aboutsummaryrefslogtreecommitdiff
path: root/common/bl_common.c
diff options
context:
space:
mode:
authorAchin Gupta <achin.gupta@arm.com>2013-10-25 09:08:21 +0100
committerJames Morrissey <james.morrissey@arm.com>2013-10-25 09:37:16 +0100
commit4f6ad66ae9fcc8bcb3b0fcee10b7ab1ffcaf1a56 (patch)
tree475db5d74370cb62b02afab0900774955a59702f /common/bl_common.c
downloadarm-trusted-firmware-4f6ad66ae9fcc8bcb3b0fcee10b7ab1ffcaf1a56.tar.gz
ARMv8 Trusted Firmware release v0.2v0.2
Diffstat (limited to 'common/bl_common.c')
-rw-r--r--common/bl_common.c516
1 files changed, 516 insertions, 0 deletions
diff --git a/common/bl_common.c b/common/bl_common.c
new file mode 100644
index 0000000..d125786
--- /dev/null
+++ b/common/bl_common.c
@@ -0,0 +1,516 @@
+/*
+ * Copyright (c) 2013, ARM Limited. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <arch_helpers.h>
+#include <console.h>
+#include <platform.h>
+#include <semihosting.h>
+#include <bl_common.h>
+#include <bl1.h>
+
+/***********************************************************
+ * Memory for sharing data while changing exception levels.
+ * Only used by the primary core.
+ **********************************************************/
+unsigned char bl2_el_change_mem_ptr[EL_CHANGE_MEM_SIZE];
+
+unsigned long *get_el_change_mem_ptr(void)
+{
+ return (unsigned long *) bl2_el_change_mem_ptr;
+}
+
+unsigned long page_align(unsigned long value, unsigned dir)
+{
+ unsigned long page_size = 1 << FOUR_KB_SHIFT;
+
+ /* Round up the limit to the next page boundary */
+ if (value & (page_size - 1)) {
+ value &= ~(page_size - 1);
+ if (dir == UP)
+ value += page_size;
+ }
+
+ return value;
+}
+
+static inline unsigned int is_page_aligned (unsigned long addr) {
+ const unsigned long page_size = 1 << FOUR_KB_SHIFT;
+
+ return (addr & (page_size - 1)) == 0;
+}
+
+void change_security_state(unsigned int target_security_state)
+{
+ unsigned long scr = read_scr();
+
+ if (target_security_state == SECURE)
+ scr &= ~SCR_NS_BIT;
+ else if (target_security_state == NON_SECURE)
+ scr |= SCR_NS_BIT;
+ else
+ assert(0);
+
+ write_scr(scr);
+}
+
+int drop_el(aapcs64_params *args,
+ unsigned long spsr,
+ unsigned long entrypoint)
+{
+ write_spsr(spsr);
+ write_elr(entrypoint);
+ eret(args->arg0,
+ args->arg1,
+ args->arg2,
+ args->arg3,
+ args->arg4,
+ args->arg5,
+ args->arg6,
+ args->arg7);
+ return -EINVAL;
+}
+
+long raise_el(aapcs64_params *args)
+{
+ return smc(args->arg0,
+ args->arg1,
+ args->arg2,
+ args->arg3,
+ args->arg4,
+ args->arg5,
+ args->arg6,
+ args->arg7);
+}
+
+/*
+ * TODO: If we are not EL3 then currently we only issue an SMC.
+ * Add support for dropping into EL0 etc. Consider adding support
+ * for switching from S-EL1 to S-EL0/1 etc.
+ */
+long change_el(el_change_info *info)
+{
+ unsigned long current_el = read_current_el();
+
+ if (GET_EL(current_el) == MODE_EL3) {
+ /*
+ * We can go anywhere from EL3. So find where.
+ * TODO: Lots to do if we are going non-secure.
+ * Flip the NS bit. Restore NS registers etc.
+ * Just doing the bare minimal for now.
+ */
+
+ if (info->security_state == NON_SECURE)
+ change_security_state(info->security_state);
+
+ return drop_el(&info->args, info->spsr, info->entrypoint);
+ } else
+ return raise_el(&info->args);
+}
+
+/* TODO: add a parameter for DAIF. not needed right now */
+unsigned long make_spsr(unsigned long target_el,
+ unsigned long target_sp,
+ unsigned long target_rw)
+{
+ unsigned long spsr;
+
+ /* Disable all exceptions & setup the EL */
+ spsr = (DAIF_FIQ_BIT | DAIF_IRQ_BIT | DAIF_ABT_BIT | DAIF_DBG_BIT)
+ << PSR_DAIF_SHIFT;
+ spsr |= PSR_MODE(target_rw, target_el, target_sp);
+
+ return spsr;
+}
+
+/*******************************************************************************
+ * The next two functions are the weak definitions. Platform specific
+ * code can override them if it wishes to.
+ ******************************************************************************/
+
+/*******************************************************************************
+ * Function that takes a memory layout into which BL31 has been either top or
+ * bottom loaded. Using this information, it populates bl31_mem_layout to tell
+ * BL31 how much memory it has access to and how much is available for use. It
+ * does not need the address where BL31 has been loaded as BL31 will reclaim
+ * all the memory used by BL2.
+ * TODO: Revisit if this and init_bl2_mem_layout can be replaced by a single
+ * routine.
+ ******************************************************************************/
+void init_bl31_mem_layout(const meminfo *bl2_mem_layout,
+ meminfo *bl31_mem_layout,
+ unsigned int load_type)
+{
+ if (load_type == BOT_LOAD) {
+ /*
+ * ------------ ^
+ * | BL2 | |
+ * |----------| ^ | BL2
+ * | | | BL2 free | total
+ * | | | size | size
+ * |----------| BL2 free base v |
+ * | BL31 | |
+ * ------------ BL2 total base v
+ */
+ unsigned long bl31_size;
+
+ bl31_mem_layout->free_base = bl2_mem_layout->free_base;
+
+ bl31_size = bl2_mem_layout->free_base - bl2_mem_layout->total_base;
+ bl31_mem_layout->free_size = bl2_mem_layout->total_size - bl31_size;
+ } else {
+ /*
+ * ------------ ^
+ * | BL31 | |
+ * |----------| ^ | BL2
+ * | | | BL2 free | total
+ * | | | size | size
+ * |----------| BL2 free base v |
+ * | BL2 | |
+ * ------------ BL2 total base v
+ */
+ unsigned long bl2_size;
+
+ bl31_mem_layout->free_base = bl2_mem_layout->total_base;
+
+ bl2_size = bl2_mem_layout->free_base - bl2_mem_layout->total_base;
+ bl31_mem_layout->free_size = bl2_mem_layout->free_size + bl2_size;
+ }
+
+ bl31_mem_layout->total_base = bl2_mem_layout->total_base;
+ bl31_mem_layout->total_size = bl2_mem_layout->total_size;
+ bl31_mem_layout->attr = load_type;
+
+ flush_dcache_range((unsigned long) bl31_mem_layout, sizeof(meminfo));
+ return;
+}
+
+/*******************************************************************************
+ * Function that takes a memory layout into which BL2 has been either top or
+ * bottom loaded along with the address where BL2 has been loaded in it. Using
+ * this information, it populates bl2_mem_layout to tell BL2 how much memory
+ * it has access to and how much is available for use.
+ ******************************************************************************/
+void init_bl2_mem_layout(meminfo *bl1_mem_layout,
+ meminfo *bl2_mem_layout,
+ unsigned int load_type,
+ unsigned long bl2_base)
+{
+ unsigned tmp;
+
+ if (load_type == BOT_LOAD) {
+ bl2_mem_layout->total_base = bl2_base;
+ tmp = bl1_mem_layout->free_base - bl2_base;
+ bl2_mem_layout->total_size = bl1_mem_layout->free_size + tmp;
+
+ } else {
+ bl2_mem_layout->total_base = bl1_mem_layout->free_base;
+ tmp = bl1_mem_layout->total_base + bl1_mem_layout->total_size;
+ bl2_mem_layout->total_size = tmp - bl1_mem_layout->free_base;
+ }
+
+ bl2_mem_layout->free_base = bl1_mem_layout->free_base;
+ bl2_mem_layout->free_size = bl1_mem_layout->free_size;
+ bl2_mem_layout->attr = load_type;
+
+ flush_dcache_range((unsigned long) bl2_mem_layout, sizeof(meminfo));
+ return;
+}
+
+static void dump_load_info(unsigned long image_load_addr,
+ unsigned long image_size,
+ const meminfo *mem_layout)
+{
+#if DEBUG
+ printf("Trying to load image at address 0x%lx, size = 0x%lx\r\n",
+ image_load_addr, image_size);
+ printf("Current memory layout:\r\n");
+ printf(" total region = [0x%lx, 0x%lx]\r\n", mem_layout->total_base,
+ mem_layout->total_base + mem_layout->total_size);
+ printf(" free region = [0x%lx, 0x%lx]\r\n", mem_layout->free_base,
+ mem_layout->free_base + mem_layout->free_size);
+#endif
+}
+
+/*******************************************************************************
+ * Generic function to load an image into the trusted RAM using semihosting
+ * given a name, extents of free memory & whether the image should be loaded at
+ * the bottom or top of the free memory. It updates the memory layout if the
+ * load is successful.
+ ******************************************************************************/
+unsigned long load_image(meminfo *mem_layout,
+ const char *image_name,
+ unsigned int load_type,
+ unsigned long fixed_addr)
+{
+ unsigned long temp_image_base, image_base;
+ long offset;
+ int image_flen;
+
+ /* Find the size of the image */
+ image_flen = semihosting_get_flen(image_name);
+ if (image_flen < 0) {
+ printf("ERROR: Cannot access '%s' file (%i).\r\n",
+ image_name, image_flen);
+ return 0;
+ }
+
+ /* See if we have enough space */
+ if (image_flen > mem_layout->free_size) {
+ printf("ERROR: Cannot load '%s' file: Not enough space.\r\n",
+ image_name);
+ dump_load_info(0, image_flen, mem_layout);
+ return 0;
+ }
+
+ switch (load_type) {
+
+ case TOP_LOAD:
+
+ /* Load the image in the top of free memory */
+ temp_image_base = mem_layout->free_base + mem_layout->free_size;
+ temp_image_base -= image_flen;
+
+ /* Page align base address and check whether the image still fits */
+ image_base = page_align(temp_image_base, DOWN);
+ assert(image_base <= temp_image_base);
+
+ if (image_base < mem_layout->free_base) {
+ printf("ERROR: Cannot load '%s' file: Not enough space.\r\n",
+ image_name);
+ dump_load_info(image_base, image_flen, mem_layout);
+ return 0;
+ }
+
+ /* Calculate the amount of extra memory used due to alignment */
+ offset = temp_image_base - image_base;
+
+ break;
+
+ case BOT_LOAD:
+
+ /* Load the BL2 image in the bottom of free memory */
+ temp_image_base = mem_layout->free_base;
+ image_base = page_align(temp_image_base, UP);
+ assert(image_base >= temp_image_base);
+
+ /* Page align base address and check whether the image still fits */
+ if (image_base + image_flen >
+ mem_layout->free_base + mem_layout->free_size) {
+ printf("ERROR: Cannot load '%s' file: Not enough space.\r\n",
+ image_name);
+ dump_load_info(image_base, image_flen, mem_layout);
+ return 0;
+ }
+
+ /* Calculate the amount of extra memory used due to alignment */
+ offset = image_base - temp_image_base;
+
+ break;
+
+ default:
+ assert(0);
+
+ }
+
+ /*
+ * Some images must be loaded at a fixed address, not a dynamic one.
+ *
+ * This has been implemented as a hack on top of the existing dynamic
+ * loading mechanism, for the time being. If the 'fixed_addr' function
+ * argument is different from zero, then it will force the load address.
+ * So we still have this principle of top/bottom loading but the code
+ * determining the load address is bypassed and the load address is
+ * forced to the fixed one.
+ *
+ * This can result in quite a lot of wasted space because we still use
+ * 1 sole meminfo structure to represent the extents of free memory,
+ * where we should use some sort of linked list.
+ *
+ * E.g. we want to load BL2 at address 0x04020000, the resulting memory
+ * layout should look as follows:
+ * ------------ 0x04040000
+ * | | <- Free space (1)
+ * |----------|
+ * | BL2 |
+ * |----------| 0x04020000
+ * | | <- Free space (2)
+ * |----------|
+ * | BL1 |
+ * ------------ 0x04000000
+ *
+ * But in the current hacky implementation, we'll need to specify
+ * whether BL2 is loaded at the top or bottom of the free memory.
+ * E.g. if BL2 is considered as top-loaded, the meminfo structure
+ * will give the following view of the memory, hiding the chunk of
+ * free memory above BL2:
+ * ------------ 0x04040000
+ * | |
+ * | |
+ * | BL2 |
+ * |----------| 0x04020000
+ * | | <- Free space (2)
+ * |----------|
+ * | BL1 |
+ * ------------ 0x04000000
+ */
+ if (fixed_addr != 0) {
+ /* Load the image at the given address. */
+ image_base = fixed_addr;
+
+ /* Check whether the image fits. */
+ if ((image_base < mem_layout->free_base) ||
+ (image_base + image_flen >
+ mem_layout->free_base + mem_layout->free_size)) {
+ printf("ERROR: Cannot load '%s' file: Not enough space.\r\n",
+ image_name);
+ dump_load_info(image_base, image_flen, mem_layout);
+ return 0;
+ }
+
+ /* Check whether the fixed load address is page-aligned. */
+ if (!is_page_aligned(image_base)) {
+ printf("ERROR: Cannot load '%s' file at unaligned address 0x%lx.\r\n",
+ image_name, fixed_addr);
+ return 0;
+ }
+
+ /*
+ * Calculate the amount of extra memory used due to fixed
+ * loading.
+ */
+ if (load_type == TOP_LOAD) {
+ unsigned long max_addr, space_used;
+ /*
+ * ------------ max_addr
+ * | /wasted/ | | offset
+ * |..........|..............................
+ * | image | | image_flen
+ * |----------| fixed_addr
+ * | |
+ * | |
+ * ------------ total_base
+ */
+ max_addr = mem_layout->total_base + mem_layout->total_size;
+ /*
+ * Compute the amount of memory used by the image.
+ * Corresponds to all space above the image load
+ * address.
+ */
+ space_used = max_addr - fixed_addr;
+ /*
+ * Calculate the amount of wasted memory within the
+ * amount of memory used by the image.
+ */
+ offset = space_used - image_flen;
+ } else /* BOT_LOAD */
+ /*
+ * ------------
+ * | |
+ * | |
+ * |----------|
+ * | image |
+ * |..........| fixed_addr
+ * | /wasted/ | | offset
+ * ------------ total_base
+ */
+ offset = fixed_addr - mem_layout->total_base;
+ }
+
+ /* We have enough space so load the image now */
+ image_flen = semihosting_download_file(image_name,
+ image_flen,
+ (void *) image_base);
+ if (image_flen <= 0) {
+ printf("ERROR: Failed to load '%s' file from semihosting (%i).\r\n",
+ image_name, image_flen);
+ return 0;
+ }
+
+ /*
+ * File has been successfully loaded. Update the free memory
+ * data structure & flush the contents of the TZRAM so that
+ * the next EL can see it.
+ */
+ /* Update the memory contents */
+ flush_dcache_range(image_base, image_flen);
+
+ mem_layout->free_size -= image_flen + offset;
+
+ /* Update the base of free memory since its moved up */
+ if (load_type == BOT_LOAD)
+ mem_layout->free_base += offset + image_flen;
+
+ return image_base;
+}
+
+/*******************************************************************************
+ * Run a loaded image from the given entry point. This could result in either
+ * dropping into a lower exception level or jumping to a higher exception level.
+ * The only way of doing the latter is through an SMC. In either case, setup the
+ * parameters for the EL change request correctly.
+ ******************************************************************************/
+int run_image(unsigned long entrypoint,
+ unsigned long spsr,
+ unsigned long target_security_state,
+ meminfo *mem_layout,
+ void *data)
+{
+ el_change_info run_image_info;
+ unsigned long current_el = read_current_el();
+
+ /* Tell next EL what we want done */
+ run_image_info.args.arg0 = RUN_IMAGE;
+ run_image_info.entrypoint = entrypoint;
+ run_image_info.spsr = spsr;
+ run_image_info.security_state = target_security_state;
+ run_image_info.next = 0;
+
+ /*
+ * If we are EL3 then only an eret can take us to the desired
+ * exception level. Else for the time being assume that we have
+ * to jump to a higher EL and issue an SMC. Contents of argY
+ * will go into the general purpose register xY e.g. arg0->x0
+ */
+ if (GET_EL(current_el) == MODE_EL3) {
+ run_image_info.args.arg1 = (unsigned long) mem_layout;
+ run_image_info.args.arg2 = (unsigned long) data;
+ } else {
+ run_image_info.args.arg1 = entrypoint;
+ run_image_info.args.arg2 = spsr;
+ run_image_info.args.arg3 = (unsigned long) mem_layout;
+ run_image_info.args.arg4 = (unsigned long) data;
+ }
+
+ return change_el(&run_image_info);
+}