linux XIP 启动时间问题

sz su

Other Parts Discussed in Thread: OMAP-L138

我们这边是OMAP-138的板子，有一块nor flash，想要加快linux启动时间

测试使用了XIP 的启动方式，但是启动时间并没有加快，和传统的拷贝、解压内核所需要的时间比较，并没有快，总体上时间差不多

据网上很多资料的介绍，XIP 启动方式由于省略了uimage 的拷贝和解压，启动速度理论上是会加快的

请问这里为什么，还是我们这边那里设置不正确吗？

CE4 = 0x01000001
Finished LCD Init!!!!!!!!!!!!!!!!!!!!!!!
SF: Detected MX25L12805D with page size 256, total 16777216 bytes
Hit any key to stop autoboot: 0
## Booting kernel from Legacy Image at 60000000 ...
   Image Name:   XIP Image
   Image Type:   ARM Linux Kernel Image (uncompressed)
   Data Size:    7306976 Bytes = 7 MB
   Load Address: 60000000
   Entry Point: 60000040
   Verifying Checksum ... OK
   XIP Kernel Image ... OK
OK

Starting kernel ...

    0.000000] Linux version 2.6.33-rc4-D8135_2.0.1.4 (root@eastcom) (gcc version 4.3.3 (Sourcery G++ Lite 2009q1-203) ) #514 PREEMPT Thu May 4 10:19:33 CST 2017
[    0.000000] CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00053177
[    0.000000] CPU: VIVT data cache, VIVT instruction cache
[    0.000000] Machine: DaVinci DA850/OMAP-L138/AM18xx EVM
[    0.000000] Ignoring unrecognised tag 0x54410009
[    0.000000] Memory policy: ECC disabled, Data cache writeback
[    0.000000] DaVinci da850/omap-l138/am18xx variant 0x1
[    0.000000] init_pll0_iomap ok
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 23876
[    0.000000] Kernel command line: mem=94M console=ttyS0,115200n8 init=/init
[    0.000000] PID hash table entries: 512 (order: -1, 2048 bytes)
[    0.000000] Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
[    0.000000] Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
[    0.000000] Memory: 94MB = 94MB total
[    0.000000] Memory: 94548KB available (2700K code, 733K data, 12K init, 0K highmem)
[    0.000000] Hierarchical RCU implementation.
[    0.000000] NR_IRQS:245
[    0.000000] davinci_clock_tick_rate: 24000000
[    0.000000] Calibrating delay loop... 98.09 BogoMIPS (lpj=245248)
[    0.085000] Mount-cache hash table entries: 512
[    0.100000] CPU: Testing write buffer coherency: ok
[    0.205000] regulator: core version 0.5
[    0.225000] NET: Registered protocol family 16
[    1.075000] bio: create slab <bio-0> at 0
[    1.375000] regulator: VDCDC1: 3200 <--> 3300 mV at 3300 mV
[    1.400000] regulator: VDCDC2: 1750 <--> 3300 mV at 3300 mV
[    1.420000] regulator: VDCDC3: 950 <--> 1375 mV at 1200 mV
[    1.445000] regulator: LDO1: 1800 mV
[    1.465000] regulator: LDO2: 1150 <--> 1300 mV at 1200 mV
[    1.570000] i2c-gpio i2c-gpio.1: using pins 20 (SDA) and 21 (SCL)
[    1.685000] Switching to clocksource timer0_1
[    1.875000] musb_hdrc: version 6.0, cppi4.1-dma, peripheral, debug=0
[    1.910000] Waiting for USB PHY clock good...
[    1.925000] musb_hdrc: USB Peripheral mode controller at fee00000 using DMA, IRQ 58
[    1.950000] NET: Registered protocol family 2
[    1.960000] IP route cache hash table entries: 1024 (order: 0, 4096 bytes)
[    1.975000] TCP established hash table entries: 4096 (order: 3, 32768 bytes)
[    1.975000] TCP bind hash table entries: 4096 (order: 2, 16384 bytes)
[    1.975000] TCP: Hash tables configured (established 4096 bind 4096)
[    1.975000] TCP reno registered
[    1.975000] UDP hash table entries: 256 (order: 0, 4096 bytes)
[    1.980000] UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
[    1.990000] NET: Registered protocol family 1
[    5.240000] msgmni has been set to 184
[    5.620000] io scheduler noop registered
[    5.620000] io scheduler deadline registered
[    5.625000] io scheduler cfq registered (default)
[    5.635000] da8xx_lcdc da8xx_lcdc.0: GLCD: Found sitronix_st7735s panel
[    5.670000] lcd fresh start address:0xc5161000
[    5.760000] Serial: 8250/16550 driver, 3 ports, IRQ sharing disabled
[    5.870000] serial8250.0: ttyS0 at MMIO 0x1c42000 (irq = 25) is a 16550A
[    6.155000] console [ttyS0] enabled

8 年多前