blob: ae71c1df54c48168b3de78db2583bc170ee46ca1 [file] [log] [blame]
/*
* Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <arch_helpers.h>
#include <assert.h>
#include <bl31.h>
#include <context_mgmt.h>
#include <debug.h>
#include <errno.h>
#include <platform.h>
#include <runtime_svc.h>
#include <secure_partition.h>
#include <smcc.h>
#include <smcc_helpers.h>
#include <spinlock.h>
#include <spm_svc.h>
#include <utils.h>
#include <xlat_tables_v2.h>
#include "spm_private.h"
/* Lock used for SP_MEMORY_ATTRIBUTES_GET and SP_MEMORY_ATTRIBUTES_SET */
static spinlock_t mem_attr_smc_lock;
/*******************************************************************************
* Secure Partition context information.
******************************************************************************/
static secure_partition_context_t sp_ctx;
unsigned int sp_init_in_progress;
/*******************************************************************************
* Replace the S-EL1 re-entry information with S-EL0 re-entry
* information
******************************************************************************/
void spm_setup_next_eret_into_sel0(cpu_context_t *secure_context)
{
assert(secure_context == cm_get_context(SECURE));
cm_set_elr_spsr_el3(SECURE, read_elr_el1(), read_spsr_el1());
}
/*******************************************************************************
* This function takes an SP context pointer and:
* 1. Applies the S-EL1 system register context from sp_ctx->cpu_ctx.
* 2. Saves the current C runtime state (callee-saved registers) on the stack
* frame and saves a reference to this state.
* 3. Calls el3_exit() so that the EL3 system and general purpose registers
* from the sp_ctx->cpu_ctx are used to enter the secure partition image.
******************************************************************************/
static uint64_t spm_synchronous_sp_entry(secure_partition_context_t *sp_ctx_ptr)
{
uint64_t rc;
assert(sp_ctx_ptr != NULL);
assert(sp_ctx_ptr->c_rt_ctx == 0);
assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);
/* Apply the Secure EL1 system register context and switch to it */
cm_el1_sysregs_context_restore(SECURE);
cm_set_next_eret_context(SECURE);
VERBOSE("%s: We're about to enter the Secure partition...\n", __func__);
rc = spm_secure_partition_enter(&sp_ctx_ptr->c_rt_ctx);
#if ENABLE_ASSERTIONS
sp_ctx_ptr->c_rt_ctx = 0;
#endif
return rc;
}
/*******************************************************************************
* This function takes a Secure partition context pointer and:
* 1. Saves the S-EL1 system register context to sp_ctx->cpu_ctx.
* 2. Restores the current C runtime state (callee saved registers) from the
* stack frame using the reference to this state saved in
* spm_secure_partition_enter().
* 3. It does not need to save any general purpose or EL3 system register state
* as the generic smc entry routine should have saved those.
******************************************************************************/
static void __dead2 spm_synchronous_sp_exit(
secure_partition_context_t *sp_ctx_ptr, uint64_t ret)
{
assert(sp_ctx_ptr != NULL);
/* Save the Secure EL1 system register context */
assert(cm_get_context(SECURE) == &sp_ctx_ptr->cpu_ctx);
cm_el1_sysregs_context_save(SECURE);
assert(sp_ctx_ptr->c_rt_ctx != 0);
spm_secure_partition_exit(sp_ctx_ptr->c_rt_ctx, ret);
/* Should never reach here */
assert(0);
}
/*******************************************************************************
* This function passes control to the Secure Partition image (BL32) for the
* first time on the primary cpu after a cold boot. It assumes that a valid
* secure context has already been created by spm_setup() which can be directly
* used. This function performs a synchronous entry into the Secure partition.
* The SP passes control back to this routine through a SMC.
******************************************************************************/
int32_t spm_init(void)
{
entry_point_info_t *secure_partition_ep_info;
uint64_t rc;
VERBOSE("%s entry\n", __func__);
/*
* Get information about the Secure Partition (BL32) image. Its
* absence is a critical failure.
*/
secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
assert(secure_partition_ep_info);
/*
* Initialise the common context and then overlay the S-EL0 specific
* context on top of it.
*/
cm_init_my_context(secure_partition_ep_info);
secure_partition_setup();
/*
* Arrange for an entry into the secure partition.
*/
sp_init_in_progress = 1;
rc = spm_synchronous_sp_entry(&sp_ctx);
assert(rc == 0);
sp_init_in_progress = 0;
VERBOSE("SP_MEMORY_ATTRIBUTES_SET_AARCH64 availability has been revoked\n");
return rc;
}
/*******************************************************************************
* Given a secure partition entrypoint info pointer, entry point PC & pointer to
* a context data structure, this function will initialize the SPM context and
* entry point info for the secure partition.
******************************************************************************/
void spm_init_sp_ep_state(struct entry_point_info *sp_ep_info,
uint64_t pc,
secure_partition_context_t *sp_ctx_ptr)
{
uint32_t ep_attr;
assert(sp_ep_info);
assert(pc);
assert(sp_ctx_ptr);
cm_set_context(&sp_ctx_ptr->cpu_ctx, SECURE);
/* initialise an entrypoint to set up the CPU context */
ep_attr = SECURE | EP_ST_ENABLE;
if (read_sctlr_el3() & SCTLR_EE_BIT)
ep_attr |= EP_EE_BIG;
SET_PARAM_HEAD(sp_ep_info, PARAM_EP, VERSION_1, ep_attr);
sp_ep_info->pc = pc;
/* The secure partition runs in S-EL0. */
sp_ep_info->spsr = SPSR_64(MODE_EL0,
MODE_SP_EL0,
DISABLE_ALL_EXCEPTIONS);
zeromem(&sp_ep_info->args, sizeof(sp_ep_info->args));
}
/*******************************************************************************
* Secure Partition Manager setup. The SPM finds out the SP entrypoint if not
* already known and initialises the context for entry into the SP for its
* initialisation.
******************************************************************************/
int32_t spm_setup(void)
{
entry_point_info_t *secure_partition_ep_info;
VERBOSE("%s entry\n", __func__);
/*
* Get information about the Secure Partition (BL32) image. Its
* absence is a critical failure.
*/
secure_partition_ep_info = bl31_plat_get_next_image_ep_info(SECURE);
if (!secure_partition_ep_info) {
WARN("No SPM provided by BL2 boot loader, Booting device"
" without SPM initialization. SMCs destined for SPM"
" will return SMC_UNK\n");
return 1;
}
/*
* If there's no valid entry point for SP, we return a non-zero value
* signalling failure initializing the service. We bail out without
* registering any handlers
*/
if (!secure_partition_ep_info->pc) {
return 1;
}
spm_init_sp_ep_state(secure_partition_ep_info,
secure_partition_ep_info->pc,
&sp_ctx);
/*
* All SPM initialization done. Now register our init function with
* BL31 for deferred invocation
*/
bl31_register_bl32_init(&spm_init);
VERBOSE("%s exit\n", __func__);
return 0;
}
/*
* Attributes are encoded using a different format in the SMC interface than in
* the Trusted Firmware, where the mmap_attr_t enum type is used. This function
* converts an attributes value from the SMC format to the mmap_attr_t format by
* setting MT_RW/MT_RO, MT_USER/MT_PRIVILEGED and MT_EXECUTE/MT_EXECUTE_NEVER.
* The other fields are left as 0 because they are ignored by the function
* change_mem_attributes().
*/
static mmap_attr_t smc_attr_to_mmap_attr(unsigned int attributes)
{
mmap_attr_t tf_attr = 0;
unsigned int access = (attributes & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
>> SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;
if (access == SP_MEMORY_ATTRIBUTES_ACCESS_RW) {
tf_attr |= MT_RW | MT_USER;
} else if (access == SP_MEMORY_ATTRIBUTES_ACCESS_RO) {
tf_attr |= MT_RO | MT_USER;
} else {
/* Other values are reserved. */
assert(access == SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS);
/* The only requirement is that there's no access from EL0 */
tf_attr |= MT_RO | MT_PRIVILEGED;
}
if ((attributes & SP_MEMORY_ATTRIBUTES_NON_EXEC) == 0) {
tf_attr |= MT_EXECUTE;
} else {
tf_attr |= MT_EXECUTE_NEVER;
}
return tf_attr;
}
/*
* This function converts attributes from the Trusted Firmware format into the
* SMC interface format.
*/
static int smc_mmap_to_smc_attr(mmap_attr_t attr)
{
int smc_attr = 0;
int data_access;
if ((attr & MT_USER) == 0) {
/* No access from EL0. */
data_access = SP_MEMORY_ATTRIBUTES_ACCESS_NOACCESS;
} else {
if ((attr & MT_RW) != 0) {
assert(MT_TYPE(attr) != MT_DEVICE);
data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RW;
} else {
data_access = SP_MEMORY_ATTRIBUTES_ACCESS_RO;
}
}
smc_attr |= (data_access & SP_MEMORY_ATTRIBUTES_ACCESS_MASK)
<< SP_MEMORY_ATTRIBUTES_ACCESS_SHIFT;
if (attr & MT_EXECUTE_NEVER) {
smc_attr |= SP_MEMORY_ATTRIBUTES_NON_EXEC;
}
return smc_attr;
}
static int spm_memory_attributes_get_smc_handler(uintptr_t base_va)
{
spin_lock(&mem_attr_smc_lock);
mmap_attr_t attributes;
int rc = get_mem_attributes(secure_partition_xlat_ctx_handle,
base_va, &attributes);
spin_unlock(&mem_attr_smc_lock);
/* Convert error codes of get_mem_attributes() into SPM ones. */
assert(rc == 0 || rc == -EINVAL);
if (rc == 0) {
return smc_mmap_to_smc_attr(attributes);
} else {
return SPM_INVALID_PARAMETER;
}
}
static int spm_memory_attributes_set_smc_handler(u_register_t page_address,
u_register_t pages_count,
u_register_t smc_attributes)
{
uintptr_t base_va = (uintptr_t) page_address;
size_t size = (size_t) (pages_count * PAGE_SIZE);
unsigned int attributes = (unsigned int) smc_attributes;
INFO(" Start address : 0x%lx\n", base_va);
INFO(" Number of pages: %i (%zi bytes)\n", (int) pages_count, size);
INFO(" Attributes : 0x%x\n", attributes);
spin_lock(&mem_attr_smc_lock);
int ret = change_mem_attributes(secure_partition_xlat_ctx_handle,
base_va, size, smc_attr_to_mmap_attr(attributes));
spin_unlock(&mem_attr_smc_lock);
/* Convert error codes of change_mem_attributes() into SPM ones. */
assert(ret == 0 || ret == -EINVAL);
return (ret == 0) ? SPM_SUCCESS : SPM_INVALID_PARAMETER;
}
uint64_t spm_smc_handler(uint32_t smc_fid,
uint64_t x1,
uint64_t x2,
uint64_t x3,
uint64_t x4,
void *cookie,
void *handle,
uint64_t flags)
{
cpu_context_t *ns_cpu_context;
unsigned int ns;
/* Determine which security state this SMC originated from */
ns = is_caller_non_secure(flags);
if (ns == SMC_FROM_SECURE) {
/* Handle SMCs from Secure world. */
switch (smc_fid) {
case SPM_VERSION_AARCH32:
SMC_RET1(handle, SPM_VERSION_COMPILED);
case SP_EVENT_COMPLETE_AARCH64:
assert(handle == cm_get_context(SECURE));
cm_el1_sysregs_context_save(SECURE);
spm_setup_next_eret_into_sel0(handle);
if (sp_init_in_progress) {
/*
* SPM reports completion. The SPM must have
* initiated the original request through a
* synchronous entry into the secure
* partition. Jump back to the original C
* runtime context.
*/
spm_synchronous_sp_exit(&sp_ctx, x1);
assert(0);
}
/*
* This is the result from the Secure partition of an
* earlier request. Copy the result into the non-secure
* context, save the secure state and return to the
* non-secure state.
*/
/* Get a reference to the non-secure context */
ns_cpu_context = cm_get_context(NON_SECURE);
assert(ns_cpu_context);
/* Restore non-secure state */
cm_el1_sysregs_context_restore(NON_SECURE);
cm_set_next_eret_context(NON_SECURE);
/* Return to normal world */
SMC_RET1(ns_cpu_context, x1);
case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
INFO("Received SP_MEMORY_ATTRIBUTES_GET_AARCH64 SMC\n");
if (!sp_init_in_progress) {
WARN("SP_MEMORY_ATTRIBUTES_GET_AARCH64 is available at boot time only\n");
SMC_RET1(handle, SPM_NOT_SUPPORTED);
}
SMC_RET1(handle, spm_memory_attributes_get_smc_handler(x1));
case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
INFO("Received SP_MEMORY_ATTRIBUTES_SET_AARCH64 SMC\n");
if (!sp_init_in_progress) {
WARN("SP_MEMORY_ATTRIBUTES_SET_AARCH64 is available at boot time only\n");
SMC_RET1(handle, SPM_NOT_SUPPORTED);
}
SMC_RET1(handle, spm_memory_attributes_set_smc_handler(x1, x2, x3));
default:
break;
}
} else {
/* Handle SMCs from Non-secure world. */
switch (smc_fid) {
case SP_VERSION_AARCH64:
case SP_VERSION_AARCH32:
SMC_RET1(handle, SP_VERSION_COMPILED);
case MM_COMMUNICATE_AARCH32:
case MM_COMMUNICATE_AARCH64:
{
uint64_t mm_cookie = x1;
uint64_t comm_buffer_address = x2;
uint64_t comm_size_address = x3;
/* Cookie. Reserved for future use. It must be zero. */
if (mm_cookie != 0) {
ERROR("MM_COMMUNICATE: cookie is not zero\n");
SMC_RET1(handle, SPM_INVALID_PARAMETER);
}
if (comm_buffer_address == 0) {
ERROR("MM_COMMUNICATE: comm_buffer_address is zero\n");
SMC_RET1(handle, SPM_INVALID_PARAMETER);
}
if (comm_size_address != 0) {
VERBOSE("MM_COMMUNICATE: comm_size_address is not 0 as recommended.\n");
}
/* Save the Normal world context */
cm_el1_sysregs_context_save(NON_SECURE);
/*
* Restore the secure world context and prepare for
* entry in S-EL0
*/
assert(&sp_ctx.cpu_ctx == cm_get_context(SECURE));
cm_el1_sysregs_context_restore(SECURE);
cm_set_next_eret_context(SECURE);
SMC_RET4(&sp_ctx.cpu_ctx, smc_fid, comm_buffer_address,
comm_size_address, plat_my_core_pos());
}
case SP_MEMORY_ATTRIBUTES_GET_AARCH64:
case SP_MEMORY_ATTRIBUTES_SET_AARCH64:
/* SMC interfaces reserved for secure callers. */
SMC_RET1(handle, SPM_NOT_SUPPORTED);
default:
break;
}
}
SMC_RET1(handle, SMC_UNK);
}