* [Qemu-devel] [PATCH v4 0/3] Add a generic loader
@ 2016-03-03 19:42 Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 1/3] loader: Allow ELF loader to auto-detect the ELF arch Alistair Francis
` (3 more replies)
0 siblings, 4 replies; 7+ messages in thread
From: Alistair Francis @ 2016-03-03 19:42 UTC (permalink / raw)
To: qemu-devel
Cc: peter.maydell, armbru, alistair.francis, crosthwaitepeter, cov,
pbonzini, afaerber
This work is based on the original work by Li Guang with extra
features added by Peter C and myself.
The idea of this loader is to allow the user to load multiple images
or values into QEMU at startup.
Memory values can be loaded like this: -device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
Images can be loaded like this: -device loader,file=./images/u-boot.elf,cpu=0
This can be useful and we use it a lot in Xilinx to load multiple images
into a machine at creation (ATF, Kernel and DTB for example).
It can also be used to set registers.
This patch series also make the load_elf() function more generic by not
requiring an architecture.
V4:
- Re-write documentation
- Allow the loader to work with every architecture
- Move the file to hw/core
- Increase the maximum number of CPUs
- Make the CPU operations conditional
- Convert the cpu option to cpu-num
- Require the user to specify endianess
V2:
- Add an entry to the maintainers file
- Add some documentation
- Perform bounds checking on the data_len
- Register and unregister the reset in the realise/unrealise
Changes since RFC:
- Add support for BE
Alistair Francis (3):
loader: Allow ELF loader to auto-detect the ELF arch
generic-loader: Add a generic loader
docs: Add a generic loader explanation document
MAINTAINERS | 6 ++
docs/generic-loader.txt | 56 +++++++++++++++
hw/core/Makefile.objs | 2 +
hw/core/generic-loader.c | 144 +++++++++++++++++++++++++++++++++++++++
hw/core/loader.c | 10 +++
include/hw/core/generic-loader.h | 45 ++++++++++++
6 files changed, 263 insertions(+)
create mode 100644 docs/generic-loader.txt
create mode 100644 hw/core/generic-loader.c
create mode 100644 include/hw/core/generic-loader.h
--
2.5.0
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v4 1/3] loader: Allow ELF loader to auto-detect the ELF arch
2016-03-03 19:42 [Qemu-devel] [PATCH v4 0/3] Add a generic loader Alistair Francis
@ 2016-03-03 19:42 ` Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 2/3] generic-loader: Add a generic loader Alistair Francis
` (2 subsequent siblings)
3 siblings, 0 replies; 7+ messages in thread
From: Alistair Francis @ 2016-03-03 19:42 UTC (permalink / raw)
To: qemu-devel
Cc: peter.maydell, armbru, alistair.francis, crosthwaitepeter, cov,
pbonzini, afaerber
If the caller didn't specify an architecture for the ELF machine
the load_elf() function will auto detect it based on the ELF file.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
---
hw/core/loader.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 3a57415..3a50771 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -339,6 +339,7 @@ int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t),
{
int fd, data_order, target_data_order, must_swab, ret = ELF_LOAD_FAILED;
uint8_t e_ident[EI_NIDENT];
+ uint16_t e_machine;
fd = open(filename, O_RDONLY | O_BINARY);
if (fd < 0) {
@@ -371,6 +372,15 @@ int load_elf(const char *filename, uint64_t (*translate_fn)(void *, uint64_t),
goto fail;
}
+ if (elf_machine < 1) {
+ /* The caller didn't specify and ARCH, we can figure it out */
+ lseek(fd, 0x12, SEEK_SET);
+ if (read(fd, &e_machine, sizeof(e_machine)) != sizeof(e_machine)) {
+ goto fail;
+ }
+ elf_machine = e_machine;
+ }
+
lseek(fd, 0, SEEK_SET);
if (e_ident[EI_CLASS] == ELFCLASS64) {
ret = load_elf64(filename, fd, translate_fn, translate_opaque, must_swab,
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v4 2/3] generic-loader: Add a generic loader
2016-03-03 19:42 [Qemu-devel] [PATCH v4 0/3] Add a generic loader Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 1/3] loader: Allow ELF loader to auto-detect the ELF arch Alistair Francis
@ 2016-03-03 19:42 ` Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 3/3] docs: Add a generic loader explanation document Alistair Francis
2016-03-16 12:03 ` [Qemu-devel] [PATCH v4 0/3] Add a generic loader Peter Maydell
3 siblings, 0 replies; 7+ messages in thread
From: Alistair Francis @ 2016-03-03 19:42 UTC (permalink / raw)
To: qemu-devel
Cc: peter.maydell, armbru, alistair.francis, crosthwaitepeter, cov,
pbonzini, afaerber
Add a generic loader to QEMU which can be used to load images or set
memory values.
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
---
V4:
- Allow the loader to work with every architecture
- Move the file to hw/core
- Increase the maximum number of CPUs
- Make the CPU operations conditional
- Convert the cpu option to cpu-num
- Require the user to specify endianess
V3:
- Pass the ram_size to load_image_targphys()
V2:
- Add maintainers entry
- Perform bounds checking
- Register and unregister the reset in the realise/unrealise
Changes since RFC:
- Add BE support
MAINTAINERS | 6 ++
hw/core/Makefile.objs | 2 +
hw/core/generic-loader.c | 144 +++++++++++++++++++++++++++++++++++++++
include/hw/core/generic-loader.h | 45 ++++++++++++
4 files changed, 197 insertions(+)
create mode 100644 hw/core/generic-loader.c
create mode 100644 include/hw/core/generic-loader.h
diff --git a/MAINTAINERS b/MAINTAINERS
index a5853cd..337cc1b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -971,6 +971,12 @@ F: hw/acpi/nvdimm.c
F: hw/mem/nvdimm.c
F: include/hw/mem/nvdimm.h
+Generic Loader
+M: Alistair Francis <alistair.francis@xilinx.com>
+S: Maintained
+F: hw/core/generic-loader.c
+F: include/hw/core/generic-loader.h
+
Subsystems
----------
Audio
diff --git a/hw/core/Makefile.objs b/hw/core/Makefile.objs
index abb3560..b5d5197 100644
--- a/hw/core/Makefile.objs
+++ b/hw/core/Makefile.objs
@@ -15,3 +15,5 @@ common-obj-$(CONFIG_SOFTMMU) += null-machine.o
common-obj-$(CONFIG_SOFTMMU) += loader.o
common-obj-$(CONFIG_SOFTMMU) += qdev-properties-system.o
common-obj-$(CONFIG_PLATFORM_BUS) += platform-bus.o
+
+obj-$(CONFIG_SOFTMMU) += generic-loader.o
diff --git a/hw/core/generic-loader.c b/hw/core/generic-loader.c
new file mode 100644
index 0000000..1b21934
--- /dev/null
+++ b/hw/core/generic-loader.c
@@ -0,0 +1,144 @@
+/*
+ * Generic Loader
+ *
+ * Copyright (C) 2014 Li Guang
+ * Copyright (C) 2016 Xilinx Inc.
+ * Written by Li Guang <lig.fnst@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/sysbus.h"
+#include "sysemu/dma.h"
+#include "hw/loader.h"
+#include "hw/core/generic-loader.h"
+
+#define CPU_NONE 0xFFFF
+
+static void generic_loader_reset(void *opaque)
+{
+ GenericLoaderState *s = GENERIC_LOADER(opaque);
+
+ if (s->cpu) {
+ CPUClass *cc = CPU_GET_CLASS(s->cpu);
+ cpu_reset(s->cpu);
+ if (cc) {
+ cc->set_pc(s->cpu, s->addr);
+ }
+ }
+
+ if (s->data_len) {
+ assert(s->data_len < sizeof(s->data));
+ dma_memory_write((s->cpu ? s->cpu : first_cpu)->as, s->addr, &s->data,
+ s->data_len);
+ }
+}
+
+static void generic_loader_realize(DeviceState *dev, Error **errp)
+{
+ GenericLoaderState *s = GENERIC_LOADER(dev);
+ hwaddr entry;
+ int big_endian;
+ int size = 0;
+
+ qemu_register_reset(generic_loader_reset, dev);
+
+ if (s->cpu_num != CPU_NONE) {
+ s->cpu = qemu_get_cpu(s->cpu_num);
+ if (!s->cpu) {
+ error_setg(errp, "Specified boot CPU#%d is nonexistent",
+ s->cpu_num);
+ return;
+ }
+ }
+
+#ifdef TARGET_WORDS_BIGENDIAN
+ big_endian = 1;
+#else
+ big_endian = 0;
+#endif
+
+ if (s->file) {
+ if (!s->force_raw) {
+ size = load_elf(s->file, NULL, NULL, &entry, NULL, NULL,
+ big_endian, 0, 0);
+
+ if (size < 0) {
+ size = load_uimage(s->file, &entry, NULL, NULL, NULL, NULL);
+ }
+ }
+
+ if (size < 0) {
+ /* Default to the maximum size being the machine's ram size */
+ size = load_image_targphys(s->file, s->addr, ram_size);
+ } else {
+ s->addr = entry;
+ }
+
+ if (size < 0) {
+ error_setg(errp, "Cannot load specified image %s", s->file);
+ return;
+ }
+ }
+
+ if (s->data_len && (s->data_len > sizeof(s->data))) {
+ error_setg(errp, "data-len cannot be more then the data size");
+ return;
+ }
+
+ /* Convert the data endiannes */
+ if (s->data_be) {
+ s->data = cpu_to_be64(s->data);
+ } else {
+ s->data = cpu_to_le64(s->data);
+ }
+}
+
+static void generic_loader_unrealize(DeviceState *dev, Error **errp)
+{
+ qemu_unregister_reset(generic_loader_reset, dev);
+}
+
+static Property generic_loader_props[] = {
+ DEFINE_PROP_UINT64("addr", GenericLoaderState, addr, 0),
+ DEFINE_PROP_UINT64("data", GenericLoaderState, data, 0),
+ DEFINE_PROP_UINT8("data-len", GenericLoaderState, data_len, 0),
+ DEFINE_PROP_BOOL("data-be", GenericLoaderState, data_be, false),
+ DEFINE_PROP_UINT16("cpu-num", GenericLoaderState, cpu_num, CPU_NONE),
+ DEFINE_PROP_BOOL("force-raw", GenericLoaderState, force_raw, false),
+ DEFINE_PROP_STRING("file", GenericLoaderState, file),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void generic_loader_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->realize = generic_loader_realize;
+ dc->unrealize = generic_loader_unrealize;
+ dc->props = generic_loader_props;
+ dc->desc = "Generic Loader";
+}
+
+static TypeInfo generic_loader_info = {
+ .name = TYPE_GENERIC_LOADER,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(GenericLoaderState),
+ .class_init = generic_loader_class_init,
+};
+
+static void generic_loader_register_type(void)
+{
+ type_register_static(&generic_loader_info);
+}
+
+type_init(generic_loader_register_type)
diff --git a/include/hw/core/generic-loader.h b/include/hw/core/generic-loader.h
new file mode 100644
index 0000000..ceec51f
--- /dev/null
+++ b/include/hw/core/generic-loader.h
@@ -0,0 +1,45 @@
+/*
+ * Generic Loader
+ *
+ * Copyright (C) 2014 Li Guang
+ * Written by Li Guang <lig.fnst@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#ifndef GENERIC_LOADER_H
+#define GENERIC_LOADER_H
+
+#include "elf.h"
+
+typedef struct GenericLoaderState {
+ /* <private> */
+ DeviceState parent_obj;
+
+ /* <public> */
+ CPUState *cpu;
+
+ uint64_t addr;
+ uint64_t data;
+ uint8_t data_len;
+ uint16_t cpu_num;
+
+ char *file;
+
+ bool force_raw;
+ bool data_be;
+} GenericLoaderState;
+
+#define TYPE_GENERIC_LOADER "loader"
+#define GENERIC_LOADER(obj) OBJECT_CHECK(GenericLoaderState, (obj), \
+ TYPE_GENERIC_LOADER)
+
+#endif
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v4 3/3] docs: Add a generic loader explanation document
2016-03-03 19:42 [Qemu-devel] [PATCH v4 0/3] Add a generic loader Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 1/3] loader: Allow ELF loader to auto-detect the ELF arch Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 2/3] generic-loader: Add a generic loader Alistair Francis
@ 2016-03-03 19:42 ` Alistair Francis
2016-03-16 12:03 ` [Qemu-devel] [PATCH v4 0/3] Add a generic loader Peter Maydell
3 siblings, 0 replies; 7+ messages in thread
From: Alistair Francis @ 2016-03-03 19:42 UTC (permalink / raw)
To: qemu-devel
Cc: peter.maydell, armbru, alistair.francis, crosthwaitepeter, cov,
pbonzini, afaerber
Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
---
V4:
- Re-write to be more comprehensive
docs/generic-loader.txt | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 56 insertions(+)
create mode 100644 docs/generic-loader.txt
diff --git a/docs/generic-loader.txt b/docs/generic-loader.txt
new file mode 100644
index 0000000..b748f2a
--- /dev/null
+++ b/docs/generic-loader.txt
@@ -0,0 +1,56 @@
+Copyright (c) 2016 Xilinx Inc.
+
+This work is licensed under the terms of the GNU GPL, version 2 or later. See
+the COPYING file in the top-level directory.
+
+
+The 'loader' device allows the user to load multiple images or values into
+QEMU at startup.
+
+Loading Memory Values
+---------------------------
+The loader device allows memory values to be set from the command line. This
+can be done by following the syntax below:
+
+ -device loader,addr=<addr>,data=<data>,data-len=<len>
+ -device loader,addr=<addr>,cpu-num=<cpu-num>
+
+NOTE: The loader device supports other options (see the next section) but they
+ do not apply to setting memory values and will be ignored.
+ It is also possible to mix the commands above, e.g. include the cpu-num
+ argument with the data argument.
+
+ <addr> - The address to store the data or the value to set the CPUs PC
+ <data> - The value to be written to the addr. The maximum size of the
+ data is 8 bytes.
+ <data-len> - The length of the data in bytes. This argument must be included
+ if the data argument is.
+ <data-be> - Set to true if the data to be stored on the guest should be
+ written as big endian data. The default is to write little
+ endian data.
+ <cpu-num> - This will cause the CPU to be reset and the PC to be set to
+ the value of addr.
+
+An example of loading value 0x8000000e to address 0xfd1a0104 is:
+ -device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
+
+Loading Files
+---------------------------
+The loader device also allows files to be loaded into memory. This can be done
+similarly to setting memory values. The syntax is shown below:
+
+ -device loader,file=<file>,addr=<addr>,cpu-num=<cpu-num>,force-raw=<raw>
+
+ <file> - A file to be loaded into memory
+ <addr> - The addr in memory that the file should be loaded. This is
+ ignored if you are using an ELF (unless force-raw is true).
+ This is requried if you aren't loading an ELF.
+ <cpu-num> - This specifices the CPU that should be used. This is an
+ optional argument and will cause the CPU's PC to be set to
+ where the image is stored. This option should only be used
+ for the boot image.
+ <force-raw> - Forces the file to be treated as a raw image. This can be
+ used to specificy the load address of ELF files.
+
+An example of loading an ELF file which CPU0 will boot is shown below:
+ -device loader,file=./images/boot.elf,cpu-num=0
--
2.5.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v4 0/3] Add a generic loader
2016-03-03 19:42 [Qemu-devel] [PATCH v4 0/3] Add a generic loader Alistair Francis
` (2 preceding siblings ...)
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 3/3] docs: Add a generic loader explanation document Alistair Francis
@ 2016-03-16 12:03 ` Peter Maydell
2016-03-16 17:18 ` Alistair Francis
3 siblings, 1 reply; 7+ messages in thread
From: Peter Maydell @ 2016-03-16 12:03 UTC (permalink / raw)
To: Alistair Francis
Cc: QEMU Developers, Markus Armbruster, Peter Crosthwaite,
Christopher Covington, Paolo Bonzini, Andreas Färber
On 3 March 2016 at 19:42, Alistair Francis <alistair.francis@xilinx.com> wrote:
> This work is based on the original work by Li Guang with extra
> features added by Peter C and myself.
>
> The idea of this loader is to allow the user to load multiple images
> or values into QEMU at startup.
>
> Memory values can be loaded like this: -device loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
>
> Images can be loaded like this: -device loader,file=./images/u-boot.elf,cpu=0
>
> This can be useful and we use it a lot in Xilinx to load multiple images
> into a machine at creation (ATF, Kernel and DTB for example).
>
> It can also be used to set registers.
>
> This patch series also make the load_elf() function more generic by not
> requiring an architecture.
Do you strongly want this in 2.6, or can we punt it to 2.7 ?
thanks
-- PMM
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v4 0/3] Add a generic loader
2016-03-16 12:03 ` [Qemu-devel] [PATCH v4 0/3] Add a generic loader Peter Maydell
@ 2016-03-16 17:18 ` Alistair Francis
2016-05-12 16:16 ` Alistair Francis
0 siblings, 1 reply; 7+ messages in thread
From: Alistair Francis @ 2016-03-16 17:18 UTC (permalink / raw)
To: Peter Maydell
Cc: Markus Armbruster, QEMU Developers, Peter Crosthwaite,
Christopher Covington, Paolo Bonzini, Andreas Färber
[-- Attachment #1: Type: text/plain, Size: 1079 bytes --]
On 16 Mar 2016 5:04 am, "Peter Maydell" <peter.maydell@linaro.org> wrote:
>
> On 3 March 2016 at 19:42, Alistair Francis <alistair.francis@xilinx.com>
wrote:
> > This work is based on the original work by Li Guang with extra
> > features added by Peter C and myself.
> >
> > The idea of this loader is to allow the user to load multiple images
> > or values into QEMU at startup.
> >
> > Memory values can be loaded like this: -device
loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
> >
> > Images can be loaded like this: -device
loader,file=./images/u-boot.elf,cpu=0
> >
> > This can be useful and we use it a lot in Xilinx to load multiple images
> > into a machine at creation (ATF, Kernel and DTB for example).
> >
> > It can also be used to set registers.
> >
> > This patch series also make the load_elf() function more generic by not
> > requiring an architecture.
>
> Do you strongly want this in 2.6, or can we punt it to 2.7 ?
It would be really nice to get it in 2.6, but it wouldn't be the end of the
world if it wasn't.
Thanks,
Alistair
>
> thanks
> -- PMM
>
[-- Attachment #2: Type: text/html, Size: 1517 bytes --]
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v4 0/3] Add a generic loader
2016-03-16 17:18 ` Alistair Francis
@ 2016-05-12 16:16 ` Alistair Francis
0 siblings, 0 replies; 7+ messages in thread
From: Alistair Francis @ 2016-05-12 16:16 UTC (permalink / raw)
To: Alistair Francis
Cc: Peter Maydell, Andreas Färber, Paolo Bonzini,
QEMU Developers, Markus Armbruster, Christopher Covington,
Peter Crosthwaite
On Wed, Mar 16, 2016 at 10:18 AM, Alistair Francis
<alistair.francis@xilinx.com> wrote:
>
> On 16 Mar 2016 5:04 am, "Peter Maydell" <peter.maydell@linaro.org> wrote:
>>
>> On 3 March 2016 at 19:42, Alistair Francis <alistair.francis@xilinx.com>
>> wrote:
>> > This work is based on the original work by Li Guang with extra
>> > features added by Peter C and myself.
>> >
>> > The idea of this loader is to allow the user to load multiple images
>> > or values into QEMU at startup.
>> >
>> > Memory values can be loaded like this: -device
>> > loader,addr=0xfd1a0104,data=0x8000000e,data-len=4
>> >
>> > Images can be loaded like this: -device
>> > loader,file=./images/u-boot.elf,cpu=0
>> >
>> > This can be useful and we use it a lot in Xilinx to load multiple images
>> > into a machine at creation (ATF, Kernel and DTB for example).
>> >
>> > It can also be used to set registers.
>> >
>> > This patch series also make the load_elf() function more generic by not
>> > requiring an architecture.
>>
>> Do you strongly want this in 2.6, or can we punt it to 2.7 ?
>
> It would be really nice to get it in 2.6, but it wouldn't be the end of the
> world if it wasn't.
I'm sending out version 5 now, hopefully this can be in for 2.7.
Thanks,
Alistair
>
> Thanks,
>
> Alistair
>
>>
>> thanks
>> -- PMM
>>
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2016-05-12 16:17 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
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2016-03-03 19:42 [Qemu-devel] [PATCH v4 0/3] Add a generic loader Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 1/3] loader: Allow ELF loader to auto-detect the ELF arch Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 2/3] generic-loader: Add a generic loader Alistair Francis
2016-03-03 19:42 ` [Qemu-devel] [PATCH v4 3/3] docs: Add a generic loader explanation document Alistair Francis
2016-03-16 12:03 ` [Qemu-devel] [PATCH v4 0/3] Add a generic loader Peter Maydell
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