// SPDX-License-Identifier: GPL-2.0-only /* * Arm Firmware Framework for ARMv8-A(FFA) interface driver * * The Arm FFA specification[1] describes a software architecture to * leverages the virtualization extension to isolate software images * provided by an ecosystem of vendors from each other and describes * interfaces that standardize communication between the various software * images including communication between images in the Secure world and * Normal world. Any Hypervisor could use the FFA interfaces to enable * communication between VMs it manages. * * The Hypervisor a.k.a Partition managers in FFA terminology can assign * system resources(Memory regions, Devices, CPU cycles) to the partitions * and manage isolation amongst them. * * [1] https://developer.arm.com/docs/den0077/latest * * Copyright (C) 2021 ARM Ltd. */ #define DRIVER_NAME "ARM FF-A" #define pr_fmt(fmt) DRIVER_NAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include "common.h" #define FFA_DRIVER_VERSION FFA_VERSION_1_0 #define FFA_SMC(calling_convention, func_num) \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, (calling_convention), \ ARM_SMCCC_OWNER_STANDARD, (func_num)) #define FFA_SMC_32(func_num) FFA_SMC(ARM_SMCCC_SMC_32, (func_num)) #define FFA_SMC_64(func_num) FFA_SMC(ARM_SMCCC_SMC_64, (func_num)) #define FFA_ERROR FFA_SMC_32(0x60) #define FFA_SUCCESS FFA_SMC_32(0x61) #define FFA_INTERRUPT FFA_SMC_32(0x62) #define FFA_VERSION FFA_SMC_32(0x63) #define FFA_FEATURES FFA_SMC_32(0x64) #define FFA_RX_RELEASE FFA_SMC_32(0x65) #define FFA_RXTX_MAP FFA_SMC_32(0x66) #define FFA_FN64_RXTX_MAP FFA_SMC_64(0x66) #define FFA_RXTX_UNMAP FFA_SMC_32(0x67) #define FFA_PARTITION_INFO_GET FFA_SMC_32(0x68) #define FFA_ID_GET FFA_SMC_32(0x69) #define FFA_MSG_POLL FFA_SMC_32(0x6A) #define FFA_MSG_WAIT FFA_SMC_32(0x6B) #define FFA_YIELD FFA_SMC_32(0x6C) #define FFA_RUN FFA_SMC_32(0x6D) #define FFA_MSG_SEND FFA_SMC_32(0x6E) #define FFA_MSG_SEND_DIRECT_REQ FFA_SMC_32(0x6F) #define FFA_FN64_MSG_SEND_DIRECT_REQ FFA_SMC_64(0x6F) #define FFA_MSG_SEND_DIRECT_RESP FFA_SMC_32(0x70) #define FFA_FN64_MSG_SEND_DIRECT_RESP FFA_SMC_64(0x70) #define FFA_MEM_DONATE FFA_SMC_32(0x71) #define FFA_FN64_MEM_DONATE FFA_SMC_64(0x71) #define FFA_MEM_LEND FFA_SMC_32(0x72) #define FFA_FN64_MEM_LEND FFA_SMC_64(0x72) #define FFA_MEM_SHARE FFA_SMC_32(0x73) #define FFA_FN64_MEM_SHARE FFA_SMC_64(0x73) #define FFA_MEM_RETRIEVE_REQ FFA_SMC_32(0x74) #define FFA_FN64_MEM_RETRIEVE_REQ FFA_SMC_64(0x74) #define FFA_MEM_RETRIEVE_RESP FFA_SMC_32(0x75) #define FFA_MEM_RELINQUISH FFA_SMC_32(0x76) #define FFA_MEM_RECLAIM FFA_SMC_32(0x77) #define FFA_MEM_OP_PAUSE FFA_SMC_32(0x78) #define FFA_MEM_OP_RESUME FFA_SMC_32(0x79) #define FFA_MEM_FRAG_RX FFA_SMC_32(0x7A) #define FFA_MEM_FRAG_TX FFA_SMC_32(0x7B) #define FFA_NORMAL_WORLD_RESUME FFA_SMC_32(0x7C) /* * For some calls it is necessary to use SMC64 to pass or return 64-bit values. * For such calls FFA_FN_NATIVE(name) will choose the appropriate * (native-width) function ID. */ #ifdef CONFIG_64BIT #define FFA_FN_NATIVE(name) FFA_FN64_##name #else #define FFA_FN_NATIVE(name) FFA_##name #endif /* FFA error codes. */ #define FFA_RET_SUCCESS (0) #define FFA_RET_NOT_SUPPORTED (-1) #define FFA_RET_INVALID_PARAMETERS (-2) #define FFA_RET_NO_MEMORY (-3) #define FFA_RET_BUSY (-4) #define FFA_RET_INTERRUPTED (-5) #define FFA_RET_DENIED (-6) #define FFA_RET_RETRY (-7) #define FFA_RET_ABORTED (-8) #define MAJOR_VERSION_MASK GENMASK(30, 16) #define MINOR_VERSION_MASK GENMASK(15, 0) #define MAJOR_VERSION(x) ((u16)(FIELD_GET(MAJOR_VERSION_MASK, (x)))) #define MINOR_VERSION(x) ((u16)(FIELD_GET(MINOR_VERSION_MASK, (x)))) #define PACK_VERSION_INFO(major, minor) \ (FIELD_PREP(MAJOR_VERSION_MASK, (major)) | \ FIELD_PREP(MINOR_VERSION_MASK, (minor))) #define FFA_VERSION_1_0 PACK_VERSION_INFO(1, 0) #define FFA_MIN_VERSION FFA_VERSION_1_0 #define SENDER_ID_MASK GENMASK(31, 16) #define RECEIVER_ID_MASK GENMASK(15, 0) #define SENDER_ID(x) ((u16)(FIELD_GET(SENDER_ID_MASK, (x)))) #define RECEIVER_ID(x) ((u16)(FIELD_GET(RECEIVER_ID_MASK, (x)))) #define PACK_TARGET_INFO(s, r) \ (FIELD_PREP(SENDER_ID_MASK, (s)) | FIELD_PREP(RECEIVER_ID_MASK, (r))) /* * FF-A specification mentions explicitly about '4K pages'. This should * not be confused with the kernel PAGE_SIZE, which is the translation * granule kernel is configured and may be one among 4K, 16K and 64K. */ #define FFA_PAGE_SIZE SZ_4K /* * Keeping RX TX buffer size as 4K for now * 64K may be preferred to keep it min a page in 64K PAGE_SIZE config */ #define RXTX_BUFFER_SIZE SZ_4K static ffa_fn *invoke_ffa_fn; static const int ffa_linux_errmap[] = { /* better than switch case as long as return value is continuous */ 0, /* FFA_RET_SUCCESS */ -EOPNOTSUPP, /* FFA_RET_NOT_SUPPORTED */ -EINVAL, /* FFA_RET_INVALID_PARAMETERS */ -ENOMEM, /* FFA_RET_NO_MEMORY */ -EBUSY, /* FFA_RET_BUSY */ -EINTR, /* FFA_RET_INTERRUPTED */ -EACCES, /* FFA_RET_DENIED */ -EAGAIN, /* FFA_RET_RETRY */ -ECANCELED, /* FFA_RET_ABORTED */ }; static inline int ffa_to_linux_errno(int errno) { int err_idx = -errno; if (err_idx >= 0 && err_idx < ARRAY_SIZE(ffa_linux_errmap)) return ffa_linux_errmap[err_idx]; return -EINVAL; } struct ffa_drv_info { u32 version; u16 vm_id; struct mutex rx_lock; /* lock to protect Rx buffer */ struct mutex tx_lock; /* lock to protect Tx buffer */ void *rx_buffer; void *tx_buffer; }; static struct ffa_drv_info *drv_info; /* * The driver must be able to support all the versions from the earliest * supported FFA_MIN_VERSION to the latest supported FFA_DRIVER_VERSION. * The specification states that if firmware supports a FFA implementation * that is incompatible with and at a greater version number than specified * by the caller(FFA_DRIVER_VERSION passed as parameter to FFA_VERSION), * it must return the NOT_SUPPORTED error code. */ static u32 ffa_compatible_version_find(u32 version) { u16 major = MAJOR_VERSION(version), minor = MINOR_VERSION(version); u16 drv_major = MAJOR_VERSION(FFA_DRIVER_VERSION); u16 drv_minor = MINOR_VERSION(FFA_DRIVER_VERSION); if ((major < drv_major) || (major == drv_major && minor <= drv_minor)) return version; pr_info("Firmware version higher than driver version, downgrading\n"); return FFA_DRIVER_VERSION; } static int ffa_version_check(u32 *version) { ffa_value_t ver; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_VERSION, .a1 = FFA_DRIVER_VERSION, }, &ver); if (ver.a0 == FFA_RET_NOT_SUPPORTED) { pr_info("FFA_VERSION returned not supported\n"); return -EOPNOTSUPP; } if (ver.a0 < FFA_MIN_VERSION) { pr_err("Incompatible v%d.%d! Earliest supported v%d.%d\n", MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0), MAJOR_VERSION(FFA_MIN_VERSION), MINOR_VERSION(FFA_MIN_VERSION)); return -EINVAL; } pr_info("Driver version %d.%d\n", MAJOR_VERSION(FFA_DRIVER_VERSION), MINOR_VERSION(FFA_DRIVER_VERSION)); pr_info("Firmware version %d.%d found\n", MAJOR_VERSION(ver.a0), MINOR_VERSION(ver.a0)); *version = ffa_compatible_version_find(ver.a0); return 0; } static int ffa_rx_release(void) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_RX_RELEASE, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); /* check for ret.a0 == FFA_RX_RELEASE ? */ return 0; } static int ffa_rxtx_map(phys_addr_t tx_buf, phys_addr_t rx_buf, u32 pg_cnt) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_FN_NATIVE(RXTX_MAP), .a1 = tx_buf, .a2 = rx_buf, .a3 = pg_cnt, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); return 0; } static int ffa_rxtx_unmap(u16 vm_id) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_RXTX_UNMAP, .a1 = PACK_TARGET_INFO(vm_id, 0), }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); return 0; } /* buffer must be sizeof(struct ffa_partition_info) * num_partitions */ static int __ffa_partition_info_get(u32 uuid0, u32 uuid1, u32 uuid2, u32 uuid3, struct ffa_partition_info *buffer, int num_partitions) { int count; ffa_value_t partition_info; mutex_lock(&drv_info->rx_lock); invoke_ffa_fn((ffa_value_t){ .a0 = FFA_PARTITION_INFO_GET, .a1 = uuid0, .a2 = uuid1, .a3 = uuid2, .a4 = uuid3, }, &partition_info); if (partition_info.a0 == FFA_ERROR) { mutex_unlock(&drv_info->rx_lock); return ffa_to_linux_errno((int)partition_info.a2); } count = partition_info.a2; if (buffer && count <= num_partitions) memcpy(buffer, drv_info->rx_buffer, sizeof(*buffer) * count); ffa_rx_release(); mutex_unlock(&drv_info->rx_lock); return count; } /* buffer is allocated and caller must free the same if returned count > 0 */ static int ffa_partition_probe(const uuid_t *uuid, struct ffa_partition_info **buffer) { int count; u32 uuid0_4[4]; struct ffa_partition_info *pbuf; export_uuid((u8 *)uuid0_4, uuid); count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2], uuid0_4[3], NULL, 0); if (count <= 0) return count; pbuf = kcalloc(count, sizeof(*pbuf), GFP_KERNEL); if (!pbuf) return -ENOMEM; count = __ffa_partition_info_get(uuid0_4[0], uuid0_4[1], uuid0_4[2], uuid0_4[3], pbuf, count); if (count <= 0) kfree(pbuf); else *buffer = pbuf; return count; } #define VM_ID_MASK GENMASK(15, 0) static int ffa_id_get(u16 *vm_id) { ffa_value_t id; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_ID_GET, }, &id); if (id.a0 == FFA_ERROR) return ffa_to_linux_errno((int)id.a2); *vm_id = FIELD_GET(VM_ID_MASK, (id.a2)); return 0; } static int ffa_msg_send_direct_req(u16 src_id, u16 dst_id, bool mode_32bit, struct ffa_send_direct_data *data) { u32 req_id, resp_id, src_dst_ids = PACK_TARGET_INFO(src_id, dst_id); ffa_value_t ret; if (mode_32bit) { req_id = FFA_MSG_SEND_DIRECT_REQ; resp_id = FFA_MSG_SEND_DIRECT_RESP; } else { req_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_REQ); resp_id = FFA_FN_NATIVE(MSG_SEND_DIRECT_RESP); } invoke_ffa_fn((ffa_value_t){ .a0 = req_id, .a1 = src_dst_ids, .a2 = 0, .a3 = data->data0, .a4 = data->data1, .a5 = data->data2, .a6 = data->data3, .a7 = data->data4, }, &ret); while (ret.a0 == FFA_INTERRUPT) invoke_ffa_fn((ffa_value_t){ .a0 = FFA_RUN, .a1 = ret.a1, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); if (ret.a0 == resp_id) { data->data0 = ret.a3; data->data1 = ret.a4; data->data2 = ret.a5; data->data3 = ret.a6; data->data4 = ret.a7; return 0; } return -EINVAL; } static int ffa_mem_first_frag(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len, u32 len, u64 *handle) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = func_id, .a1 = len, .a2 = frag_len, .a3 = buf, .a4 = buf_sz, }, &ret); while (ret.a0 == FFA_MEM_OP_PAUSE) invoke_ffa_fn((ffa_value_t){ .a0 = FFA_MEM_OP_RESUME, .a1 = ret.a1, .a2 = ret.a2, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); if (ret.a0 != FFA_SUCCESS) return -EOPNOTSUPP; if (handle) *handle = PACK_HANDLE(ret.a2, ret.a3); return frag_len; } static int ffa_mem_next_frag(u64 handle, u32 frag_len) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_MEM_FRAG_TX, .a1 = HANDLE_LOW(handle), .a2 = HANDLE_HIGH(handle), .a3 = frag_len, }, &ret); while (ret.a0 == FFA_MEM_OP_PAUSE) invoke_ffa_fn((ffa_value_t){ .a0 = FFA_MEM_OP_RESUME, .a1 = ret.a1, .a2 = ret.a2, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); if (ret.a0 != FFA_MEM_FRAG_RX) return -EOPNOTSUPP; return ret.a3; } static int ffa_transmit_fragment(u32 func_id, phys_addr_t buf, u32 buf_sz, u32 frag_len, u32 len, u64 *handle, bool first) { if (!first) return ffa_mem_next_frag(*handle, frag_len); return ffa_mem_first_frag(func_id, buf, buf_sz, frag_len, len, handle); } static u32 ffa_get_num_pages_sg(struct scatterlist *sg) { u32 num_pages = 0; do { num_pages += sg->length / FFA_PAGE_SIZE; } while ((sg = sg_next(sg))); return num_pages; } static int ffa_setup_and_transmit(u32 func_id, void *buffer, u32 max_fragsize, struct ffa_mem_ops_args *args) { int rc = 0; bool first = true; phys_addr_t addr = 0; struct ffa_composite_mem_region *composite; struct ffa_mem_region_addr_range *constituents; struct ffa_mem_region_attributes *ep_mem_access; struct ffa_mem_region *mem_region = buffer; u32 idx, frag_len, length, buf_sz = 0, num_entries = sg_nents(args->sg); mem_region->tag = args->tag; mem_region->flags = args->flags; mem_region->sender_id = drv_info->vm_id; mem_region->attributes = FFA_MEM_NORMAL | FFA_MEM_WRITE_BACK | FFA_MEM_INNER_SHAREABLE; ep_mem_access = &mem_region->ep_mem_access[0]; for (idx = 0; idx < args->nattrs; idx++, ep_mem_access++) { ep_mem_access->receiver = args->attrs[idx].receiver; ep_mem_access->attrs = args->attrs[idx].attrs; ep_mem_access->composite_off = COMPOSITE_OFFSET(args->nattrs); } mem_region->ep_count = args->nattrs; composite = buffer + COMPOSITE_OFFSET(args->nattrs); composite->total_pg_cnt = ffa_get_num_pages_sg(args->sg); composite->addr_range_cnt = num_entries; length = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, num_entries); frag_len = COMPOSITE_CONSTITUENTS_OFFSET(args->nattrs, 0); if (frag_len > max_fragsize) return -ENXIO; if (!args->use_txbuf) { addr = virt_to_phys(buffer); buf_sz = max_fragsize / FFA_PAGE_SIZE; } constituents = buffer + frag_len; idx = 0; do { if (frag_len == max_fragsize) { rc = ffa_transmit_fragment(func_id, addr, buf_sz, frag_len, length, &args->g_handle, first); if (rc < 0) return -ENXIO; first = false; idx = 0; frag_len = 0; constituents = buffer; } if ((void *)constituents - buffer > max_fragsize) { pr_err("Memory Region Fragment > Tx Buffer size\n"); return -EFAULT; } constituents->address = sg_phys(args->sg); constituents->pg_cnt = args->sg->length / FFA_PAGE_SIZE; constituents++; frag_len += sizeof(struct ffa_mem_region_addr_range); } while ((args->sg = sg_next(args->sg))); return ffa_transmit_fragment(func_id, addr, buf_sz, frag_len, length, &args->g_handle, first); } static int ffa_memory_ops(u32 func_id, struct ffa_mem_ops_args *args) { int ret; void *buffer; if (!args->use_txbuf) { buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); if (!buffer) return -ENOMEM; } else { buffer = drv_info->tx_buffer; mutex_lock(&drv_info->tx_lock); } ret = ffa_setup_and_transmit(func_id, buffer, RXTX_BUFFER_SIZE, args); if (args->use_txbuf) mutex_unlock(&drv_info->tx_lock); else free_pages_exact(buffer, RXTX_BUFFER_SIZE); return ret < 0 ? ret : 0; } static int ffa_memory_reclaim(u64 g_handle, u32 flags) { ffa_value_t ret; invoke_ffa_fn((ffa_value_t){ .a0 = FFA_MEM_RECLAIM, .a1 = HANDLE_LOW(g_handle), .a2 = HANDLE_HIGH(g_handle), .a3 = flags, }, &ret); if (ret.a0 == FFA_ERROR) return ffa_to_linux_errno((int)ret.a2); return 0; } static u32 ffa_api_version_get(void) { return drv_info->version; } static int ffa_partition_info_get(const char *uuid_str, struct ffa_partition_info *buffer) { int count; uuid_t uuid; struct ffa_partition_info *pbuf; if (uuid_parse(uuid_str, &uuid)) { pr_err("invalid uuid (%s)\n", uuid_str); return -ENODEV; } count = ffa_partition_probe(&uuid, &pbuf); if (count <= 0) return -ENOENT; memcpy(buffer, pbuf, sizeof(*pbuf) * count); kfree(pbuf); return 0; } static void ffa_mode_32bit_set(struct ffa_device *dev) { dev->mode_32bit = true; } static int ffa_sync_send_receive(struct ffa_device *dev, struct ffa_send_direct_data *data) { return ffa_msg_send_direct_req(drv_info->vm_id, dev->vm_id, dev->mode_32bit, data); } static int ffa_memory_share(struct ffa_device *dev, struct ffa_mem_ops_args *args) { if (dev->mode_32bit) return ffa_memory_ops(FFA_MEM_SHARE, args); return ffa_memory_ops(FFA_FN_NATIVE(MEM_SHARE), args); } static int ffa_memory_lend(struct ffa_device *dev, struct ffa_mem_ops_args *args) { /* Note that upon a successful MEM_LEND request the caller * must ensure that the memory region specified is not accessed * until a successful MEM_RECALIM call has been made. * On systems with a hypervisor present this will been enforced, * however on systems without a hypervisor the responsibility * falls to the calling kernel driver to prevent access. */ if (dev->mode_32bit) return ffa_memory_ops(FFA_MEM_LEND, args); return ffa_memory_ops(FFA_FN_NATIVE(MEM_LEND), args); } static const struct ffa_dev_ops ffa_ops = { .api_version_get = ffa_api_version_get, .partition_info_get = ffa_partition_info_get, .mode_32bit_set = ffa_mode_32bit_set, .sync_send_receive = ffa_sync_send_receive, .memory_reclaim = ffa_memory_reclaim, .memory_share = ffa_memory_share, .memory_lend = ffa_memory_lend, }; const struct ffa_dev_ops *ffa_dev_ops_get(struct ffa_device *dev) { if (ffa_device_is_valid(dev)) return &ffa_ops; return NULL; } EXPORT_SYMBOL_GPL(ffa_dev_ops_get); void ffa_device_match_uuid(struct ffa_device *ffa_dev, const uuid_t *uuid) { int count, idx; struct ffa_partition_info *pbuf, *tpbuf; count = ffa_partition_probe(uuid, &pbuf); if (count <= 0) return; for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) if (tpbuf->id == ffa_dev->vm_id) uuid_copy(&ffa_dev->uuid, uuid); kfree(pbuf); } static void ffa_setup_partitions(void) { int count, idx; struct ffa_device *ffa_dev; struct ffa_partition_info *pbuf, *tpbuf; count = ffa_partition_probe(&uuid_null, &pbuf); if (count <= 0) { pr_info("%s: No partitions found, error %d\n", __func__, count); return; } for (idx = 0, tpbuf = pbuf; idx < count; idx++, tpbuf++) { /* Note that the &uuid_null parameter will require * ffa_device_match() to find the UUID of this partition id * with help of ffa_device_match_uuid(). Once the FF-A spec * is updated to provide correct UUID here for each partition * as part of the discovery API, we need to pass the * discovered UUID here instead. */ ffa_dev = ffa_device_register(&uuid_null, tpbuf->id); if (!ffa_dev) { pr_err("%s: failed to register partition ID 0x%x\n", __func__, tpbuf->id); continue; } } kfree(pbuf); } static int __init ffa_init(void) { int ret; ret = ffa_transport_init(&invoke_ffa_fn); if (ret) return ret; ret = arm_ffa_bus_init(); if (ret) return ret; drv_info = kzalloc(sizeof(*drv_info), GFP_KERNEL); if (!drv_info) { ret = -ENOMEM; goto ffa_bus_exit; } ret = ffa_version_check(&drv_info->version); if (ret) goto free_drv_info; if (ffa_id_get(&drv_info->vm_id)) { pr_err("failed to obtain VM id for self\n"); ret = -ENODEV; goto free_drv_info; } drv_info->rx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); if (!drv_info->rx_buffer) { ret = -ENOMEM; goto free_pages; } drv_info->tx_buffer = alloc_pages_exact(RXTX_BUFFER_SIZE, GFP_KERNEL); if (!drv_info->tx_buffer) { ret = -ENOMEM; goto free_pages; } ret = ffa_rxtx_map(virt_to_phys(drv_info->tx_buffer), virt_to_phys(drv_info->rx_buffer), RXTX_BUFFER_SIZE / FFA_PAGE_SIZE); if (ret) { pr_err("failed to register FFA RxTx buffers\n"); goto free_pages; } mutex_init(&drv_info->rx_lock); mutex_init(&drv_info->tx_lock); ffa_setup_partitions(); return 0; free_pages: if (drv_info->tx_buffer) free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE); free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE); free_drv_info: kfree(drv_info); ffa_bus_exit: arm_ffa_bus_exit(); return ret; } subsys_initcall(ffa_init); static void __exit ffa_exit(void) { ffa_rxtx_unmap(drv_info->vm_id); free_pages_exact(drv_info->tx_buffer, RXTX_BUFFER_SIZE); free_pages_exact(drv_info->rx_buffer, RXTX_BUFFER_SIZE); kfree(drv_info); arm_ffa_bus_exit(); } module_exit(ffa_exit); MODULE_ALIAS("arm-ffa"); MODULE_AUTHOR("Sudeep Holla "); MODULE_DESCRIPTION("Arm FF-A interface driver"); MODULE_LICENSE("GPL v2");