Good day, On Fri, Nov 21, 2025 at 02:21:57PM +0000, Valentina Fernandez wrote: > Microchip family of RISC-V SoCs typically have one or more > clusters. These clusters can be configured to run in an Asymmetric > Multi Processing (AMP) mode where clusters are split in independent > software contexts. > > Add a remoteproc platform driver to be able to load and boot firmware > to remote processors. > > The driver uses SBI (RISC-V Supervisor Binary Interface) ecalls to > request software running in machine privilege mode (M-mode) to > start/stop the remote processor. > > Inter-processor communication is supported through the > virtio rpmsg stack using shared memory and the Microchip IPC mailbox > driver. > > Currently, the driver the following features are supported: > - Start/stop a remote software context > - Kick function implementation for RPMsg Communication > - Attach to a remote context loaded by another entity (bootloader) > > Error Recovery and Power Management features are not currently supported. > > Signed-off-by: Valentina Fernandez <[email protected]> > --- > drivers/remoteproc/Kconfig | 12 + > drivers/remoteproc/Makefile | 1 + > drivers/remoteproc/mchp_ipc_sbi_remoteproc.c | 465 +++++++++++++++++++ > 3 files changed, 478 insertions(+) > create mode 100644 drivers/remoteproc/mchp_ipc_sbi_remoteproc.c > > diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig > index 48a0d3a69ed0..68bd68f553ea 100644 > --- a/drivers/remoteproc/Kconfig > +++ b/drivers/remoteproc/Kconfig > @@ -54,6 +54,18 @@ config INGENIC_VPU_RPROC > This can be either built-in or a loadable module. > If unsure say N. > > +config MCHP_IPC_SBI_REMOTEPROC > + tristate "Microchip IPC remoteproc support" > + depends on MCHP_SBI_IPC_MBOX || COMPILE_TEST > + depends on ARCH_MICROCHIP > + help > + Say y here to support booting and loading firmware to remote > + processors on various Microchip family of RISC-V SoCs via the > + remote processor framework. > + This can be either built-in or a loadable module.a
No line break needed. > + If compiled as module, the module will be called mchp_ipc_remoteproc. > + If unsure say N. > + > config MTK_SCP > tristate "Mediatek SCP support" > depends on ARCH_MEDIATEK || COMPILE_TEST > diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile > index 1c7598b8475d..afb28dff5666 100644 > --- a/drivers/remoteproc/Makefile > +++ b/drivers/remoteproc/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_REMOTEPROC_CDEV) += > remoteproc_cdev.o > obj-$(CONFIG_IMX_REMOTEPROC) += imx_rproc.o > obj-$(CONFIG_IMX_DSP_REMOTEPROC) += imx_dsp_rproc.o > obj-$(CONFIG_INGENIC_VPU_RPROC) += ingenic_rproc.o > +obj-$(CONFIG_MCHP_IPC_SBI_REMOTEPROC) += mchp_ipc_sbi_remoteproc.o Please drop the "ipc_sbi", it is redundant and doesn't any useful information. Here and everywhere in this file. > obj-$(CONFIG_MTK_SCP) += mtk_scp.o mtk_scp_ipi.o > obj-$(CONFIG_OMAP_REMOTEPROC) += omap_remoteproc.o > obj-$(CONFIG_WKUP_M3_RPROC) += wkup_m3_rproc.o > diff --git a/drivers/remoteproc/mchp_ipc_sbi_remoteproc.c > b/drivers/remoteproc/mchp_ipc_sbi_remoteproc.c > new file mode 100644 > index 000000000000..55d182c1eee7 > --- /dev/null > +++ b/drivers/remoteproc/mchp_ipc_sbi_remoteproc.c > @@ -0,0 +1,465 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Microchip IPC Remoteproc driver > + * > + * Copyright (c) 2021 - 2025 Microchip Technology Inc. All rights reserved. > + * > + * Author: Valentina Fernandez <[email protected]> > + * > + * Derived from the imx_rproc implementation: > + * Copyright (c) 2017 Pengutronix, Oleksij Rempel <[email protected]> > + */ > + > +#include <linux/err.h> > +#include <linux/kernel.h> > +#include <linux/mailbox_client.h> > +#include <linux/module.h> > +#include <linux/of_address.h> > +#include <linux/of_reserved_mem.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/remoteproc.h> > +#include <linux/workqueue.h> > + > +#include <asm/sbi.h> > +#include <asm/vendorid_list.h> > +#include <linux/mailbox/mchp-ipc.h> > + > +#include "remoteproc_internal.h" > + > +#define SBI_EXT_MICROCHIP_TECHNOLOGY (SBI_EXT_VENDOR_START | \ > + MICROCHIP_VENDOR_ID) > + > +#define MIV_RPROC_MEM_MAX 2 > + > +enum { > + SBI_EXT_RPROC_STATE = 0x3, > + SBI_EXT_RPROC_START, > + SBI_EXT_RPROC_STOP, > +}; > + > +/** > + * enum mchp_ipc_rproc_mbox_messages - predefined mailbox messages > + * > + * @MCHP_IPC_RPROC_MBOX_READY: a ready message response from a remote > context indicating > + * that the remote context is up and running. > + * > + * @MCHP_IPC_RPROC_MBOX_PENDING_MSG: Not currently in use, but reserved for > future use > + * to inform the receiver that there is a message awaiting in its > receive-side > + * vring. At the moment, one can explicitly send the index of the triggered > + * virtqueue as a payload. > + * > + * @MCHP_IPC_RPROC_MBOX_STOP: a stop request for the remote context > + * > + * @MCHP_IPC_RPROC_MBOX_END_MSG: Indicates end of known/defined messages. > + * This should be the last definition. > + * > + */ > +enum mchp_ipc_rproc_mbox_messages { > + MCHP_IPC_RPROC_MBOX_READY = 0xFFFFFF00, > + MCHP_IPC_RPROC_MBOX_PENDING_MSG = 0xFFFFFF01, > + MCHP_IPC_RPROC_MBOX_STOP = 0xFFFFFF02, > + MCHP_IPC_RPROC_MBOX_END_MSG = 0xFFFFFF03, > +}; > + > +enum { > + MCHP_IPC_RPROC_RSC_TABLE_REGION, > + MCHP_IPC_RPROC_FW_REGION, > + MCHP_IPC_RPROC_BUFF_REGION, > + MCHP_IPC_RPROC_VRING0_REGION, > + MCHP_IPC_RPROC_VRING1_REGION, > + MCHP_IPC_RPROC_REGION_MAX, > +}; > + > +struct mchp_ipc_rproc_mem_region { > + const char *name; > + const char *prefix; > +}; > + > +struct mchp_ipc_rproc { > + struct device *dev; > + struct rproc *rproc; > + struct mbox_chan *mbox_channel; > + struct workqueue_struct *workqueue; > + struct mbox_client mbox_client; > + struct completion start_done; > + struct work_struct rproc_work; > + struct mchp_ipc_msg message; > + void __iomem *rsc_table; > + bool initialized; > + u32 chan_id; > +}; > + > +static struct mchp_ipc_rproc_mem_region mchp_rproc_mem_regions[] = { > + [MCHP_IPC_RPROC_RSC_TABLE_REGION] = { > + .name = "rsc-table", > + .prefix = NULL, > + }, > + [MCHP_IPC_RPROC_FW_REGION] = { > + .name = "firmware", > + .prefix = NULL, > + }, > + [MCHP_IPC_RPROC_BUFF_REGION] = { > + .name = "buffer", > + .prefix = "vdev0", > + }, > + [MCHP_IPC_RPROC_VRING0_REGION] = { > + .name = "vring0", > + .prefix = "vdev0", > + }, > + [MCHP_IPC_RPROC_VRING1_REGION] = { > + .name = "vring1", > + .prefix = "vdev0", > + }, > +}; > + > +static int mchp_ipc_rproc_start(struct rproc *rproc) > +{ > + struct mchp_ipc_rproc *priv = rproc->priv; > + struct sbiret ret; > + > + ret = sbi_ecall(SBI_EXT_MICROCHIP_TECHNOLOGY, SBI_EXT_RPROC_START, > + priv->chan_id, rproc->bootaddr, 0, 0, 0, 0); > + > + if (ret.error) > + return sbi_err_map_linux_errno(ret.error); > + > + if (!wait_for_completion_timeout(&priv->start_done, > + msecs_to_jiffies(5000))) { > + dev_err(priv->dev, "timeout waiting for ready notification\n"); > + return -ETIMEDOUT; > + } > + > + return 0; > +} > + > +static int mchp_ipc_rproc_stop(struct rproc *rproc) > +{ > + struct mchp_ipc_rproc *priv = rproc->priv; > + struct sbiret ret; > + > + ret = sbi_ecall(SBI_EXT_MICROCHIP_TECHNOLOGY, SBI_EXT_RPROC_STOP, > + priv->chan_id, MCHP_IPC_RPROC_MBOX_STOP, 0, 0, 0, 0); > + > + if (ret.error) > + return sbi_err_map_linux_errno(ret.error); > + > + return ret.value; > +} > + > +static int mchp_ipc_rproc_mem_alloc(struct rproc *rproc, struct > rproc_mem_entry *mem) > +{ > + struct device *dev = rproc->dev.parent; > + void *va; > + > + dev_dbg(dev, "map memory: %pad+%zx\n", &mem->dma, mem->len); > + va = ioremap_wc(mem->dma, mem->len); > + if (IS_ERR_OR_NULL(va)) { > + dev_err(dev, "Unable to map memory region: %p+%zx\n", > + &mem->dma, mem->len); > + return -ENOMEM; > + } > + > + mem->va = va; > + > + return 0; > +} > + > +static int mchp_ipc_rproc_mem_release(struct rproc *rproc, > + struct rproc_mem_entry *mem) > +{ > + dev_dbg(rproc->dev.parent, "unmap memory: %pad\n", &mem->dma); > + iounmap(mem->va); > + > + return 0; > +} > + > +static int mchp_ipc_rproc_prepare(struct rproc *rproc) > +{ > + struct mchp_ipc_rproc *priv = rproc->priv; > + struct device_node *np = priv->dev->of_node; > + struct rproc_mem_entry *mem; > + struct resource res; > + int i, ret; > + > + reinit_completion(&priv->start_done); > + > + for (i = 0; i < ARRAY_SIZE(mchp_rproc_mem_regions); i++) { > + char *mem_region_name = devm_kstrdup(priv->dev, > + > mchp_rproc_mem_regions[i].name, GFP_KERNEL); > + int index = of_property_match_string(np, "memory-region-names", > mem_region_name); > + > + if (index < 0) > + continue; > + > + ret = of_reserved_mem_region_to_resource_byname(np, > mem_region_name, &res); > + if (ret) > + return ret; > + > + if (mchp_rproc_mem_regions[i].prefix) { > + mem_region_name = devm_kasprintf(priv->dev, GFP_KERNEL, > "%s%s", > + > mchp_rproc_mem_regions[i].prefix, > + mem_region_name); > + } > + > + if (i == MCHP_IPC_RPROC_BUFF_REGION) { > + mem = rproc_of_resm_mem_entry_init(priv->dev, index, > resource_size(&res), > + res.start, > mem_region_name); > + } else { > + mem = rproc_mem_entry_init(priv->dev, NULL, > + (dma_addr_t)res.start, > + resource_size(&res), > res.start, > + mchp_ipc_rproc_mem_alloc, > + mchp_ipc_rproc_mem_release, > + mem_region_name); > + } > + rproc_add_carveout(rproc, mem); > + } > + > + return 0; > +} > + > +static int mchp_ipc_rproc_parse_fw(struct rproc *rproc, const struct > firmware *fw) > +{ > + int ret; > + > + ret = rproc_elf_load_rsc_table(rproc, fw); > + if (ret) > + dev_info(&rproc->dev, "No resource table in elf\n"); > + > + return 0; > +} > + > +static void mchp_ipc_rproc_kick(struct rproc *rproc, int vqid) > +{ > + struct mchp_ipc_rproc *priv = (struct mchp_ipc_rproc *)rproc->priv; > + struct mchp_ipc_msg msg; > + int ret; > + > + msg.buf = (void *)&vqid; > + msg.size = sizeof(vqid); > + > + ret = mbox_send_message(priv->mbox_channel, (void *)&msg); > + if (ret < 0) > + dev_err(priv->dev, > + "failed to send mbox message, status = %d\n", ret); > +} > + > +static int mchp_ipc_rproc_attach(struct rproc *rproc) > +{ > + return 0; > +} > + > +static struct resource_table > +*mchp_ipc_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz) > +{ > + struct mchp_ipc_rproc *priv = rproc->priv; > + > + if (!priv->rsc_table) > + return NULL; > + > + *table_sz = SZ_1K; > + return (struct resource_table *)priv->rsc_table; > +} > + > +static const struct rproc_ops mchp_ipc_rproc_ops = { > + .prepare = mchp_ipc_rproc_prepare, > + .start = mchp_ipc_rproc_start, > + .get_loaded_rsc_table = mchp_ipc_rproc_get_loaded_rsc_table, > + .attach = mchp_ipc_rproc_attach, > + .stop = mchp_ipc_rproc_stop, > + .kick = mchp_ipc_rproc_kick, > + .load = rproc_elf_load_segments, > + .parse_fw = mchp_ipc_rproc_parse_fw, > + .find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table, > + .sanity_check = rproc_elf_sanity_check, > + .get_boot_addr = rproc_elf_get_boot_addr, > +}; > + > +static void mchp_ipc_rproc_vq_work(struct work_struct *work) > +{ > + struct mchp_ipc_rproc *priv = container_of(work, struct mchp_ipc_rproc, > rproc_work); > + struct device *dev = priv->rproc->dev.parent; > + > + u32 msg = priv->message.buf[0]; > + > + /* > + * Currently, we are expected to receive the following messages > + * from the remote cluster: a ready message or receive the index > + * of the triggered virtqueue as a payload. > + * We can silently ignore any other type of mailbox messages since > + * they are not meant for us and are meant to be received by the > + * remote cluster only. > + */ > + switch (msg) { > + case MCHP_IPC_RPROC_MBOX_READY: > + complete(&priv->start_done); > + break; > + default: > + if (msg >= MCHP_IPC_RPROC_MBOX_READY && msg < > MCHP_IPC_RPROC_MBOX_END_MSG) The condition (msg == MCHP_IPC_RPROC_MBOX_READY) is already checked as part of the previous case statement. If you need to repeat this check, the design of the case state likely needs more work. > + return; > + if (msg > priv->rproc->max_notifyid) { > + dev_info(dev, "dropping unknown message 0x%x", msg); > + return; > + } > + /* msg contains the index of the triggered vring */ > + if (rproc_vq_interrupt(priv->rproc, msg) == IRQ_NONE) > + dev_dbg(dev, "no message was found in vqid %d\n", msg); > + } > +} > + > +static void mchp_ipc_rproc_rx_callback(struct mbox_client *mbox_client, void > *msg) > +{ > + struct rproc *rproc = dev_get_drvdata(mbox_client->dev); > + struct mchp_ipc_rproc *priv = rproc->priv; > + > + priv->message = *(struct mchp_ipc_msg *)msg; > + queue_work(priv->workqueue, &priv->rproc_work); > +} > + > +static int mchp_ipc_rproc_mbox_init(struct rproc *rproc) > +{ > + struct mchp_ipc_rproc *priv = rproc->priv; > + struct device *dev = priv->dev; > + struct mchp_ipc_sbi_chan *chan_priv; > + struct mbox_client *mbox_client; > + > + mbox_client = &priv->mbox_client; > + mbox_client->dev = dev; > + mbox_client->tx_block = true; > + mbox_client->tx_tout = 100; > + mbox_client->knows_txdone = false; > + mbox_client->rx_callback = mchp_ipc_rproc_rx_callback; > + > + priv->mbox_channel = mbox_request_channel(mbox_client, 0); > + if (IS_ERR(priv->mbox_channel)) > + return dev_err_probe(mbox_client->dev, > + PTR_ERR(priv->mbox_channel), > + "failed to request mailbox channel\n"); > + > + chan_priv = (struct mchp_ipc_sbi_chan *)priv->mbox_channel->con_priv; Where is the memory for ->con_priv allocated? > + priv->chan_id = chan_priv->id; > + > + return 0; > +} > + > +static int mchp_ipc_rproc_get_state(u32 chan) > +{ > + struct sbiret ret; > + > + ret = sbi_ecall(SBI_EXT_MICROCHIP_TECHNOLOGY, SBI_EXT_RPROC_STATE, > + chan, 0, 0, 0, 0, 0); > + > + if (ret.error) > + return sbi_err_map_linux_errno(ret.error); > + > + return ret.value; > +} > + > +static int mchp_ipc_rproc_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct device_node *np = dev->of_node; > + struct mchp_ipc_rproc *priv; > + struct rproc *rproc; > + struct resource res; > + int num_rmems, ret; > + > + rproc = devm_rproc_alloc(dev, np->name, &mchp_ipc_rproc_ops, > + NULL, sizeof(*priv)); > + if (!rproc) > + return -ENOMEM; > + > + priv = rproc->priv; > + priv->rproc = rproc; > + priv->dev = dev; > + > + num_rmems = of_property_count_elems_of_size(np, "memory-region", > + sizeof(phandle)); Please add a comment to describe why a minimum of 1 memory region is needed. Otherwise I have to guess. > + if (num_rmems < 1) > + return dev_err_probe(dev, -EINVAL, > + "device needs at least one memory regions > to be defined\n"); > + > + ret = of_reserved_mem_region_to_resource_byname(np, "rsc-table", &res); > + if (!ret) { > + priv->rsc_table = devm_ioremap_resource(dev, &res); > + if (IS_ERR(priv->rsc_table)) { > + return dev_err_probe(dev, PTR_ERR(priv->rsc_table), > + "failed to map resource table\n"); > + } > + } The above makes me suspicious but I currently don't have time to look in the rproc_ops for answers. You can either spin off a new revision to address the comments already received or wait for me to look at the rproc_ops in January - the choice is yours. Thanks, Mathieu > + > + priv->workqueue = create_workqueue(dev_name(dev)); > + if (!priv->workqueue) > + return dev_err_probe(dev, -ENOMEM, "cannot create workqueue\n"); > + > + INIT_WORK(&priv->rproc_work, mchp_ipc_rproc_vq_work); > + init_completion(&priv->start_done); > + > + ret = mchp_ipc_rproc_mbox_init(rproc); > + if (ret) > + goto err_put_wkq; > + > + /* > + * Check if the remote cluster has been booted by another entity > + * (i.e. bootloader) and set rproc state accordingly > + */ > + rproc->state = mchp_ipc_rproc_get_state(priv->chan_id); > + if (ret < 0) { > + dev_err_probe(dev, ret, "Couldn't get cluster boot mode\n"); > + goto err_put_mbox; > + } > + > + if (rproc->state != RPROC_DETACHED) > + rproc->auto_boot = false; > + > + /* error recovery is not supported at present */ > + rproc->recovery_disabled = true; > + > + dev_set_drvdata(dev, rproc); > + > + ret = devm_rproc_add(dev, rproc); > + if (ret) { > + dev_err_probe(dev, ret, "rproc_add failed\n"); > + goto err_put_mbox; > + } > + > + return 0; > + > +err_put_mbox: > + mbox_free_channel(priv->mbox_channel); > +err_put_wkq: > + destroy_workqueue(priv->workqueue); > + > + return ret; > +} > + > +static void mchp_ipc_rproc_remove(struct platform_device *pdev) > +{ > + struct rproc *rproc = platform_get_drvdata(pdev); > + struct mchp_ipc_rproc *priv = rproc->priv; > + > + mbox_free_channel(priv->mbox_channel); > + destroy_workqueue(priv->workqueue); > +} > + > +static const struct of_device_id mchp_ipc_rproc_of_match[] __maybe_unused = { > + { .compatible = "microchip,ipc-sbi-remoteproc", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, mchp_ipc_rproc_of_match); > + > +static struct platform_driver mchp_ipc_rproc_driver = { > + .probe = mchp_ipc_rproc_probe, > + .remove = mchp_ipc_rproc_remove, > + .driver = { > + .name = "microchip-ipc-rproc", > + .of_match_table = of_match_ptr(mchp_ipc_rproc_of_match), > + }, > +}; > + > +module_platform_driver(mchp_ipc_rproc_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Valentina Fernandez > <[email protected]>"); > +MODULE_DESCRIPTION("Microchip IPC Remote Processor control driver"); > -- > 2.34.1 >

