| From b3c7d84dcde6ee1cbc13e10664d24ffa220f5fb3 Mon Sep 17 00:00:00 2001 |
| From: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com> |
| Date: Mon, 15 Aug 2022 15:12:49 +0100 |
| Subject: [PATCH 14/26] arm_ffa: introduce FF-A MM communication |
| |
| Add MM communication support using FF-A transport |
| |
| Access an SP's service through EFI MM communication protocol. |
| |
| This feature allows accessing MM partitions services through |
| EFI MM communication protocol. MM partitions such as StandAlonneMM |
| or smm-gateway secure partitions which reside in secure world. |
| |
| An MM shared buffer and a door bell event are used to exchange |
| the data. |
| |
| The data is used by EFI services such as GetVariable()/SetVariable() |
| and copied from the communication buffer to the MM shared buffer. |
| |
| The secure partition is notified about availability of data in the |
| MM shared buffer by an FF-A message (door bell). |
| |
| On such event, MM SP can read the data and updates the MM shared |
| buffer with the response data. |
| |
| The response data is copied back to the communication buffer and |
| consumed by the EFI subsystem. |
| |
| FF-A driver private data is copied to EFI runtime section at |
| ExitBootServices(). This garantees secure world partitions data are |
| available at EFI runtime level. |
| |
| Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com> |
| Signed-off-by: Gowtham Suresh Kumar <gowtham.sureshkumar@arm.com> |
| Upstream-Status: Submitted [cover letter: https://lore.kernel.org/all/20220926101723.9965-1-abdellatif.elkhlifi@arm.com/] |
| --- |
| |
| Changelog: |
| =============== |
| |
| v4: |
| |
| * use the new FF-A driver interfaces |
| * discover MM partitions at runtime |
| * copy FF-A driver private data to EFI runtime section at |
| ExitBootServices() |
| * drop use of FFA_ERR_STAT_SUCCESS error code |
| * replace EFI_BUFFER_TOO_SMALL by EFI_OUT_OF_RESOURCES |
| in ffa_mm_communicate(). No need for efi_memcpy_runtime() anymore |
| * revert the error log in mm_communicate() in case of failure |
| * remove packed attribute from efi_mm_communicate_header and |
| smm_variable_communicate_header |
| |
| v2: |
| |
| * set default values to 0 for FFA_SHARED_MM_BUFFER_SIZE, FFA_SHARED_MM_BUFFER_ADDR and MM_SP_UUID_DATA and add warnings |
| |
| v1: |
| |
| * introduce FF-A MM communication |
| |
| arch/arm/cpu/armv8/cache.S | 16 ++ |
| arch/arm/cpu/armv8/cache_v8.c | 3 +- |
| include/mm_communication.h | 7 +- |
| lib/efi_loader/Kconfig | 14 +- |
| lib/efi_loader/efi_boottime.c | 7 + |
| lib/efi_loader/efi_variable_tee.c | 261 +++++++++++++++++++++++++++++- |
| 6 files changed, 299 insertions(+), 9 deletions(-) |
| |
| diff --git a/arch/arm/cpu/armv8/cache.S b/arch/arm/cpu/armv8/cache.S |
| index d1cee23437..f69ef64ed6 100644 |
| --- a/arch/arm/cpu/armv8/cache.S |
| +++ b/arch/arm/cpu/armv8/cache.S |
| @@ -21,7 +21,11 @@ |
| * x1: 0 clean & invalidate, 1 invalidate only |
| * x2~x9: clobbered |
| */ |
| +#ifdef CONFIG_EFI_LOADER |
| +.pushsection .text.efi_runtime, "ax" |
| +#else |
| .pushsection .text.__asm_dcache_level, "ax" |
| +#endif |
| ENTRY(__asm_dcache_level) |
| lsl x12, x0, #1 |
| msr csselr_el1, x12 /* select cache level */ |
| @@ -65,7 +69,11 @@ ENDPROC(__asm_dcache_level) |
| * |
| * flush or invalidate all data cache by SET/WAY. |
| */ |
| +#ifdef CONFIG_EFI_LOADER |
| +.pushsection .text.efi_runtime, "ax" |
| +#else |
| .pushsection .text.__asm_dcache_all, "ax" |
| +#endif |
| ENTRY(__asm_dcache_all) |
| mov x1, x0 |
| dsb sy |
| @@ -109,7 +117,11 @@ ENTRY(__asm_flush_dcache_all) |
| ENDPROC(__asm_flush_dcache_all) |
| .popsection |
| |
| +#ifdef CONFIG_EFI_LOADER |
| +.pushsection .text.efi_runtime, "ax" |
| +#else |
| .pushsection .text.__asm_invalidate_dcache_all, "ax" |
| +#endif |
| ENTRY(__asm_invalidate_dcache_all) |
| mov x0, #0x1 |
| b __asm_dcache_all |
| @@ -182,7 +194,11 @@ ENTRY(__asm_invalidate_icache_all) |
| ENDPROC(__asm_invalidate_icache_all) |
| .popsection |
| |
| +#ifdef CONFIG_EFI_LOADER |
| +.pushsection .text.efi_runtime, "ax" |
| +#else |
| .pushsection .text.__asm_invalidate_l3_dcache, "ax" |
| +#endif |
| WEAK(__asm_invalidate_l3_dcache) |
| mov x0, #0 /* return status as success */ |
| ret |
| diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c |
| index e4736e5643..afbc487fa1 100644 |
| --- a/arch/arm/cpu/armv8/cache_v8.c |
| +++ b/arch/arm/cpu/armv8/cache_v8.c |
| @@ -9,6 +9,7 @@ |
| |
| #include <common.h> |
| #include <cpu_func.h> |
| +#include <efi_loader.h> |
| #include <hang.h> |
| #include <log.h> |
| #include <asm/cache.h> |
| @@ -445,7 +446,7 @@ __weak void mmu_setup(void) |
| /* |
| * Performs a invalidation of the entire data cache at all levels |
| */ |
| -void invalidate_dcache_all(void) |
| +void __efi_runtime invalidate_dcache_all(void) |
| { |
| __asm_invalidate_dcache_all(); |
| __asm_invalidate_l3_dcache(); |
| diff --git a/include/mm_communication.h b/include/mm_communication.h |
| index e65fbde60d..32dc5dbac8 100644 |
| --- a/include/mm_communication.h |
| +++ b/include/mm_communication.h |
| @@ -13,6 +13,9 @@ |
| |
| #include <part_efi.h> |
| |
| +/* MM service UUID string (big-endian format). This UUID is common across all MM SPs */ |
| +#define MM_SP_UUID "33d532ed-e699-0942-c09c-a798d9cd722d" |
| + |
| /* |
| * Interface to the pseudo Trusted Application (TA), which provides a |
| * communication channel with the Standalone MM (Management Mode) |
| @@ -43,7 +46,7 @@ |
| * To avoid confusion in interpreting frames, the communication buffer should |
| * always begin with efi_mm_communicate_header. |
| */ |
| -struct __packed efi_mm_communicate_header { |
| +struct efi_mm_communicate_header { |
| efi_guid_t header_guid; |
| size_t message_len; |
| u8 data[]; |
| @@ -145,7 +148,7 @@ struct smm_variable_communicate_header { |
| * Defined in EDK2 as SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE. |
| * |
| */ |
| -struct smm_variable_access { |
| +struct __packed smm_variable_access { |
| efi_guid_t guid; |
| efi_uintn_t data_size; |
| efi_uintn_t name_size; |
| diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig |
| index e3f2402d0e..2a6d70f862 100644 |
| --- a/lib/efi_loader/Kconfig |
| +++ b/lib/efi_loader/Kconfig |
| @@ -60,13 +60,23 @@ config EFI_VARIABLE_FILE_STORE |
| stored as file /ubootefi.var on the EFI system partition. |
| |
| config EFI_MM_COMM_TEE |
| - bool "UEFI variables storage service via OP-TEE" |
| - depends on OPTEE |
| + bool "UEFI variables storage service via the trusted world" |
| + depends on OPTEE || ARM_FFA_TRANSPORT |
| help |
| + Allowing access to the MM SP services (SPs such as StandAlonneMM, smm-gateway). |
| + When using the u-boot OP-TEE driver, StandAlonneMM is supported. |
| + When using the u-boot FF-A driver any MM SP is supported. |
| + |
| If OP-TEE is present and running StandAloneMM, dispatch all UEFI |
| variable related operations to that. The application will verify, |
| authenticate and store the variables on an RPMB. |
| |
| + When ARM_FFA_TRANSPORT is used, dispatch all UEFI variable related |
| + operations to the MM SP running in the secure world. |
| + A door bell mechanism is used to notify the SP when there is data in the shared |
| + MM buffer. The data is copied by u-boot to the shared buffer before issuing |
| + the door bell event. |
| + |
| config EFI_VARIABLE_NO_STORE |
| bool "Don't persist non-volatile UEFI variables" |
| help |
| diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c |
| index 8fa9a58d76..cede7826bd 100644 |
| --- a/lib/efi_loader/efi_boottime.c |
| +++ b/lib/efi_loader/efi_boottime.c |
| @@ -2185,6 +2185,13 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle, |
| debug("[efi_boottime][INFO]: FF-A RX/TX buffers unmapped\n"); |
| #endif |
| |
| +#if CONFIG_IS_ENABLED(ARM_FFA_EFI_RUNTIME_MODE) && !CONFIG_IS_ENABLED(SANDBOX_FFA) |
| + if (ffa_copy_runtime_data()) |
| + printf("ERROR: EFI: FFA: copying runtime data\n"); |
| + else |
| + printf("INFO: EFI: FFA: runtime data copied\n"); |
| +#endif |
| + |
| /* Patch out unsupported runtime function */ |
| efi_runtime_detach(); |
| |
| diff --git a/lib/efi_loader/efi_variable_tee.c b/lib/efi_loader/efi_variable_tee.c |
| index dfef18435d..7d9d577281 100644 |
| --- a/lib/efi_loader/efi_variable_tee.c |
| +++ b/lib/efi_loader/efi_variable_tee.c |
| @@ -15,6 +15,36 @@ |
| #include <malloc.h> |
| #include <mm_communication.h> |
| |
| +#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) |
| + |
| +#include <arm_ffa.h> |
| +#include <cpu_func.h> |
| +#include <mapmem.h> |
| + |
| +#ifndef FFA_SHARED_MM_BUFFER_SIZE |
| +#warning "FFA_SHARED_MM_BUFFER_SIZE must be defined in include/configs/<board>.h" |
| +#define FFA_SHARED_MM_BUFFER_SIZE 0 |
| +#endif |
| + |
| +#ifndef FFA_SHARED_MM_BUFFER_OFFSET |
| +#warning "FFA_SHARED_MM_BUFFER_OFFSET must be defined in include/configs/<board>.h" |
| +#define FFA_SHARED_MM_BUFFER_OFFSET 0 |
| +#endif |
| + |
| +#ifndef FFA_SHARED_MM_BUFFER_ADDR |
| +#warning "FFA_SHARED_MM_BUFFER_ADDR must be defined in include/configs/<board>.h" |
| +#define FFA_SHARED_MM_BUFFER_ADDR 0 |
| +#endif |
| + |
| +/* MM return codes */ |
| +#define MM_SUCCESS (0) |
| + |
| +const char *mm_sp_svc_uuid = MM_SP_UUID; |
| + |
| +static __efi_runtime_data u16 mm_sp_id; |
| + |
| +#endif |
| + |
| extern struct efi_var_file __efi_runtime_data *efi_var_buf; |
| static efi_uintn_t max_buffer_size; /* comm + var + func + data */ |
| static efi_uintn_t max_payload_size; /* func + data */ |
| @@ -24,6 +54,7 @@ struct mm_connection { |
| u32 session; |
| }; |
| |
| +#if (IS_ENABLED(CONFIG_OPTEE)) |
| /** |
| * get_connection() - Retrieve OP-TEE session for a specific UUID. |
| * |
| @@ -143,16 +174,227 @@ static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize) |
| |
| return ret; |
| } |
| +#endif |
| + |
| +#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) |
| |
| /** |
| - * mm_communicate() - Adjust the cmonnucation buffer to StandAlonneMM and send |
| + * ffa_notify_mm_sp() - Announce there is data in the shared buffer |
| + * |
| + * Notifies the MM partition in the trusted world that |
| + * data is available in the shared buffer. |
| + * This is a blocking call during which trusted world has exclusive access |
| + * to the MM shared buffer. |
| + * |
| + * Return: |
| + * |
| + * 0 on success |
| + */ |
| +static int __efi_runtime ffa_notify_mm_sp(void) |
| +{ |
| + struct ffa_send_direct_data msg = {0}; |
| + int ret; |
| + int sp_event_ret = -1; |
| + |
| + if (!ffa_bus_ops_get()) |
| + return -EINVAL; |
| + |
| + msg.data0 = FFA_SHARED_MM_BUFFER_OFFSET; /* x3 */ |
| + |
| + ret = ffa_bus_ops_get()->sync_send_receive(mm_sp_id, &msg); |
| + if (ret != 0) |
| + return ret; |
| + |
| + sp_event_ret = msg.data0; /* x3 */ |
| + |
| + if (sp_event_ret == MM_SUCCESS) |
| + return 0; |
| + |
| + /* |
| + * Failure to notify the MM SP |
| + */ |
| + |
| + return -EACCES; |
| +} |
| + |
| +/** |
| + * ffa_discover_mm_sp_id() - Query the MM partition ID |
| + * |
| + * Use the FF-A driver to get the MM partition ID. |
| + * If multiple partitions are found, use the first one. |
| + * This is a boot time function. |
| + * |
| + * Return: |
| + * |
| + * 0 on success |
| + */ |
| +static int ffa_discover_mm_sp_id(void) |
| +{ |
| + u32 count = 0, size = 0; |
| + int ret; |
| + struct ffa_partition_info *parts_info; |
| + |
| + if (!ffa_bus_ops_get()) |
| + return -EINVAL; |
| + |
| + /* |
| + * get from the driver the count of the SPs matching the UUID |
| + */ |
| + ret = ffa_bus_ops_get()->partition_info_get(mm_sp_svc_uuid, &count, NULL); |
| + if (ret != 0) { |
| + log_err("EFI: Failure in querying partitions count (error code: %d)\n", ret); |
| + return ret; |
| + } |
| + |
| + if (!count) { |
| + log_info("EFI: No MM partition found\n"); |
| + return ret; |
| + } |
| + |
| + /* |
| + * pre-allocate a buffer to be filled by the driver |
| + * with ffa_partition_info structs |
| + */ |
| + |
| + log_info("EFI: Pre-allocating %d partition(s) info structures\n", count); |
| + |
| + parts_info = calloc(count, sizeof(struct ffa_partition_info)); |
| + if (!parts_info) |
| + return -EINVAL; |
| + |
| + size = count * sizeof(struct ffa_partition_info); |
| + |
| + /* |
| + * ask the driver to fill the |
| + * buffer with the SPs info |
| + */ |
| + ret = ffa_bus_ops_get()->partition_info_get(mm_sp_svc_uuid, &size, parts_info); |
| + if (ret != 0) { |
| + log_err("EFI: Failure in querying partition(s) info (error code: %d)\n", ret); |
| + free(parts_info); |
| + return ret; |
| + } |
| + |
| + /* |
| + * MM SPs found , use the first one |
| + */ |
| + |
| + mm_sp_id = parts_info[0].id; |
| + |
| + log_info("EFI: MM partition ID 0x%x\n", mm_sp_id); |
| + |
| + free(parts_info); |
| + |
| + return 0; |
| +} |
| + |
| +/** |
| + * ffa_mm_communicate() - Exchange EFI services data with the MM partition using FF-A |
| + * @comm_buf: locally allocated communication buffer used for rx/tx |
| + * @dsize: communication buffer size |
| + * |
| + * Issues a door bell event to notify the MM partition (SP) running in OP-TEE |
| + * that there is data to read from the shared buffer. |
| + * Communication with the MM SP is performed using FF-A transport. |
| + * On the event, MM SP can read the data from the buffer and |
| + * update the MM shared buffer with response data. |
| + * The response data is copied back to the communication buffer. |
| + * |
| + * Return: |
| + * |
| + * EFI status code |
| + */ |
| +static efi_status_t __efi_runtime ffa_mm_communicate(void *comm_buf, ulong comm_buf_size) |
| +{ |
| + ulong tx_data_size; |
| + int ffa_ret; |
| + struct efi_mm_communicate_header *mm_hdr; |
| + void *virt_shared_buf; |
| + |
| + if (!comm_buf) |
| + return EFI_INVALID_PARAMETER; |
| + |
| + /* Discover MM partition ID at boot time */ |
| + if (!mm_sp_id && ffa_discover_mm_sp_id() != 0) { |
| + log_err("EFI: Failure to discover MM partition ID at boot time\n"); |
| + return EFI_UNSUPPORTED; |
| + } |
| + |
| + mm_hdr = (struct efi_mm_communicate_header *)comm_buf; |
| + tx_data_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t); |
| + |
| + if (comm_buf_size != tx_data_size || tx_data_size > FFA_SHARED_MM_BUFFER_SIZE) |
| + return EFI_INVALID_PARAMETER; |
| + |
| + /* Copy the data to the shared buffer */ |
| + |
| + virt_shared_buf = (void *)map_sysmem((phys_addr_t)FFA_SHARED_MM_BUFFER_ADDR, 0); |
| + efi_memcpy_runtime(virt_shared_buf, comm_buf, tx_data_size); |
| + |
| + /* |
| + * The secure world might have cache disabled for |
| + * the device region used for shared buffer (which is the case for Optee). |
| + * In this case, the secure world reads the data from DRAM. |
| + * Let's flush the cache so the DRAM is updated with the latest data. |
| + */ |
| + #ifdef CONFIG_ARM64 |
| + invalidate_dcache_all(); |
| + #endif |
| + |
| + /* Announce there is data in the shared buffer */ |
| + |
| + ffa_ret = ffa_notify_mm_sp(); |
| + if (ffa_ret) |
| + unmap_sysmem(virt_shared_buf); |
| + |
| + switch (ffa_ret) { |
| + case 0: |
| + { |
| + ulong rx_data_size; |
| + /* Copy the MM SP response from the shared buffer to the communication buffer */ |
| + rx_data_size = ((struct efi_mm_communicate_header *)virt_shared_buf)->message_len + |
| + sizeof(efi_guid_t) + |
| + sizeof(size_t); |
| + |
| + if (rx_data_size > comm_buf_size) { |
| + unmap_sysmem(virt_shared_buf); |
| + return EFI_OUT_OF_RESOURCES; |
| + } |
| + |
| + efi_memcpy_runtime(comm_buf, virt_shared_buf, rx_data_size); |
| + unmap_sysmem(virt_shared_buf); |
| + |
| + return EFI_SUCCESS; |
| + } |
| + case -EINVAL: |
| + return EFI_DEVICE_ERROR; |
| + case -EPERM: |
| + return EFI_INVALID_PARAMETER; |
| + case -EACCES: |
| + return EFI_ACCESS_DENIED; |
| + case -EBUSY: |
| + return EFI_OUT_OF_RESOURCES; |
| + default: |
| + return EFI_ACCESS_DENIED; |
| + } |
| +} |
| +#endif |
| + |
| +/** |
| + * mm_communicate() - Adjust the communication buffer to the MM SP and send |
| * it to OP-TEE |
| * |
| - * @comm_buf: locally allocted communcation buffer |
| + * @comm_buf: locally allocated communication buffer |
| * @dsize: buffer size |
| + * |
| + * The MM SP (also called partition) can be StandAlonneMM or smm-gateway. |
| + * The comm_buf format is the same for both partitions. |
| + * When using the u-boot OP-TEE driver, StandAlonneMM is supported. |
| + * When using the u-boot FF-A driver, StandAlonneMM and smm-gateway are supported. |
| + * |
| * Return: status code |
| */ |
| -static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize) |
| +static efi_status_t __efi_runtime mm_communicate(u8 *comm_buf, efi_uintn_t dsize) |
| { |
| efi_status_t ret; |
| struct efi_mm_communicate_header *mm_hdr; |
| @@ -162,7 +404,11 @@ static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize) |
| mm_hdr = (struct efi_mm_communicate_header *)comm_buf; |
| var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data; |
| |
| + #if (IS_ENABLED(CONFIG_OPTEE)) |
| ret = optee_mm_communicate(comm_buf, dsize); |
| + #elif (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) |
| + ret = ffa_mm_communicate(comm_buf, dsize); |
| + #endif |
| if (ret != EFI_SUCCESS) { |
| log_err("%s failed!\n", __func__); |
| return ret; |
| @@ -258,6 +504,13 @@ efi_status_t EFIAPI get_max_payload(efi_uintn_t *size) |
| goto out; |
| } |
| *size = var_payload->size; |
| + |
| + #if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) |
| + if (*size > FFA_SHARED_MM_BUFFER_SIZE) |
| + *size = FFA_SHARED_MM_BUFFER_SIZE - MM_COMMUNICATE_HEADER_SIZE - |
| + MM_VARIABLE_COMMUNICATE_SIZE; |
| + #endif |
| + |
| /* |
| * There seems to be a bug in EDK2 miscalculating the boundaries and |
| * size checks, so deduct 2 more bytes to fulfill this requirement. Fix |
| @@ -697,7 +950,7 @@ void efi_variables_boot_exit_notify(void) |
| ret = EFI_NOT_FOUND; |
| |
| if (ret != EFI_SUCCESS) |
| - log_err("Unable to notify StMM for ExitBootServices\n"); |
| + log_err("Unable to notify the MM partition for ExitBootServices\n"); |
| free(comm_buf); |
| |
| /* |
| -- |
| 2.17.1 |
| |