Hi Abdellatif, On Wed, 12 Apr 2023 at 03:43, Abdellatif El Khlifi <abdellatif.elkhl...@arm.com> wrote: > > Add MM communication support using FF-A transport > > 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. > > MM communication protocol supports FF-A 64-bit direct messaging. > > Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhl...@arm.com> > Signed-off-by: Gowtham Suresh Kumar <gowtham.sureshku...@arm.com> > Cc: Tom Rini <tr...@konsulko.com> > Cc: Simon Glass <s...@chromium.org> > Cc: Ilias Apalodimas <ilias.apalodi...@linaro.org> > Cc: Jens Wiklander <jens.wiklan...@linaro.org> > > --- > Changelog: > =============== > > v11: > > * rename select_ffa_mm_comms() to select_mm_comms() > * improve the logic of MM transport selection in mm_communicate() > * addressing nits > > v10: > > * use the FF-A driver Uclass operations > * use uclass_first_device() > * addressing nits > > v9: align how FF-A is used with FF-A discovery through DM > > v8: > > * isolate the compilation choices between FF-A and OP-TEE > * update partition_info_get() second argument to be an SP count > * pass NULL device pointer to the FF-A bus discovery and operations > > v7: > > * set the MM door bell event to use 64-bit direct messaging > * issue a compile time error when one of these macros are not found : > FFA_SHARED_MM_BUFFER_SIZE, FFA_SHARED_MM_BUFFER_OFFSET, > FFA_SHARED_MM_BUFFER_ADDR > * make mm_sp_svc_uuid static > * replace EINVAL with ENOMEM in ffa_discover_mm_sp_id() when calloc() fails > * improve use of unmap_sysmem() in ffa_mm_communicate() > > v6: > > * add FF-A runtime discovery at MM communication level > * drop EFI runtime support for FF-A MM communication > * revert the changes in include/mm_communication.h for > efi_mm_communicate_header and smm_variable_access structures > > 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 with 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 > > include/mm_communication.h | 13 ++ > lib/efi_loader/Kconfig | 14 +- > lib/efi_loader/efi_variable_tee.c | 312 +++++++++++++++++++++++++++++- > 3 files changed, 333 insertions(+), 6 deletions(-) > > diff --git a/include/mm_communication.h b/include/mm_communication.h > index e65fbde60d..f17847583b 100644 > --- a/include/mm_communication.h > +++ b/include/mm_communication.h > @@ -6,6 +6,9 @@ > * Copyright (c) 2017, Intel Corporation. All rights reserved. > * Copyright (C) 2020 Linaro Ltd. <sughosh.g...@linaro.org> > * Copyright (C) 2020 Linaro Ltd. <ilias.apalodi...@linaro.org> > + * Copyright 2022-2023 Arm Limited and/or its affiliates > <open-source-off...@arm.com> > + * Authors: > + * Abdellatif El Khlifi <abdellatif.elkhl...@arm.com> > */ > > #ifndef _MM_COMMUNICATION_H_ > @@ -13,6 +16,9 @@ > > #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) > @@ -248,4 +254,11 @@ struct smm_variable_var_check_property { > u16 name[]; > }; > > +/* supported MM transports */ > +enum mm_comms_select { > + MM_COMMS_UNDEFINED, > + MM_COMMS_FFA, > + MM_COMMS_OPTEE > +}; > + > #endif /* _MM_COMMUNICATION_H_ */ > diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig > index c5835e6ef6..08a6b84101 100644 > --- a/lib/efi_loader/Kconfig > +++ b/lib/efi_loader/Kconfig > @@ -55,13 +55,23 @@ 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_variable_tee.c > b/lib/efi_loader/efi_variable_tee.c > index dfef18435d..a6ec126db5 100644 > --- a/lib/efi_loader/efi_variable_tee.c > +++ b/lib/efi_loader/efi_variable_tee.c > @@ -4,9 +4,14 @@ > * > * Copyright (C) 2019 Linaro Ltd. <sughosh.g...@linaro.org> > * Copyright (C) 2019 Linaro Ltd. <ilias.apalodi...@linaro.org> > + * Copyright 2022-2023 Arm Limited and/or its affiliates > <open-source-off...@arm.com> > + * > + * Authors: > + * Abdellatif El Khlifi <abdellatif.elkhl...@arm.com> > */ > > #include <common.h> > +#include <dm.h> > #include <efi.h> > #include <efi_api.h> > #include <efi_loader.h> > @@ -15,6 +20,36 @@ > #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 > +#error "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 > +#error "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 > +#error "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) > + > +static const char *mm_sp_svc_uuid = MM_SP_UUID; > + > +static 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 +59,7 @@ struct mm_connection { > u32 session; > }; > > +#if (IS_ENABLED(CONFIG_OPTEE)) > /** > * get_connection() - Retrieve OP-TEE session for a specific UUID. > * > @@ -60,6 +96,7 @@ static int get_connection(struct mm_connection *conn) > out: > return rc; > } > +#endif > > /** > * optee_mm_communicate() - Pass a buffer to StandaloneMM running in OP-TEE > @@ -70,6 +107,7 @@ out: > */ > static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize) > { > +#if (IS_ENABLED(CONFIG_OPTEE)) > ulong buf_size; > efi_status_t ret; > struct efi_mm_communicate_header *mm_hdr; > @@ -142,19 +180,269 @@ static efi_status_t optee_mm_communicate(void > *comm_buf, ulong dsize) > } > > return ret; > +#else > + log_err("EFI: Please enable CONFIG_OPTEE for MM comms\n"); > + return EFI_UNSUPPORTED; > +#endif > +} > + > +#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT))
drop extra brackets > + > +/** > + * ffa_notify_mm_sp() - Announce there is data in the shared buffer > + * > + * Notify 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 ffa_notify_mm_sp(void) > +{ > + struct ffa_send_direct_data msg = {0}; > + int ret; > + int sp_event_ret = -1; > + struct udevice *dev; > + > + ret = uclass_first_device_err(UCLASS_FFA, &dev); > + if (ret) { > + log_err("EFI: Cannot find FF-A bus device, notify MM SP > failure\n"); > + return -ENODEV; return ret > + } > + > + msg.data0 = FFA_SHARED_MM_BUFFER_OFFSET; /* x3 */ > + > + ret = ffa_sync_send_receive(dev, mm_sp_id, &msg, 1); > + if (ret) > + 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; > + int ret; > + struct ffa_partition_info *parts_info; > + struct udevice *dev; > + > + ret = uclass_first_device_err(UCLASS_FFA, &dev); > + if (ret) { > + log_err("EFI: Cannot find FF-A bus device, MM SP discovery > failure\n"); > + return -ENODEV; return ret Please check that you don't change error returns unless you really want to, as it makes it hard to debug failures. > + } > + > + /* Get from the driver the count of the SPs matching the UUID */ > + ret = ffa_partition_info_get(dev, mm_sp_svc_uuid, &count, NULL); > + if (ret) { > + log_err("EFI: Failure in querying SPs count (%d), MM SP > discovery failure\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(*parts_info)); Use a local var and drop the calloc() > + if (!parts_info) > + return -ENOMEM; > + > + /* Ask the driver to fill the buffer with the SPs info */ > + ret = ffa_partition_info_get(dev, mm_sp_svc_uuid, &count, parts_info); > + if (ret) { > + log_err("EFI: Failure in querying SPs info (%d), MM SP > discovery failure\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; > +} > +#endif > + > +/** > + * 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 > + * > + * Issue 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 ffa_mm_communicate(void *comm_buf, ulong comm_buf_size) > +{ > +#if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) Please use if() if you can? > + ulong tx_data_size; > + int ffa_ret; > + efi_status_t efi_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()) { > + log_err("EFI: Failure to discover MM SP ID at boot time, FF-A > MM comms failure\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 = map_sysmem((phys_addr_t)FFA_SHARED_MM_BUFFER_ADDR, > 0); > + memcpy(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(); > + > + 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) { > + efi_ret = EFI_OUT_OF_RESOURCES; > + break; > + } > + > + memcpy(comm_buf, virt_shared_buf, rx_data_size); > + efi_ret = EFI_SUCCESS; > + break; > + } > + case -EINVAL: > + efi_ret = EFI_DEVICE_ERROR; > + break; > + case -EPERM: > + efi_ret = EFI_INVALID_PARAMETER; > + break; > + case -EACCES: > + efi_ret = EFI_ACCESS_DENIED; > + break; > + case -EBUSY: > + efi_ret = EFI_OUT_OF_RESOURCES; > + break; > + default: > + efi_ret = EFI_ACCESS_DENIED; > + } > + > + unmap_sysmem(virt_shared_buf); > + return efi_ret; > +#else > + log_err("EFI: Please enable CONFIG_ARM_FFA_TRANSPORT for MM comms\n"); > + return EFI_UNSUPPORTED; > +#endif > +} > + > +/** > + * select_mm_comms() - detect the available MM transport > + * > + * If FF-A is compiled in, make sure the FF-A bus is probed successfully > + * which means FF-A communication with secure world works and ready > + * to be used. > + * > + * If FF-A is not detected, check if OPTEE support is compiled in. > + * > + * Return: > + * > + * On success MM_COMMS_FFA or MM_COMMS_OPTEE. Otherwise, MM_COMMS_UNDEFINED > + */ > +static enum mm_comms_select select_mm_comms(void) > +{ > + struct udevice *dev; > + int ret; > + > + if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) { > + ret = uclass_first_device_err(UCLASS_FFA, &dev); > + if (ret) > + log_err("EFI: Cannot find FF-A bus device, cannot > select FF-A comms\n"); > + else > + return MM_COMMS_FFA; > + } > + > + if (IS_ENABLED(CONFIG_OPTEE)) > + return MM_COMMS_OPTEE; > + > + return MM_COMMS_UNDEFINED; > } > > /** > - * mm_communicate() - Adjust the cmonnucation buffer to StandAlonneMM and > send > + * 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 SP (also called partition) can be any MM SP such as 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, any MM SP is supported. > + * > * Return: status code > */ > static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize) > { > efi_status_t ret; > + enum mm_comms_select mm_comms; > struct efi_mm_communicate_header *mm_hdr; > struct smm_variable_communicate_header *var_hdr; > > @@ -162,7 +450,16 @@ 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; > > - ret = optee_mm_communicate(comm_buf, dsize); > + mm_comms = select_mm_comms(); > + if (mm_comms == MM_COMMS_UNDEFINED) { > + ret = EFI_UNSUPPORTED; > + } else { > + if (mm_comms == MM_COMMS_OPTEE) > + ret = optee_mm_communicate(comm_buf, dsize); > + else > + ret = ffa_mm_communicate(comm_buf, dsize); > + } > + > if (ret != EFI_SUCCESS) { > log_err("%s failed!\n", __func__); > return ret; > @@ -258,6 +555,13 @@ efi_status_t EFIAPI get_max_payload(efi_uintn_t *size) > goto out; > } > *size = var_payload->size; > + > + #if (IS_ENABLED(CONFIG_ARM_FFA_TRANSPORT)) Can this use if () ? > + 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 +1001,7 @@ 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); > > /* > -- > 2.25.1 > Regards, Simon