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.
64 config SPL_DISPLAY_PRINT
66 bool "Display a board-specific message in SPL"
68 If this option is enabled, U-Boot will call the function
69 spl_display_print() immediately after displaying the SPL console
70 banner ("U-Boot SPL ..."). This function should be provided by
75 depends on SPL && SUPPORT_TPL
78 If you want to build TPL as well as the normal image and SPL, say Y.
80 config SPL_CRC32_SUPPORT
84 Enable this to support CRC32 in FIT images within SPL. This is a
85 32-bit checksum value that can be used to verify images. This is
86 the least secure type of checksum, suitable for detected
87 accidental image corruption. For secure applications you should
88 consider SHA1 or SHA256.
90 config SPL_MD5_SUPPORT
94 Enable this to support MD5 in FIT images within SPL. An MD5
95 checksum is a 128-bit hash value used to check that the image
96 contents have not been corrupted. Note that MD5 is not considered
97 secure as it is possible (with a brute-force attack) to adjust the
98 image while still retaining the same MD5 hash value. For secure
99 applications where images may be changed maliciously, you should
100 consider SHA1 or SHA256.
102 config SPL_SHA1_SUPPORT
106 Enable this to support SHA1 in FIT images within SPL. A SHA1
107 checksum is a 160-bit (20-byte) hash value used to check that the
108 image contents have not been corrupted or maliciously altered.
109 While SHA1 is fairly secure it is coming to the end of its life
110 due to the expanding computing power avaiable to brute-force
111 attacks. For more security, consider SHA256.
113 config SPL_SHA256_SUPPORT
114 bool "Support SHA256"
117 Enable this to support SHA256 in FIT images within SPL. A SHA256
118 checksum is a 256-bit (32-byte) hash value used to check that the
119 image contents have not been corrupted. SHA256 is recommended for
120 use in secure applications since (as at 2016) there is no known
121 feasible attack that could produce a 'collision' with differing
122 input data. Use this for the highest security. Note that only the
123 SHA256 variant is supported: SHA512 and others are not currently
126 config SPL_CRYPTO_SUPPORT
127 bool "Support crypto drivers"
130 Enable crypto drivers in SPL. These drivers can be used to
131 accelerate secure boot processing in secure applications. Enable
132 this option to build the drivers in drivers/crypto as part of an
135 config SPL_HASH_SUPPORT
136 bool "Support hashing drivers"
139 Enable hashing drivers in SPL. These drivers can be used to
140 accelerate secure boot processing in secure applications. Enable
141 this option to build system-specific drivers for hash acceleration
142 as part of an SPL build.
144 config SPL_DMA_SUPPORT
145 bool "Support DMA drivers"
148 Enable DMA (direct-memory-access) drivers in SPL. These drivers
149 can be used to handle memory-to-peripheral data transfer without
150 the CPU moving the data. Enable this option to build the drivers
151 in drivers/dma as part of an SPL build.
153 config SPL_DRIVERS_MISC_SUPPORT
154 bool "Support misc drivers"
157 Enable miscellaneous drivers in SPL. These drivers perform various
158 tasks that don't fall nicely into other categories, Enable this
159 option to build the drivers in drivers/misc as part of an SPL
160 build, for those that support building in SPL (not all drivers do).
162 config SPL_ENV_SUPPORT
163 bool "Support an environment"
166 Enable environment support in SPL. The U-Boot environment provides
167 a number of settings (essentially name/value pairs) which can
168 control many aspects of U-Boot's operation. Normally this is not
169 needed in SPL as it has a much simpler task with less
170 configuration. But some boards use this to support 'Falcon' boot
171 on EXT2 and FAT, where SPL boots directly into Linux without
172 starting U-Boot first. Enabling this option will make getenv()
173 and setenv() available in SPL.
175 config SPL_ETH_SUPPORT
176 bool "Support Ethernet"
177 depends on SPL_ENV_SUPPORT
179 Enable access to the network subsystem and associated Ethernet
180 drivers in SPL. This permits SPL to load U-Boot over an Ethernet
181 link rather than from an on-board peripheral. Environment support
182 is required since the network stack uses a number of environment
183 variables. See also SPL_NET_SUPPORT.
185 config SPL_EXT_SUPPORT
186 bool "Support EXT filesystems"
189 Enable support for EXT2/3/4 filesystems with SPL. This permits
190 U-Boot (or Linux in Falcon mode) to be loaded from an EXT
191 filesystem from within SPL. Support for the underlying block
192 device (e.g. MMC or USB) must be enabled separately.
194 config SPL_FAT_SUPPORT
195 bool "Support FAT filesystems"
198 Enable support for FAT and VFAT filesystems with SPL. This
199 permits U-Boot (or Linux in Falcon mode) to be loaded from a FAT
200 filesystem from within SPL. Support for the underlying block
201 device (e.g. MMC or USB) must be enabled separately.
203 config SPL_FPGA_SUPPORT
207 Enable support for FPGAs in SPL. Field-programmable Gate Arrays
208 provide software-configurable hardware which is typically used to
209 implement peripherals (such as UARTs, LCD displays, MMC) or
210 accelerate custom processing functions, such as image processing
211 or machine learning. Sometimes it is useful to program the FPGA
212 as early as possible during boot, and this option can enable that
215 config SPL_GPIO_SUPPORT
219 Enable support for GPIOs (General-purpose Input/Output) in SPL.
220 GPIOs allow U-Boot to read the state of an input line (high or
221 low) and set the state of an output line. This can be used to
222 drive LEDs, control power to various system parts and read user
223 input. GPIOs can be useful in SPL to enable a 'sign-of-life' LED,
224 for example. Enable this option to build the drivers in
225 drivers/gpio as part of an SPL build.
227 config SPL_I2C_SUPPORT
231 Enable support for the I2C (Inter-Integrated Circuit) bus in SPL.
232 I2C works with a clock and data line which can be driven by a
233 one or more masters or slaves. It is a fairly complex bus but is
234 widely used as it only needs two lines for communication. Speeds of
235 400kbps are typical but up to 3.4Mbps is supported by some
236 hardware. I2C can be useful in SPL to configure power management
237 ICs (PMICs) before raising the CPU clock speed, for example.
238 Enable this option to build the drivers in drivers/i2c as part of
241 config SPL_LIBCOMMON_SUPPORT
242 bool "Support common libraries"
245 Enable support for common U-Boot libraries within SPL. These
246 libraries include common code to deal with U-Boot images,
247 environment and USB, for example. This option is enabled on many
248 boards. Enable this option to build the code in common/ as part of
251 config SPL_LIBDISK_SUPPORT
252 bool "Support disk paritions"
255 Enable support for disk partitions within SPL. 'Disk' is something
256 of a misnomer as it includes non-spinning media such as flash (as
257 used in MMC and USB sticks). Partitions provide a way for a disk
258 to be split up into separate regions, with a partition table placed
259 at the start or end which describes the location and size of each
260 'partition'. These partitions are typically uses as individual block
261 devices, typically with an EXT2 or FAT filesystem in each. This
262 option enables whatever partition support has been enabled in
263 U-Boot to also be used in SPL. It brings in the code in disk/.
265 config SPL_LIBGENERIC_SUPPORT
266 bool "Support generic libraries"
269 Enable support for generic U-Boot libraries within SPL. These
270 libraries include generic code to deal with device tree, hashing,
271 printf(), compression and the like. This option is enabled on many
272 boards. Enable this option to build the code in lib/ as part of an
275 config SPL_MMC_SUPPORT
279 Enable support for MMC (Multimedia Card) within SPL. This enables
280 the MMC protocol implementation and allows any enabled drivers to
281 be used within SPL. MMC can be used with or without disk partition
282 support depending on the application (SPL_LIBDISK_SUPPORT). Enable
283 this option to build the drivers in drivers/mmc as part of an SPL
286 config SPL_MPC8XXX_INIT_DDR_SUPPORT
287 bool "Support MPC8XXX DDR init"
290 Enable support for DDR-SDRAM (double-data-rate synchronous dynamic
291 random-access memory) on the MPC8XXX family within SPL. This
292 allows DRAM to be set up before loading U-Boot into that DRAM,
295 config SPL_MTD_SUPPORT
296 bool "Support MTD drivers"
299 Enable support for MTD (Memory Technology Device) within SPL. MTD
300 provides a block interface over raw NAND and can also be used with
301 SPI flash. This allows SPL to load U-Boot from supported MTD
302 devices. See SPL_NAND_SUPPORT and SPL_ONENAND_SUPPORT for how
303 to enable specific MTD drivers.
305 config SPL_MUSB_NEW_SUPPORT
306 bool "Support new Mentor Graphics USB"
309 Enable support for Mentor Graphics USB in SPL. This is a new
310 driver used by some boards. Enable this option to build
311 the drivers in drivers/usb/musb-new as part of an SPL build. The
312 old drivers are in drivers/usb/musb.
314 config SPL_NAND_SUPPORT
315 bool "Support NAND flash"
318 Enable support for NAND (Negative AND) flash in SPL. NAND flash
319 can be used to allow SPL to load U-Boot from supported devices.
320 This enables the drivers in drivers/mtd/nand as part of an SPL
323 config SPL_NET_SUPPORT
324 bool "Support networking"
327 Enable support for network devices (such as Ethernet) in SPL.
328 This permits SPL to load U-Boot over a network link rather than
329 from an on-board peripheral. Environment support is required since
330 the network stack uses a number of environment variables. See also
334 config SPL_NET_VCI_STRING
335 string "BOOTP Vendor Class Identifier string sent by SPL"
337 As defined by RFC 2132 the vendor class identifier field can be
338 sent by the client to identify the vendor type and configuration
339 of a client. This is often used in practice to allow for the DHCP
340 server to specify different files to load depending on if the ROM,
341 SPL or U-Boot itself makes the request
342 endif # if SPL_NET_SUPPORT
344 config SPL_NO_CPU_SUPPORT
345 bool "Drop CPU code in SPL"
348 This is specific to the ARM926EJ-S CPU. It disables the standard
349 start.S start-up code, presumably so that a replacement can be
350 used on that CPU. You should not enable it unless you know what
353 config SPL_NOR_SUPPORT
354 bool "Support NOR flash"
357 Enable support for loading U-Boot from memory-mapped NOR (Negative
358 OR) flash in SPL. NOR flash is slow to write but fast to read, and
359 a memory-mapped device makes it very easy to access. Loading from
360 NOR is typically achieved with just a memcpy().
362 config SPL_ONENAND_SUPPORT
363 bool "Support OneNAND flash"
366 Enable support for OneNAND (Negative AND) flash in SPL. OneNAND is
367 a type of NAND flash and therefore can be used to allow SPL to
368 load U-Boot from supported devices. This enables the drivers in
369 drivers/mtd/onenand as part of an SPL build.
371 config SPL_POST_MEM_SUPPORT
372 bool "Support POST drivers"
375 Enable support for POST (Power-on Self Test) in SPL. POST is a
376 procedure that checks that the hardware (CPU or board) appears to
377 be functionally correctly. It is a sanity check that can be
378 performed before booting. This enables the drivers in post/drivers
379 as part of an SPL build.
381 config SPL_POWER_SUPPORT
382 bool "Support power drivers"
385 Enable support for power control in SPL. This includes support
386 for PMICs (Power-management Integrated Circuits) and some of the
387 features provided by PMICs. In particular, voltage regulators can
388 be used to enable/disable power and vary its voltage. That can be
389 useful in SPL to turn on boot peripherals and adjust CPU voltage
390 so that the clock speed can be increased. This enables the drivers
391 in drivers/power, drivers/power/pmic and drivers/power/regulator
392 as part of an SPL build.
394 config SPL_SATA_SUPPORT
395 bool "Support loading from SATA"
398 Enable support for SATA (Serial AT attachment) in SPL. This allows
399 use of SATA devices such as hard drives and flash drivers for
400 loading U-Boot. SATA is used in higher-end embedded systems and
401 can provide higher performance than MMC , at somewhat higher
402 expense and power consumption. This enables loading from SATA
403 using a configured device.
405 config SPL_SERIAL_SUPPORT
406 bool "Support serial"
409 Enable support for serial in SPL. This allows use of a serial UART
410 for displaying messages while SPL is running. It also brings in
411 printf() and panic() functions. This should normally be enabled
412 unless there are space reasons not to. Even then, consider
413 enabling USE_TINY_PRINTF which is a small printf() version.
415 config SPL_SPI_FLASH_SUPPORT
416 bool "Support SPI flash drivers"
419 Enable support for using SPI flash in SPL, and loading U-Boot from
420 SPI flash. SPI flash (Serial Peripheral Bus flash) is named after
421 the SPI bus that is used to connect it to a system. It is a simple
422 but fast bidirectional 4-wire bus (clock, chip select and two data
423 lines). This enables the drivers in drivers/mtd/spi as part of an
424 SPL build. This normally requires SPL_SPI_SUPPORT.
426 config SPL_SPI_SUPPORT
427 bool "Support SPI drivers"
430 Enable support for using SPI in SPL. This is used for connecting
431 to SPI flash for loading U-Boot. See SPL_SPI_FLASH_SUPPORT for
432 more details on that. The SPI driver provides the transport for
433 data between the SPI flash and the CPU. This option can be used to
434 enable SPI drivers that are needed for other purposes also, such
437 config SPL_USBETH_SUPPORT
438 bool "Support USB Ethernet drivers"
441 Enable access to the USB network subsystem and associated
442 drivers in SPL. This permits SPL to load U-Boot over a
443 USB-connected Ethernet link (such as a USB Ethernet dongle) rather
444 than from an onboard peripheral. Environment support is required
445 since the network stack uses a number of environment variables.
446 See also SPL_NET_SUPPORT and SPL_ETH_SUPPORT.
448 config SPL_USB_HOST_SUPPORT
449 bool "Support USB host drivers"
452 Enable access to USB (Universal Serial Bus) host devices so that
453 SPL can load U-Boot from a connected USB peripheral, such as a USB
454 flash stick. While USB takes a little longer to start up than most
455 buses, it is very flexible since many different types of storage
456 device can be attached. This option enables the drivers in
457 drivers/usb/host as part of an SPL build.
459 config SPL_USB_SUPPORT
460 bool "Support loading from USB"
461 depends on SPL_USB_HOST_SUPPORT
463 Enable support for USB devices in SPL. This allows use of USB
464 devices such as hard drives and flash drivers for loading U-Boot.
465 The actual drivers are enabled separately using the normal U-Boot
466 config options. This enables loading from USB using a configured
469 config SPL_WATCHDOG_SUPPORT
470 bool "Support watchdog drivers"
473 Enable support for watchdog drivers in SPL. A watchdog is
474 typically a hardware peripheral which can reset the system when it
475 detects no activity for a while (such as a software crash). This
476 enables the drivers in drivers/watchdog as part of an SPL build.
478 config SPL_YMODEM_SUPPORT
479 bool "Support loading using Ymodem"
482 While loading from serial is slow it can be a useful backup when
483 there is no other option. The Ymodem protocol provides a reliable
484 means of transmitting U-Boot over a serial line for using in SPL,
485 with a checksum to ensure correctness.
487 config TPL_ENV_SUPPORT
488 bool "Support an environment"
491 Enable environment support in TPL. See SPL_ENV_SUPPORT for details.
493 config TPL_I2C_SUPPORT
497 Enable support for the I2C bus in SPL. See SPL_I2C_SUPPORT for
500 config TPL_LIBCOMMON_SUPPORT
501 bool "Support common libraries"
504 Enable support for common U-Boot libraries within TPL. See
505 SPL_LIBCOMMON_SUPPORT for details.
507 config TPL_LIBGENERIC_SUPPORT
508 bool "Support generic libraries"
511 Enable support for generic U-Boot libraries within TPL. See
512 SPL_LIBGENERIC_SUPPORT for details.
514 config TPL_MPC8XXX_INIT_DDR_SUPPORT
515 bool "Support MPC8XXX DDR init"
518 Enable support for DDR-SDRAM on the MPC8XXX family within TPL. See
519 SPL_MPC8XXX_INIT_DDR_SUPPORT for details.
521 config TPL_MMC_SUPPORT
525 Enable support for MMC within TPL. See SPL_MMC_SUPPORT for details.
527 config TPL_NAND_SUPPORT
528 bool "Support NAND flash"
531 Enable support for NAND in SPL. See SPL_NAND_SUPPORT for details.
533 config TPL_SERIAL_SUPPORT
534 bool "Support serial"
537 Enable support for serial in SPL. See SPL_SERIAL_SUPPORT for
540 config TPL_SPI_FLASH_SUPPORT
541 bool "Support SPI flash drivers"
544 Enable support for using SPI flash in SPL. See SPL_SPI_FLASH_SUPPORT
547 config TPL_SPI_SUPPORT
548 bool "Support SPI drivers"
551 Enable support for using SPI in SPL. See SPL_SPI_SUPPORT for