Fan (OSS) wrote:
>
> > From: Peng Fan <peng.fan@xxxxxxx>
> >
> > Use virtio/mailbox to build connection between Remote Proccessors and
> > Linux. Add work queue to handle incoming messages.
> >
> > Reviewed-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> > ---
> > drivers/remoteproc/imx_rproc.c | 133
> > ++++++++++++++++++++++++++++++++-
> > 1 file changed, 130 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/remoteproc/imx_rproc.c
> > b/drivers/remoteproc/imx_rproc.c index afa650610996..584584a00921
> > 100644
> > --- a/drivers/remoteproc/imx_rproc.c
> > +++ b/drivers/remoteproc/imx_rproc.c
> > @@ -8,6 +8,7 @@
> > #include <linux/interrupt.h>
> > #include <linux/io.h>
> > #include <linux/kernel.h>
> > +#include <linux/mailbox_client.h>
> > #include <linux/mfd/syscon.h>
> > #include <linux/module.h>
> > #include <linux/of_address.h>
> > @@ -16,6 +17,9 @@
> > #include <linux/platform_device.h>
> > #include <linux/regmap.h>
> > #include <linux/remoteproc.h>
> > +#include <linux/workqueue.h>
> > +
> > +#include "remoteproc_internal.h"
> >
> > #define IMX7D_SRC_SCR 0x0C
> > #define IMX7D_ENABLE_M4 BIT(3)
> > @@ -88,6 +92,11 @@ struct imx_rproc {
> > const struct imx_rproc_dcfg *dcfg;
> > struct imx_rproc_mem mem[IMX7D_RPROC_MEM_MAX];
> > struct clk *clk;
> > + struct mbox_client cl;
> > + struct mbox_chan *tx_ch;
> > + struct mbox_chan *rx_ch;
> > + struct work_struct rproc_work;
> > + struct workqueue_struct *workqueue;
> > };
> >
> > static const struct imx_rproc_att imx_rproc_att_imx8mq[] = { @@
> > -369,9 +378,33 @@ static int imx_rproc_parse_fw(struct rproc *rproc,
> const struct firmware *fw)
> > return 0;
> > }
> >
> > +static void imx_rproc_kick(struct rproc *rproc, int vqid) {
> > + struct imx_rproc *priv = rproc->priv;
> > + int err;
> > + __u32 mmsg;
> > +
> > + if (!priv->tx_ch) {
> > + dev_err(priv->dev, "No initialized mbox tx channel\n");
> > + return;
> > + }
> > +
> > + /*
> > + * Send the index of the triggered virtqueue as the mu payload.
> > + * Let remote processor know which virtqueue is used.
> > + */
> > + mmsg = vqid << 16;
> > +
> > + err = mbox_send_message(priv->tx_ch, (void *)&mmsg);
> > + if (err < 0)
> > + dev_err(priv->dev, "%s: failed (%d, err:%d)\n",
> > + __func__, vqid, err);
> > +}
> > +
> > static const struct rproc_ops imx_rproc_ops = {
> > .start = imx_rproc_start,
> > .stop = imx_rproc_stop,
> > + .kick = imx_rproc_kick,
> > .da_to_va = imx_rproc_da_to_va,
> > .load = rproc_elf_load_segments,
> > .parse_fw = imx_rproc_parse_fw,
> > @@ -454,6 +487,77 @@ static void imx_rproc_memset(struct rproc *rproc,
> void *s, int c, size_t count)
> > memset_io((void * __iomem)s, c, count); }
> >
> > +static void imx_rproc_vq_work(struct work_struct *work) {
> > + struct imx_rproc *priv = container_of(work, struct imx_rproc,
> > + rproc_work);
> > +
> > + rproc_vq_interrupt(priv->rproc, 0);
> > + rproc_vq_interrupt(priv->rproc, 1);
> > +}
> > +
> > +static void imx_rproc_rx_callback(struct mbox_client *cl, void *msg)
> > +{
> > + struct rproc *rproc = dev_get_drvdata(cl->dev);
> > + struct imx_rproc *priv = rproc->priv;
> > +
> > + queue_work(priv->workqueue, &priv->rproc_work); }
> > +
> > +static int imx_rproc_xtr_mbox_init(struct rproc *rproc) {
> > + struct imx_rproc *priv = rproc->priv;
> > + struct device *dev = priv->dev;
> > + struct mbox_client *cl;
> > + int ret = 0;
> > +
> > + if (!of_get_property(dev->of_node, "mbox-names", NULL))
> > + return 0;
> > +
> > + cl = &priv->cl;
> > + cl->dev = dev;
> > + cl->tx_block = true;
> > + cl->tx_tout = 100;
> > + cl->knows_txdone = false;
> > + cl->rx_callback = imx_rproc_rx_callback;
> > +
> > + priv->tx_ch = mbox_request_channel_byname(cl, "tx");
> > + if (IS_ERR(priv->tx_ch)) {
> > + if (PTR_ERR(priv->tx_ch) == -EPROBE_DEFER)
> > + return -EPROBE_DEFER;
> > + ret = PTR_ERR(priv->tx_ch);
> > + dev_dbg(cl->dev, "failed to request mbox tx chan, ret %d\n",
> > + ret);
>
> This is worse than a dev_dbg(), something is actually wrong.
> Also there's no point in jumping to err_out here, because tx_ch is
> IS_ERR() so we're going to skip the first part and rx_ch is not IS_ERR() so
> you're going to call mbox_free_channel(NULL) and then return.
>
> So just replace this entire block with:
>
> return dev_err_probe(dev, PTR_ERR(priv->ch_ch),
> "failed to request tx mailbox channel: %d\n",
> ret);
Yeah. Thanks.
>
>
> > + goto err_out;
> > + }
> > +
> > + priv->rx_ch = mbox_request_channel_byname(cl, "rx");
> > + if (IS_ERR(priv->rx_ch)) {
> > + ret = PTR_ERR(priv->rx_ch);
> > + dev_dbg(cl->dev, "failed to request mbox rx chan, ret %d\n",
> > + ret);
> > + goto err_out;
>
> mbox_free_channel(priv->tx_ch);
> return dev_err_probe(dev, PTR_ERR(priv->ch_ch),
> "failed to request rx mailbox channel: %d\n",
> ret);
>
> > + }
> > +
> > + return ret;
>
> ret is 0 here.
Yes.
>
> > +
> > +err_out:
> > + if (!IS_ERR(priv->tx_ch))
> > + mbox_free_channel(priv->tx_ch);
> > + if (!IS_ERR(priv->rx_ch))
> > + mbox_free_channel(priv->rx_ch);
> > +
> > + return ret;
> > +}
> > +
> > +static void imx_rproc_free_mbox(struct rproc *rproc) {
> > + struct imx_rproc *priv = rproc->priv;
> > +
> > + mbox_free_channel(priv->tx_ch);
> > + mbox_free_channel(priv->rx_ch);
> > +}
> > +
> > static int imx_rproc_probe(struct platform_device *pdev) {
> > struct device *dev = &pdev->dev;
> > @@ -496,18 +600,31 @@ static int imx_rproc_probe(struct
> platform_device *pdev)
> > priv->dev = dev;
> >
> > dev_set_drvdata(dev, rproc);
> > + priv->workqueue = create_workqueue(dev_name(dev));
> > + if (!priv->workqueue) {
> > + dev_err(dev, "cannot create workqueue\n");
> > + ret = -ENOMEM;
> > + goto err_put_rproc;
> > + }
> > +
> > + ret = imx_rproc_xtr_mbox_init(rproc);
> > + if (ret) {
> > + if (ret == -EPROBE_DEFER)
> > + goto err_put_wkq;
> > + /* mbox is optional, so not fail here */
>
> imx_rproc_xtr_mbox_init() returns 0 if no mbox was specified, that means
> that in all cases that we reach here mailboxes where specified but an error
> occurred. You should not ignore this.
ok, fix in v4.
>
> > + }
> >
> > ret = imx_rproc_addr_init(priv, pdev);
> > if (ret) {
> > dev_err(dev, "failed on imx_rproc_addr_init\n");
> > - goto err_put_rproc;
> > + goto err_put_mbox;
> > }
> >
> > priv->clk = devm_clk_get(dev, NULL);
> > if (IS_ERR(priv->clk)) {
> > dev_err(dev, "Failed to get clock\n");
> > ret = PTR_ERR(priv->clk);
> > - goto err_put_rproc;
> > + goto err_put_mbox;
> > }
> >
> > /*
> > @@ -517,9 +634,11 @@ static int imx_rproc_probe(struct platform_device
> *pdev)
> > ret = clk_prepare_enable(priv->clk);
> > if (ret) {
> > dev_err(&rproc->dev, "Failed to enable clock\n");
> > - goto err_put_rproc;
> > + goto err_put_mbox;
> > }
> >
> > + INIT_WORK(&(priv->rproc_work), imx_rproc_vq_work);
> > +
> > ret = rproc_add(rproc);
> > if (ret) {
> > dev_err(dev, "rproc_add failed\n"); @@ -530,6 +649,13 @@ static
> int
> > imx_rproc_probe(struct platform_device *pdev)
> >
> > err_put_clk:
> > clk_disable_unprepare(priv->clk);
> > +err_put_mbox:
> > + if (!IS_ERR(priv->tx_ch))
>
> With above changes you won't get here with IS_ERR(tx_ch) || IS_ERR(rx_ch),
> so you can safely remove the conditionals and just call mbox_free_channel().
Yes.
After we agree on the new method of patch 1/7, I'll post out v4.
Thanks,
Peng.
>
> Regards,
> Bjorn
>
> > + mbox_free_channel(priv->tx_ch);
> > + if (!IS_ERR(priv->rx_ch))
> > + mbox_free_channel(priv->rx_ch);
> > +err_put_wkq:
> > + destroy_workqueue(priv->workqueue);
> > err_put_rproc:
> > rproc_free(rproc);
> >
> > @@ -542,6 +668,7 @@ static int imx_rproc_remove(struct platform_device
> *pdev)
> > struct imx_rproc *priv = rproc->priv;
> >
> > clk_disable_unprepare(priv->clk);
> > + imx_rproc_free_mbox(rproc);
> > rproc_del(rproc);
> > rproc_free(rproc);
> >
> > --
> > 2.28.0
> >
