This adds a driver to communicate with the APU available in the mt8183. The driver is generic and could be used for other APU. It mostly provides a userspace interface to send messages and and share big buffers with the APU.
Signed-off-by: Alexandre Bailon abailon@baylibre.com --- drivers/rpmsg/Kconfig | 9 + drivers/rpmsg/Makefile | 1 + drivers/rpmsg/apu_rpmsg.c | 606 +++++++++++++++++++++++++++++++++ drivers/rpmsg/apu_rpmsg.h | 52 +++ include/uapi/linux/apu_rpmsg.h | 36 ++ 5 files changed, 704 insertions(+) create mode 100644 drivers/rpmsg/apu_rpmsg.c create mode 100644 drivers/rpmsg/apu_rpmsg.h create mode 100644 include/uapi/linux/apu_rpmsg.h
diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig index f96716893c2a..3437c6fc8647 100644 --- a/drivers/rpmsg/Kconfig +++ b/drivers/rpmsg/Kconfig @@ -64,4 +64,13 @@ config RPMSG_VIRTIO select RPMSG select VIRTIO
+config RPMSG_APU + tristate "APU RPMSG driver" + help + This provides a RPMSG driver that provides some facilities to + communicate with an accelerated processing unit (APU). + This creates one or more char files that could be used by userspace + to send a message to an APU. In addition, this also take care of + sharing the memory buffer with the APU. + endmenu diff --git a/drivers/rpmsg/Makefile b/drivers/rpmsg/Makefile index ffe932ef6050..93e0f3de99c9 100644 --- a/drivers/rpmsg/Makefile +++ b/drivers/rpmsg/Makefile @@ -8,3 +8,4 @@ obj-$(CONFIG_RPMSG_QCOM_GLINK_RPM) += qcom_glink_rpm.o obj-$(CONFIG_RPMSG_QCOM_GLINK_SMEM) += qcom_glink_smem.o obj-$(CONFIG_RPMSG_QCOM_SMD) += qcom_smd.o obj-$(CONFIG_RPMSG_VIRTIO) += virtio_rpmsg_bus.o +obj-$(CONFIG_RPMSG_APU) += apu_rpmsg.o diff --git a/drivers/rpmsg/apu_rpmsg.c b/drivers/rpmsg/apu_rpmsg.c new file mode 100644 index 000000000000..5131b8b8e1f2 --- /dev/null +++ b/drivers/rpmsg/apu_rpmsg.c @@ -0,0 +1,606 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright 2020 BayLibre SAS + +#include <linux/cdev.h> +#include <linux/dma-buf.h> +#include <linux/iommu.h> +#include <linux/iova.h> +#include <linux/types.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/remoteproc.h> +#include <linux/rpmsg.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include "rpmsg_internal.h" + +#include <uapi/linux/apu_rpmsg.h> + +#include "apu_rpmsg.h" + +/* Maximum of APU devices supported */ +#define APU_DEV_MAX 2 + +#define dev_to_apu(dev) container_of(dev, struct rpmsg_apu, dev) +#define cdev_to_apu(i_cdev) container_of(i_cdev, struct rpmsg_apu, cdev) + +struct rpmsg_apu { + struct rpmsg_device *rpdev; + struct cdev cdev; + struct device dev; + + struct rproc *rproc; + struct iommu_domain *domain; + struct iova_domain *iovad; + int iova_limit_pfn; +}; + +struct rpmsg_request { + struct completion completion; + struct list_head node; + void *req; +}; + +struct apu_buffer { + int fd; + struct dma_buf *dma_buf; + struct dma_buf_attachment *attachment; + struct sg_table *sg_table; + u32 iova; +}; + +/* + * Shared IOVA domain. + * The MT8183 has two VP6 core but they are sharing the IOVA. + * They could be used alone, or together. In order to avoid conflict, + * create an IOVA domain that could be shared by those two core. + * @iovad: The IOVA domain to share between the APU cores + * @refcount: Allow to automatically release the IOVA domain once all the APU + * cores has been stopped + */ +struct apu_iova_domain { + struct iova_domain iovad; + struct kref refcount; +}; + +static dev_t rpmsg_major; +static DEFINE_IDA(rpmsg_ctrl_ida); +static DEFINE_IDA(rpmsg_minor_ida); +static DEFINE_IDA(req_ida); +static LIST_HEAD(requests); +static struct apu_iova_domain *apu_iovad; + +static int apu_rpmsg_callback(struct rpmsg_device *dev, void *data, int count, + void *priv, u32 addr) +{ + struct rpmsg_request *rpmsg_req; + struct apu_dev_request *hdr = data; + + list_for_each_entry(rpmsg_req, &requests, node) { + struct apu_dev_request *tmp_hdr = rpmsg_req->req; + + if (hdr->id == tmp_hdr->id) { + memcpy(rpmsg_req->req, data, count); + complete(&rpmsg_req->completion); + + return 0; + } + } + + return 0; +} + +static int apu_device_memory_map(struct rpmsg_apu *apu, + struct apu_buffer *buffer) +{ + struct rpmsg_device *rpdev = apu->rpdev; + phys_addr_t phys; + int total_buf_space; + int iova_pfn; + int ret; + + if (!buffer->fd) + return 0; + + buffer->dma_buf = dma_buf_get(buffer->fd); + if (IS_ERR(buffer->dma_buf)) { + dev_err(&rpdev->dev, "Failed to get dma_buf from fd: %ld\n", + PTR_ERR(buffer->dma_buf)); + return PTR_ERR(buffer->dma_buf); + } + + buffer->attachment = dma_buf_attach(buffer->dma_buf, &rpdev->dev); + if (IS_ERR(buffer->attachment)) { + dev_err(&rpdev->dev, "Failed to attach dma_buf\n"); + ret = PTR_ERR(buffer->attachment); + goto err_dma_buf_put; + } + + buffer->sg_table = dma_buf_map_attachment(buffer->attachment, + DMA_BIDIRECTIONAL); + if (IS_ERR(buffer->sg_table)) { + dev_err(&rpdev->dev, "Failed to map attachment\n"); + ret = PTR_ERR(buffer->sg_table); + goto err_dma_buf_detach; + } + phys = page_to_phys(sg_page(buffer->sg_table->sgl)); + total_buf_space = sg_dma_len(buffer->sg_table->sgl); + + iova_pfn = alloc_iova_fast(apu->iovad, total_buf_space >> PAGE_SHIFT, + apu->iova_limit_pfn, true); + if (!iova_pfn) { + dev_err(&rpdev->dev, "Failed to allocate iova address\n"); + ret = -ENOMEM; + goto err_dma_unmap_attachment; + } + + buffer->iova = PFN_PHYS(iova_pfn); + ret = iommu_map(apu->rproc->domain, buffer->iova, phys, total_buf_space, + IOMMU_READ | IOMMU_WRITE | IOMMU_CACHE); + if (ret) { + dev_err(&rpdev->dev, "Failed to iommu map\n"); + goto err_free_iova; + } + + return 0; + +err_free_iova: + free_iova(apu->iovad, iova_pfn); +err_dma_unmap_attachment: + dma_buf_unmap_attachment(buffer->attachment, + buffer->sg_table, + DMA_BIDIRECTIONAL); +err_dma_buf_detach: + dma_buf_detach(buffer->dma_buf, buffer->attachment); +err_dma_buf_put: + dma_buf_put(buffer->dma_buf); + + return ret; +} + +static void apu_device_memory_unmap(struct rpmsg_apu *apu, + struct apu_buffer *buffer) +{ + int total_buf_space; + + if (!buffer->fd) + return; + + total_buf_space = sg_dma_len(buffer->sg_table->sgl); + iommu_unmap(apu->rproc->domain, buffer->iova, total_buf_space); + free_iova(apu->iovad, PHYS_PFN(buffer->iova)); + dma_buf_unmap_attachment(buffer->attachment, + buffer->sg_table, + DMA_BIDIRECTIONAL); + dma_buf_detach(buffer->dma_buf, buffer->attachment); + dma_buf_put(buffer->dma_buf); +} + +static int _apu_send_request(struct rpmsg_apu *apu, + struct rpmsg_device *rpdev, + struct apu_dev_request *req, int len) +{ + + struct rpmsg_request *rpmsg_req; + int ret = 0; + + req->id = ida_simple_get(&req_ida, 0, 0xffff, GFP_KERNEL); + if (req->id < 0) + return ret; + + rpmsg_req = kzalloc(sizeof(*rpmsg_req), GFP_KERNEL); + if (!rpmsg_req) + return -ENOMEM; + + rpmsg_req->req = req; + init_completion(&rpmsg_req->completion); + list_add(&rpmsg_req->node, &requests); + + ret = rpmsg_send(rpdev->ept, req, len); + if (ret) + goto free_req; + + /* be careful with race here between timeout and callback*/ + ret = wait_for_completion_timeout(&rpmsg_req->completion, + msecs_to_jiffies(1000)); + if (!ret) + ret = -ETIMEDOUT; + else + ret = 0; + + ida_simple_remove(&req_ida, req->id); + +free_req: + + list_del(&rpmsg_req->node); + kfree(rpmsg_req); + + return ret; +} + +static int apu_send_request(struct rpmsg_apu *apu, + struct apu_request *req) +{ + int ret; + struct rpmsg_device *rpdev = apu->rpdev; + struct apu_dev_request *dev_req; + struct apu_buffer *buffer; + + int size = req->size_in + req->size_out + + sizeof(u32) * req->count * 2 + sizeof(*dev_req); + u32 *fd = (u32 *)(req->data + req->size_in + req->size_out); + u32 *buffer_size = (u32 *)(fd + req->count); + u32 *dev_req_da; + u32 *dev_req_buffer_size; + int i; + + dev_req = kmalloc(size, GFP_KERNEL); + if (!dev_req) + return -ENOMEM; + + dev_req->cmd = req->cmd; + dev_req->size_in = req->size_in; + dev_req->size_out = req->size_out; + dev_req->count = req->count; + dev_req_da = (u32 *)(dev_req->data + req->size_in + req->size_out); + dev_req_buffer_size = (u32 *)(dev_req_da + dev_req->count); + memcpy(dev_req->data, req->data, req->size_in); + + buffer = kmalloc_array(req->count, sizeof(*buffer), GFP_KERNEL); + for (i = 0; i < req->count; i++) { + buffer[i].fd = fd[i]; + ret = apu_device_memory_map(apu, &buffer[i]); + if (ret) + goto err_free_memory; + dev_req_da[i] = buffer[i].iova; + dev_req_buffer_size[i] = buffer_size[i]; + } + + ret = _apu_send_request(apu, rpdev, dev_req, size); + +err_free_memory: + for (i--; i >= 0; i--) + apu_device_memory_unmap(apu, &buffer[i]); + + req->result = dev_req->result; + req->size_in = dev_req->size_in; + req->size_out = dev_req->size_out; + memcpy(req->data, dev_req->data, dev_req->size_in + dev_req->size_out + + sizeof(u32) * req->count); + + kfree(buffer); + kfree(dev_req); + + return ret; +} + + +static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + struct rpmsg_apu *apu = fp->private_data; + struct apu_request apu_req; + struct apu_request *apu_req_full; + void __user *argp = (void __user *)arg; + int len; + int ret; + + switch (cmd) { + case APU_SEND_REQ_IOCTL: + /* Get the header */ + if (copy_from_user(&apu_req, argp, + sizeof(apu_req))) + return -EFAULT; + + len = sizeof(*apu_req_full) + apu_req.size_in + + apu_req.size_out + apu_req.count * sizeof(u32) * 2; + apu_req_full = kzalloc(len, GFP_KERNEL); + if (!apu_req_full) + return -ENOMEM; + + /* Get the whole request */ + if (copy_from_user(apu_req_full, argp, len)) { + kfree(apu_req_full); + return -EFAULT; + } + + ret = apu_send_request(apu, apu_req_full); + if (ret) { + kfree(apu_req_full); + return ret; + } + + if (copy_to_user(argp, apu_req_full, sizeof(apu_req) + + sizeof(u32) * apu_req_full->count + + apu_req_full->size_in + apu_req_full->size_out)) + ret = -EFAULT; + + kfree(apu_req_full); + return ret; + + default: + return -EINVAL; + } + + return 0; +} + +static int rpmsg_eptdev_open(struct inode *inode, struct file *filp) +{ + struct rpmsg_apu *apu = cdev_to_apu(inode->i_cdev); + + get_device(&apu->dev); + filp->private_data = apu; + + return 0; +} + +static int rpmsg_eptdev_release(struct inode *inode, struct file *filp) +{ + struct rpmsg_apu *apu = cdev_to_apu(inode->i_cdev); + + put_device(&apu->dev); + + return 0; +} + +static const struct file_operations rpmsg_eptdev_fops = { + .owner = THIS_MODULE, + .open = rpmsg_eptdev_open, + .release = rpmsg_eptdev_release, + .unlocked_ioctl = rpmsg_eptdev_ioctl, + .compat_ioctl = rpmsg_eptdev_ioctl, +}; + +static void iova_domain_release(struct kref *ref) +{ + put_iova_domain(&apu_iovad->iovad); + kfree(apu_iovad); + apu_iovad = NULL; +} + +static struct fw_rsc_iova *apu_find_rcs_iova(struct rpmsg_apu *apu) +{ + struct rproc *rproc = apu->rproc; + struct resource_table *table; + struct fw_rsc_iova *rsc; + int i; + + table = rproc->table_ptr; + for (i = 0; i < table->num; i++) { + int offset = table->offset[i]; + struct fw_rsc_hdr *hdr = (void *)table + offset; + + switch (hdr->type) { + case RSC_VENDOR_IOVA: + rsc = (void *)hdr + sizeof(*hdr); + return rsc; + break; + default: + continue; + } + } + + return NULL; +} + +static int apu_reserve_iova(struct rpmsg_apu *apu, struct iova_domain *iovad) +{ + struct rproc *rproc = apu->rproc; + struct resource_table *table; + struct fw_rsc_carveout *rsc; + int i; + + table = rproc->table_ptr; + for (i = 0; i < table->num; i++) { + int offset = table->offset[i]; + struct fw_rsc_hdr *hdr = (void *)table + offset; + + if (hdr->type == RSC_CARVEOUT) { + struct iova *iova; + + rsc = (void *)hdr + sizeof(*hdr); + iova = reserve_iova(iovad, PHYS_PFN(rsc->da), + PHYS_PFN(rsc->da + rsc->len)); + if (!iova) { + dev_err(&apu->dev, "failed to reserve iova\n"); + return -ENOMEM; + } + dev_dbg(&apu->dev, "Reserve: %x - %x\n", + rsc->da, rsc->da + rsc->len); + } + } + + return 0; +} + +static int apu_init_iovad(struct rpmsg_apu *apu) +{ + struct fw_rsc_iova *rsc; + + if (!apu->rproc->table_ptr) { + dev_err(&apu->dev, + "No resource_table: has the firmware been loaded ?\n"); + return -ENODEV; + } + + rsc = apu_find_rcs_iova(apu); + if (!rsc) { + dev_err(&apu->dev, "No iova range defined in resource_table\n"); + return -ENOMEM; + } + + if (!apu_iovad) { + apu_iovad = kzalloc(sizeof(*apu_iovad), GFP_KERNEL); + if (!apu_iovad) + return -ENOMEM; + + init_iova_domain(&apu_iovad->iovad, PAGE_SIZE, + PHYS_PFN(rsc->da)); + apu_reserve_iova(apu, &apu_iovad->iovad); + kref_init(&apu_iovad->refcount); + } else + kref_get(&apu_iovad->refcount); + + apu->iovad = &apu_iovad->iovad; + apu->iova_limit_pfn = PHYS_PFN(rsc->da + rsc->len) - 1; + + return 0; +} + +static struct rproc *apu_get_rproc(struct rpmsg_device *rpdev) +{ + /* + * To work, the APU RPMsg driver need to get the rproc device. + * Currently, we only use virtio so we could use that to find the + * remoteproc parent. + */ + if (!rpdev->dev.parent && rpdev->dev.parent->bus) { + dev_err(&rpdev->dev, "invalid rpmsg device\n"); + return ERR_PTR(-EINVAL); + } + + if (strcmp(rpdev->dev.parent->bus->name, "virtio")) { + dev_err(&rpdev->dev, "unsupported bus\n"); + return ERR_PTR(-EINVAL); + } + + return vdev_to_rproc(dev_to_virtio(rpdev->dev.parent)); +} + +static void rpmsg_apu_release_device(struct device *dev) +{ + struct rpmsg_apu *apu = dev_to_apu(dev); + + ida_simple_remove(&rpmsg_ctrl_ida, dev->id); + ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt)); + cdev_del(&apu->cdev); + kfree(apu); +} + +static int apu_rpmsg_probe(struct rpmsg_device *rpdev) +{ + struct rpmsg_apu *apu; + struct device *dev; + int ret; + + apu = devm_kzalloc(&rpdev->dev, sizeof(*apu), GFP_KERNEL); + if (!apu) + return -ENOMEM; + apu->rpdev = rpdev; + + apu->rproc = apu_get_rproc(rpdev); + if (IS_ERR_OR_NULL(apu->rproc)) + return PTR_ERR(apu->rproc); + + dev = &apu->dev; + device_initialize(dev); + dev->parent = &rpdev->dev; + + cdev_init(&apu->cdev, &rpmsg_eptdev_fops); + apu->cdev.owner = THIS_MODULE; + + ret = ida_simple_get(&rpmsg_minor_ida, 0, APU_DEV_MAX, GFP_KERNEL); + if (ret < 0) + goto free_apu; + dev->devt = MKDEV(MAJOR(rpmsg_major), ret); + + ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + goto free_minor_ida; + dev->id = ret; + dev_set_name(&apu->dev, "apu%d", ret); + + ret = cdev_add(&apu->cdev, dev->devt, 1); + if (ret) + goto free_ctrl_ida; + + /* We can now rely on the release function for cleanup */ + dev->release = rpmsg_apu_release_device; + + ret = device_add(dev); + if (ret) { + dev_err(&rpdev->dev, "device_add failed: %d\n", ret); + put_device(dev); + } + + /* Make device dma capable by inheriting from parent's capabilities */ + set_dma_ops(&rpdev->dev, get_dma_ops(apu->rproc->dev.parent)); + + ret = dma_coerce_mask_and_coherent(&rpdev->dev, + dma_get_mask(apu->rproc->dev.parent)); + if (ret) + goto err_put_device; + + rpdev->dev.iommu_group = apu->rproc->dev.parent->iommu_group; + + ret = apu_init_iovad(apu); + + dev_set_drvdata(&rpdev->dev, apu); + + return ret; + +err_put_device: + put_device(dev); +free_ctrl_ida: + ida_simple_remove(&rpmsg_ctrl_ida, dev->id); +free_minor_ida: + ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt)); +free_apu: + put_device(dev); + kfree(apu); + + return ret; +} + +static void apu_rpmsg_remove(struct rpmsg_device *rpdev) +{ + struct rpmsg_apu *apu = dev_get_drvdata(&rpdev->dev); + + if (apu_iovad) + kref_put(&apu_iovad->refcount, iova_domain_release); + + device_del(&apu->dev); + put_device(&apu->dev); + kfree(apu); +} + +static const struct rpmsg_device_id apu_rpmsg_match[] = { + { APU_RPMSG_SERVICE_MT8183 }, + {} +}; + +static struct rpmsg_driver apu_rpmsg_driver = { + .probe = apu_rpmsg_probe, + .remove = apu_rpmsg_remove, + .callback = apu_rpmsg_callback, + .id_table = apu_rpmsg_match, + .drv = { + .name = "apu_rpmsg", + }, +}; + +static int __init apu_rpmsg_init(void) +{ + int ret; + + ret = alloc_chrdev_region(&rpmsg_major, 0, APU_DEV_MAX, "apu"); + if (ret < 0) { + pr_err("apu: failed to allocate char dev region\n"); + return ret; + } + + return register_rpmsg_driver(&apu_rpmsg_driver); +} +arch_initcall(apu_rpmsg_init); + +static void __exit apu_rpmsg_exit(void) +{ + unregister_rpmsg_driver(&apu_rpmsg_driver); +} +module_exit(apu_rpmsg_exit); + + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("APU RPMSG driver"); diff --git a/drivers/rpmsg/apu_rpmsg.h b/drivers/rpmsg/apu_rpmsg.h new file mode 100644 index 000000000000..54b5b7880750 --- /dev/null +++ b/drivers/rpmsg/apu_rpmsg.h @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * Copyright 2020 BayLibre SAS + */ + +#ifndef __APU_RPMSG_H__ +#define __APU_RPMSG_H__ + +/* + * Firmware request, must be aligned with the one defined in firmware. + * @id: Request id, used in the case of reply, to find the pending request + * @cmd: The command id to execute in the firmware + * @result: The result of the command executed on the firmware + * @size: The size of the data available in this request + * @count: The number of shared buffer + * @data: Contains the data attached with the request if size is greater than + * zero, and the addresses of shared buffers if count is greater than + * zero. Both the data and the shared buffer could be read and write + * by the APU. + */ +struct apu_dev_request { + u16 id; + u16 cmd; + u16 result; + u16 size_in; + u16 size_out; + u16 count; + u8 data[0]; +} __packed; + +#define APU_RPMSG_SERVICE_MT8183 "rpmsg-mt8183-apu0" +#define APU_CTRL_SRC 1 +#define APU_CTRL_DST 1 + +/* Vendor specific resource table entry */ +#define RSC_VENDOR_IOVA 128 + +/* + * Firmware IOVA resource table entry + * Define a range of virtual device address that could mapped using the IOMMU. + * @da: Start virtual device address + * @len: Length of the virtual device address + * @name: name of the resource + */ +struct fw_rsc_iova { + u32 da; + u32 len; + u32 reserved; + u8 name[32]; +} __packed; + +#endif /* __APU_RPMSG_H__ */ diff --git a/include/uapi/linux/apu_rpmsg.h b/include/uapi/linux/apu_rpmsg.h new file mode 100644 index 000000000000..81c9e4af9a94 --- /dev/null +++ b/include/uapi/linux/apu_rpmsg.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright (c) 2020 BayLibre + */ + +#ifndef _UAPI_RPMSG_APU_H_ +#define _UAPI_RPMSG_APU_H_ + +#include <linux/ioctl.h> +#include <linux/types.h> + +/* + * Structure containing the APU request from userspace application + * @cmd: The id of the command to execute on the APU + * @result: The result of the command executed on the APU + * @size: The size of the data available in this request + * @count: The number of shared buffer + * @data: Contains the data attached with the request if size is greater than + * zero, and the files descriptors of shared buffers if count is greater + * than zero. Both the data and the shared buffer could be read and write + * by the APU. + */ +struct apu_request { + __u16 cmd; + __u16 result; + __u16 size_in; + __u16 size_out; + __u16 count; + __u16 reserved; + __u8 data[0]; +}; + +/* Send synchronous request to an APU */ +#define APU_SEND_REQ_IOCTL _IOWR(0xb7, 0x2, struct apu_request) + +#endif