diff options
| -rw-r--r-- | Documentation/devicetree/bindings/firmware/arm,scmi.yaml | 48 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/bus.c | 3 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 16 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/mailbox.c | 120 |
4 files changed, 162 insertions, 25 deletions
diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml index 2f7c51c75e85..5824c43e9893 100644 --- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml +++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml @@ -56,17 +56,38 @@ properties: description: Specifies the mailboxes used to communicate with SCMI compliant firmware. - items: - - const: tx - - const: rx + oneOf: + - items: + - const: tx + - const: rx + minItems: 1 + - items: + - const: tx + - const: tx_reply + - const: rx + minItems: 2 mboxes: description: List of phandle and mailbox channel specifiers. It should contain - exactly one or two mailboxes, one for transmitting messages("tx") - and another optional for receiving the notifications("rx") if supported. + exactly one, two or three mailboxes; the first one or two for transmitting + messages ("tx") and another optional ("rx") for receiving notifications + and delayed responses, if supported by the platform. + The number of mailboxes needed for transmitting messages depends on the + type of channels exposed by the specific underlying mailbox controller; + one single channel descriptor is enough if such channel is bidirectional, + while two channel descriptors are needed to represent the SCMI ("tx") + channel if the underlying mailbox channels are of unidirectional type. + The effective combination in numbers of mboxes and shmem descriptors let + the SCMI subsystem determine unambiguosly which type of SCMI channels are + made available by the underlying mailbox controller and how to use them. + 1 mbox / 1 shmem => SCMI TX over 1 mailbox bidirectional channel + 2 mbox / 2 shmem => SCMI TX and RX over 2 mailbox bidirectional channels + 2 mbox / 1 shmem => SCMI TX over 2 mailbox unidirectional channels + 3 mbox / 2 shmem => SCMI TX and RX over 3 mailbox unidirectional channels + Any other combination of mboxes and shmem is invalid. minItems: 1 - maxItems: 2 + maxItems: 3 shmem: description: @@ -228,13 +249,20 @@ $defs: maxItems: 1 mbox-names: - items: - - const: tx - - const: rx + oneOf: + - items: + - const: tx + - const: rx + minItems: 1 + - items: + - const: tx + - const: tx_reply + - const: rx + minItems: 2 mboxes: minItems: 1 - maxItems: 2 + maxItems: 3 shmem: minItems: 1 diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c index 73140b854b31..c15928b8c5cc 100644 --- a/drivers/firmware/arm_scmi/bus.c +++ b/drivers/firmware/arm_scmi/bus.c @@ -14,7 +14,6 @@ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/device.h> -#include <linux/of.h> #include "common.h" @@ -436,7 +435,7 @@ struct scmi_device *scmi_device_create(struct device_node *np, /* Nothing to do. */ if (!phead) { mutex_unlock(&scmi_requested_devices_mtx); - return scmi_dev; + return NULL; } /* Walk the list of requested devices for protocol and create them */ diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index d21c7eafd641..e7d97b59963b 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -2221,8 +2221,8 @@ static int __scmi_xfer_info_init(struct scmi_info *sinfo, hash_init(info->pending_xfers); /* Allocate a bitmask sized to hold MSG_TOKEN_MAX tokens */ - info->xfer_alloc_table = devm_kcalloc(dev, BITS_TO_LONGS(MSG_TOKEN_MAX), - sizeof(long), GFP_KERNEL); + info->xfer_alloc_table = devm_bitmap_zalloc(dev, MSG_TOKEN_MAX, + GFP_KERNEL); if (!info->xfer_alloc_table) return -ENOMEM; @@ -2289,7 +2289,7 @@ static int scmi_xfer_info_init(struct scmi_info *sinfo) return ret; ret = __scmi_xfer_info_init(sinfo, &sinfo->tx_minfo); - if (!ret && idr_find(&sinfo->rx_idr, SCMI_PROTOCOL_BASE)) + if (!ret && !idr_is_empty(&sinfo->rx_idr)) ret = __scmi_xfer_info_init(sinfo, &sinfo->rx_minfo); return ret; @@ -2657,6 +2657,7 @@ static int scmi_probe(struct platform_device *pdev) struct scmi_handle *handle; const struct scmi_desc *desc; struct scmi_info *info; + bool coex = IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT_COEX); struct device *dev = &pdev->dev; struct device_node *child, *np = dev->of_node; @@ -2731,16 +2732,13 @@ static int scmi_probe(struct platform_device *pdev) dev_warn(dev, "Failed to setup SCMI debugfs.\n"); if (IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT)) { - bool coex = - IS_ENABLED(CONFIG_ARM_SCMI_RAW_MODE_SUPPORT_COEX); - ret = scmi_debugfs_raw_mode_setup(info); if (!coex) { if (ret) goto clear_dev_req_notifier; - /* Bail out anyway when coex enabled */ - return ret; + /* Bail out anyway when coex disabled. */ + return 0; } /* Coex enabled, carry on in any case. */ @@ -2764,6 +2762,8 @@ static int scmi_probe(struct platform_device *pdev) ret = scmi_protocol_acquire(handle, SCMI_PROTOCOL_BASE); if (ret) { dev_err(dev, "unable to communicate with SCMI\n"); + if (coex) + return 0; goto notification_exit; } diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c index 0d9c9538b7f4..1efa5e9392c4 100644 --- a/drivers/firmware/arm_scmi/mailbox.c +++ b/drivers/firmware/arm_scmi/mailbox.c @@ -19,13 +19,15 @@ * struct scmi_mailbox - Structure representing a SCMI mailbox transport * * @cl: Mailbox Client - * @chan: Transmit/Receive mailbox channel + * @chan: Transmit/Receive mailbox uni/bi-directional channel + * @chan_receiver: Optional Receiver mailbox unidirectional channel * @cinfo: SCMI channel info * @shmem: Transmit/Receive shared memory area */ struct scmi_mailbox { struct mbox_client cl; struct mbox_chan *chan; + struct mbox_chan *chan_receiver; struct scmi_chan_info *cinfo; struct scmi_shared_mem __iomem *shmem; }; @@ -48,10 +50,98 @@ static void rx_callback(struct mbox_client *cl, void *m) static bool mailbox_chan_available(struct device_node *of_node, int idx) { + int num_mb; + + /* + * Just check if bidirrectional channels are involved, and check the + * index accordingly; proper full validation will be made later + * in mailbox_chan_setup(). + */ + num_mb = of_count_phandle_with_args(of_node, "mboxes", "#mbox-cells"); + if (num_mb == 3 && idx == 1) + idx = 2; + return !of_parse_phandle_with_args(of_node, "mboxes", "#mbox-cells", idx, NULL); } +/** + * mailbox_chan_validate - Validate transport configuration and map channels + * + * @cdev: Reference to the underlying transport device carrying the + * of_node descriptor to analyze. + * @a2p_rx_chan: A reference to an optional unidirectional channel to use + * for replies on the a2p channel. Set as zero if not present. + * @p2a_chan: A reference to the optional p2a channel. + * Set as zero if not present. + * + * At first, validate the transport configuration as described in terms of + * 'mboxes' and 'shmem', then determin which mailbox channel indexes are + * appropriate to be use in the current configuration. + * + * Return: 0 on Success or error + */ +static int mailbox_chan_validate(struct device *cdev, + int *a2p_rx_chan, int *p2a_chan) +{ + int num_mb, num_sh, ret = 0; + struct device_node *np = cdev->of_node; + + num_mb = of_count_phandle_with_args(np, "mboxes", "#mbox-cells"); + num_sh = of_count_phandle_with_args(np, "shmem", NULL); + dev_dbg(cdev, "Found %d mboxes and %d shmems !\n", num_mb, num_sh); + + /* Bail out if mboxes and shmem descriptors are inconsistent */ + if (num_mb <= 0 || num_sh <= 0 || num_sh > 2 || num_mb > 3 || + (num_mb == 1 && num_sh != 1) || (num_mb == 3 && num_sh != 2)) { + dev_warn(cdev, + "Invalid channel descriptor for '%s' - mbs:%d shm:%d\n", + of_node_full_name(np), num_mb, num_sh); + return -EINVAL; + } + + /* Bail out if provided shmem descriptors do not refer distinct areas */ + if (num_sh > 1) { + struct device_node *np_tx, *np_rx; + + np_tx = of_parse_phandle(np, "shmem", 0); + np_rx = of_parse_phandle(np, "shmem", 1); + if (!np_tx || !np_rx || np_tx == np_rx) { + dev_warn(cdev, "Invalid shmem descriptor for '%s'\n", + of_node_full_name(np)); + ret = -EINVAL; + } + + of_node_put(np_tx); + of_node_put(np_rx); + } + + /* Calculate channels IDs to use depending on mboxes/shmem layout */ + if (!ret) { + switch (num_mb) { + case 1: + *a2p_rx_chan = 0; + *p2a_chan = 0; + break; + case 2: + if (num_sh == 2) { + *a2p_rx_chan = 0; + *p2a_chan = 1; + } else { + *a2p_rx_chan = 1; + *p2a_chan = 0; + } + break; + case 3: + *a2p_rx_chan = 1; + *p2a_chan = 2; + break; + } + } + + return ret; +} + static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, bool tx) { @@ -59,11 +149,18 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, struct device *cdev = cinfo->dev; struct scmi_mailbox *smbox; struct device_node *shmem; - int ret, idx = tx ? 0 : 1; + int ret, a2p_rx_chan, p2a_chan, idx = tx ? 0 : 1; struct mbox_client *cl; resource_size_t size; struct resource res; + ret = mailbox_chan_validate(cdev, &a2p_rx_chan, &p2a_chan); + if (ret) + return ret; + + if (!tx && !p2a_chan) + return -ENODEV; + smbox = devm_kzalloc(dev, sizeof(*smbox), GFP_KERNEL); if (!smbox) return -ENOMEM; @@ -93,15 +190,26 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev, cl->tx_block = false; cl->knows_txdone = tx; - smbox->chan = mbox_request_channel(cl, tx ? 0 : 1); + smbox->chan = mbox_request_channel(cl, tx ? 0 : p2a_chan); if (IS_ERR(smbox->chan)) { ret = PTR_ERR(smbox->chan); if (ret != -EPROBE_DEFER) - dev_err(cdev, "failed to request SCMI %s mailbox\n", - tx ? "Tx" : "Rx"); + dev_err(cdev, + "failed to request SCMI %s mailbox\n", desc); return ret; } + /* Additional unidirectional channel for TX if needed */ + if (tx && a2p_rx_chan) { + smbox->chan_receiver = mbox_request_channel(cl, a2p_rx_chan); + if (IS_ERR(smbox->chan_receiver)) { + ret = PTR_ERR(smbox->chan_receiver); + if (ret != -EPROBE_DEFER) + dev_err(cdev, "failed to request SCMI Tx Receiver mailbox\n"); + return ret; + } + } + cinfo->transport_info = smbox; smbox->cinfo = cinfo; @@ -115,8 +223,10 @@ static int mailbox_chan_free(int id, void *p, void *data) if (smbox && !IS_ERR(smbox->chan)) { mbox_free_channel(smbox->chan); + mbox_free_channel(smbox->chan_receiver); cinfo->transport_info = NULL; smbox->chan = NULL; + smbox->chan_receiver = NULL; smbox->cinfo = NULL; } |