[PATCH v2 4/4] board_f.c: Insure 16 alignment of start_addr_sp and reserved memory
Patrick Delaunay
patrick.delaunay at st.com
Wed Jan 22 14:52:43 CET 2020
Add a function reserve_sp() to reserved memory with 16 bits alignment
after the stack pointer (gd->start_addr_sp) and use this new function
in board_f.c to reserve all the memory area (malloc, board, gd, fdt,
bootstage, stacks).
This 16 byte alignment is needed for cast on struct pointer
for the reserved memory, for example:
+ x86_64 ABI: https://reviews.llvm.org/D30049: 16 bytes
+ ARMv8 Instruction Set Overview: quad word, 16 bytes
An other alignment value could be needed for other architecture.
Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
---
Changes in v2: None
common/board_f.c | 32 ++++++++++++++++++--------------
1 file changed, 18 insertions(+), 14 deletions(-)
diff --git a/common/board_f.c b/common/board_f.c
index e21f533634..0302ee4a6e 100644
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -470,6 +470,17 @@ static int reserve_uboot(void)
return 0;
}
+/*
+ * reserve after start_addr_sp the requested size and make the stack pointer
+ * 16-byte aligned, this alignment is needed for cast on the reserved memory
+ * ref = x86_64 ABI: https://reviews.llvm.org/D30049: 16 bytes
+ * = ARMv8 Instruction Set Overview: quad word, 16 bytes
+ */
+static unsigned long reserve_sp(size_t size)
+{
+ return ALIGN_DOWN(gd->start_addr_sp - size, 16);
+}
+
#ifdef CONFIG_SYS_NONCACHED_MEMORY
static int reserve_noncached(void)
{
@@ -495,7 +506,7 @@ static int reserve_noncached(void)
/* reserve memory for malloc() area */
static int reserve_malloc(void)
{
- gd->start_addr_sp = gd->start_addr_sp - TOTAL_MALLOC_LEN;
+ gd->start_addr_sp = reserve_sp(TOTAL_MALLOC_LEN);
debug("Reserving %dk for malloc() at: %08lx\n",
TOTAL_MALLOC_LEN >> 10, gd->start_addr_sp);
#ifdef CONFIG_SYS_NONCACHED_MEMORY
@@ -509,7 +520,7 @@ static int reserve_malloc(void)
static int reserve_board(void)
{
if (!gd->bd) {
- gd->start_addr_sp -= sizeof(bd_t);
+ gd->start_addr_sp = reserve_sp(sizeof(bd_t));
gd->bd = (bd_t *)map_sysmem(gd->start_addr_sp, sizeof(bd_t));
memset(gd->bd, '\0', sizeof(bd_t));
debug("Reserving %zu Bytes for Board Info at: %08lx\n",
@@ -528,7 +539,7 @@ static int setup_machine(void)
static int reserve_global_data(void)
{
- gd->start_addr_sp -= sizeof(gd_t);
+ gd->start_addr_sp = reserve_sp(sizeof(gd_t));
gd->new_gd = (gd_t *)map_sysmem(gd->start_addr_sp, sizeof(gd_t));
debug("Reserving %zu Bytes for Global Data at: %08lx\n",
sizeof(gd_t), gd->start_addr_sp);
@@ -546,7 +557,7 @@ static int reserve_fdt(void)
if (gd->fdt_blob) {
gd->fdt_size = ALIGN(fdt_totalsize(gd->fdt_blob) + 0x1000, 32);
- gd->start_addr_sp -= gd->fdt_size;
+ gd->start_addr_sp = reserve_sp(gd->fdt_size);
gd->new_fdt = map_sysmem(gd->start_addr_sp, gd->fdt_size);
debug("Reserving %lu Bytes for FDT at: %08lx\n",
gd->fdt_size, gd->start_addr_sp);
@@ -561,12 +572,7 @@ static int reserve_bootstage(void)
#ifdef CONFIG_BOOTSTAGE
int size = bootstage_get_size();
- gd->start_addr_sp -= size;
- /*
- * Insure that start_addr_sp is aligned down to reserve enough
- * space for new_bootstage
- */
- gd->start_addr_sp = ALIGN_DOWN(gd->start_addr_sp, 16);
+ gd->start_addr_sp = reserve_sp(size);
gd->new_bootstage = map_sysmem(gd->start_addr_sp, size);
debug("Reserving %#x Bytes for bootstage at: %08lx\n", size,
gd->start_addr_sp);
@@ -583,8 +589,7 @@ __weak int arch_reserve_stacks(void)
static int reserve_stacks(void)
{
/* make stack pointer 16-byte aligned */
- gd->start_addr_sp -= 16;
- gd->start_addr_sp &= ~0xf;
+ gd->start_addr_sp = reserve_sp(16);
/*
* let the architecture-specific code tailor gd->start_addr_sp and
@@ -596,8 +601,7 @@ static int reserve_stacks(void)
static int reserve_bloblist(void)
{
#ifdef CONFIG_BLOBLIST
- gd->start_addr_sp &= ~0xf;
- gd->start_addr_sp -= CONFIG_BLOBLIST_SIZE;
+ gd->start_addr_sp = reserve_sp(CONFIG_BLOBLIST_SIZE);
gd->new_bloblist = map_sysmem(gd->start_addr_sp, CONFIG_BLOBLIST_SIZE);
#endif
--
2.17.1
More information about the U-Boot
mailing list