Hi, On Wed, Jun 24, 2015 at 8:29 AM, Simon Glass <s...@chromium.org> wrote: > Add a few notes on how to try out the Rockchip support so far. > > Signed-off-by: Simon Glass <s...@chromium.org> > --- > > Changes in v3: > - Update README to mention available drivers > - Add various new patches to get RK3288 booting to a prompt > > Changes in v2: None > > doc/README.rockchip | 246 > ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 246 insertions(+) > create mode 100644 doc/README.rockchip > > diff --git a/doc/README.rockchip b/doc/README.rockchip > new file mode 100644 > index 0000000..a34e198 > --- /dev/null > +++ b/doc/README.rockchip > @@ -0,0 +1,246 @@ > +# > +# Copyright (C) 2015 Google. Inc > +# Written by Simon Glass <s...@chromium.org> > +# > +# SPDX-License-Identifier: GPL-2.0+ > +# > + > +U-Boot on Rockchip > +================== > + > +There are several repositories available with versions of U-Boot that support > +many Rockchip devices [1] [2]. > + > +The current mainline support is experimental only and is not useful for > +anything. It should provide a base on which to build. > + > +So far only support for the RK3288 is provided. > + > + > +Prerequisites > +============= > + > +You will need: > + > + - Firefly RK3288 baord > + - Power connection to 5V using the supplied micro-USB power cable > + - Separate USB serial cable attached to your computer and the Firefly > + (connect to the micro-USB connector below the logo) > + - rkflashtool [3] > + - openssl (sudo apt-get install openssl) > + - Serial UART connection [4] > + - Suitable ARM cross compiler, e.g.: > + sudo apt-get install gcc-4.7-arm-linux-gnueabi > + > + > +Building > +======== > + > +At present three RK3288 boards are supported: > + > + - Firefly RK3288 - use firefly-rk3288 configuration > + - Radxa Rock Pro - also uses firefly-rk3288 configuration > + - Haier Chromebook - use chromebook_jerry configuration > + > +For example: > + > + CROSS_COMPILE=arm-linux-gnueabi- make O=firefly firefly-rk3288_defconfig > all > + > +(or you can use another cross compiler if you prefer) > + > +Note that the Radxa Rock Pro uses the Firefly configuration for now as > +device tree files are not yet available for the Rock Pro. Clearly the two > +have hardware differences, so this approach will break down as more drivers > +are added. > + > + > +Writing to the board with USB > +============================= > + > +For USB to work you must get your board into ROM boot mode, either by erasing > +your MMC or (perhaps) holding the recovery button when you boot the board.
"holding the recovery" method will load & run loader from flash storage (if available). if my memory is correct, SPL cannot be loaded in this case. (rkflashtool l doesn't work) if working (Rockchip's) loader is already loaded, "rkflashtool b 3" might work to enter mask rom mode. https://github.com/linux-rockchip/rkflashtool/commit/f6159af25af766374e1d8a2cb2901d522102b8b8 I'll check it later. > +To erase your MMC, you can boot into Linux and type (as root) > + > + dd if=/dev/zero of=/dev/mmcblk0 bs=1M > + > +Connect your board's OTG port to your computer. > + > +To create a suitable image and write it to the board: > + > + ./firefly-rk3288/tools/mkimage -T rkimage -d > ./firefly-rk3288/spl/u-boot-spl-dtb.bin out > + cat out | openssl rc4 -K 7c4e0304550509072d2c7b38170d1711 | rkflashtool l > + > +If all goes well you should something like: > + > + U-Boot SPL 2015.07-rc1-00383-ge345740-dirty (Jun 03 2015 - 10:06:49) > + Card did not respond to voltage select! > + spl: mmc init failed with error: -17 > + ### ERROR ### Please RESET the board ### > + > +You will need to reset the board before each time you try. Yes, that's all > +it does so far. If support for the Rockchip USB protocol or DFU were added > +in SPL then we could in principle load U-Boot and boot to a prompt from USB > +as several other platforms do. However it does not seem to be possible to > +use the existing boot ROM code from SPL. > + > + > +Booting from an SD card > +======================= > + > +To write an image that boots from an SD card (assumed to be /dev/sdc): > + > + ./firefly-rk3288/tools/mkimage -T rksd -d > firefly-rk3288/spl/u-boot-spl-dtb.bin out > + sudo dd if=out of=/dev/sdc > + sudo dd if=firefly-rk3288/u-boot-dtb.img of=/dev/sdc seek=256 > + > +This puts the Rockchip header and SPL image first and then places the U-Boot > +image at block 256 (i.e. 128KB from the start of the SD card). This > +corresponds with this setting in U-Boot: > + > + #define CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR 256 > + > +Put this SD (or micro-SD) card into your board and reset it. You should see > +something like: > + > + U-Boot SPL 2015.07-rc1-00383-ge345740-dirty (Jun 03 2015 - 11:04:40) > + > + > + U-Boot 2015.07-rc1-00383-ge345740-dirty (Jun 03 2015 - 11:04:40) > + > + DRAM: 2 GiB > + MMC: > + Using default environment > + > + In: serial@ff690000 > + Out: serial@ff690000 > + Err: serial@ff690000 > + => > + > + > +Booting from SPI > +================ > + > +To write an image that boots from SPI flash (e.g. for the Haier Chromebook): > + > + ./chromebook_jerry/tools/mkimage -T rkspi -d > chromebook_jerry/spl/u-boot-spl-dtb.bin out > + dd if=spl.bin of=out.bin bs=128K conv=sync > + cat chromebook_jerry/u-boot-dtb.img out.bin > + dd if=out.bin of=out.bin.pad bs=4M conv=sync > + > +This converts the SPL image to the required SPI format by adding the Rockchip > +header and skipping every 2KB block. Then the U-Boot image is written at > +offset 128KB and the whole image is padded to 4MB which is the SPI flash > size. > +The position of U-Boot is controlled with this setting in U-Boot: > + > + #define CONFIG_SYS_SPI_U_BOOT_OFFS (128 << 10) > + > +If you have a Dediprog em100pro connected then you can write the image with: > + > + sudo em100 -s -c GD25LQ32 -d out.bin.pad -r > + > +When booting you should see something like: > + > + U-Boot SPL 2015.07-rc2-00215-g9a58220-dirty (Jun 23 2015 - 12:11:32) > + > + > + U-Boot 2015.07-rc2-00215-g9a58220-dirty (Jun 23 2015 - 12:11:32 -0600) > + > + Model: Google Jerry > + DRAM: 2 GiB > + MMC: > + Using default environment > + > + In: serial@ff690000 > + Out: serial@ff690000 > + Err: serial@ff690000 > + => > + > + > +Future work > +=========== > + > +Immediate priorities are: > + > +- MMC support (in U-Boot itself) > +- GPIO (driver exists but is lightly tested) > +- I2C (driver exists but is non-functional) > +- USB host > +- USB device > +- PMIC and regulators (only ACT8846 is supported at present) > +- LCD and HDMI > +- Run CPU at full speed > +- Ethernet > +- NAND flash > +- Support for other Rockchip parts > +- Boot U-Boot proper over USB OTG (at present only SPL works) > + > + > +Development Notes > +================= > + > +There are plenty of patches in the links below to help with this work. > + > +[1] https://github.com/rkchrome/uboot.git > +[2] https://github.com/linux-rockchip/u-boot-rockchip.git branch > u-boot-rk3288 > +[3] https://github.com/linux-rockchip/rkflashtool.git > +[4] http://wiki.t-firefly.com/index.php/Firefly-RK3288/Serial_debug/en > + > +rkimage > +------- > + > +rkimage.c produces an SPL image suitable for sending directly to the boot ROM > +over USB OTG. This is a very simple format - just the string RK32 (as 4 > bytes) > +followed by u-boot-spl-dtb.bin. > + > +The boot ROM loads image to 0xff704000 which is in the internal SRAM. The > SRAM > +starts at 0xff700000 and extends to 0xff718000 where we put the stack. > + > +rksd > +---- > + > +rksd.c produces an image consisting of 32KB of empty space, a header and > +u-boot-spl-dtb.bin. The header is defined by 'struct header0_info' although > +most of the fields are unused by U-Boot. We just need to specify the > +signature, a flag and the block offset and size of the SPL image. > + > +The header occupies a single block but we pad it out to 4 blocks. The header > +is encoding using RC4 with the key 7c4e0304550509072d2c7b38170d1711. The SPL > +image can be encoded too but we don't do that. > + > +The maximum size of u-boot-spl-dtb.bin which the boot ROM will read is 32KB, > +or 0x40 blocks. This is a severe and annoying limitation. There may be a way > +around this limitation, since there is plenty of SRAM, but at present the > +board refuses to boot if this limit is exceeded. > + > +The image produced is padded up to a block boundary (512 bytes). It should be > +written to the start of an SD card using dd. > + > +Since this image is set to load U-Boot from the SD card at block offset, > +CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, dd should be used to write > +u-boot-dtb.img to the SD card at that offset. See above for instructions. > + > +rkspi > +----- > + > +rkspi.c produces an image consisting of a header and u-boot-spl-dtb.bin. The > +resulting image is then spread out so that only the first 2KB of each 4KB > +sector is used. The header is the same as with rksd and the maximum size is > +also 32KB (before spreading). The image should be written to the start of > +SPI flash. > + > +See above for instructions on how to write a SPI image. > + > + > +Device tree and driver model > +---------------------------- > + > +Where possible driver model is used to provide a structure to the > +functionality. Device tree is used for configuration. However these have an > +overhead and in SPL with a 32KB size limit some shortcuts have been taken. > +In general all Rockchip drivers should use these features, with SPL-specific > +modifications where required. > + > + > +-- > +Simon Glass <s...@chromium.org> > +24 June 2015 > -- > 2.4.3.573.g4eafbef > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
