[PATCH v3 3/3] remoteproc: xilinx: add mailbox channels for rpmsg
Mathieu Poirier
mathieu.poirier at linaro.org
Wed Feb 22 11:06:23 PST 2023
On Mon, Feb 13, 2023 at 01:18:26PM -0800, Tanmay Shah wrote:
> This patch makes each r5 core mailbox client and uses
> tx and rx channels to send and receive data to/from
> remote processor respectively. This is needed for rpmsg
> communication to remote processor.
>
> Signed-off-by: Tanmay Shah <tanmay.shah at amd.com>
> ---
>
> Changes in v3:
> - fix multi-line comment format
> - do not mixup mailbox information with memory-regions
> - fix redundant dev_warn for split mode
> - setting up mailboxes should return an error code
> - redesign driver to move mailbox setup during driver probe
> - add .kick function only if mailbox setup is success
>
> v2: https://lore.kernel.org/all/20230126213154.1707300-1-tanmay.shah@amd.com/
>
> drivers/remoteproc/xlnx_r5_remoteproc.c | 228 +++++++++++++++++++++++-
> 1 file changed, 226 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/xlnx_r5_remoteproc.c b/drivers/remoteproc/xlnx_r5_remoteproc.c
> index 81af2dea56c2..f7131fe8fe7e 100644
> --- a/drivers/remoteproc/xlnx_r5_remoteproc.c
> +++ b/drivers/remoteproc/xlnx_r5_remoteproc.c
> @@ -8,16 +8,23 @@
> #include <linux/dma-mapping.h>
> #include <linux/firmware/xlnx-zynqmp.h>
> #include <linux/kernel.h>
> +#include <linux/mailbox_client.h>
> +#include <linux/mailbox/zynqmp-ipi-message.h>
> #include <linux/module.h>
> #include <linux/of_address.h>
> #include <linux/of_platform.h>
> #include <linux/of_reserved_mem.h>
> #include <linux/platform_device.h>
> #include <linux/remoteproc.h>
> -#include <linux/slab.h>
>
> #include "remoteproc_internal.h"
>
> +/* IPI buffer MAX length */
> +#define IPI_BUF_LEN_MAX 32U
> +
> +/* RX mailbox client buffer max length */
> +#define MBOX_CLIENT_BUF_MAX (IPI_BUF_LEN_MAX + \
> + sizeof(struct zynqmp_ipi_message))
> /*
> * settings for RPU cluster mode which
> * reflects possible values of xlnx,cluster-mode dt-property
> @@ -43,6 +50,27 @@ struct mem_bank_data {
> char *bank_name;
> };
>
> +/**
> + * struct mbox_info
> + *
> + * @rx_mc_buf: to copy data from mailbox rx channel
> + * @tx_mc_buf: to copy data to mailbox tx channel
> + * @r5_core: this mailbox's corresponding r5_core pointer
> + * @mbox_work: schedule work after receiving data from mailbox
> + * @mbox_cl: mailbox client
> + * @tx_chan: mailbox tx channel
> + * @rx_chan: mailbox rx channel
> + */
> +struct mbox_info {
> + unsigned char rx_mc_buf[MBOX_CLIENT_BUF_MAX];
> + unsigned char tx_mc_buf[MBOX_CLIENT_BUF_MAX];
> + struct zynqmp_r5_core *r5_core;
> + struct work_struct mbox_work;
> + struct mbox_client mbox_cl;
> + struct mbox_chan *tx_chan;
> + struct mbox_chan *rx_chan;
> +};
> +
> /*
> * Hardcoded TCM bank values. This will be removed once TCM bindings are
> * accepted for system-dt specifications and upstreamed in linux kernel
> @@ -63,6 +91,7 @@ static const struct mem_bank_data zynqmp_tcm_banks[] = {
> * @tcm_banks: array of each TCM bank data
> * @rproc: rproc handle
> * @pm_domain_id: RPU CPU power domain id
> + * @ipi: pointer to mailbox information
> */
> struct zynqmp_r5_core {
> struct device *dev;
> @@ -71,6 +100,7 @@ struct zynqmp_r5_core {
> struct mem_bank_data **tcm_banks;
> struct rproc *rproc;
> u32 pm_domain_id;
> + struct mbox_info *ipi;
> };
>
> /**
> @@ -88,6 +118,178 @@ struct zynqmp_r5_cluster {
> struct zynqmp_r5_core **r5_cores;
> };
>
> +/**
> + * event_notified_idr_cb() - callback for vq_interrupt per notifyid
> + * @id: rproc->notify id
> + * @ptr: pointer to idr private data
> + * @data: data passed to idr_for_each callback
> + *
> + * Pass notification to remoteproc virtio
> + *
> + * Return: 0. having return is to satisfy the idr_for_each() function
> + * pointer input argument requirement.
> + **/
> +static int event_notified_idr_cb(int id, void *ptr, void *data)
> +{
> + struct rproc *rproc = data;
> +
> + if (rproc_vq_interrupt(rproc, id) == IRQ_NONE)
> + dev_dbg(&rproc->dev, "data not found for vqid=%d\n", id);
> +
> + return 0;
> +}
> +
> +/**
> + * handle_event_notified() - remoteproc notification work function
> + * @work: pointer to the work structure
> + *
> + * It checks each registered remoteproc notify IDs.
> + */
> +static void handle_event_notified(struct work_struct *work)
> +{
> + struct mbox_info *ipi;
> + struct rproc *rproc;
> +
> + ipi = container_of(work, struct mbox_info, mbox_work);
> + rproc = ipi->r5_core->rproc;
> +
> + /*
> + * We only use IPI for interrupt. The RPU firmware side may or may
> + * not write the notifyid when it trigger IPI.
> + * And thus, we scan through all the registered notifyids and
> + * find which one is valid to get the message.
> + * Even if message from firmware is NULL, we attempt to get vqid
> + */
> + idr_for_each(&rproc->notifyids, event_notified_idr_cb, rproc);
> +}
> +
> +/**
> + * zynqmp_r5_mb_rx_cb() - receive channel mailbox callback
> + * @cl: mailbox client
> + * @msg: message pointer
> + *
> + * Receive data from ipi buffer, ack interrupt and then
> + * it will schedule the R5 notification work.
> + */
> +static void zynqmp_r5_mb_rx_cb(struct mbox_client *cl, void *msg)
> +{
> + struct zynqmp_ipi_message *ipi_msg, *buf_msg;
> + struct mbox_info *ipi;
> + size_t len;
> +
> + ipi = container_of(cl, struct mbox_info, mbox_cl);
> +
> + /* copy data from ipi buffer to r5_core */
> + ipi_msg = (struct zynqmp_ipi_message *)msg;
> + buf_msg = (struct zynqmp_ipi_message *)ipi->rx_mc_buf;
> + len = ipi_msg->len;
> + if (len > IPI_BUF_LEN_MAX) {
> + dev_warn(cl->dev, "msg size exceeded than %d\n",
> + IPI_BUF_LEN_MAX);
> + len = IPI_BUF_LEN_MAX;
> + }
> + buf_msg->len = len;
> + memcpy(buf_msg->data, ipi_msg->data, len);
> +
> + /* received and processed interrupt ack */
> + if (mbox_send_message(ipi->rx_chan, NULL) < 0)
> + dev_err(cl->dev, "ack failed to mbox rx_chan\n");
> +
> + schedule_work(&ipi->mbox_work);
> +}
> +
> +/**
> + * zynqmp_r5_setup_mbox() - Setup mailboxes related properties
> + * this is used for each individual R5 core
> + *
> + * @cdev: child node device
> + *
> + * Function to setup mailboxes related properties
> + * return : NULL if failed else pointer to mbox_info
> + */
> +static struct mbox_info *zynqmp_r5_setup_mbox(struct device *cdev)
> +{
> + struct mbox_client *mbox_cl;
> + struct mbox_info *ipi;
> +
> + ipi = kzalloc(sizeof(*ipi), GFP_KERNEL);
> + if (!ipi)
> + return NULL;
> +
> + mbox_cl = &ipi->mbox_cl;
> + mbox_cl->rx_callback = zynqmp_r5_mb_rx_cb;
> + mbox_cl->tx_block = false;
> + mbox_cl->knows_txdone = false;
> + mbox_cl->tx_done = NULL;
> + mbox_cl->dev = cdev;
> +
> + /* Request TX and RX channels */
> + ipi->tx_chan = mbox_request_channel_byname(mbox_cl, "tx");
> + if (IS_ERR(ipi->tx_chan)) {
> + ipi->tx_chan = NULL;
> + kfree(ipi);
> + dev_warn(cdev, "mbox tx channel request failed\n");
> + return NULL;
> + }
> +
> + ipi->rx_chan = mbox_request_channel_byname(mbox_cl, "rx");
> + if (IS_ERR(ipi->rx_chan)) {
> + mbox_free_channel(ipi->tx_chan);
> + ipi->rx_chan = NULL;
> + ipi->tx_chan = NULL;
> + kfree(ipi);
> + dev_warn(cdev, "mbox rx channel request failed\n");
> + return NULL;
> + }
> +
> + INIT_WORK(&ipi->mbox_work, handle_event_notified);
> +
> + return ipi;
> +}
> +
> +static void zynqmp_r5_free_mbox(struct mbox_info *ipi)
> +{
> + if (!ipi)
> + return;
> +
> + if (ipi->tx_chan) {
> + mbox_free_channel(ipi->tx_chan);
> + ipi->tx_chan = NULL;
> + }
> +
> + if (ipi->rx_chan) {
> + mbox_free_channel(ipi->rx_chan);
> + ipi->rx_chan = NULL;
> + }
> +
> + kfree(ipi);
> +}
> +
> +/*
> + * zynqmp_r5_core_kick() - kick a firmware if mbox is provided
> + * @rproc: r5 core's corresponding rproc structure
> + * @vqid: virtqueue ID
> + */
> +static void zynqmp_r5_rproc_kick(struct rproc *rproc, int vqid)
> +{
> + struct zynqmp_r5_core *r5_core = rproc->priv;
> + struct device *dev = r5_core->dev;
> + struct zynqmp_ipi_message *mb_msg;
> + struct mbox_info *ipi;
> + int ret;
> +
> + ipi = r5_core->ipi;
> + if (!ipi)
> + return;
> +
> + mb_msg = (struct zynqmp_ipi_message *)ipi->tx_mc_buf;
> + memcpy(mb_msg->data, &vqid, sizeof(vqid));
> + mb_msg->len = sizeof(vqid);
> + ret = mbox_send_message(ipi->tx_chan, mb_msg);
> + if (ret < 0)
> + dev_warn(dev, "failed to send message\n");
> +}
> +
> /*
> * zynqmp_r5_set_mode()
> *
> @@ -617,7 +819,7 @@ static int zynqmp_r5_rproc_unprepare(struct rproc *rproc)
> return 0;
> }
>
> -static const struct rproc_ops zynqmp_r5_rproc_ops = {
> +static struct rproc_ops zynqmp_r5_rproc_ops = {
> .prepare = zynqmp_r5_rproc_prepare,
> .unprepare = zynqmp_r5_rproc_unprepare,
> .start = zynqmp_r5_rproc_start,
> @@ -642,6 +844,7 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
> {
> struct zynqmp_r5_core *r5_core;
> struct rproc *r5_rproc;
> + struct mbox_info *ipi;
> int ret;
>
> /* Set up DMA mask */
> @@ -649,12 +852,23 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
> if (ret)
> return ERR_PTR(ret);
>
> + /*
> + * If mailbox nodes are disabled using "status" property then setting up
> + * mailbox channels will be failed. In that case we don't really need
> + * kick() operation. Include .kick() only if mbox channels are acquired
> + * successfully.
> + */
> + ipi = zynqmp_r5_setup_mbox(cdev);
> + if (ipi)
> + zynqmp_r5_rproc_ops.kick = zynqmp_r5_rproc_kick;
> +
> /* Allocate remoteproc instance */
> r5_rproc = rproc_alloc(cdev, dev_name(cdev),
> &zynqmp_r5_rproc_ops,
> NULL, sizeof(struct zynqmp_r5_core));
> if (!r5_rproc) {
> dev_err(cdev, "failed to allocate memory for rproc instance\n");
> + zynqmp_r5_free_mbox(ipi);
> return ERR_PTR(-ENOMEM);
> }
>
> @@ -665,6 +879,7 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
> if (!r5_core->np) {
> dev_err(cdev, "can't get device node for r5 core\n");
> ret = -EINVAL;
> + zynqmp_r5_free_mbox(ipi);
> goto free_rproc;
> }
>
> @@ -672,10 +887,17 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
> ret = rproc_add(r5_rproc);
> if (ret) {
> dev_err(cdev, "failed to add r5 remoteproc\n");
> + zynqmp_r5_free_mbox(ipi);
> goto free_rproc;
> }
>
> + if (ipi) {
> + r5_core->ipi = ipi;
> + ipi->r5_core = r5_core;
> + }
> +
> r5_core->rproc = r5_rproc;
> +
> return r5_core;
>
> free_rproc:
> @@ -918,6 +1140,7 @@ static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
> while (i >= 0) {
> put_device(child_devs[i]);
> if (r5_cores[i]) {
> + zynqmp_r5_free_mbox(r5_cores[i]->ipi);
The mailboxes are initialized in zynqmp_r5_add_rproc_core() but free'd here in
case of trouble, which introduces coupling between the two functions. I suggest
moving zynqmp_r5_setup_mbox() in zynqmp_r5_cluster_init() and initialize both
mailboxes in it.
I am done reviewing this set.
Thanks,
Mathieu
Thanks,
Mathieu
> of_reserved_mem_device_release(r5_cores[i]->dev);
> rproc_del(r5_cores[i]->rproc);
> rproc_free(r5_cores[i]->rproc);
> @@ -942,6 +1165,7 @@ static void zynqmp_r5_cluster_exit(void *data)
>
> for (i = 0; i < cluster->core_count; i++) {
> r5_core = cluster->r5_cores[i];
> + zynqmp_r5_free_mbox(r5_core->ipi);
> of_reserved_mem_device_release(r5_core->dev);
> put_device(r5_core->dev);
> rproc_del(r5_core->rproc);
> --
> 2.25.1
>
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