diff options
Diffstat (limited to 'drivers/firmware/imx/imx-scu.c')
| -rw-r--r-- | drivers/firmware/imx/imx-scu.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/drivers/firmware/imx/imx-scu.c b/drivers/firmware/imx/imx-scu.c new file mode 100644 index 000000000000..2bb1a19c413f --- /dev/null +++ b/drivers/firmware/imx/imx-scu.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2018 NXP + * Author: Dong Aisheng <aisheng.dong@nxp.com> + * + * Implementation of the SCU IPC functions using MUs (client side). + * + */ + +#include <linux/err.h> +#include <linux/firmware/imx/types.h> +#include <linux/firmware/imx/ipc.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/mailbox_client.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +#define SCU_MU_CHAN_NUM 8 +#define MAX_RX_TIMEOUT (msecs_to_jiffies(30)) + +struct imx_sc_chan { + struct imx_sc_ipc *sc_ipc; + + struct mbox_client cl; + struct mbox_chan *ch; + int idx; +}; + +struct imx_sc_ipc { + /* SCU uses 4 Tx and 4 Rx channels */ + struct imx_sc_chan chans[SCU_MU_CHAN_NUM]; + struct device *dev; + struct mutex lock; + struct completion done; + + /* temporarily store the SCU msg */ + u32 *msg; + u8 rx_size; + u8 count; +}; + +/* + * This type is used to indicate error response for most functions. + */ +enum imx_sc_error_codes { + IMX_SC_ERR_NONE = 0, /* Success */ + IMX_SC_ERR_VERSION = 1, /* Incompatible API version */ + IMX_SC_ERR_CONFIG = 2, /* Configuration error */ + IMX_SC_ERR_PARM = 3, /* Bad parameter */ + IMX_SC_ERR_NOACCESS = 4, /* Permission error (no access) */ + IMX_SC_ERR_LOCKED = 5, /* Permission error (locked) */ + IMX_SC_ERR_UNAVAILABLE = 6, /* Unavailable (out of resources) */ + IMX_SC_ERR_NOTFOUND = 7, /* Not found */ + IMX_SC_ERR_NOPOWER = 8, /* No power */ + IMX_SC_ERR_IPC = 9, /* Generic IPC error */ + IMX_SC_ERR_BUSY = 10, /* Resource is currently busy/active */ + IMX_SC_ERR_FAIL = 11, /* General I/O failure */ + IMX_SC_ERR_LAST +}; + +static int imx_sc_linux_errmap[IMX_SC_ERR_LAST] = { + 0, /* IMX_SC_ERR_NONE */ + -EINVAL, /* IMX_SC_ERR_VERSION */ + -EINVAL, /* IMX_SC_ERR_CONFIG */ + -EINVAL, /* IMX_SC_ERR_PARM */ + -EACCES, /* IMX_SC_ERR_NOACCESS */ + -EACCES, /* IMX_SC_ERR_LOCKED */ + -ERANGE, /* IMX_SC_ERR_UNAVAILABLE */ + -EEXIST, /* IMX_SC_ERR_NOTFOUND */ + -EPERM, /* IMX_SC_ERR_NOPOWER */ + -EPIPE, /* IMX_SC_ERR_IPC */ + -EBUSY, /* IMX_SC_ERR_BUSY */ + -EIO, /* IMX_SC_ERR_FAIL */ +}; + +static struct imx_sc_ipc *imx_sc_ipc_handle; + +static inline int imx_sc_to_linux_errno(int errno) +{ + if (errno >= IMX_SC_ERR_NONE && errno < IMX_SC_ERR_LAST) + return imx_sc_linux_errmap[errno]; + return -EIO; +} + +/* + * Get the default handle used by SCU + */ +int imx_scu_get_handle(struct imx_sc_ipc **ipc) +{ + if (!imx_sc_ipc_handle) + return -EPROBE_DEFER; + + *ipc = imx_sc_ipc_handle; + return 0; +} +EXPORT_SYMBOL(imx_scu_get_handle); + +static void imx_scu_rx_callback(struct mbox_client *c, void *msg) +{ + struct imx_sc_chan *sc_chan = container_of(c, struct imx_sc_chan, cl); + struct imx_sc_ipc *sc_ipc = sc_chan->sc_ipc; + struct imx_sc_rpc_msg *hdr; + u32 *data = msg; + + if (sc_chan->idx == 0) { + hdr = msg; + sc_ipc->rx_size = hdr->size; + dev_dbg(sc_ipc->dev, "msg rx size %u\n", sc_ipc->rx_size); + if (sc_ipc->rx_size > 4) + dev_warn(sc_ipc->dev, "RPC does not support receiving over 4 words: %u\n", + sc_ipc->rx_size); + } + + sc_ipc->msg[sc_chan->idx] = *data; + sc_ipc->count++; + + dev_dbg(sc_ipc->dev, "mu %u msg %u 0x%x\n", sc_chan->idx, + sc_ipc->count, *data); + + if ((sc_ipc->rx_size != 0) && (sc_ipc->count == sc_ipc->rx_size)) + complete(&sc_ipc->done); +} + +static int imx_scu_ipc_write(struct imx_sc_ipc *sc_ipc, void *msg) +{ + struct imx_sc_rpc_msg *hdr = msg; + struct imx_sc_chan *sc_chan; + u32 *data = msg; + int ret; + int i; + + /* Check size */ + if (hdr->size > IMX_SC_RPC_MAX_MSG) + return -EINVAL; + + 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++) { + sc_chan = &sc_ipc->chans[i % 4]; + ret = mbox_send_message(sc_chan->ch, &data[i]); + if (ret < 0) + return ret; + } + + return 0; +} + +/* + * RPC command/response + */ +int imx_scu_call_rpc(struct imx_sc_ipc *sc_ipc, void *msg, bool have_resp) +{ + struct imx_sc_rpc_msg *hdr; + int ret; + + if (WARN_ON(!sc_ipc || !msg)) + return -EINVAL; + + mutex_lock(&sc_ipc->lock); + reinit_completion(&sc_ipc->done); + + sc_ipc->msg = msg; + sc_ipc->count = 0; + ret = imx_scu_ipc_write(sc_ipc, msg); + if (ret < 0) { + dev_err(sc_ipc->dev, "RPC send msg failed: %d\n", ret); + goto out; + } + + if (have_resp) { + if (!wait_for_completion_timeout(&sc_ipc->done, + MAX_RX_TIMEOUT)) { + dev_err(sc_ipc->dev, "RPC send msg timeout\n"); + mutex_unlock(&sc_ipc->lock); + return -ETIMEDOUT; + } + + /* response status is stored in hdr->func field */ + hdr = msg; + ret = hdr->func; + } + +out: + mutex_unlock(&sc_ipc->lock); + + dev_dbg(sc_ipc->dev, "RPC SVC done\n"); + + return imx_sc_to_linux_errno(ret); +} +EXPORT_SYMBOL(imx_scu_call_rpc); + +static int imx_scu_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct imx_sc_ipc *sc_ipc; + struct imx_sc_chan *sc_chan; + struct mbox_client *cl; + char *chan_name; + int ret; + int i; + + sc_ipc = devm_kzalloc(dev, sizeof(*sc_ipc), GFP_KERNEL); + if (!sc_ipc) + return -ENOMEM; + + for (i = 0; i < SCU_MU_CHAN_NUM; i++) { + if (i < 4) + chan_name = kasprintf(GFP_KERNEL, "tx%d", i); + else + chan_name = kasprintf(GFP_KERNEL, "rx%d", i - 4); + + if (!chan_name) + return -ENOMEM; + + sc_chan = &sc_ipc->chans[i]; + cl = &sc_chan->cl; + cl->dev = dev; + cl->tx_block = false; + cl->knows_txdone = true; + cl->rx_callback = imx_scu_rx_callback; + + sc_chan->sc_ipc = sc_ipc; + sc_chan->idx = i % 4; + sc_chan->ch = mbox_request_channel_byname(cl, chan_name); + if (IS_ERR(sc_chan->ch)) { + ret = PTR_ERR(sc_chan->ch); + if (ret != -EPROBE_DEFER) + dev_err(dev, "Failed to request mbox chan %s ret %d\n", + chan_name, ret); + return ret; + } + + dev_dbg(dev, "request mbox chan %s\n", chan_name); + /* chan_name is not used anymore by framework */ + kfree(chan_name); + } + + sc_ipc->dev = dev; + mutex_init(&sc_ipc->lock); + init_completion(&sc_ipc->done); + + imx_sc_ipc_handle = sc_ipc; + + dev_info(dev, "NXP i.MX SCU Initialized\n"); + + return devm_of_platform_populate(dev); +} + +static const struct of_device_id imx_scu_match[] = { + { .compatible = "fsl,imx-scu", }, + { /* Sentinel */ } +}; + +static struct platform_driver imx_scu_driver = { + .driver = { + .name = "imx-scu", + .of_match_table = imx_scu_match, + }, + .probe = imx_scu_probe, +}; +builtin_platform_driver(imx_scu_driver); + +MODULE_AUTHOR("Dong Aisheng <aisheng.dong@nxp.com>"); +MODULE_DESCRIPTION("IMX SCU firmware protocol driver"); +MODULE_LICENSE("GPL v2"); |