mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-01 17:10:11 +00:00
19e99fb4ff
Allwinner devices support SPI flash as one of the possible
bootable media type. The SPI flash chip needs to be connected
to SPI0 pins (port C) to make this work. More information is
available at:
https://linux-sunxi.org/Bootable_SPI_flash
This patch adds the initial support for booting from SPI flash.
The existing SPI frameworks are not used in order to reduce the
SPL code size. Right now the SPL size grows by ~370 bytes when
CONFIG_SPL_SPI_SUNXI option is enabled.
While there are no popular Allwinner devices with SPI flash at
the moment, testing can be done using a SPI flash module (it
can be bought for ~2$ on ebay) and jumper wires with the boards,
which expose relevant pins on the expansion header. The SPI flash
chips themselves are very cheap (some prices are even listed as
low as 4 cents) and should not cost much if somebody decides to
design a development board with an SPI flash chip soldered on
the PCB.
Another nice feature of the SPI flash is that it can be safely
accessed in a device-independent way (since we know that the
boot ROM is already probing these pins during the boot time).
And if, for example, Olimex boards opted to use SPI flash instead
of EEPROM, then they would have been able to have U-Boot installed
in the SPI flash now and boot the rest of the system from the SATA
hard drive. Hopefully we may see new interesting Allwinner based
development boards in the future, now that the software support
for the SPI flash is in a better shape :-)
Testing can be done by enabling the CONFIG_SPL_SPI_SUNXI option
in a board defconfig, then building U-Boot and finally flashing
the resulting u-boot-sunxi-with-spl.bin binary over USB OTG with
a help of the sunxi-fel tool:
sunxi-fel spiflash-write 0 u-boot-sunxi-with-spl.bin
The device needs to be switched into FEL (USB recovery) mode first.
The most suitable boards for testing are Orange Pi PC and Pine64.
Because these boards are cheap, have no built-in NAND/eMMC and
expose SPI0 pins on the Raspberry Pi compatible expansion header.
The A13-OLinuXino-Micro board also can be used.
Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
143 lines
4.6 KiB
Text
143 lines
4.6 KiB
Text
menu "SPI Flash Support"
|
||
|
||
config DM_SPI_FLASH
|
||
bool "Enable Driver Model for SPI flash"
|
||
depends on DM && DM_SPI
|
||
help
|
||
Enable driver model for SPI flash. This SPI flash interface
|
||
(spi_flash_probe(), spi_flash_write(), etc.) is then
|
||
implemented by the SPI flash uclass. There is one standard
|
||
SPI flash driver which knows how to probe most chips
|
||
supported by U-Boot. The uclass interface is defined in
|
||
include/spi_flash.h, but is currently fully compatible
|
||
with the old interface to avoid confusion and duplication
|
||
during the transition parent. SPI and SPI flash must be
|
||
enabled together (it is not possible to use driver model
|
||
for one and not the other).
|
||
|
||
config SPI_FLASH_SANDBOX
|
||
bool "Support sandbox SPI flash device"
|
||
depends on SANDBOX && DM_SPI_FLASH
|
||
help
|
||
Since sandbox cannot access real devices, an emulation mechanism is
|
||
provided instead. Drivers can be connected up to the sandbox SPI
|
||
bus (see CONFIG_SANDBOX_SPI) and SPI traffic will be routed to this
|
||
device. Typically the contents of the emulated SPI flash device is
|
||
stored in a file on the host filesystem.
|
||
|
||
config SPI_FLASH
|
||
bool "Legacy SPI Flash Interface support"
|
||
help
|
||
Enable the legacy SPI flash support. This will include basic
|
||
standard support for things like probing, read / write, and
|
||
erasing through cmd_sf interface.
|
||
|
||
If unsure, say N
|
||
|
||
config SPI_FLASH_BAR
|
||
bool "SPI flash Bank/Extended address register support"
|
||
depends on SPI_FLASH
|
||
help
|
||
Enable the SPI flash Bank/Extended address register support.
|
||
Bank/Extended address registers are used to access the flash
|
||
which has size > 16MiB in 3-byte addressing.
|
||
|
||
if SPI_FLASH
|
||
|
||
config SPI_FLASH_ATMEL
|
||
bool "Atmel SPI flash support"
|
||
help
|
||
Add support for various Atmel SPI flash chips (AT45xxx and AT25xxx)
|
||
|
||
config SPI_FLASH_EON
|
||
bool "EON SPI flash support"
|
||
help
|
||
Add support for various EON SPI flash chips (EN25xxx)
|
||
|
||
config SPI_FLASH_GIGADEVICE
|
||
bool "GigaDevice SPI flash support"
|
||
help
|
||
Add support for various GigaDevice SPI flash chips (GD25xxx)
|
||
|
||
config SPI_FLASH_MACRONIX
|
||
bool "Macronix SPI flash support"
|
||
help
|
||
Add support for various Macronix SPI flash chips (MX25Lxxx)
|
||
|
||
config SPI_FLASH_SPANSION
|
||
bool "Spansion SPI flash support"
|
||
help
|
||
Add support for various Spansion SPI flash chips (S25FLxxx)
|
||
|
||
config SPI_FLASH_STMICRO
|
||
bool "STMicro SPI flash support"
|
||
help
|
||
Add support for various STMicro SPI flash chips (M25Pxxx and N25Qxxx)
|
||
|
||
config SPI_FLASH_SST
|
||
bool "SST SPI flash support"
|
||
help
|
||
Add support for various SST SPI flash chips (SST25xxx)
|
||
|
||
config SPI_FLASH_WINBOND
|
||
bool "Winbond SPI flash support"
|
||
help
|
||
Add support for various Winbond SPI flash chips (W25xxx)
|
||
|
||
endif
|
||
|
||
config SPI_FLASH_USE_4K_SECTORS
|
||
bool "Use small 4096 B erase sectors"
|
||
depends on SPI_FLASH
|
||
default y
|
||
help
|
||
Many flash memories support erasing small (4096 B) sectors. Depending
|
||
on the usage this feature may provide performance gain in comparison
|
||
to erasing whole blocks (32/64 KiB).
|
||
Changing a small part of the flash's contents is usually faster with
|
||
small sectors. On the other hand erasing should be faster when using
|
||
64 KiB block instead of 16 × 4 KiB sectors.
|
||
|
||
Please note that some tools/drivers/filesystems may not work with
|
||
4096 B erase size (e.g. UBIFS requires 15 KiB as a minimum).
|
||
|
||
config SPI_FLASH_DATAFLASH
|
||
bool "AT45xxx DataFlash support"
|
||
depends on SPI_FLASH && DM_SPI_FLASH
|
||
help
|
||
Enable the access for SPI-flash-based AT45xxx DataFlash chips.
|
||
DataFlash is a kind of SPI flash. Most AT45 chips have two buffers
|
||
in each chip, which may be used for double buffered I/O; but this
|
||
driver doesn't (yet) use these for any kind of i/o overlap or prefetching.
|
||
|
||
Sometimes DataFlash is packaged in MMC-format cards, although the
|
||
MMC stack can't (yet?) distinguish between MMC and DataFlash
|
||
protocols during enumeration.
|
||
|
||
If unsure, say N
|
||
|
||
config SPI_FLASH_MTD
|
||
bool "SPI Flash MTD support"
|
||
depends on SPI_FLASH
|
||
help
|
||
Enable the MTD support for spi flash layer, this adapter is for
|
||
translating mtd_read/mtd_write commands into spi_flash_read/write
|
||
commands. It is not intended to use it within sf_cmd or the SPI
|
||
flash subsystem. Such an adapter is needed for subsystems like
|
||
UBI which can only operate on top of the MTD layer.
|
||
|
||
If unsure, say N
|
||
|
||
if SPL
|
||
|
||
config SPL_SPI_SUNXI
|
||
bool "Support for SPI Flash on Allwinner SoCs in SPL"
|
||
depends on MACH_SUN4I || MACH_SUN5I || MACH_SUN7I || MACH_SUN8I_H3 || MACH_SUN50I
|
||
---help---
|
||
Enable support for SPI Flash. This option allows SPL to read from
|
||
sunxi SPI Flash. It uses the same method as the boot ROM, so does
|
||
not need any extra configuration.
|
||
|
||
endif
|
||
|
||
endmenu # menu "SPI Flash Support"
|