linux tinydrm vs fbtft 性能对比测试

news/2024/7/7 0:33:28/文章来源:https://www.cnblogs.com/hfwz/p/18280744

linux tinydrm vs fbtft 性能对比测试

本文将通过若干组对照试验，然后根据实验得出的数据，计算在使用fbdev的情况下，tinydrm相较于fbtft的提升幅度。

免责声明：本人时间、精力有限，实验中的测试数据量较小，所以不建议将本文中的数据用于比较严谨的场景。

测试环境


开发板	树莓派1代B型号 Raspberrypi Model B
CPU	BCM2835 armv6l ARM1176@1GHz 已超频，详细参数见下方config.txt
屏幕	128x160 st7735r 4-wire spi@12MHz

cpuinfo

Architecture:           armv6lByte Order:           Little Endian
CPU(s):                 1On-line CPU(s) list:  0
Vendor ID:              ARMModel name:           ARM1176Model:              7Thread(s) per core: 1Core(s) per socket: 1Socket(s):          1Stepping:           r0p7CPU(s) scaling MHz: 70%CPU max MHz:        1000.0000CPU min MHz:        700.0000BogoMIPS:           697.95Flags:              half thumb fastmult vfp edsp java tls

测试用例

Linux Framebuffer Benchmark : https://github.com/caramelli/fbmark

编译选项： -g -O2

fb_rectangle
fb_sierpinski

工具链信息

❯ /opt/cross-pi-gcc/bin/arm-linux-gnueabihf-gcc -v
Using built-in specs.
COLLECT_GCC=/opt/cross-pi-gcc/bin/arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/opt/cross-pi-gcc/libexec/gcc/arm-linux-gnueabihf/12.2.0/lto-wrapper
Target: arm-linux-gnueabihf
Configured with: ../gcc-12.2.0/configure --prefix=/opt/cross-pi-gcc --target=arm-linux-gnueabihf --enable-languages=c,c++,fortran --with-arch=armv6 --with-fpu=vfp --with-float=hard --disable-multilib --includedir=/usr/arm-linux-gnueabihf/include
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 12.2.0 (GCC)

自建工具链方法参考：https://solarianprogrammer.com/2018/05/06/building-gcc-cross-compiler-raspberry-pi/ （此文中的编译选项不针对于树莓派1b。我修改了一些编译选项以及其他参数，方才可以使用，目前正在整理中，尚未发布。）

一般情况下，您不需要自建交叉编译工具链，使用apt或buildroot提供的工具链进行编译即可。

config.txt

# Please note that this is only a sample, we recommend you to change it to fit
# your needs.
# You should override this file using BR2_PACKAGE_RPI_FIRMWARE_CONFIG_FILE.
# See http://buildroot.org/manual.html#rootfs-custom
# and http://elinux.org/RPiconfig for a description of config.txt syntaxstart_file=start.elf
fixup_file=fixup.datkernel=zImage# To use an external initramfs file
#initramfs rootfs.cpio.gz# Disable overscan assuming the display supports displaying the full resolution
# If the text shown on the screen disappears off the edge, comment this out
disable_overscan=1# How much memory in MB to assign to the GPU on Pi models having
# 256, 512 or 1024 MB total memory
gpu_mem_256=100
gpu_mem_512=100
gpu_mem_1024=100enable_uart=1
dtoverlay=i2c1-overlay
arm_freq=1000
core_freq=500
sdram_freq=600
over_voltage=6

成绩对比

开启fbcon cursor_blink

echo 1 > /sys/class/graphics/fbcon/cursor_blink

	fbtft	tinydrm	提升幅度	单位
Rectangle 32x40	8.55	17.54	51.26%	MPixels/second
Sierpinski 1024	529.41	1138.67	53.51%	Frames/second
Sierpinski 2048	295.23	605.58	51.25%	Frames/second
Sierpinski 4096	156.19	314.06	50.27%	Frames/second
Sierpinski 8192	80.00	160.37	50.12%	Frames/second
Sierpinski 16384	42.86	80.83	46.98%	Frames/second
Sierpinski 32768	23.81	41.01	41.95%	Frames/second
Sierpinski 65536	14.28	20.76	31.21%	Frames/second
Sierpinski 131072	9.53	10.42	8.54%	Frames/second
Sierpinski 262144	5.30	5.30	0.00%	Frames/second

结论：在多个测试项目中，tinydrm 对比 fbtft 具有100%的性能提升。

在后面的测试项目中，随着计算复杂度的提升，tinydrm的领先幅度大幅下降，推测瓶颈可能来到cpu这边，暂未进行验证，需要更多数据支持该推测。

关闭fbcon cursor_blink

echo 0 > /sys/class/graphics/fbcon/cursor_blink

	fbtft	tinydrm	单位
Rectangle 32x40	9.04	17.61	MPixels/second
Sierpinski 1024	586.80	1142.07	Frames/second
Sierpinski 2048	314.59	608.69	Frames/second
Sierpinski 4096	165.51	314.93	Frames/second
Sierpinski 8192	82.88	160.95	Frames/second
Sierpinski 16384	43.46	81.07	Frames/second
Sierpinski 32768	27.63	41.17	Frames/second
Sierpinski 65536	17.76	20.84	Frames/second
Sierpinski 131072	9.23	10.46	Frames/second
Sierpinski 262144	5.31	5.31	Frames/second