Re: [PATCH v4 5/5] remoteproc: xilinx: add mailbox channels for rpmsg
From: Tanmay Shah
Date: Fri Mar 03 2023 - 11:37:04 EST
On 3/2/23 5:10 PM, Mathieu Poirier wrote:
Hi,
On Tue, Feb 28, 2023 at 01:02:16PM -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@xxxxxxx>
---
Changes in v4:
- move zynqmp_r5_setup_mbox from zynqmp_r5_add_rproc_core to
zynqmp_r5_cluster_init
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@xxxxxxx/
drivers/remoteproc/xlnx_r5_remoteproc.c | 227 +++++++++++++++++++++++-
1 file changed, 225 insertions(+), 2 deletions(-)
diff --git a/drivers/remoteproc/xlnx_r5_remoteproc.c b/drivers/remoteproc/xlnx_r5_remoteproc.c
index 5dd007622603..78c1638ccef0 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()
*
@@ -614,7 +816,7 @@ 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,
@@ -673,6 +875,7 @@ static struct zynqmp_r5_core *zynqmp_r5_add_rproc_core(struct device *cdev)
}
r5_core->rproc = r5_rproc;
+
Spurious change.
Ack will remove it.
return r5_core;
free_rproc:
@@ -799,6 +1002,7 @@ static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
struct device_node *child;
enum rpu_tcm_comb tcm_mode;
int core_count, ret, i;
+ struct mbox_info *ipi;
ret = of_property_read_u32(dev_node, "xlnx,cluster-mode", &cluster_mode);
@@ -869,6 +1073,18 @@ static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
child_devs[i] = &child_pdev->dev;
+ /*
+ * 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(&child_pdev->dev);
+ if (ipi)
+ zynqmp_r5_rproc_ops.kick = zynqmp_r5_rproc_kick;
+ else
+ zynqmp_r5_rproc_ops.kick = NULL;
+
Based on the way this patchset has turned out, I don't think it is required to
do this anymore. After all, .kick() won't be called if the mailboxes aren't
initialized.
Please move the call to zynqmp_r5_setup_mbox() just below in the next hunk.
I don't understand this.
So, we are still registering kick call back even if mailboxes aren't setup ?
I am okay with that, I will check flow once more.
Thanks,
Mathieu
/* create and add remoteproc instance of type struct rproc */
r5_cores[i] = zynqmp_r5_add_rproc_core(&child_pdev->dev);
if (IS_ERR(r5_cores[i])) {
@@ -878,6 +1094,11 @@ static int zynqmp_r5_cluster_init(struct zynqmp_r5_cluster *cluster)
goto release_r5_cores;
}
+ if (ipi) {
+ r5_cores[i]->ipi = ipi;
+ ipi->r5_core = r5_cores[i];
+ }
+
/*
* If two child nodes are available in dts in lockstep mode,
* then ignore second child node.
@@ -915,6 +1136,7 @@ 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);
of_reserved_mem_device_release(r5_cores[i]->dev);
rproc_del(r5_cores[i]->rproc);
rproc_free(r5_cores[i]->rproc);
@@ -939,6 +1161,7 @@ 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