diff options
Diffstat (limited to 'drivers/mailbox')
| -rw-r--r-- | drivers/mailbox/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/mailbox/Makefile | 2 | ||||
| -rw-r--r-- | drivers/mailbox/mailbox.c | 65 | ||||
| -rw-r--r-- | drivers/mailbox/riscv-sbi-mpxy-mbox.c | 1019 |
4 files changed, 1072 insertions, 25 deletions
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index 02432d4a5ccd..c488725aa2a5 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -369,4 +369,15 @@ config BCM74110_MAILBOX processor and coprocessor that handles various power management task and more. +config RISCV_SBI_MPXY_MBOX + tristate "RISC-V SBI Message Proxy (MPXY) Mailbox" + depends on RISCV_SBI + default RISCV + help + Mailbox driver implementation for RISC-V SBI Message Proxy (MPXY) + extension. This mailbox driver is used to send messages to the + remote processor through the SBI implementation (M-mode firmware + or HS-mode hypervisor). Say Y here if you want to have this support. + If unsure say N. + endif diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index 98a68f838486..f9a11f5639aa 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -78,3 +78,5 @@ obj-$(CONFIG_THEAD_TH1520_MBOX) += mailbox-th1520.o obj-$(CONFIG_CIX_MBOX) += cix-mailbox.o obj-$(CONFIG_BCM74110_MAILBOX) += bcm74110-mailbox.o + +obj-$(CONFIG_RISCV_SBI_MPXY_MBOX) += riscv-sbi-mpxy-mbox.o diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c index 5cd8ae222073..2acc6ec229a4 100644 --- a/drivers/mailbox/mailbox.c +++ b/drivers/mailbox/mailbox.c @@ -15,6 +15,7 @@ #include <linux/module.h> #include <linux/mutex.h> #include <linux/of.h> +#include <linux/property.h> #include <linux/spinlock.h> #include "mailbox.h" @@ -383,34 +384,56 @@ EXPORT_SYMBOL_GPL(mbox_bind_client); */ struct mbox_chan *mbox_request_channel(struct mbox_client *cl, int index) { - struct device *dev = cl->dev; + struct fwnode_reference_args fwspec; + struct fwnode_handle *fwnode; struct mbox_controller *mbox; struct of_phandle_args spec; struct mbox_chan *chan; + struct device *dev; + unsigned int i; int ret; - if (!dev || !dev->of_node) { - pr_debug("%s: No owner device node\n", __func__); + dev = cl->dev; + if (!dev) { + pr_debug("No owner device\n"); return ERR_PTR(-ENODEV); } - ret = of_parse_phandle_with_args(dev->of_node, "mboxes", "#mbox-cells", - index, &spec); + fwnode = dev_fwnode(dev); + if (!fwnode) { + dev_dbg(dev, "No owner fwnode\n"); + return ERR_PTR(-ENODEV); + } + + ret = fwnode_property_get_reference_args(fwnode, "mboxes", "#mbox-cells", + 0, index, &fwspec); if (ret) { - dev_err(dev, "%s: can't parse \"mboxes\" property\n", __func__); + dev_err(dev, "%s: can't parse \"%s\" property\n", __func__, "mboxes"); return ERR_PTR(ret); } + spec.np = to_of_node(fwspec.fwnode); + spec.args_count = fwspec.nargs; + for (i = 0; i < spec.args_count; i++) + spec.args[i] = fwspec.args[i]; + scoped_guard(mutex, &con_mutex) { chan = ERR_PTR(-EPROBE_DEFER); - list_for_each_entry(mbox, &mbox_cons, node) - if (mbox->dev->of_node == spec.np) { - chan = mbox->of_xlate(mbox, &spec); - if (!IS_ERR(chan)) - break; + list_for_each_entry(mbox, &mbox_cons, node) { + if (device_match_fwnode(mbox->dev, fwspec.fwnode)) { + if (mbox->fw_xlate) { + chan = mbox->fw_xlate(mbox, &fwspec); + if (!IS_ERR(chan)) + break; + } else if (mbox->of_xlate) { + chan = mbox->of_xlate(mbox, &spec); + if (!IS_ERR(chan)) + break; + } } + } - of_node_put(spec.np); + fwnode_handle_put(fwspec.fwnode); if (IS_ERR(chan)) return chan; @@ -427,15 +450,8 @@ EXPORT_SYMBOL_GPL(mbox_request_channel); struct mbox_chan *mbox_request_channel_byname(struct mbox_client *cl, const char *name) { - struct device_node *np = cl->dev->of_node; - int index; - - if (!np) { - dev_err(cl->dev, "%s() currently only supports DT\n", __func__); - return ERR_PTR(-EINVAL); - } + int index = device_property_match_string(cl->dev, "mbox-names", name); - index = of_property_match_string(np, "mbox-names", name); if (index < 0) { dev_err(cl->dev, "%s() could not locate channel named \"%s\"\n", __func__, name); @@ -470,9 +486,8 @@ void mbox_free_channel(struct mbox_chan *chan) } EXPORT_SYMBOL_GPL(mbox_free_channel); -static struct mbox_chan * -of_mbox_index_xlate(struct mbox_controller *mbox, - const struct of_phandle_args *sp) +static struct mbox_chan *fw_mbox_index_xlate(struct mbox_controller *mbox, + const struct fwnode_reference_args *sp) { int ind = sp->args[0]; @@ -523,8 +538,8 @@ int mbox_controller_register(struct mbox_controller *mbox) spin_lock_init(&chan->lock); } - if (!mbox->of_xlate) - mbox->of_xlate = of_mbox_index_xlate; + if (!mbox->fw_xlate && !mbox->of_xlate) + mbox->fw_xlate = fw_mbox_index_xlate; scoped_guard(mutex, &con_mutex) list_add_tail(&mbox->node, &mbox_cons); diff --git a/drivers/mailbox/riscv-sbi-mpxy-mbox.c b/drivers/mailbox/riscv-sbi-mpxy-mbox.c new file mode 100644 index 000000000000..7c9c006b7244 --- /dev/null +++ b/drivers/mailbox/riscv-sbi-mpxy-mbox.c @@ -0,0 +1,1019 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RISC-V SBI Message Proxy (MPXY) mailbox controller driver + * + * Copyright (C) 2025 Ventana Micro Systems Inc. + */ + +#include <linux/acpi.h> +#include <linux/cpu.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/irqchip/riscv-imsic.h> +#include <linux/mailbox_controller.h> +#include <linux/mailbox/riscv-rpmi-message.h> +#include <linux/minmax.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/msi.h> +#include <linux/of_irq.h> +#include <linux/percpu.h> +#include <linux/platform_device.h> +#include <linux/smp.h> +#include <linux/string.h> +#include <linux/types.h> +#include <asm/byteorder.h> +#include <asm/sbi.h> + +/* ====== SBI MPXY extension data structures ====== */ + +/* SBI MPXY MSI related channel attributes */ +struct sbi_mpxy_msi_info { + /* Lower 32-bits of the MSI target address */ + u32 msi_addr_lo; + /* Upper 32-bits of the MSI target address */ + u32 msi_addr_hi; + /* MSI data value */ + u32 msi_data; +}; + +/* + * SBI MPXY standard channel attributes. + * + * NOTE: The sequence of attribute fields are as-per the + * defined sequence in the attribute table in spec (or + * as-per the enum sbi_mpxy_attribute_id). + */ +struct sbi_mpxy_channel_attrs { + /* Message protocol ID */ + u32 msg_proto_id; + /* Message protocol version */ + u32 msg_proto_version; + /* Message protocol maximum message length */ + u32 msg_max_len; + /* Message protocol message send timeout in microseconds */ + u32 msg_send_timeout; + /* Message protocol message completion timeout in microseconds */ + u32 msg_completion_timeout; + /* Bit array for channel capabilities */ + u32 capability; + /* SSE event ID */ + u32 sse_event_id; + /* MSI enable/disable control knob */ + u32 msi_control; + /* Channel MSI info */ + struct sbi_mpxy_msi_info msi_info; + /* Events state control */ + u32 events_state_ctrl; +}; + +/* + * RPMI specific SBI MPXY channel attributes. + * + * NOTE: The sequence of attribute fields are as-per the + * defined sequence in the attribute table in spec (or + * as-per the enum sbi_mpxy_rpmi_attribute_id). + */ +struct sbi_mpxy_rpmi_channel_attrs { + /* RPMI service group ID */ + u32 servicegroup_id; + /* RPMI service group version */ + u32 servicegroup_version; + /* RPMI implementation ID */ + u32 impl_id; + /* RPMI implementation version */ + u32 impl_version; +}; + +/* SBI MPXY channel IDs data in shared memory */ +struct sbi_mpxy_channel_ids_data { + /* Remaining number of channel ids */ + __le32 remaining; + /* Returned channel ids in current function call */ + __le32 returned; + /* Returned channel id array */ + __le32 channel_array[]; +}; + +/* SBI MPXY notification data in shared memory */ +struct sbi_mpxy_notification_data { + /* Remaining number of notification events */ + __le32 remaining; + /* Number of notification events returned */ + __le32 returned; + /* Number of notification events lost */ + __le32 lost; + /* Reserved for future use */ + __le32 reserved; + /* Returned channel id array */ + u8 events_data[]; +}; + +/* ====== MPXY data structures & helper routines ====== */ + +/* MPXY Per-CPU or local context */ +struct mpxy_local { + /* Shared memory base address */ + void *shmem; + /* Shared memory physical address */ + phys_addr_t shmem_phys_addr; + /* Flag representing whether shared memory is active or not */ + bool shmem_active; +}; + +static DEFINE_PER_CPU(struct mpxy_local, mpxy_local); +static unsigned long mpxy_shmem_size; +static bool mpxy_shmem_init_done; + +static int mpxy_get_channel_count(u32 *channel_count) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbi_mpxy_channel_ids_data *sdata = mpxy->shmem; + u32 remaining, returned; + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!channel_count) + return -EINVAL; + + get_cpu(); + + /* Get the remaining and returned fields to calculate total */ + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_CHANNEL_IDS, + 0, 0, 0, 0, 0, 0); + if (sret.error) + goto err_put_cpu; + + remaining = le32_to_cpu(sdata->remaining); + returned = le32_to_cpu(sdata->returned); + *channel_count = remaining + returned; + +err_put_cpu: + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_get_channel_ids(u32 channel_count, u32 *channel_ids) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbi_mpxy_channel_ids_data *sdata = mpxy->shmem; + u32 remaining, returned, count, start_index = 0; + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!channel_count || !channel_ids) + return -EINVAL; + + get_cpu(); + + do { + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_CHANNEL_IDS, + start_index, 0, 0, 0, 0, 0); + if (sret.error) + goto err_put_cpu; + + remaining = le32_to_cpu(sdata->remaining); + returned = le32_to_cpu(sdata->returned); + + count = returned < (channel_count - start_index) ? + returned : (channel_count - start_index); + memcpy_from_le32(&channel_ids[start_index], sdata->channel_array, count); + start_index += count; + } while (remaining && start_index < channel_count); + +err_put_cpu: + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_read_attrs(u32 channel_id, u32 base_attrid, u32 attr_count, + u32 *attrs_buf) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!attr_count || !attrs_buf) + return -EINVAL; + + get_cpu(); + + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_READ_ATTRS, + channel_id, base_attrid, attr_count, 0, 0, 0); + if (sret.error) + goto err_put_cpu; + + memcpy_from_le32(attrs_buf, (__le32 *)mpxy->shmem, attr_count); + +err_put_cpu: + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_write_attrs(u32 channel_id, u32 base_attrid, u32 attr_count, + u32 *attrs_buf) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!attr_count || !attrs_buf) + return -EINVAL; + + get_cpu(); + + memcpy_to_le32((__le32 *)mpxy->shmem, attrs_buf, attr_count); + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_WRITE_ATTRS, + channel_id, base_attrid, attr_count, 0, 0, 0); + + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_send_message_with_resp(u32 channel_id, u32 msg_id, + void *tx, unsigned long tx_len, + void *rx, unsigned long max_rx_len, + unsigned long *rx_len) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + unsigned long rx_bytes; + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!tx && tx_len) + return -EINVAL; + + get_cpu(); + + /* Message protocols allowed to have no data in messages */ + if (tx_len) + memcpy(mpxy->shmem, tx, tx_len); + + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SEND_MSG_WITH_RESP, + channel_id, msg_id, tx_len, 0, 0, 0); + if (rx && !sret.error) { + rx_bytes = sret.value; + if (rx_bytes > max_rx_len) { + put_cpu(); + return -ENOSPC; + } + + memcpy(rx, mpxy->shmem, rx_bytes); + if (rx_len) + *rx_len = rx_bytes; + } + + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_send_message_without_resp(u32 channel_id, u32 msg_id, + void *tx, unsigned long tx_len) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!tx && tx_len) + return -EINVAL; + + get_cpu(); + + /* Message protocols allowed to have no data in messages */ + if (tx_len) + memcpy(mpxy->shmem, tx, tx_len); + + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SEND_MSG_WITHOUT_RESP, + channel_id, msg_id, tx_len, 0, 0, 0); + + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_get_notifications(u32 channel_id, + struct sbi_mpxy_notification_data *notif_data, + unsigned long *events_data_len) +{ + struct mpxy_local *mpxy = this_cpu_ptr(&mpxy_local); + struct sbiret sret; + + if (!mpxy->shmem_active) + return -ENODEV; + if (!notif_data || !events_data_len) + return -EINVAL; + + get_cpu(); + + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_NOTIFICATION_EVENTS, + channel_id, 0, 0, 0, 0, 0); + if (sret.error) + goto err_put_cpu; + + memcpy(notif_data, mpxy->shmem, sret.value + 16); + *events_data_len = sret.value; + +err_put_cpu: + put_cpu(); + return sbi_err_map_linux_errno(sret.error); +} + +static int mpxy_get_shmem_size(unsigned long *shmem_size) +{ + struct sbiret sret; + + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_GET_SHMEM_SIZE, + 0, 0, 0, 0, 0, 0); + if (sret.error) + return sbi_err_map_linux_errno(sret.error); + if (shmem_size) + *shmem_size = sret.value; + return 0; +} + +static int mpxy_setup_shmem(unsigned int cpu) +{ + struct page *shmem_page; + struct mpxy_local *mpxy; + struct sbiret sret; + + mpxy = per_cpu_ptr(&mpxy_local, cpu); + if (mpxy->shmem_active) + return 0; + + shmem_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, get_order(mpxy_shmem_size)); + if (!shmem_page) + return -ENOMEM; + + /* + * Linux setup of shmem is done in mpxy OVERWRITE mode. + * flags[1:0] = 00b + */ + sret = sbi_ecall(SBI_EXT_MPXY, SBI_EXT_MPXY_SET_SHMEM, + page_to_phys(shmem_page), 0, 0, 0, 0, 0); + if (sret.error) { + free_pages((unsigned long)page_to_virt(shmem_page), + get_order(mpxy_shmem_size)); + return sbi_err_map_linux_errno(sret.error); + } + + mpxy->shmem = page_to_virt(shmem_page); + mpxy->shmem_phys_addr = page_to_phys(shmem_page); + mpxy->shmem_active = true; + + return 0; +} + +/* ====== MPXY mailbox data structures ====== */ + +/* MPXY mailbox channel */ +struct mpxy_mbox_channel { + struct mpxy_mbox *mbox; + u32 channel_id; + struct sbi_mpxy_channel_attrs attrs; + struct sbi_mpxy_rpmi_channel_attrs rpmi_attrs; + struct sbi_mpxy_notification_data *notif; + u32 max_xfer_len; + bool have_events_state; + u32 msi_index; + u32 msi_irq; + bool started; +}; + +/* MPXY mailbox */ +struct mpxy_mbox { + struct device *dev; + u32 channel_count; + struct mpxy_mbox_channel *channels; + u32 msi_count; + struct mpxy_mbox_channel **msi_index_to_channel; + struct mbox_controller controller; +}; + +/* ====== MPXY RPMI processing ====== */ + +static void mpxy_mbox_send_rpmi_data(struct mpxy_mbox_channel *mchan, + struct rpmi_mbox_message *msg) +{ + msg->error = 0; + switch (msg->type) { + case RPMI_MBOX_MSG_TYPE_GET_ATTRIBUTE: + switch (msg->attr.id) { + case RPMI_MBOX_ATTR_SPEC_VERSION: + msg->attr.value = mchan->attrs.msg_proto_version; + break; + case RPMI_MBOX_ATTR_MAX_MSG_DATA_SIZE: + msg->attr.value = mchan->max_xfer_len; + break; + case RPMI_MBOX_ATTR_SERVICEGROUP_ID: + msg->attr.value = mchan->rpmi_attrs.servicegroup_id; + break; + case RPMI_MBOX_ATTR_SERVICEGROUP_VERSION: + msg->attr.value = mchan->rpmi_attrs.servicegroup_version; + break; + case RPMI_MBOX_ATTR_IMPL_ID: + msg->attr.value = mchan->rpmi_attrs.impl_id; + break; + case RPMI_MBOX_ATTR_IMPL_VERSION: + msg->attr.value = mchan->rpmi_attrs.impl_version; + break; + default: + msg->error = -EOPNOTSUPP; + break; + } + break; + case RPMI_MBOX_MSG_TYPE_SET_ATTRIBUTE: + /* None of the RPMI linux mailbox attributes are writeable */ + msg->error = -EOPNOTSUPP; + break; + case RPMI_MBOX_MSG_TYPE_SEND_WITH_RESPONSE: + if ((!msg->data.request && msg->data.request_len) || + (msg->data.request && msg->data.request_len > mchan->max_xfer_len) || + (!msg->data.response && msg->data.max_response_len)) { + msg->error = -EINVAL; + break; + } + if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_SEND_WITH_RESP)) { + msg->error = -EIO; + break; + } + msg->error = mpxy_send_message_with_resp(mchan->channel_id, + msg->data.service_id, + msg->data.request, + msg->data.request_len, + msg->data.response, + msg->data.max_response_len, + &msg->data.out_response_len); + break; + case RPMI_MBOX_MSG_TYPE_SEND_WITHOUT_RESPONSE: + if ((!msg->data.request && msg->data.request_len) || + (msg->data.request && msg->data.request_len > mchan->max_xfer_len)) { + msg->error = -EINVAL; + break; + } + if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_SEND_WITHOUT_RESP)) { + msg->error = -EIO; + break; + } + msg->error = mpxy_send_message_without_resp(mchan->channel_id, + msg->data.service_id, + msg->data.request, + msg->data.request_len); + break; + default: + msg->error = -EOPNOTSUPP; + break; + } +} + +static void mpxy_mbox_peek_rpmi_data(struct mbox_chan *chan, + struct mpxy_mbox_channel *mchan, + struct sbi_mpxy_notification_data *notif, + unsigned long events_data_len) +{ + struct rpmi_notification_event *event; + struct rpmi_mbox_message msg; + unsigned long pos = 0; + + while (pos < events_data_len && (events_data_len - pos) <= sizeof(*event)) { + event = (struct rpmi_notification_event *)(notif->events_data + pos); + + msg.type = RPMI_MBOX_MSG_TYPE_NOTIFICATION_EVENT; + msg.notif.event_datalen = le16_to_cpu(event->event_datalen); + msg.notif.event_id = event->event_id; + msg.notif.event_data = event->event_data; + msg.error = 0; + + mbox_chan_received_data(chan, &msg); + pos += sizeof(*event) + msg.notif.event_datalen; + } +} + +static int mpxy_mbox_read_rpmi_attrs(struct mpxy_mbox_channel *mchan) +{ + return mpxy_read_attrs(mchan->channel_id, + SBI_MPXY_ATTR_MSGPROTO_ATTR_START, + sizeof(mchan->rpmi_attrs) / sizeof(u32), + (u32 *)&mchan->rpmi_attrs); +} + +/* ====== MPXY mailbox callbacks ====== */ + +static int mpxy_mbox_send_data(struct mbox_chan *chan, void *data) +{ + struct mpxy_mbox_channel *mchan = chan->con_priv; + + if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID) { + mpxy_mbox_send_rpmi_data(mchan, data); + return 0; + } + + return -EOPNOTSUPP; +} + +static bool mpxy_mbox_peek_data(struct mbox_chan *chan) +{ + struct mpxy_mbox_channel *mchan = chan->con_priv; + struct sbi_mpxy_notification_data *notif = mchan->notif; + bool have_notifications = false; + unsigned long data_len; + int rc; + + if (!(mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS)) + return false; + + do { + rc = mpxy_get_notifications(mchan->channel_id, notif, &data_len); + if (rc || !data_len) + break; + + if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID) + mpxy_mbox_peek_rpmi_data(chan, mchan, notif, data_len); + + have_notifications = true; + } while (1); + + return have_notifications; +} + +static irqreturn_t mpxy_mbox_irq_thread(int irq, void *dev_id) +{ + mpxy_mbox_peek_data(dev_id); + return IRQ_HANDLED; +} + +static int mpxy_mbox_setup_msi(struct mbox_chan *chan, + struct mpxy_mbox_channel *mchan) +{ + struct device *dev = mchan->mbox->dev; + int rc; + + /* Do nothing if MSI not supported */ + if (mchan->msi_irq == U32_MAX) + return 0; + + /* Fail if MSI already enabled */ + if (mchan->attrs.msi_control) + return -EALREADY; + + /* Request channel MSI handler */ + rc = request_threaded_irq(mchan->msi_irq, NULL, mpxy_mbox_irq_thread, + 0, dev_name(dev), chan); + if (rc) { + dev_err(dev, "failed to request MPXY channel 0x%x IRQ\n", + mchan->channel_id); + return rc; + } + + /* Enable channel MSI control */ + mchan->attrs.msi_control = 1; + rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_CONTROL, + 1, &mchan->attrs.msi_control); + if (rc) { + dev_err(dev, "enable MSI control failed for MPXY channel 0x%x\n", + mchan->channel_id); + mchan->attrs.msi_control = 0; + free_irq(mchan->msi_irq, chan); + return rc; + } + + return 0; +} + +static void mpxy_mbox_cleanup_msi(struct mbox_chan *chan, + struct mpxy_mbox_channel *mchan) +{ + struct device *dev = mchan->mbox->dev; + int rc; + + /* Do nothing if MSI not supported */ + if (mchan->msi_irq == U32_MAX) + return; + + /* Do nothing if MSI already disabled */ + if (!mchan->attrs.msi_control) + return; + + /* Disable channel MSI control */ + mchan->attrs.msi_control = 0; + rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_CONTROL, + 1, &mchan->attrs.msi_control); + if (rc) { + dev_err(dev, "disable MSI control failed for MPXY channel 0x%x\n", + mchan->channel_id); + } + + /* Free channel MSI handler */ + free_irq(mchan->msi_irq, chan); +} + +static int mpxy_mbox_setup_events(struct mpxy_mbox_channel *mchan) +{ + struct device *dev = mchan->mbox->dev; + int rc; + + /* Do nothing if events state not supported */ + if (!mchan->have_events_state) + return 0; + + /* Fail if events state already enabled */ + if (mchan->attrs.events_state_ctrl) + return -EALREADY; + + /* Enable channel events state */ + mchan->attrs.events_state_ctrl = 1; + rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_EVENTS_STATE_CONTROL, + 1, &mchan->attrs.events_state_ctrl); + if (rc) { + dev_err(dev, "enable events state failed for MPXY channel 0x%x\n", + mchan->channel_id); + mchan->attrs.events_state_ctrl = 0; + return rc; + } + + return 0; +} + +static void mpxy_mbox_cleanup_events(struct mpxy_mbox_channel *mchan) +{ + struct device *dev = mchan->mbox->dev; + int rc; + + /* Do nothing if events state not supported */ + if (!mchan->have_events_state) + return; + + /* Do nothing if events state already disabled */ + if (!mchan->attrs.events_state_ctrl) + return; + + /* Disable channel events state */ + mchan->attrs.events_state_ctrl = 0; + rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_EVENTS_STATE_CONTROL, + 1, &mchan->attrs.events_state_ctrl); + if (rc) + dev_err(dev, "disable events state failed for MPXY channel 0x%x\n", + mchan->channel_id); +} + +static int mpxy_mbox_startup(struct mbox_chan *chan) +{ + struct mpxy_mbox_channel *mchan = chan->con_priv; + int rc; + + if (mchan->started) + return -EALREADY; + + /* Setup channel MSI */ + rc = mpxy_mbox_setup_msi(chan, mchan); + if (rc) + return rc; + + /* Setup channel notification events */ + rc = mpxy_mbox_setup_events(mchan); + if (rc) { + mpxy_mbox_cleanup_msi(chan, mchan); + return rc; + } + + /* Mark the channel as started */ + mchan->started = true; + + return 0; +} + +static void mpxy_mbox_shutdown(struct mbox_chan *chan) +{ + struct mpxy_mbox_channel *mchan = chan->con_priv; + + if (!mchan->started) + return; + + /* Mark the channel as stopped */ + mchan->started = false; + + /* Cleanup channel notification events */ + mpxy_mbox_cleanup_events(mchan); + + /* Cleanup channel MSI */ + mpxy_mbox_cleanup_msi(chan, mchan); +} + +static const struct mbox_chan_ops mpxy_mbox_ops = { + .send_data = mpxy_mbox_send_data, + .peek_data = mpxy_mbox_peek_data, + .startup = mpxy_mbox_startup, + .shutdown = mpxy_mbox_shutdown, +}; + +/* ====== MPXY platform driver ===== */ + +static void mpxy_mbox_msi_write(struct msi_desc *desc, struct msi_msg *msg) +{ + struct device *dev = msi_desc_to_dev(desc); + struct mpxy_mbox *mbox = dev_get_drvdata(dev); + struct mpxy_mbox_channel *mchan; + struct sbi_mpxy_msi_info *minfo; + int rc; + + mchan = mbox->msi_index_to_channel[desc->msi_index]; + if (!mchan) { + dev_warn(dev, "MPXY channel not available for MSI index %d\n", + desc->msi_index); + return; + } + + minfo = &mchan->attrs.msi_info; + minfo->msi_addr_lo = msg->address_lo; + minfo->msi_addr_hi = msg->address_hi; + minfo->msi_data = msg->data; + + rc = mpxy_write_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSI_ADDR_LO, + sizeof(*minfo) / sizeof(u32), (u32 *)minfo); + if (rc) { + dev_warn(dev, "failed to write MSI info for MPXY channel 0x%x\n", + mchan->channel_id); + } +} + +static struct mbox_chan *mpxy_mbox_fw_xlate(struct mbox_controller *ctlr, + const struct fwnode_reference_args *pa) +{ + struct mpxy_mbox *mbox = container_of(ctlr, struct mpxy_mbox, controller); + struct mpxy_mbox_channel *mchan; + u32 i; + + if (pa->nargs != 2) + return ERR_PTR(-EINVAL); + + for (i = 0; i < mbox->channel_count; i++) { + mchan = &mbox->channels[i]; + if (mchan->channel_id == pa->args[0] && + mchan->attrs.msg_proto_id == pa->args[1]) + return &mbox->controller.chans[i]; + } + + return ERR_PTR(-ENOENT); +} + +static int mpxy_mbox_populate_channels(struct mpxy_mbox *mbox) +{ + u32 i, *channel_ids __free(kfree) = NULL; + struct mpxy_mbox_channel *mchan; + int rc; + + /* Find-out of number of channels */ + rc = mpxy_get_channel_count(&mbox->channel_count); + if (rc) + return dev_err_probe(mbox->dev, rc, "failed to get number of MPXY channels\n"); + if (!mbox->channel_count) + return dev_err_probe(mbox->dev, -ENODEV, "no MPXY channels available\n"); + + /* Allocate and fetch all channel IDs */ + channel_ids = kcalloc(mbox->channel_count, sizeof(*channel_ids), GFP_KERNEL); + if (!channel_ids) + return -ENOMEM; + rc = mpxy_get_channel_ids(mbox->channel_count, channel_ids); + if (rc) + return dev_err_probe(mbox->dev, rc, "failed to get MPXY channel IDs\n"); + + /* Populate all channels */ + mbox->channels = devm_kcalloc(mbox->dev, mbox->channel_count, + sizeof(*mbox->channels), GFP_KERNEL); + if (!mbox->channels) + return -ENOMEM; + for (i = 0; i < mbox->channel_count; i++) { + mchan = &mbox->channels[i]; + mchan->mbox = mbox; + mchan->channel_id = channel_ids[i]; + + rc = mpxy_read_attrs(mchan->channel_id, SBI_MPXY_ATTR_MSG_PROT_ID, + sizeof(mchan->attrs) / sizeof(u32), + (u32 *)&mchan->attrs); + if (rc) { + return dev_err_probe(mbox->dev, rc, + "MPXY channel 0x%x read attrs failed\n", + mchan->channel_id); + } + + if (mchan->attrs.msg_proto_id == SBI_MPXY_MSGPROTO_RPMI_ID) { + rc = mpxy_mbox_read_rpmi_attrs(mchan); + if (rc) { + return dev_err_probe(mbox->dev, rc, + "MPXY channel 0x%x read RPMI attrs failed\n", + mchan->channel_id); + } + } + + mchan->notif = devm_kzalloc(mbox->dev, mpxy_shmem_size, GFP_KERNEL); + if (!mchan->notif) + return -ENOMEM; + + mchan->max_xfer_len = min(mpxy_shmem_size, mchan->attrs.msg_max_len); + + if ((mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS) && + (mchan->attrs.capability & SBI_MPXY_CHAN_CAP_EVENTS_STATE)) + mchan->have_events_state = true; + + if ((mchan->attrs.capability & SBI_MPXY_CHAN_CAP_GET_NOTIFICATIONS) && + (mchan->attrs.capability & SBI_MPXY_CHAN_CAP_MSI)) + mchan->msi_index = mbox->msi_count++; + else + mchan->msi_index = U32_MAX; + mchan->msi_irq = U32_MAX; + } + + return 0; +} + +static int mpxy_mbox_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mpxy_mbox_channel *mchan; + struct mpxy_mbox *mbox; + int msi_idx, rc; + u32 i; + + /* + * Initialize MPXY shared memory only once. This also ensures + * that SBI MPXY mailbox is probed only once. + */ + if (mpxy_shmem_init_done) { + dev_err(dev, "SBI MPXY mailbox already initialized\n"); + return -EALREADY; + } + + /* Probe for SBI MPXY extension */ + if (sbi_spec_version < sbi_mk_version(1, 0) || + sbi_probe_extension(SBI_EXT_MPXY) <= 0) { + dev_info(dev, "SBI MPXY extension not available\n"); + return -ENODEV; + } + + /* Find-out shared memory size */ + rc = mpxy_get_shmem_size(&mpxy_shmem_size); + if (rc) + return dev_err_probe(dev, rc, "failed to get MPXY shared memory size\n"); + + /* + * Setup MPXY shared memory on each CPU + * + * Note: Don't cleanup MPXY shared memory upon CPU power-down + * because the RPMI System MSI irqchip driver needs it to be + * available when migrating IRQs in CPU power-down path. + */ + cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/sbi-mpxy-shmem", + mpxy_setup_shmem, NULL); + + /* Mark as MPXY shared memory initialization done */ + mpxy_shmem_init_done = true; + + /* Allocate mailbox instance */ + mbox = devm_kzalloc(dev, sizeof(*mbox), GFP_KERNEL); + if (!mbox) + return -ENOMEM; + mbox->dev = dev; + platform_set_drvdata(pdev, mbox); + + /* Populate mailbox channels */ + rc = mpxy_mbox_populate_channels(mbox); + if (rc) + return rc; + + /* Initialize mailbox controller */ + mbox->controller.txdone_irq = false; + mbox->controller.txdone_poll = false; + mbox->controller.ops = &mpxy_mbox_ops; + mbox->controller.dev = dev; + mbox->controller.num_chans = mbox->channel_count; + mbox->controller.fw_xlate = mpxy_mbox_fw_xlate; + mbox->controller.chans = devm_kcalloc(dev, mbox->channel_count, + sizeof(*mbox->controller.chans), + GFP_KERNEL); + if (!mbox->controller.chans) + return -ENOMEM; + for (i = 0; i < mbox->channel_count; i++) + mbox->controller.chans[i].con_priv = &mbox->channels[i]; + + /* Setup MSIs for mailbox (if required) */ + if (mbox->msi_count) { + /* + * The device MSI domain for platform devices on RISC-V architecture + * is only available after the MSI controller driver is probed so, + * explicitly configure here. + */ + if (!dev_get_msi_domain(dev)) { + struct fwnode_handle *fwnode = dev_fwnode(dev); + + /* + * The device MSI domain for OF devices is only set at the + * time of populating/creating OF device. If the device MSI + * domain is discovered later after the OF device is created + * then we need to set it explicitly before using any platform + * MSI functions. + */ + if (is_of_node(fwnode)) { + of_msi_configure(dev, dev_of_node(dev)); + } else if (is_acpi_device_node(fwnode)) { + struct irq_domain *msi_domain; + + msi_domain = irq_find_matching_fwnode(imsic_acpi_get_fwnode(dev), + DOMAIN_BUS_PLATFORM_MSI); + dev_set_msi_domain(dev, msi_domain); + } + + if (!dev_get_msi_domain(dev)) + return -EPROBE_DEFER; + } + + mbox->msi_index_to_channel = devm_kcalloc(dev, mbox->msi_count, + sizeof(*mbox->msi_index_to_channel), + GFP_KERNEL); + if (!mbox->msi_index_to_channel) + return -ENOMEM; + + for (msi_idx = 0; msi_idx < mbox->msi_count; msi_idx++) { + for (i = 0; i < mbox->channel_count; i++) { + mchan = &mbox->channels[i]; + if (mchan->msi_index == msi_idx) { + mbox->msi_index_to_channel[msi_idx] = mchan; + break; + } + } + } + + rc = platform_device_msi_init_and_alloc_irqs(dev, mbox->msi_count, + mpxy_mbox_msi_write); + if (rc) { + return dev_err_probe(dev, rc, "Failed to allocate %d MSIs\n", + mbox->msi_count); + } + + for (i = 0; i < mbox->channel_count; i++) { + mchan = &mbox->channels[i]; + if (mchan->msi_index == U32_MAX) + continue; + mchan->msi_irq = msi_get_virq(dev, mchan->msi_index); + } + } + + /* Register mailbox controller */ + rc = devm_mbox_controller_register(dev, &mbox->controller); + if (rc) { + dev_err_probe(dev, rc, "Registering SBI MPXY mailbox failed\n"); + if (mbox->msi_count) + platform_device_msi_free_irqs_all(dev); + return rc; + } + +#ifdef CONFIG_ACPI + struct acpi_device *adev = ACPI_COMPANION(dev); + + if (adev) + acpi_dev_clear_dependencies(adev); +#endif + + dev_info(dev, "mailbox registered with %d channels\n", + mbox->channel_count); + return 0; +} + +static void mpxy_mbox_remove(struct platform_device *pdev) +{ + struct mpxy_mbox *mbox = platform_get_drvdata(pdev); + + if (mbox->msi_count) + platform_device_msi_free_irqs_all(mbox->dev); +} + +static const struct of_device_id mpxy_mbox_of_match[] = { + { .compatible = "riscv,sbi-mpxy-mbox" }, + {} +}; +MODULE_DEVICE_TABLE(of, mpxy_mbox_of_match); + +static const struct acpi_device_id mpxy_mbox_acpi_match[] = { + { "RSCV0005" }, + {} +}; +MODULE_DEVICE_TABLE(acpi, mpxy_mbox_acpi_match); + +static struct platform_driver mpxy_mbox_driver = { + .driver = { + .name = "riscv-sbi-mpxy-mbox", + .of_match_table = mpxy_mbox_of_match, + .acpi_match_table = mpxy_mbox_acpi_match, + }, + .probe = mpxy_mbox_probe, + .remove = mpxy_mbox_remove, +}; +module_platform_driver(mpxy_mbox_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Anup Patel <apatel@ventanamicro.com>"); +MODULE_DESCRIPTION("RISC-V SBI MPXY mailbox controller driver"); |