11 depends on SUPPORT_SPL
14 If you want to build SPL as well as the normal image, say Y.
16 config SPL_SYS_MALLOC_SIMPLE
19 prompt "Only use malloc_simple functions in the SPL"
21 Say Y here to only use the *_simple malloc functions from
22 malloc_simple.c, rather then using the versions from dlmalloc.c;
23 this will make the SPL binary smaller at the cost of more heap
24 usage as the *_simple malloc functions do not re-use free-ed mem.
28 bool "Enable SDRAM location for SPL stack"
30 SPL starts off execution in SRAM and thus typically has only a small
31 stack available. Since SPL sets up DRAM while in its board_init_f()
32 function, it is possible for the stack to move there before
33 board_init_r() is reached. This option enables a special SDRAM
34 location for the SPL stack. U-Boot SPL switches to this after
35 board_init_f() completes, and before board_init_r() starts.
37 config SPL_STACK_R_ADDR
38 depends on SPL_STACK_R
39 hex "SDRAM location for SPL stack"
41 Specify the address in SDRAM for the SPL stack. This will be set up
42 before board_init_r() is called.
44 config SPL_STACK_R_MALLOC_SIMPLE_LEN
45 depends on SPL_STACK_R && SPL_SYS_MALLOC_SIMPLE
46 hex "Size of malloc_simple heap after switching to DRAM SPL stack"
49 Specify the amount of the stack to use as memory pool for
50 malloc_simple after switching the stack to DRAM. This may be set
51 to give board_init_r() a larger heap then the initial heap in
52 SRAM which is limited to SYS_MALLOC_F_LEN bytes.
54 config SPL_SEPARATE_BSS
56 bool "BSS section is in a different memory region from text"
58 Some platforms need a large BSS region in SPL and can provide this
59 because RAM is already set up. In this case BSS can be moved to RAM.
60 This option should then be enabled so that the correct device tree
61 location is used. Normally we put the device tree at the end of BSS
62 but with this option enabled, it goes at _image_binary_end.
66 depends on SPL && SUPPORT_TPL
69 If you want to build TPL as well as the normal image and SPL, say Y.
71 config SPL_CRC32_SUPPORT
75 Enable this to support CRC32 in FIT images within SPL. This is a
76 32-bit checksum value that can be used to verify images. This is
77 the least secure type of checksum, suitable for detected
78 accidental image corruption. For secure applications you should
79 consider SHA1 or SHA256.
81 config SPL_MD5_SUPPORT
85 Enable this to support MD5 in FIT images within SPL. An MD5
86 checksum is a 128-bit hash value used to check that the image
87 contents have not been corrupted. Note that MD5 is not considered
88 secure as it is possible (with a brute-force attack) to adjust the
89 image while still retaining the same MD5 hash value. For secure
90 applications where images may be changed maliciously, you should
91 consider SHA1 or SHA256.
93 config SPL_SHA1_SUPPORT
97 Enable this to support SHA1 in FIT images within SPL. A SHA1
98 checksum is a 160-bit (20-byte) hash value used to check that the
99 image contents have not been corrupted or maliciously altered.
100 While SHA1 is fairly secure it is coming to the end of its life
101 due to the expanding computing power avaiable to brute-force
102 attacks. For more security, consider SHA256.
104 config SPL_SHA256_SUPPORT
105 bool "Support SHA256"
108 Enable this to support SHA256 in FIT images within SPL. A SHA256
109 checksum is a 256-bit (32-byte) hash value used to check that the
110 image contents have not been corrupted. SHA256 is recommended for
111 use in secure applications since (as at 2016) there is no known
112 feasible attack that could produce a 'collision' with differing
113 input data. Use this for the highest security. Note that only the
114 SHA256 variant is supported: SHA512 and others are not currently
117 config SPL_CRYPTO_SUPPORT
118 bool "Support crypto drivers"
121 Enable crypto drivers in SPL. These drivers can be used to
122 accelerate secure boot processing in secure applications. Enable
123 this option to build the drivers in drivers/crypto as part of an
126 config SPL_HASH_SUPPORT
127 bool "Support hashing drivers"
130 Enable hashing drivers in SPL. These drivers can be used to
131 accelerate secure boot processing in secure applications. Enable
132 this option to build system-specific drivers for hash acceleration
133 as part of an SPL build.
135 config SPL_DMA_SUPPORT
136 bool "Support DMA drivers"
139 Enable DMA (direct-memory-access) drivers in SPL. These drivers
140 can be used to handle memory-to-peripheral data transfer without
141 the CPU moving the data. Enable this option to build the drivers
142 in drivers/dma as part of an SPL build.
144 config SPL_DRIVERS_MISC_SUPPORT
145 bool "Support misc drivers"
148 Enable miscellaneous drivers in SPL. These drivers perform various
149 tasks that don't fall nicely into other categories, Enable this
150 option to build the drivers in drivers/misc as part of an SPL
151 build, for those that support building in SPL (not all drivers do).
153 config SPL_ENV_SUPPORT
154 bool "Support an environment"
157 Enable environment support in SPL. The U-Boot environment provides
158 a number of settings (essentially name/value pairs) which can
159 control many aspects of U-Boot's operation. Normally this is not
160 needed in SPL as it has a much simpler task with less
161 configuration. But some boards use this to support 'Falcon' boot
162 on EXT2 and FAT, where SPL boots directly into Linux without
163 starting U-Boot first. Enabling this option will make getenv()
164 and setenv() available in SPL.
166 config SPL_ETH_SUPPORT
167 bool "Support Ethernet"
168 depends on SPL_ENV_SUPPORT
170 Enable access to the network subsystem and associated Ethernet
171 drivers in SPL. This permits SPL to load U-Boot over an Ethernet
172 link rather than from an on-board peripheral. Environment support
173 is required since the network stack uses a number of environment
174 variables. See also SPL_NET_SUPPORT.
176 config SPL_EXT_SUPPORT
177 bool "Support EXT filesystems"
180 Enable support for EXT2/3/4 filesystems with SPL. This permits
181 U-Boot (or Linux in Falcon mode) to be loaded from an EXT
182 filesystem from within SPL. Support for the underlying block
183 device (e.g. MMC or USB) must be enabled separately.
185 config SPL_FAT_SUPPORT
186 bool "Support FAT filesystems"
189 Enable support for FAT and VFAT filesystems with SPL. This
190 permits U-Boot (or Linux in Falcon mode) to be loaded from a FAT
191 filesystem from within SPL. Support for the underlying block
192 device (e.g. MMC or USB) must be enabled separately.
194 config SPL_FPGA_SUPPORT
198 Enable support for FPGAs in SPL. Field-programmable Gate Arrays
199 provide software-configurable hardware which is typically used to
200 implement peripherals (such as UARTs, LCD displays, MMC) or
201 accelerate custom processing functions, such as image processing
202 or machine learning. Sometimes it is useful to program the FPGA
203 as early as possible during boot, and this option can enable that
206 config SPL_GPIO_SUPPORT
210 Enable support for GPIOs (General-purpose Input/Output) in SPL.
211 GPIOs allow U-Boot to read the state of an input line (high or
212 low) and set the state of an output line. This can be used to
213 drive LEDs, control power to various system parts and read user
214 input. GPIOs can be useful in SPL to enable a 'sign-of-life' LED,
215 for example. Enable this option to build the drivers in
216 drivers/gpio as part of an SPL build.
218 config SPL_I2C_SUPPORT
222 Enable support for the I2C (Inter-Integrated Circuit) bus in SPL.
223 I2C works with a clock and data line which can be driven by a
224 one or more masters or slaves. It is a fairly complex bus but is
225 widely used as it only needs two lines for communication. Speeds of
226 400kbps are typical but up to 3.4Mbps is supported by some
227 hardware. I2C can be useful in SPL to configure power management
228 ICs (PMICs) before raising the CPU clock speed, for example.
229 Enable this option to build the drivers in drivers/i2c as part of
232 config SPL_LIBCOMMON_SUPPORT
233 bool "Support common libraries"
236 Enable support for common U-Boot libraries within SPL. These
237 libraries include common code to deal with U-Boot images,
238 environment and USB, for example. This option is enabled on many
239 boards. Enable this option to build the code in common/ as part of
242 config SPL_LIBDISK_SUPPORT
243 bool "Support disk paritions"
246 Enable support for disk partitions within SPL. 'Disk' is something
247 of a misnomer as it includes non-spinning media such as flash (as
248 used in MMC and USB sticks). Partitions provide a way for a disk
249 to be split up into separate regions, with a partition table placed
250 at the start or end which describes the location and size of each
251 'partition'. These partitions are typically uses as individual block
252 devices, typically with an EXT2 or FAT filesystem in each. This
253 option enables whatever partition support has been enabled in
254 U-Boot to also be used in SPL. It brings in the code in disk/.
256 config SPL_LIBGENERIC_SUPPORT
257 bool "Support generic libraries"
260 Enable support for generic U-Boot libraries within SPL. These
261 libraries include generic code to deal with device tree, hashing,
262 printf(), compression and the like. This option is enabled on many
263 boards. Enable this option to build the code in lib/ as part of an
266 config SPL_MMC_SUPPORT
270 Enable support for MMC (Multimedia Card) within SPL. This enables
271 the MMC protocol implementation and allows any enabled drivers to
272 be used within SPL. MMC can be used with or without disk partition
273 support depending on the application (SPL_LIBDISK_SUPPORT). Enable
274 this option to build the drivers in drivers/mmc as part of an SPL
277 config SPL_MPC8XXX_INIT_DDR_SUPPORT
278 bool "Support MPC8XXX DDR init"
281 Enable support for DDR-SDRAM (double-data-rate synchronous dynamic
282 random-access memory) on the MPC8XXX family within SPL. This
283 allows DRAM to be set up before loading U-Boot into that DRAM,
286 config SPL_MTD_SUPPORT
287 bool "Support MTD drivers"
290 Enable support for MTD (Memory Technology Device) within SPL. MTD
291 provides a block interface over raw NAND and can also be used with
292 SPI flash. This allows SPL to load U-Boot from supported MTD
293 devices. See SPL_NAND_SUPPORT and SPL_ONENAND_SUPPORT for how
294 to enable specific MTD drivers.
296 config SPL_MUSB_NEW_SUPPORT
297 bool "Support new Mentor Graphics USB"
300 Enable support for Mentor Graphics USB in SPL. This is a new
301 driver used by some boards. Enable this option to build
302 the drivers in drivers/usb/musb-new as part of an SPL build. The
303 old drivers are in drivers/usb/musb.
305 config SPL_NAND_SUPPORT
306 bool "Support NAND flash"
309 Enable support for NAND (Negative AND) flash in SPL. NAND flash
310 can be used to allow SPL to load U-Boot from supported devices.
311 This enables the drivers in drivers/mtd/nand as part of an SPL
314 config SPL_NET_SUPPORT
315 bool "Support networking"
318 Enable support for network devices (such as Ethernet) in SPL.
319 This permits SPL to load U-Boot over a network link rather than
320 from an on-board peripheral. Environment support is required since
321 the network stack uses a number of environment variables. See also
325 config SPL_NET_VCI_STRING
326 string "BOOTP Vendor Class Identifier string sent by SPL"
328 As defined by RFC 2132 the vendor class identifier field can be
329 sent by the client to identify the vendor type and configuration
330 of a client. This is often used in practice to allow for the DHCP
331 server to specify different files to load depending on if the ROM,
332 SPL or U-Boot itself makes the request
333 endif # if SPL_NET_SUPPORT
335 config SPL_NO_CPU_SUPPORT
336 bool "Drop CPU code in SPL"
339 This is specific to the ARM926EJ-S CPU. It disables the standard
340 start.S start-up code, presumably so that a replacement can be
341 used on that CPU. You should not enable it unless you know what
344 config SPL_NOR_SUPPORT
345 bool "Support NOR flash"
348 Enable support for loading U-Boot from memory-mapped NOR (Negative
349 OR) flash in SPL. NOR flash is slow to write but fast to read, and
350 a memory-mapped device makes it very easy to access. Loading from
351 NOR is typically achieved with just a memcpy().
353 config SPL_ONENAND_SUPPORT
354 bool "Support OneNAND flash"
357 Enable support for OneNAND (Negative AND) flash in SPL. OneNAND is
358 a type of NAND flash and therefore can be used to allow SPL to
359 load U-Boot from supported devices. This enables the drivers in
360 drivers/mtd/onenand as part of an SPL build.
362 config SPL_POST_MEM_SUPPORT
363 bool "Support POST drivers"
366 Enable support for POST (Power-on Self Test) in SPL. POST is a
367 procedure that checks that the hardware (CPU or board) appears to
368 be functionally correctly. It is a sanity check that can be
369 performed before booting. This enables the drivers in post/drivers
370 as part of an SPL build.
372 config SPL_POWER_SUPPORT
373 bool "Support power drivers"
376 Enable support for power control in SPL. This includes support
377 for PMICs (Power-management Integrated Circuits) and some of the
378 features provided by PMICs. In particular, voltage regulators can
379 be used to enable/disable power and vary its voltage. That can be
380 useful in SPL to turn on boot peripherals and adjust CPU voltage
381 so that the clock speed can be increased. This enables the drivers
382 in drivers/power, drivers/power/pmic and drivers/power/regulator
383 as part of an SPL build.
385 config SPL_SATA_SUPPORT
386 bool "Support loading from SATA"
389 Enable support for SATA (Serial AT attachment) in SPL. This allows
390 use of SATA devices such as hard drives and flash drivers for
391 loading U-Boot. SATA is used in higher-end embedded systems and
392 can provide higher performance than MMC , at somewhat higher
393 expense and power consumption. This enables loading from SATA
394 using a configured device.
396 config SPL_SERIAL_SUPPORT
397 bool "Support serial"
400 Enable support for serial in SPL. This allows use of a serial UART
401 for displaying messages while SPL is running. It also brings in
402 printf() and panic() functions. This should normally be enabled
403 unless there are space reasons not to. Even then, consider
404 enabling USE_TINY_PRINTF which is a small printf() version.
406 config SPL_SPI_FLASH_SUPPORT
407 bool "Support SPI flash drivers"
410 Enable support for using SPI flash in SPL, and loading U-Boot from
411 SPI flash. SPI flash (Serial Peripheral Bus flash) is named after
412 the SPI bus that is used to connect it to a system. It is a simple
413 but fast bidirectional 4-wire bus (clock, chip select and two data
414 lines). This enables the drivers in drivers/mtd/spi as part of an
415 SPL build. This normally requires SPL_SPI_SUPPORT.
417 config SPL_SPI_SUPPORT
418 bool "Support SPI drivers"
421 Enable support for using SPI in SPL. This is used for connecting
422 to SPI flash for loading U-Boot. See SPL_SPI_FLASH_SUPPORT for
423 more details on that. The SPI driver provides the transport for
424 data between the SPI flash and the CPU. This option can be used to
425 enable SPI drivers that are needed for other purposes also, such
428 config SPL_USBETH_SUPPORT
429 bool "Support USB Ethernet drivers"
432 Enable access to the USB network subsystem and associated
433 drivers in SPL. This permits SPL to load U-Boot over a
434 USB-connected Ethernet link (such as a USB Ethernet dongle) rather
435 than from an onboard peripheral. Environment support is required
436 since the network stack uses a number of environment variables.
437 See also SPL_NET_SUPPORT and SPL_ETH_SUPPORT.
439 config SPL_USB_HOST_SUPPORT
440 bool "Support USB host drivers"
443 Enable access to USB (Universal Serial Bus) host devices so that
444 SPL can load U-Boot from a connected USB peripheral, such as a USB
445 flash stick. While USB takes a little longer to start up than most
446 buses, it is very flexible since many different types of storage
447 device can be attached. This option enables the drivers in
448 drivers/usb/host as part of an SPL build.
450 config SPL_USB_SUPPORT
451 bool "Support loading from USB"
452 depends on SPL_USB_HOST_SUPPORT
454 Enable support for USB devices in SPL. This allows use of USB
455 devices such as hard drives and flash drivers for loading U-Boot.
456 The actual drivers are enabled separately using the normal U-Boot
457 config options. This enables loading from USB using a configured
460 config SPL_WATCHDOG_SUPPORT
461 bool "Support watchdog drivers"
464 Enable support for watchdog drivers in SPL. A watchdog is
465 typically a hardware peripheral which can reset the system when it
466 detects no activity for a while (such as a software crash). This
467 enables the drivers in drivers/watchdog as part of an SPL build.
469 config SPL_YMODEM_SUPPORT
470 bool "Support loading using Ymodem"
473 While loading from serial is slow it can be a useful backup when
474 there is no other option. The Ymodem protocol provides a reliable
475 means of transmitting U-Boot over a serial line for using in SPL,
476 with a checksum to ensure correctness.
478 config TPL_ENV_SUPPORT
479 bool "Support an environment"
482 Enable environment support in TPL. See SPL_ENV_SUPPORT for details.
484 config TPL_I2C_SUPPORT
488 Enable support for the I2C bus in SPL. See SPL_I2C_SUPPORT for
491 config TPL_LIBCOMMON_SUPPORT
492 bool "Support common libraries"
495 Enable support for common U-Boot libraries within TPL. See
496 SPL_LIBCOMMON_SUPPORT for details.
498 config TPL_LIBGENERIC_SUPPORT
499 bool "Support generic libraries"
502 Enable support for generic U-Boot libraries within TPL. See
503 SPL_LIBGENERIC_SUPPORT for details.
505 config TPL_MPC8XXX_INIT_DDR_SUPPORT
506 bool "Support MPC8XXX DDR init"
509 Enable support for DDR-SDRAM on the MPC8XXX family within TPL. See
510 SPL_MPC8XXX_INIT_DDR_SUPPORT for details.
512 config TPL_MMC_SUPPORT
516 Enable support for MMC within TPL. See SPL_MMC_SUPPORT for details.
518 config TPL_NAND_SUPPORT
519 bool "Support NAND flash"
522 Enable support for NAND in SPL. See SPL_NAND_SUPPORT for details.
524 config TPL_SERIAL_SUPPORT
525 bool "Support serial"
528 Enable support for serial in SPL. See SPL_SERIAL_SUPPORT for
531 config TPL_SPI_FLASH_SUPPORT
532 bool "Support SPI flash drivers"
535 Enable support for using SPI flash in SPL. See SPL_SPI_FLASH_SUPPORT
538 config TPL_SPI_SUPPORT
539 bool "Support SPI drivers"
542 Enable support for using SPI in SPL. See SPL_SPI_SUPPORT for