[PATCH v2 0/4] Insure 16 alignment of reserved memory in board_f.c

Hi,
It is a V2, rebased on master branch, for the untitled serie http://patchwork.ozlabs.org/project/uboot/list/?series=152226
This serie now include the previous patch: [U-Boot,v3] board_f.c: Insure gd->new_bootstage alignment http://patchwork.ozlabs.org/patch/1201452/
After this first correction, I remove the stm32mp1 workaround as the issue of bootstage alignment is solved.
The 4th patch is a complete solution to alignment (proposed in comment 5 of http://patchwork.ozlabs.org/patch/1201452/#2327366) I always align the reserved memory to 16 bytes with a new function reserve_sp().
This patch causes an issue on ARM 32 bits, as the relocated gd pointer is not initialized with gd->new_gd as expected in reserve_global_data() but is hard-coded with relocated gd = gd->bd - GD_SIZE {with GD_SIZE = sizeof(struct global_data)}
This issue is solved with the 3rd patch of the serie arm: set the relocated gd with gd->new_gd
Only tested on STM32MP157C-EV1 board (ARM32 architecture).
Changes in v2: - import: [U-Boot,v3] board_f.c: Insure gd->new_bootstage alignment
Patrice Chotard (1): board_f.c: Insure gd->new_bootstage alignment
Patrick Delaunay (3): Revert "stm32mp1: remove the imply BOOTSTAGE" arm: set the relocated gd with gd->new_gd board_f.c: Insure 16 alignment of start_addr_sp and reserved memory
arch/arm/lib/crt0.S | 3 +-- arch/arm/mach-stm32mp/Kconfig | 2 ++ common/board_f.c | 27 ++++++++++++++++++--------- 3 files changed, 21 insertions(+), 11 deletions(-)

From: Patrice Chotard patrice.chotard@st.com
In reserve_bootstage(), in case size is odd, gd->new_bootstage is not aligned. In bootstage_relocate(), the platform hangs when getting access to data->record[i].name. To avoid this issue, make gd->new_bootstage 16 byte aligned.
To insure that new_bootstage is 16 byte aligned (at least needed for x86_64 and ARMv8) and new_bootstage starts down to get enough space, ALIGN_DOWN macro is used.
Fixes: ac9cd4805c8b ("bootstage: Correct relocation algorithm")
Signed-off-by: Patrice Chotard patrice.chotard@st.com Reviewed-by: Vikas MANOCHA vikas.manocha@st.com Reviewed-by: Patrick Delaunay patrick.delaunay@st.com Tested-by: Patrick Delaunay patrick.delaunay@st.com Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
Changes in v2: - import: [U-Boot,v3] board_f.c: Insure gd->new_bootstage alignment
common/board_f.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/common/board_f.c b/common/board_f.c index d66afb37ca..e21f533634 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -562,6 +562,11 @@ static int reserve_bootstage(void) 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->new_bootstage = map_sysmem(gd->start_addr_sp, size); debug("Reserving %#x Bytes for bootstage at: %08lx\n", size, gd->start_addr_sp);

On 1/22/20 6:52 AM, Patrick Delaunay wrote:
From: Patrice Chotard patrice.chotard@st.com
In reserve_bootstage(), in case size is odd, gd->new_bootstage is not aligned. In bootstage_relocate(), the platform hangs when getting access to data->record[i].name. To avoid this issue, make gd->new_bootstage 16 byte aligned.
To insure that new_bootstage is 16 byte aligned (at least needed for x86_64 and ARMv8) and new_bootstage starts down to get enough space, ALIGN_DOWN macro is used.
diff --git a/common/board_f.c b/common/board_f.c index d66afb37ca..e21f533634 100644 --- a/common/board_f.c +++ b/common/board_f.c @@ -562,6 +562,11 @@ static int reserve_bootstage(void) int size = bootstage_get_size();
gd->start_addr_sp -= size;
- /*
* Insure that start_addr_sp is aligned down to reserve enough
Nit: Ensure not insure (a pet peeve of mine!)
* space for new_bootstage
*/
- gd->start_addr_sp = ALIGN_DOWN(gd->start_addr_sp, 16); gd->new_bootstage = map_sysmem(gd->start_addr_sp, size); debug("Reserving %#x Bytes for bootstage at: %08lx\n", size, gd->start_addr_sp);

On Wed, 22 Jan 2020 at 06:52, Patrick Delaunay patrick.delaunay@st.com wrote:
From: Patrice Chotard patrice.chotard@st.com
In reserve_bootstage(), in case size is odd, gd->new_bootstage is not aligned. In bootstage_relocate(), the platform hangs when getting access to data->record[i].name. To avoid this issue, make gd->new_bootstage 16 byte aligned.
To insure that new_bootstage is 16 byte aligned (at least needed for x86_64 and ARMv8) and new_bootstage starts down to get enough space, ALIGN_DOWN macro is used.
Fixes: ac9cd4805c8b ("bootstage: Correct relocation algorithm")
Signed-off-by: Patrice Chotard patrice.chotard@st.com Reviewed-by: Vikas MANOCHA vikas.manocha@st.com Reviewed-by: Patrick Delaunay patrick.delaunay@st.com Tested-by: Patrick Delaunay patrick.delaunay@st.com Signed-off-by: Patrick Delaunay patrick.delaunay@st.com
Changes in v2:
- import: [U-Boot,v3] board_f.c: Insure gd->new_bootstage alignment
common/board_f.c | 5 +++++ 1 file changed, 5 insertions(+)
Ensure as Stephen says
With that fixed:
Reviewed-by: Simon Glass sjg@chromium.org

This reverts the workaround introduced by the commit 16fec9b0bc1a ("stm32mp1: remove the imply BOOTSTAGE") As the bootstage alignment issue is now solved.
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
Changes in v2: None
arch/arm/mach-stm32mp/Kconfig | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/arm/mach-stm32mp/Kconfig b/arch/arm/mach-stm32mp/Kconfig index ae28f6e206..e920b89ef5 100644 --- a/arch/arm/mach-stm32mp/Kconfig +++ b/arch/arm/mach-stm32mp/Kconfig @@ -46,7 +46,9 @@ config TARGET_STM32MP1 select STM32_SERIAL select SYS_ARCH_TIMER imply BOOTCOUNT_LIMIT + imply BOOTSTAGE imply CMD_BOOTCOUNT + imply CMD_BOOTSTAGE imply CMD_CLS if CMD_BMP imply DISABLE_CONSOLE imply PRE_CONSOLE_BUFFER

On Wed, 22 Jan 2020 at 06:52, Patrick Delaunay patrick.delaunay@st.com wrote:
This reverts the workaround introduced by the commit 16fec9b0bc1a ("stm32mp1: remove the imply BOOTSTAGE") As the bootstage alignment issue is now solved.
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com
Changes in v2: None
arch/arm/mach-stm32mp/Kconfig | 2 ++ 1 file changed, 2 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org

Simplify the arm relocation behavior and get gd directly form new_gd, as it is already done in crt0_64.S:
ldr x18, [x18, #GD_NEW_GD] /* x18 <- gd->new_gd */
This patch avoid assumption on new GD location (new GD is below bd - with #GD_SIZE offset).
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com ---
Changes in v2: None
arch/arm/lib/crt0.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/arch/arm/lib/crt0.S b/arch/arm/lib/crt0.S index fb6c37cf51..df9dd83e40 100644 --- a/arch/arm/lib/crt0.S +++ b/arch/arm/lib/crt0.S @@ -127,8 +127,7 @@ ENTRY(_main) ldr r0, [r9, #GD_START_ADDR_SP] /* sp = gd->start_addr_sp */ bic r0, r0, #7 /* 8-byte alignment for ABI compliance */ mov sp, r0 - ldr r9, [r9, #GD_BD] /* r9 = gd->bd */ - sub r9, r9, #GD_SIZE /* new GD is below bd */ + ldr r9, [r9, #GD_NEW_GD] /* r9 <- gd->new_gd */
adr lr, here ldr r0, [r9, #GD_RELOC_OFF] /* r0 = gd->reloc_off */

On Wed, 22 Jan 2020 at 06:52, Patrick Delaunay patrick.delaunay@st.com wrote:
Simplify the arm relocation behavior and get gd directly form new_gd, as it is already done in crt0_64.S:
ldr x18, [x18, #GD_NEW_GD] /* x18 <- gd->new_gd */
This patch avoid assumption on new GD location (new GD is below bd - with #GD_SIZE offset).
Signed-off-by: Patrick Delaunay patrick.delaunay@st.com
Changes in v2: None
arch/arm/lib/crt0.S | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)
Reviewed-by: Simon Glass sjg@chromium.org

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@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

On 1/22/20 6:52 AM, Patrick Delaunay wrote:
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.
diff --git a/common/board_f.c b/common/board_f.c
+/*
- 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)
Bikeshed: Not sure this name is very description. Perhaps reserve_stack_aligned() would be better. Not a big deal though. Patches 1,4 look fine otherwise.

Hi Stephen,
From: Stephen Warren swarren@wwwdotorg.org Sent: mercredi 22 janvier 2020 17:54
On 1/22/20 6:52 AM, Patrick Delaunay wrote:
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.
diff --git a/common/board_f.c b/common/board_f.c
+/*
- 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)
Bikeshed: Not sure this name is very description. Perhaps reserve_stack_aligned() would be better. Not a big deal though. Patches 1,4 look fine otherwise.
Yes and thanks, I will update the comment. I am waiting few day for sending v3.
Patrick
participants (4)
-
Patrick DELAUNAY
-
Patrick Delaunay
-
Simon Glass
-
Stephen Warren