mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-14 17:07:38 +00:00
984639039f
The current name is inconsistent with SPL which uses CONFIG_SPL_TEXT_BASE and this makes it imposible to use CONFIG_VAL(). Rename it to resolve this problem. Signed-off-by: Simon Glass <sjg@chromium.org>
697 lines
23 KiB
ReStructuredText
697 lines
23 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0+
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.. Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
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MAIX
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====
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Several of the Sipeed Maix series of boards contain the Kendryte K210 processor,
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a 64-bit RISC-V CPU produced by Canaan Inc. This processor contains several
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peripherals to accelerate neural network processing and other "ai" tasks. This
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includes a "KPU" neural network processor, an audio processor supporting
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beamforming reception, and a digital video port supporting capture and output at
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VGA resolution. Other peripherals include 8M of SRAM (accessible with and
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without caching); remappable pins, including 40 GPIOs; AES, FFT, and SHA256
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accelerators; a DMA controller; and I2C, I2S, and SPI controllers. Maix
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peripherals vary, but include spi flash; on-board usb-serial bridges; ports for
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cameras, displays, and sd cards; and ESP32 chips.
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Currently, only the Sipeed MAIX BiT V2.0 (bitm) and Sipeed MAIXDUINO are
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supported, but the boards are fairly similar.
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Documentation for Maix boards is available from
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`Sipeed's website <http://dl.sipeed.com/MAIX/HDK/>`_.
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Documentation for the Kendryte K210 is available from
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`Kendryte's website <https://kendryte.com/downloads/>`_. However, hardware
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details are rather lacking, so most technical reference has been taken from the
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`standalone sdk <https://github.com/kendryte/kendryte-standalone-sdk>`_.
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Build and boot steps
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--------------------
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To build U-Boot, run
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.. code-block:: none
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make <defconfig>
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make CROSS_COMPILE=<your cross compile prefix>
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To flash U-Boot, run
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.. code-block:: none
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kflash -tp /dev/<your tty here> -B <board_id> u-boot-dtb.bin
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The board provides two serial devices, e.g.
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* /dev/serial/by-id/usb-Kongou_Hikari_Sipeed-Debug_12345678AB-if00-port0
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* /dev/serial/by-id/usb-Kongou_Hikari_Sipeed-Debug_12345678AB-if01-port0
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Which one is used for flashing depends on the board.
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Currently only a small subset of the board features are supported. So we can
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use the same default configuration and device tree. In the long run we may need
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separate settings.
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======================== ========================== ========== ==========
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Board defconfig board_id TTY device
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======================== ========================== ========== ==========
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Sipeed MAIX BiT sipeed_maix_bitm_defconfig bit first
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Sipeed MAIX BiT with Mic sipeed_maix_bitm_defconfig bit_mic first
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Sipeed MAIXDUINO sipeed_maix_bitm_defconfig maixduino first
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Sipeed MAIX GO goE second
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Sipeed MAIX ONE DOCK dan first
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======================== ========================== ========== ==========
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Flashing causes a reboot of the device. Parameter -t specifies that the serial
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console shall be opened immediately. Boot output should look like the following:
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.. code-block:: none
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U-Boot 2020.04-rc2-00087-g2221cc09c1-dirty (Feb 28 2020 - 13:53:09 -0500)
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DRAM: 8 MiB
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MMC: spi@53000000:slot@0: 0
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In: serial@38000000
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Out: serial@38000000
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Err: serial@38000000
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=>
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OpenSBI
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^^^^^^^
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OpenSBI is an open source supervisor execution environment implementing the
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RISC-V Supervisor Binary Interface Specification [1]. One of its features is
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to intercept run-time exceptions, e.g. for unaligned access or illegal
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instructions, and to emulate the failing instructions.
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The OpenSBI source can be downloaded via:
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.. code-block:: bash
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git clone https://github.com/riscv/opensbi
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As OpenSBI will be loaded at 0x80000000 we have to adjust the U-Boot text base.
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Furthermore we have to enable building U-Boot for S-mode::
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CONFIG_TEXT_BASE=0x80020000
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CONFIG_RISCV_SMODE=y
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Both settings are contained in sipeed_maix_smode_defconfig so we can build
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U-Boot with:
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.. code-block:: bash
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make sipeed_maix_smode_defconfig
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make
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To build OpenSBI with U-Boot as a payload:
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.. code-block:: bash
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cd opensbi
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make \
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PLATFORM=kendryte/k210 \
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FW_PAYLOAD=y \
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FW_PAYLOAD_OFFSET=0x20000 \
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FW_PAYLOAD_PATH=<path to U-Boot>/u-boot-dtb.bin
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The value of FW_PAYLOAD_OFFSET must match CONFIG_TEXT_BASE - 0x80000000.
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The file to flash is build/platform/kendryte/k210/firmware/fw_payload.bin.
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Booting
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^^^^^^^
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The default boot process is to load and boot the files ``/uImage`` and
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``/k210.dtb`` off of the first partition of the MMC. For Linux, this will result
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in an output like
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.. code-block:: none
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U-Boot 2020.10-00691-gd1d651d988-dirty (Oct 16 2020 - 17:05:24 -0400)
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DRAM: 8 MiB
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MMC: spi@53000000:slot@0: 0
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Loading Environment from SPIFlash... SF: Detected w25q128fw with page size 256 Bytes, erase size 4 KiB, total 16 MiB
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OK
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In: serial@38000000
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Out: serial@38000000
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Err: serial@38000000
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Hit any key to stop autoboot: 0
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1827380 bytes read in 1044 ms (1.7 MiB/s)
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13428 bytes read in 10 ms (1.3 MiB/s)
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## Booting kernel from Legacy Image at 80060000 ...
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Image Name: linux
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Image Type: RISC-V Linux Kernel Image (uncompressed)
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Data Size: 1827316 Bytes = 1.7 MiB
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Load Address: 80000000
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Entry Point: 80000000
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Verifying Checksum ... OK
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## Flattened Device Tree blob at 80400000
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Booting using the fdt blob at 0x80400000
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Loading Kernel Image
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Loading Device Tree to 00000000803f9000, end 00000000803ff473 ... OK
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Starting kernel ...
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[ 0.000000] Linux version 5.9.0-00021-g6dcc2f0814c6-dirty (sean@godwin) (riscv64-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.35) #34 SMP Fri Oct 16 14:40:57 EDT 2020
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[ 0.000000] earlycon: sifive0 at MMIO 0x0000000038000000 (options '115200n8')
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[ 0.000000] printk: bootconsole [sifive0] enabled
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[ 0.000000] Zone ranges:
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[ 0.000000] DMA32 [mem 0x0000000080000000-0x00000000807fffff]
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[ 0.000000] Normal empty
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[ 0.000000] Movable zone start for each node
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[ 0.000000] Early memory node ranges
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[ 0.000000] node 0: [mem 0x0000000080000000-0x00000000807fffff]
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[ 0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x00000000807fffff]
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[ 0.000000] riscv: ISA extensions acdfgim
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[ 0.000000] riscv: ELF capabilities acdfim
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[ 0.000000] percpu: max_distance=0x18000 too large for vmalloc space 0x0
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[ 0.000000] percpu: Embedded 12 pages/cpu s18848 r0 d30304 u49152
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[ 0.000000] Built 1 zonelists, mobility grouping off. Total pages: 2020
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[ 0.000000] Kernel command line: earlycon console=ttySIF0
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[ 0.000000] Dentry cache hash table entries: 1024 (order: 1, 8192 bytes, linear)
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[ 0.000000] Inode-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
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[ 0.000000] Sorting __ex_table...
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[ 0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
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[ 0.000000] Memory: 6004K/8192K available (1139K kernel code, 126K rwdata, 198K rodata, 90K init, 81K bss, 2188K reserved, 0K cma-reserved)
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[ 0.000000] rcu: Hierarchical RCU implementation.
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[ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
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[ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
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[ 0.000000] riscv-intc: 64 local interrupts mapped
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[ 0.000000] plic: interrupt-controller@C000000: mapped 65 interrupts with 2 handlers for 2 contexts.
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[ 0.000000] random: get_random_bytes called from 0x00000000800019a8 with crng_init=0
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[ 0.000000] k210-clk: clock-controller
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[ 0.000000] k210-clk: clock-controller: fixed-rate 26 MHz osc base clock
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[ 0.000000] clint: clint@2000000: timer running at 7800000 Hz
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[ 0.000000] clocksource: clint_clocksource: mask: 0xffffffffffffffff max_cycles: 0x3990be68b, max_idle_ns: 881590404272 ns
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[ 0.000014] sched_clock: 64 bits at 7MHz, resolution 128ns, wraps every 4398046511054ns
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[ 0.008450] Console: colour dummy device 80x25
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[ 0.012494] Calibrating delay loop (skipped), value calculated using timer frequency.. 15.60 BogoMIPS (lpj=31200)
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[ 0.022693] pid_max: default: 4096 minimum: 301
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[ 0.027352] Mount-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
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[ 0.034428] Mountpoint-cache hash table entries: 512 (order: 0, 4096 bytes, linear)
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[ 0.045099] rcu: Hierarchical SRCU implementation.
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[ 0.050048] smp: Bringing up secondary CPUs ...
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[ 0.055417] smp: Brought up 1 node, 2 CPUs
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[ 0.059602] devtmpfs: initialized
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[ 0.082796] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns
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[ 0.091820] futex hash table entries: 16 (order: -2, 1024 bytes, linear)
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[ 0.098507] pinctrl core: initialized pinctrl subsystem
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[ 0.140938] clocksource: Switched to clocksource clint_clocksource
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[ 0.247216] workingset: timestamp_bits=62 max_order=11 bucket_order=0
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[ 0.277392] k210-fpioa 502b0000.pinmux: K210 FPIOA pin controller
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[ 0.291724] k210-sysctl 50440000.syscon: K210 system controller
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[ 0.305317] k210-rst 50440000.syscon:reset-controller: K210 reset controller
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[ 0.313808] 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 115200) is a SiFive UART v0
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[ 0.322712] printk: console [ttySIF0] enabled
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[ 0.322712] printk: console [ttySIF0] enabled
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[ 0.331328] printk: bootconsole [sifive0] disabled
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[ 0.331328] printk: bootconsole [sifive0] disabled
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[ 0.353347] Freeing unused kernel memory: 88K
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[ 0.357004] This architecture does not have kernel memory protection.
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[ 0.363397] Run /init as init process
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Loading, Booting, and Storing Images
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------------------------------------
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.. _loading:
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Loading Images
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^^^^^^^^^^^^^^
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Serial
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""""""
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Use the ``loady`` command to load images over serial.
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.. code-block:: none
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=> loady $loadaddr 1500000
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## Switch baudrate to 1500000 bps and press ENTER ...
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*** baud: 1500000
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*** baud: 1500000 ***
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## Ready for binary (ymodem) download to 0x80000000 at 1500000 bps...
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C
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*** file: loader.bin
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$ sz -vv loader.bin
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Sending: loader.bin
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Bytes Sent:2478208 BPS:72937
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Sending:
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Ymodem sectors/kbytes sent: 0/ 0k
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Transfer complete
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*** exit status: 0 ***
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## Total Size = 0x0025d052 = 2478162 Bytes
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## Switch baudrate to 115200 bps and press ESC ...
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*** baud: 115200
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*** baud: 115200 ***
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=>
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This command does not set ``$filesize``, so it may need to be set manually.
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SPI Flash
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"""""""""
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To load an image off of SPI flash, first set up a partition as described in
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:ref:`k210_partitions`. Then, use ``mtd`` to load that partition
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.. code-block:: none
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=> sf probe
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SF: Detected w25q128fw with page size 256 Bytes, erase size 4 KiB, total 16 MiB
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=> mtd read linux $loadaddr
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Reading 2097152 byte(s) at offset 0x00000000
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This command does not set ``$filesize``, so it may need to be set manually.
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MMC
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"""
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The MMC device number is 0. To list partitions on the device, use ``part``:
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.. code-block:: none
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=> part list mmc 0
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Partition Map for MMC device 0 -- Partition Type: EFI
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Part Start LBA End LBA Name
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Attributes
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Type GUID
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Partition GUID
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1 0x00000800 0x039effde "boot"
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attrs: 0x0000000000000000
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type: c12a7328-f81f-11d2-ba4b-00a0c93ec93b
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guid: 96161f7d-7113-4cc7-9a24-08ab7fc5cb72
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To list files, use ``ls``:
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.. code-block:: none
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=> ls mmc 0:1
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<DIR> 4096 .
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<DIR> 4096 ..
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<DIR> 16384 lost+found
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13428 k210.dtb
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1827380 uImage
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To load a file, use ``load``:
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.. code-block:: none
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=> load mmc 0:1 $loadaddr uImage
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1827380 bytes read in 1049 ms (1.7 MiB/s)
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Running Programs
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^^^^^^^^^^^^^^^^
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Binaries
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""""""""
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To run a bare binary, use the ``go`` command:
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.. code-block:: none
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=> go 80000000
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## Starting application at 0x80000000 ...
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Example expects ABI version 9
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Actual U-Boot ABI version 9
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Hello World
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argc = 1
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argv[0] = "80000000"
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argv[1] = "<NULL>"
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Hit any key to exit ...
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Note that this will only start a program on one hart. As-of this writing it is
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only possible to start a program on multiple harts using the ``bootm`` command.
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Legacy Images
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"""""""""""""
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To create a legacy image, use ``tools/mkimage``:
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.. code-block:: none
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$ tools/mkimage -A riscv -O linux -T kernel -C none -a 0x80000000 -e 0x80000000 -n linux -d ../linux-git/arch/riscv/boot/Image uImage
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Image Name: linux
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Created: Fri Oct 16 17:36:32 2020
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Image Type: RISC-V Linux Kernel Image (uncompressed)
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Data Size: 1827316 Bytes = 1784.49 KiB = 1.74 MiB
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Load Address: 80000000
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Entry Point: 80000000
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The ``bootm`` command also requires an FDT, even if the image doesn't require
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one. After loading the image to ``$loadaddr`` and the FDT to ``$fdt_addr_r``,
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boot with:
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.. code-block:: none
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=> bootm $loadaddr - $fdt_addr_r
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## Booting kernel from Legacy Image at 80060000 ...
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Image Name: linux
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Image Type: RISC-V Linux Kernel Image (uncompressed)
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Data Size: 1827316 Bytes = 1.7 MiB
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Load Address: 80000000
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Entry Point: 80000000
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Verifying Checksum ... OK
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## Flattened Device Tree blob at 80400000
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Booting using the fdt blob at 0x80400000
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Loading Kernel Image
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Loading Device Tree to 00000000803f9000, end 00000000803ff473 ... OK
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Starting kernel ...
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The FDT is verified after the kernel is relocated, so it must be loaded high
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enough so that it won't be overwritten. The default values for ``$loadaddr``
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and ``$fdt_addr_r`` should provide ample headroom for most use-cases.
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Flashing Images
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^^^^^^^^^^^^^^^
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SPI Flash
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"""""""""
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To flash data to SPI flash, first load it using one of the methods in
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:ref:`loading`. Addiotionally, create some partitions as described in
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:ref:`partitions`. Then use the ``mtd`` command:
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.. code-block:: none
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=> sf probe
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SF: Detected w25q128fw with page size 256 Bytes, erase size 4 KiB, total 16 MiB
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=> mtd write linux $loadaddr 0 $filesize
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Writing 2478162 byte(s) at offset 0x00000000
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Note that in order to write a bootable image, a header and tailer must be added.
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MMC
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"""
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MMC writes are unsupported for now.
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SPI Flash
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^^^^^^^^^
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Sipeed MAIX boards typically provide around 16 MiB of SPI NOR flash. U-Boot is
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stored in the first 1 MiB or so of this flash. U-Boot's environment is stored at
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the end of flash.
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.. _k210_partitions:
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Partitions
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""""""""""
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There is no set data layout. The default partition layout only allocates
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partitions for U-Boot and its default environment
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.. code-block:: none
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=> mtd list
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List of MTD devices:
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* nor0
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- type: NOR flash
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- block size: 0x1000 bytes
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- min I/O: 0x1 bytes
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- 0x000000000000-0x000001000000 : "nor0"
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- 0x000000000000-0x000000100000 : "u-boot"
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- 0x000000fff000-0x000001000000 : "env"
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As an example, to allocate 2MiB for Linux and (almost) 13 MiB for other data,
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set the ``mtdparts`` like:
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.. code-block:: none
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=> env set mtdparts nor0:1M(u-boot),2M(linux),0xcff000(data),0x1000@0xfff000(env)
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=> mtd list
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List of MTD devices:
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* nor0
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- type: NOR flash
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- block size: 0x1000 bytes
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- min I/O: 0x1 bytes
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- 0x000000000000-0x000001000000 : "nor0"
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- 0x000000000000-0x000000100000 : "u-boot"
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- 0x000000100000-0x000000300000 : "linux"
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- 0x000000300000-0x000000fff000 : "data"
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- 0x000000fff000-0x000001000000 : "env"
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To make these changes permanent, save the environment:
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.. code-block:: none
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=> env save
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Saving Environment to SPIFlash... Erasing SPI flash...Writing to SPI flash...done
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OK
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U-Boot will always load the environment from the last 4 KiB of flash.
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Pin Assignment
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--------------
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The K210 contains a Fully Programmable I/O Array (FPIOA), which can remap any of
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its 256 input functions to any any of 48 output pins. The following table has
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the default pin assignments for the BitM.
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===== ========== =======
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Pin Function Comment
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===== ========== =======
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IO_0 JTAG_TCLK
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IO_1 JTAG_TDI
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IO_2 JTAG_TMS
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IO_3 JTAG_TDO
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IO_4 UARTHS_RX
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IO_5 UARTHS_TX
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IO_6 Not set
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IO_7 Not set
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IO_8 GPIO_0
|
|
IO_9 GPIO_1
|
|
IO_10 GPIO_2
|
|
IO_11 GPIO_3
|
|
IO_12 GPIO_4 Green LED
|
|
IO_13 GPIO_5 Red LED
|
|
IO_14 GPIO_6 Blue LED
|
|
IO_15 GPIO_7
|
|
IO_16 GPIOHS_0 ISP
|
|
IO_17 GPIOHS_1
|
|
IO_18 I2S0_SCLK MIC CLK
|
|
IO_19 I2S0_WS MIC WS
|
|
IO_20 I2S0_IN_D0 MIC SD
|
|
IO_21 GPIOHS_5
|
|
IO_22 GPIOHS_6
|
|
IO_23 GPIOHS_7
|
|
IO_24 GPIOHS_8
|
|
IO_25 GPIOHS_9
|
|
IO_26 SPI1_D1 MMC MISO
|
|
IO_27 SPI1_SCLK MMC CLK
|
|
IO_28 SPI1_D0 MMC MOSI
|
|
IO_29 GPIOHS_13 MMC CS
|
|
IO_30 GPIOHS_14
|
|
IO_31 GPIOHS_15
|
|
IO_32 GPIOHS_16
|
|
IO_33 GPIOHS_17
|
|
IO_34 GPIOHS_18
|
|
IO_35 GPIOHS_19
|
|
IO_36 GPIOHS_20 Panel CS
|
|
IO_37 GPIOHS_21 Panel RST
|
|
IO_38 GPIOHS_22 Panel DC
|
|
IO_39 SPI0_SCK Panel WR
|
|
IO_40 SCCP_SDA
|
|
IO_41 SCCP_SCLK
|
|
IO_42 DVP_RST
|
|
IO_43 DVP_VSYNC
|
|
IO_44 DVP_PWDN
|
|
IO_45 DVP_HSYNC
|
|
IO_46 DVP_XCLK
|
|
IO_47 DVP_PCLK
|
|
===== ========== =======
|
|
|
|
Over- and Under-clocking
|
|
------------------------
|
|
|
|
To change the clock speed of the K210, you will need to enable
|
|
``CONFIG_CLK_K210_SET_RATE`` and edit the board's device tree. To do this, add a
|
|
section to ``arch/riscv/arch/riscv/dts/k210-maix-bit.dts`` like the following:
|
|
|
|
.. code-block:: none
|
|
|
|
&sysclk {
|
|
assigned-clocks = <&sysclk K210_CLK_PLL0>;
|
|
assigned-clock-rates = <800000000>;
|
|
};
|
|
|
|
There are three PLLs on the K210: PLL0 is the parent of most of the components,
|
|
including the CPU and RAM. PLL1 is the parent of the neural network coprocessor.
|
|
PLL2 is the parent of the sound processing devices. Note that child clocks of
|
|
PLL0 and PLL2 run at *half* the speed of the PLLs. For example, if PLL0 is
|
|
running at 800 MHz, then the CPU will run at 400 MHz. This is the example given
|
|
above. The CPU can be overclocked to around 600 MHz, and underclocked to 26 MHz.
|
|
|
|
It is possible to set PLL2's parent to PLL0. The plls are more accurate when
|
|
converting between similar frequencies. This makes it easier to get an accurate
|
|
frequency for I2S. As an example, consider sampling an I2S device at 44.1 kHz.
|
|
On this device, the I2S serial clock runs at 64 times the sample rate.
|
|
Therefore, we would like to run PLL2 at an even multiple of 2.8224 MHz. If
|
|
PLL2's parent is IN0, we could use a frequency of 390 MHz (the same as the CPU's
|
|
default speed). Dividing by 138 yields a serial clock of about 2.8261 MHz. This
|
|
results in a sample rate of 44.158 kHz---around 50 Hz or .1% too fast. If,
|
|
instead, we set PLL2's parent to PLL1 running at 390 MHz, and request a rate of
|
|
2.8224 * 136 = 383.8464 MHz, the achieved rate is 383.90625 MHz. Dividing by 136
|
|
yields a serial clock of about 2.8228 MHz. This results in a sample rate of
|
|
44.107 kHz---just 7 Hz or .02% too fast. This configuration is shown in the
|
|
following example:
|
|
|
|
.. code-block:: none
|
|
|
|
&sysclk {
|
|
assigned-clocks = <&sysclk K210_CLK_PLL1>, <&sysclk K210_CLK_PLL2>;
|
|
assigned-clock-parents = <0>, <&sysclk K210_CLK_PLL1>;
|
|
assigned-clock-rates = <390000000>, <383846400>;
|
|
};
|
|
|
|
There are a couple of quirks to the PLLs. First, there are more frequency ratios
|
|
just above and below 1.0, but there is a small gap around 1.0. To be explicit,
|
|
if the input frequency is 100 MHz, it would be impossible to have an output of
|
|
99 or 101 MHz. In addition, there is a maximum frequency for the internal VCO,
|
|
so higher input/output frequencies will be less accurate than lower ones.
|
|
|
|
Technical Details
|
|
-----------------
|
|
|
|
Boot Sequence
|
|
^^^^^^^^^^^^^
|
|
|
|
1. ``RESET`` pin is deasserted. The pin is connected to the ``RESET`` button. It
|
|
can also be set to low via either the ``DTR`` or the ``RTS`` line of the
|
|
serial interface (depending on the board).
|
|
2. Both harts begin executing at ``0x00001000``.
|
|
3. Both harts jump to firmware at ``0x88000000``.
|
|
4. One hart is chosen as a boot hart.
|
|
5. Firmware reads the value of pin ``IO_16`` (ISP). This pin is connected to the
|
|
``BOOT`` button. The pin can equally be set to low via either the ``DTR`` or
|
|
``RTS`` line of the serial interface (depending on the board).
|
|
|
|
* If the pin is low, enter ISP mode. This mode allows loading data to ram,
|
|
writing it to flash, and booting from specific addresses.
|
|
* If the pin is high, continue boot.
|
|
6. Firmware reads the next stage from flash (SPI3) to address ``0x80000000``.
|
|
|
|
* If byte 0 is 1, the next stage is decrypted using the built-in AES
|
|
accelerator and the one-time programmable, 128-bit AES key.
|
|
* Bytes 1 to 4 hold the length of the next stage.
|
|
* The SHA-256 sum of the next stage is automatically calculated, and verified
|
|
against the 32 bytes following the next stage.
|
|
7. The boot hart sends an IPI to the other hart telling it to jump to the next
|
|
stage.
|
|
8. The boot hart jumps to ``0x80000000``.
|
|
|
|
Debug UART
|
|
^^^^^^^^^^
|
|
|
|
The Debug UART is provided with the following settings::
|
|
|
|
CONFIG_DEBUG_UART=y
|
|
CONFIG_DEBUG_UART_SIFIVE=y
|
|
CONFIG_DEBUG_UART_BASE=0x38000000
|
|
CONFIG_DEBUG_UART_CLOCK=390000000
|
|
|
|
Resetting the board
|
|
^^^^^^^^^^^^^^^^^^^
|
|
|
|
The MAIX boards can be reset using the DTR and RTS lines of the serial console.
|
|
How the lines are used depends on the specific board. See the code of kflash.py
|
|
for details.
|
|
|
|
This is the reset sequence for the MAXDUINO and MAIX BiT with Mic:
|
|
|
|
.. code-block:: python
|
|
|
|
def reset(self):
|
|
self.device.setDTR(False)
|
|
self.device.setRTS(False)
|
|
time.sleep(0.1)
|
|
self.device.setDTR(True)
|
|
time.sleep(0.1)
|
|
self.device.setDTR(False)
|
|
time.sleep(0.1)
|
|
|
|
and this for the MAIX Bit:
|
|
|
|
.. code-block:: python
|
|
|
|
def reset(self):
|
|
self.device.setDTR(False)
|
|
self.device.setRTS(False)
|
|
time.sleep(0.1)
|
|
self.device.setRTS(True)
|
|
time.sleep(0.1)
|
|
self.device.setRTS(False)
|
|
time.sleep(0.1)
|
|
|
|
Memory Map
|
|
^^^^^^^^^^
|
|
|
|
========== ========= ===========
|
|
Address Size Description
|
|
========== ========= ===========
|
|
0x00000000 0x1000 debug
|
|
0x00001000 0x1000 rom
|
|
0x02000000 0xC000 clint
|
|
0x0C000000 0x4000000 plic
|
|
0x38000000 0x1000 uarths
|
|
0x38001000 0x1000 gpiohs
|
|
0x40000000 0x400000 sram0 (non-cached)
|
|
0x40400000 0x200000 sram1 (non-cached)
|
|
0x40600000 0x200000 airam (non-cached)
|
|
0x40800000 0xC00000 kpu
|
|
0x42000000 0x400000 fft
|
|
0x50000000 0x1000 dmac
|
|
0x50200000 0x200000 apb0
|
|
0x50200000 0x80 gpio
|
|
0x50210000 0x100 uart0
|
|
0x50220000 0x100 uart1
|
|
0x50230000 0x100 uart2
|
|
0x50240000 0x100 spi slave
|
|
0x50250000 0x200 i2s0
|
|
0x50250200 0x200 apu
|
|
0x50260000 0x200 i2s1
|
|
0x50270000 0x200 i2s2
|
|
0x50280000 0x100 i2c0
|
|
0x50290000 0x100 i2c1
|
|
0x502A0000 0x100 i2c2
|
|
0x502B0000 0x100 fpioa
|
|
0x502C0000 0x100 sha256
|
|
0x502D0000 0x100 timer0
|
|
0x502E0000 0x100 timer1
|
|
0x502F0000 0x100 timer2
|
|
0x50400000 0x200000 apb1
|
|
0x50400000 0x100 wdt0
|
|
0x50410000 0x100 wdt1
|
|
0x50420000 0x100 otp control
|
|
0x50430000 0x100 dvp
|
|
0x50440000 0x100 sysctl
|
|
0x50450000 0x100 aes
|
|
0x50460000 0x100 rtc
|
|
0x52000000 0x4000000 apb2
|
|
0x52000000 0x100 spi0
|
|
0x53000000 0x100 spi1
|
|
0x54000000 0x200 spi3
|
|
0x80000000 0x400000 sram0 (cached)
|
|
0x80400000 0x200000 sram1 (cached)
|
|
0x80600000 0x200000 airam (cached)
|
|
0x88000000 0x20000 otp
|
|
0x88000000 0xC200 firmware
|
|
0x8801C000 0x1000 riscv priv spec 1.9 config
|
|
0x8801D000 0x2000 flattened device tree (contains only addresses and
|
|
interrupts)
|
|
0x8801F000 0x1000 credits
|
|
========== ========= ===========
|
|
|
|
Links
|
|
-----
|
|
|
|
[1] https://github.com/riscv/riscv-sbi-doc
|
|
RISC-V Supervisor Binary Interface Specification
|