firmware: imx-scu: Support one TX and one RX

[ Upstream commit f25a066d1a07affb7bea4e5d9c179c3338338e23 ]

Current imx-scu requires four TX and four RX to communicate with
SCU. This is low efficient and causes lots of mailbox interrupts.

With imx-mailbox driver could support one TX to use all four transmit
registers and one RX to use all four receive registers, imx-scu
could use one TX and one RX.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/firmware/imx/imx-scu.c b/drivers/firmware/imx/imx-scu.c
index 6c6ac47..a92adb9 100644 (file)
--- a/drivers/firmware/imx/imx-scu.c
+++ b/drivers/firmware/imx/imx-scu.c
@@ -38,6 +38,7 @@ struct imx_sc_ipc {
        struct device *dev;
        struct mutex lock;
        struct completion done;
+       bool fast_ipc;
 
        /* temporarily store the SCU msg */
        u32 *msg;
@@ -115,6 +116,7 @@ static void imx_scu_rx_callback(struct mbox_client *c, void *msg)
        struct imx_sc_ipc *sc_ipc = sc_chan->sc_ipc;
        struct imx_sc_rpc_msg *hdr;
        u32 *data = msg;
+       int i;
 
        if (!sc_ipc->msg) {
                dev_warn(sc_ipc->dev, "unexpected rx idx %d 0x%08x, ignore!\n",
@@ -122,6 +124,19 @@ static void imx_scu_rx_callback(struct mbox_client *c, void *msg)
                return;
        }
 
+       if (sc_ipc->fast_ipc) {
+               hdr = msg;
+               sc_ipc->rx_size = hdr->size;
+               sc_ipc->msg[0] = *data++;
+
+               for (i = 1; i < sc_ipc->rx_size; i++)
+                       sc_ipc->msg[i] = *data++;
+
+               complete(&sc_ipc->done);
+
+               return;
+       }
+
        if (sc_chan->idx == 0) {
                hdr = msg;
                sc_ipc->rx_size = hdr->size;
@@ -147,6 +162,7 @@ static int imx_scu_ipc_write(struct imx_sc_ipc *sc_ipc, void *msg)
        struct imx_sc_chan *sc_chan;
        u32 *data = msg;
        int ret;
+       int size;
        int i;
 
        /* Check size */
@@ -156,7 +172,8 @@ static int imx_scu_ipc_write(struct imx_sc_ipc *sc_ipc, void *msg)
        dev_dbg(sc_ipc->dev, "RPC SVC %u FUNC %u SIZE %u\n", hdr->svc,
                hdr->func, hdr->size);
 
-       for (i = 0; i < hdr->size; i++) {
+       size = sc_ipc->fast_ipc ? 1 : hdr->size;
+       for (i = 0; i < size; i++) {
                sc_chan = &sc_ipc->chans[i % 4];
 
                /*
@@ -168,8 +185,10 @@ static int imx_scu_ipc_write(struct imx_sc_ipc *sc_ipc, void *msg)
                 * Wait for tx_done before every send to ensure that no
                 * queueing happens at the mailbox channel level.
                 */
-               wait_for_completion(&sc_chan->tx_done);
-               reinit_completion(&sc_chan->tx_done);
+               if (!sc_ipc->fast_ipc) {
+                       wait_for_completion(&sc_chan->tx_done);
+                       reinit_completion(&sc_chan->tx_done);
+               }
 
                ret = mbox_send_message(sc_chan->ch, &data[i]);
                if (ret < 0)
@@ -232,6 +251,8 @@ static int imx_scu_probe(struct platform_device *pdev)
        struct imx_sc_chan *sc_chan;
        struct mbox_client *cl;
        char *chan_name;
+       struct of_phandle_args args;
+       int num_channel;
        int ret;
        int i;
 
@@ -239,11 +260,20 @@ static int imx_scu_probe(struct platform_device *pdev)
        if (!sc_ipc)
                return -ENOMEM;
 
-       for (i = 0; i < SCU_MU_CHAN_NUM; i++) {
-               if (i < 4)
+       ret = of_parse_phandle_with_args(pdev->dev.of_node, "mboxes",
+                                        "#mbox-cells", 0, &args);
+       if (ret)
+               return ret;
+
+       sc_ipc->fast_ipc = of_device_is_compatible(args.np, "fsl,imx8-mu-scu");
+
+       num_channel = sc_ipc->fast_ipc ? 2 : SCU_MU_CHAN_NUM;
+       for (i = 0; i < num_channel; i++) {
+               if (i < num_channel / 2)
                        chan_name = kasprintf(GFP_KERNEL, "tx%d", i);
                else
-                       chan_name = kasprintf(GFP_KERNEL, "rx%d", i - 4);
+                       chan_name = kasprintf(GFP_KERNEL, "rx%d",
+                                             i - num_channel / 2);
 
                if (!chan_name)
                        return -ENOMEM;
@@ -255,13 +285,15 @@ static int imx_scu_probe(struct platform_device *pdev)
                cl->knows_txdone = true;
                cl->rx_callback = imx_scu_rx_callback;
 
-               /* Initial tx_done completion as "done" */
-               cl->tx_done = imx_scu_tx_done;
-               init_completion(&sc_chan->tx_done);
-               complete(&sc_chan->tx_done);
+               if (!sc_ipc->fast_ipc) {
+                       /* Initial tx_done completion as "done" */
+                       cl->tx_done = imx_scu_tx_done;
+                       init_completion(&sc_chan->tx_done);
+                       complete(&sc_chan->tx_done);
+               }
 
                sc_chan->sc_ipc = sc_ipc;
-               sc_chan->idx = i % 4;
+               sc_chan->idx = i % (num_channel / 2);
                sc_chan->ch = mbox_request_channel_byname(cl, chan_name);
                if (IS_ERR(sc_chan->ch)) {
                        ret = PTR_ERR(sc_chan->ch);