前段时间ST推出了Value Line的STM32F750和H750两个系列，看了一下选型表，F750有LQFP144封装，正好适合我的STM32 linux板子。

! w4 n, p1 ^3 S0 S; ]% o2 o- P6 s% C
于是，双十一买了几片。同时，我对我的linux板做了小幅改版：将SPI Flash容量扩大到32MB并连接到F750的QSPI
BANK1，添加了CAN收发器和接口，增加了两个I2C外设（温湿度传感器和气压传感器）。板子做回来后先焊了一片，调试过程还算比较顺利，现在u-boot和Linux都工作起来了，下面是系统启动log，F750速度还是相当快的（427.62
BogoMIPS，F429跑Linux只有35.84
3 y, C1 W" L. Z: Z& N; [" ?BogoMIPS），QSPI的加载速度也很给力。下一步我准备多测试几种STM32外设的Linux
driver，emcraft现在的SDK比两三年前多了不少外设驱动，可以都试试看。
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6 J% o: t' o9 D- N5 x




U-Boot 2010.03 (Nov 26 2018 - 21:30:21)
6 q# H9 T, w1 Z5 U& W6 f5 ?
# a- n- g4 n8 a; w3 YCPU  : STM32F7 (Cortex-M7)
  I  j5 _  Y5 R4 J' C; [Freqs: SYSCLK=216MHz,HCLK=216MHz,PCLK1=54MHz,PCLK2=108MHz
DRAM:  64 MB
In:    serial
) A3 ]) Z2 {( V2 ~. mOut:   serial
Err:   serial
QSPI:  32 MB mapped at 0x90000000
Net:   miiphy_register done.
) i6 R! q& I6 Z0 Feth hw init done.
  |- p0 v; H9 i* s" eSTM32_MAC
6 p+ h6 V1 |2 _* m, b8 F# G% x) `Hit any key to stop autoboot:  0
Booting from QSPI
/ A( O- c; e8 }+ N. I! h## Booting kernel from Legacy Image at c0007fc0 ...
   Image Name:   Linux-4.2.0
   Image Type:   ARM Linux Multi-File Image (uncompressed)
" e) t0 p1 h$ r- E+ [   Data Size:    7496295 Bytes =  7.1 MB
   Load Address: c0008000
   Entry Point:  c0008001
   Contents:
0 e- b* R  n. A! w4 Z5 e% o      Image 0: 7471388 Bytes =  7.1 MB
      Image 1: 24895 Bytes = 24.3 kB
   Verifying Checksum ... OK
## Flattened Device Tree from multi component Image at C0007FC0
) s6 ]/ j( K8 I8 m   Booting using the fdt at 0xc0728128
/ M+ B( ?% ]5 U! x   Loading Multi-File Image ... OK
0 p9 f/ I9 [, u8 I9 |5 rOK
0 m- Z3 G3 q! D- O7 yWARNING: legacy format multi component image overwritten
* o% S! h9 H! \   Loading Device Tree to c3ff6000, end c3fff13e ... OK
8 V# Y" ~+ M4 _* F
0 S  O6 E/ }" W9 ]* TStarting kernel ...

8 q6 i8 ]9 N, L4 m" B- @Booting Linux on physical CPU 0x0
2 _8 Q/ \3 B/ i/ Q5 L# ^# C2 m+ p- PLinux version 4.2.0 (hw@localhost.localdomain) (gcc version 4.4.1 (Sourcery G++ Lite 2010
6 V) W/ g) g/ n. _q1-189) ) #90 Tue Dec 4 03:32:33 EST 2018
$ w( V' @$ K. m" kCPU: ARMv7-M [410fc271] revision 1 (ARMv7M), cr=00000000
5 P9 b0 Q" L8 F: V& }7 R; l& mCPU: WBA data cache, WBA instruction cache
Machine model: EmCraft Systems STM32F7-SOM board
9 g# [& _$ t- C/ TBuilt 1 zonelists in Zone order, mobility grouping on.  Total pages: 16256
9 e8 _5 @1 k- M; T% \Kernel command line: stm32_platform=stm32f7-disco console=ttyS0,115200 panic=10 ip=169.25
# Y. _1 R, @4 ?# `  B& ]4.1.10:169.254.1.2:::stm32f7-disco：eth0：off
PID hash table entries: 256 (order: -2, 1024 bytes)
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
) i6 O3 L1 |# d* kInode-cache hash table entries: 4096 (order: 2, 16384 bytes)
3 b3 v  h/ w: M! ~- q  I& y( {Memory: 56432K/65536K available (2523K kernel code, 181K rwdata, 588K rodata, 4000K init,
' F  q; W" I, N/ z; k- h/ Z# S 111K bss, 9104K reserved, 0K cma-reserved)
Virtual kernel memory layout:
    vector  : 0x00000000 - 0x00001000   (   4 kB)
    fixmap  : 0xffc00000 - 0xfff00000   (3072 kB)
    vmalloc : 0x00000000 - 0xffffffff   (4095 MB)
! B# x  p8 Y8 M5 ~! x: u/ E. c    lowmem  : 0xc0000000 - 0xc4000000   (  64 MB)
! G* `+ D6 j* j" A! ?" U2 w      .text : 0xc0008000 - 0xc0312000   (3112 kB)
- r) Z4 y, A  ?: ~      .init : 0xc0312000 - 0xc06fa000   (4000 kB)
      .data : 0xc06fa000 - 0xc07277c0   ( 182 kB)
       .bss : 0xc072811c - 0xc0743e84   ( 112 kB)
9 S; P' a1 y2 Q8 @3 \NR_IRQS:16 nr_irqs:16 16
/interrupt-controller@40013c00: 24 External IRQs detected
clocksource: arm_system_timer: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 27651335
3 Q( ?, o  Z$ w) V  v7 Q8 ns
ARM System timer initialized as clocksource
/soc/timer@40000000: STM32 clockevent driver initialized (32 bits)
sched_clock: 32 bits at 100 Hz, resolution 10000000ns, wraps every 21474836475000000ns
( G$ I, l, J- E/ @/ [3 v# @$ f; SCalibrating delay loop... 427.62 BogoMIPS (lpj=2138112)
pid_max: default: 4096 minimum: 301
8 D; M" [) g; {) `6 U9 yMount-cache hash table entries: 1024 (order: 0, 4096 bytes)
Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)
devtmpfs: initialized
# K; n( h* G/ u$ U* M1 T8 S) \clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275
0000 ns
4 ]8 [5 P" h, J% }- p8 j6 V. Y; Npinctrl core: initialized pinctrl subsystem
NET: Registered protocol family 16
stm32-pinctrl pin-controller: nbanks = 11
stm32-pinctrl pin-controller: nfunctions = 20
stm32-pinctrl pin-controller: ngroups = 23
stm32-pinctrl pin-controller: GPIOA bank added.
stm32-pinctrl pin-controller: GPIOB bank added.
7 K% M* n7 X4 }4 [  x$ m( Xstm32-pinctrl pin-controller: GPIOC bank added.
9 s, T6 m4 ~* ^/ _4 Y& Sstm32-pinctrl pin-controller: GPIOD bank added.
5 J8 y8 D6 B. [$ F: Dstm32-pinctrl pin-controller: GPIOE bank added.
& j% A$ L( Q8 j" \% V  _stm32-pinctrl pin-controller: GPIOF bank added.
! b3 z( `# ?: o5 \2 h% Astm32-pinctrl pin-controller: GPIOG bank added.
! }1 M5 B+ q' }1 E6 V& M+ G: x/ Qstm32-pinctrl pin-controller: GPIOH bank added.
4 c8 g7 D! u8 v; n0 x' h( [, istm32-pinctrl pin-controller: GPIOI bank added.
) J" S$ ?( Q1 u; [stm32-pinctrl pin-controller: GPIOJ bank added.
. p# }, T4 c& f& i0 Sstm32-pinctrl pin-controller: GPIOK bank added.
stm32-pinctrl pin-controller: Function[0         name:i2c_1,    groups:1]
stm32-pinctrl pin-controller: Function[1         name:i2c_2,    groups:1]
9 D" H. x2 Y- z' ~* F$ {0 x# Y$ M2 Rstm32-pinctrl pin-controller: Function[2         name:i2c_3,    groups:1]
stm32-pinctrl pin-controller: Function[3         name:mac,      groups:2]
stm32-pinctrl pin-controller: Function[4         name:sdio,     groups:1]
; r* U1 G  X4 L: @$ r; D* Gstm32-pinctrl pin-controller: Function[5         name:spi_2,    groups:1]
stm32-pinctrl pin-controller: Function[6         name:spi_4,    groups:1]
stm32-pinctrl pin-controller: Function[7         name:spi_5,    groups:1]
stm32-pinctrl pin-controller: Function[8         name:usart1,   groups:1]
stm32-pinctrl pin-controller: Function[9         name:usart6,   groups:1]
stm32-pinctrl pin-controller: Function[10        name:usart7,   groups:1]
stm32-pinctrl pin-controller: Function[11        name:usb_fs,   groups:1]
stm32-pinctrl pin-controller: Function[12        name:usb_hs,   groups:1]
- z: t  U4 l5 O. {- g, T6 ustm32-pinctrl pin-controller: Function[13        name:can_1,    groups:1]
stm32-pinctrl pin-controller: Function[14        name:adc1_in0_pin,     groups:1]
2 m2 ?1 D9 e3 X9 t; ~stm32-pinctrl pin-controller: Function[15        name:dac_out2_pin,     groups:1]
1 A/ O( C0 |. Y3 I2 o; u  M# Wstm32-pinctrl pin-controller: Function[16        name:ltdc,     groups:1]
" L  c7 M" ~6 |+ y+ ?+ _3 k0 c+ `stm32-pinctrl pin-controller: Function[17        name:sai_2,    groups:1]
! V4 O% r  J% c9 C$ o! W0 T8 m3 Zstm32-pinctrl pin-controller: Function[18        name:i2c_4,    groups:1]
stm32-pinctrl pin-controller: Function[19        name:gpio,     groups:3]
stm32-dma 40026000.dma: STM32 DMA driver registered
stm32-dma 40026400.dma: STM32 DMA driver registered
2 O& B/ F& h7 R, w2 p! u3 p0 _3 MSCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
& Q1 z5 e9 I4 Y$ Y6 f: Ousbcore: registered new device driver usb
soc:phy_hs supply vcc not found, using dummy regulator
soc:phy_fs supply vcc not found, using dummy regulator
pps_core: LinuxPPS API ver. 1 registered
3 R/ ^& v4 t: H& W! fpps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@linux.it>
8 w$ D( J0 r7 t( ?- F) HPTP clock support registered
+ `& `0 M; V& U; `' e, q" gAdvanced Linux Sound Architecture Driver Initialized.
Bluetooth: Core ver 2.20
NET: Registered protocol family 31
Bluetooth: HCI device and connection manager initialized
9 N2 n5 s; H* U. d( a2 e1 p# }6 wBluetooth: HCI socket layer initialized
* g6 {4 t3 ~8 a' e  N8 {. t; H8 }! oBluetooth: L2CAP socket layer initialized
" `$ z& F8 {) o. A  jBluetooth: SCO socket layer initialized
" l2 |6 P/ g# g  Q: @; ~clocksource: Switched to clocksource arm_system_timer
NET: Registered protocol family 2
TCP established hash table entries: 1024 (order: 0, 4096 bytes)
TCP bind hash table entries: 1024 (order: 0, 4096 bytes)
+ _5 c8 O& K1 I0 T4 J5 NTCP: Hash tables configured (established 1024 bind 1024)
UDP hash table entries: 256 (order: 0, 4096 bytes)
5 M4 b4 c- F  C( S2 a: N# LUDP-Lite hash table entries: 256 (order: 0, 4096 bytes)
NET: Registered protocol family 1
RPC: Registered named UNIX socket transport module.
RPC: Registered udp transport module.
. a2 @' S; Q, u, _1 |" }1 bRPC: Registered tcp transport module.
& c, A+ B3 Q3 D: |$ [: Y) ARPC: Registered tcp NFSv4.1 backchannel transport module.
Power Management for STM32
. y! Q* E* }3 j/ T6 o' I6 Bfutex hash table entries: 16 (order: -5, 192 bytes)
8 G! n$ Z) i( g7 q; j5 ]  x8 Ljffs2: version 2.2. (NAND) (SUMMARY)  漏 2001-2006 Red Hat, Inc.
4 [: S& O+ X$ Z4 j7 Dfuse init (API version 7.23)
Block layer SCSI generic (bsg) driver version 0.4 loaded (major 250)
  _( n2 K, Z: Nio scheduler noop registered
1 _) u1 _7 G, Bio scheduler cfq registered (default)
: K* D% M& \* F4 _" jstm32-pinctrl pin-controller: maps: function gpio group pwms num 2
& k- O" `& j, y. xstm32-pwm pwm0: basing on TIM3.1(x16)
stm32-pinctrl pin-controller: maps: function ltdc group ltdc-0 num 29
stm32_lcdfb 40016800.ltdc: fb0: fb device registered successfully
  z+ F$ U* M& v7 \2 k9 SSTM32 USART driver initialized
6 M; j+ E7 s- ?! r) `stm32-pinctrl pin-controller: maps: function usart1 group usart1-0 num 3
" s4 e8 u  X  ^/ m7 F40011000.serial: ttyS0 at MMIO 0x40011000 (irq = 34, base_baud = 6750000) is a stm32-usar
3 s' o  R. k$ H0 k/ y) Bt
$ S: m1 S4 ?2 T7 r' u1 Q( [console [ttyS0] enabled
stm32-pinctrl pin-controller: maps: function usart6 group usart6-0 num 3
40011400.serial: ttyS5 at MMIO 0x40011400 (irq = 35, base_baud = 6750000) is a stm32-usar
t
nbd: registered device at major 43
% q3 F3 G$ V% w3 Cstm32-pinctrl pin-controller: maps: function dac_out2_pin group dac-0 num 2
stm32_dac 40007400.dac: dac1: no timer assigned, DMA functionality is not available
+ W/ Z; [9 E% I# {3 ]stm32_dac 40007400.dac: created 1 character devices with MAJOR 248
2 ofpart partitions found on MTD device physmap-stm-flash.0
Creating 2 MTD partitions on "physmap-stm-flash.0":
0x000000000000-0x000000020000 : "stm_flash_uboot"
0x000000040000-0x000000100000 : "stm_flash_unused"
3 C$ @& j( B' u% Q  A+ S7 J8 hstm32-pinctrl pin-controller: maps: function spi_5 group spi_5-0 num 4
stm32-spi 40015000.spi: SPI Controller 4 at 40015000,irq=38,hz=108000000
CAN device driver interface
stm32-pinctrl pin-controller: maps: function can_1 group can_1-0 num 3
: r* Q: O. b5 M1 B) d, N+ M0 o3 ustm32-can 40006400.can: device registered (reg=40006400, irq=31)
3 `" F7 f$ w4 P9 ?  v2 ?stm32-pinctrl pin-controller: maps: function mac group mac_rmii num 10
stmmac - user ID: 0x10, Synopsys ID: 0x35
Ring mode enabled
4 N- [! Z5 L# Z DMA HW capability register supported
: S9 M( j: }! j$ r, |0 _  k; n Enhanced/Alternate descriptors
2 h. g+ d/ @" i1 x5 c" O        Enabled extended descriptors
. `$ _" Y. v! ? RX Checksum Offload Engine supported (type 2)
6 K8 R+ I; F& \3 I TX Checksum insertion supported
, ~! v1 x) s  O: d: v8 y Wake-Up On Lan supported
6 j  e% C- \* @8 P- \ Enable RX Mitigation via HW Watchdog Timer
+ ]( }1 `8 h9 g+ astm32-dwmac 40028000.ethernet eth0: No MDIO subnode found
7 E* F9 T: n$ @* {libphy: stmmac: probed
eth0: PHY ID 0007c0f1 at 0 IRQ POLL (stmmac-0:00) active
2 v+ F1 g/ Q8 x# c: [PPP generic driver version 2.4.2
" V1 Q$ ^8 I6 Y4 k  M2 HPPP BSD Compression module registered
" w- W& v" D  Y7 j( ?0 ~0 _* R9 o- LPPP Deflate Compression module registered
# f0 o& u  i( `4 j* _# B0 u" nusbcore: registered new interface driver rt2800usb
4 Y2 w) t) r/ n, W6 rstm32-pinctrl pin-controller: maps: function usb_hs group usb_hs-0 num 3
dwc2 40040000.usb: DWC OTG Controller
dwc2 40040000.usb: new USB bus registered, assigned bus number 1
7 S* K$ y# E7 ^6 |dwc2 40040000.usb: irq 56, io mem 0x00000000
usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
; T$ O; E7 i3 ?7 N7 p/ k/ {/ pusb usb1: Product: DWC OTG Controller
usb usb1: Manufacturer: Linux 4.2.0 dwc2_hsotg
usb usb1: SerialNumber: 40040000.usb
hub 1-0:1.0: USB hub found
, j  ^: j0 T9 l4 r3 H# p1 @2 X1 _hub 1-0:1.0: 1 port detected
stm32-pinctrl pin-controller: maps: function usb_fs group usb_fs-0 num 3
' i2 c* Y3 K/ ?: \! ?. X# D! J50000000.usb supply vusb_d not found, using dummy regulator
, L, V& G0 ?( m1 x( d. I3 W5 Z50000000.usb supply vusb_a not found, using dummy regulator
) S1 L- r3 C9 @dwc2 50000000.usb: EPs: 6, dedicated fifos, 512 entries in SPRAM
, r" P9 }7 P: n* N) e  X% zdwc2 50000000.usb: DCFG=0x08200000, DCTL=0x00000002, DIEPMSK=0000000b
dwc2 50000000.usb: GAHBCFG=0x00000000, GHWCFG1=0x00000000
dwc2 50000000.usb: GRXFSIZ=0x000000a0, GNPTXFSIZ=0x004000a0
dwc2 50000000.usb: DPTx[1] FSize=32, StAddr=0x000000e0
dwc2 50000000.usb: DPTx[2] FSize=64, StAddr=0x00000100
dwc2 50000000.usb: DPTx[3] FSize=512, StAddr=0x00000800
7 S' ~& G; X- p/ ?. zdwc2 50000000.usb: DPTx[4] FSize=512, StAddr=0x00000a00
dwc2 50000000.usb: DPTx[5] FSize=512, StAddr=0x00000c00
dwc2 50000000.usb: ep0-in: EPCTL=0x00008000, SIZ=0x00000000, DMA=0x5abee5fb
0 G$ g- T2 w; \) xdwc2 50000000.usb: ep0-out: EPCTL=0x00008000, SIZ=0x00000000, DMA=0x5abee5fb
dwc2 50000000.usb: ep1-in: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
- S  Y& b/ D$ A8 N' N2 n$ @. N5 ?dwc2 50000000.usb: ep1-out: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
! |. m/ E! @% q" J+ ~dwc2 50000000.usb: ep2-in: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
dwc2 50000000.usb: ep2-out: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
% j% F* [9 n" f8 Z+ bdwc2 50000000.usb: ep3-in: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
* N8 J8 N$ a6 I! n3 t, X5 vdwc2 50000000.usb: ep3-out: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
dwc2 50000000.usb: ep4-in: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
dwc2 50000000.usb: ep4-out: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
; S6 x9 |6 Q0 A( o  {dwc2 50000000.usb: ep5-in: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
0 J3 P; t! V2 _; F: sdwc2 50000000.usb: ep5-out: EPCTL=0x00000000, SIZ=0x00000000, DMA=0x5abee5fb
( {+ s; m( p- l& Z8 T8 v2 d  P1 b+ ddwc2 50000000.usb: DVBUSDIS=0x000017d7, DVBUSPULSE=000005b8
. F3 ^9 k2 [# f+ M: @# Yusbcore: registered new interface driver cdc_acm
cdc_acm: USB Abstract Control Model driver for USB modems and ISDN adapters
# u+ P; {1 S1 C, U1 H: musbcore: registered new interface driver uas
usbcore: registered new interface driver usb-storage
6 M2 v* K& m- w2 v' ?9 qg_serial gadget: Gadget Serial v2.4
g_serial gadget: g_serial ready
dwc2 50000000.usb: bound driver g_serial
6 Y" W% M/ w6 yi2c /dev entries driver
stm32-pinctrl pin-controller: maps: function i2c_4 group i2c_4-0 num 3
bmp085 3-0077: Successfully initialized bmp085!
8 q' y9 q* x1 R$ c) w$ Pstm32f7-i2c 40006000.i2c: I2C Controller i2c-3 at 40006000,irq=58
Driver for 1-wire Dallas network protocol.
usbcore: registered new interface driver btusb
5 F& b! h7 W- l2 xstm32-pinctrl pin-controller: maps: function sdio group sdio-0 num 7
6 Y& N- e5 Z1 ~' cmmci-pl18x 40012c00.sdi: Got CD GPIO
mmci-pl18x 40012c00.sdi: mmc0: PL180 manf 80 rev4 at 0x40012c00 irq 37,0 (pio)
: K( o2 w0 ^3 r2 R6 sstm32-dma 40026400.dma: stm32_dma_of_xlate: unable to get channel 3 - was already request
* j( f2 W# y; z6 H2 ~/ T8 G# hed
4 h8 [5 x) ^, O& W6 y+ @mmci-pl18x 40012c00.sdi: DMA channels RX dma1chan3, TX dma1chan3
stm32_gpio_to_irq: Event line 3 now points to fire interrupts from bank G
stm32-pinctrl pin-controller: maps: function gpio group outs num 2
hidraw: raw HID events driver (C) Jiri Kosina
usbcore: registered new interface driver usbhid
usbhid: USB HID core driver
stm32-pinctrl pin-controller: maps: function adc1_in0_pin group adc1-0 num 2
/ v- G/ u1 r; o. H8 j% }stm32f4-adc 40012000.adc: registered
stm32-pinctrl pin-controller: maps: function sai_2 group sai_2-0 num 5
stm32-dma 40026400.dma: stm32_dma_of_xlate: unable to get channel 4 - was already request
ed
0 @; A- N1 o/ [9 Cstm32-asoc-card sound: failed to find codec platform device
2 C6 L( u+ p: B/ Tstm32-asoc-card: probe of sound failed with error -22
% y8 ?8 R9 R7 F  XNET: Registered protocol family 17
can: controller area network core (rev 20120528 abi 9)
NET: Registered protocol family 29
; h* m9 w8 r' X6 R3 Mcan: raw protocol (rev 20120528)
can: broadcast manager protocol (rev 20120528 t)
can: netlink gateway (rev 20130117) max_hops=1
: ^) G8 I* X, TBluetooth: RFCOMM TTY layer initialized
Bluetooth: RFCOMM socket layer initialized
: s& ?1 @! h3 a1 Z3 ^4 C' `0 }" wBluetooth: RFCOMM ver 1.11
hctosys: unable to open rtc device (rtc0)
% \/ O) _, h" i, F1 ?& gvmmc: disabling
  ]0 k! k" U- k( x( B" c, SALSA device list:
: {$ C; J# m- j* \0 L9 E6 r# Q  No soundcards found.
' R- K) r$ r) B' \) OFreeing unused kernel memory: 4000K (c0312000 - c06fa000)
init started: BusyBox v1.24.2 (2018-11-22 20:35:58 EST)
/ # amixer: Mixer attach default error: No such file or directory
. T  S( H  v# F$ N+ _stm32-dwmac 40028000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx

# g, M& r9 G) ?( Z/ u6 C. i/ # free
             total       used       free     shared    buffers     cached
Mem:         60432       8140      52292          0          0       4792
-/+ buffers/cache:       3348      57084
/ #

: k1 V3 i/ E  k$ F
  X( m1 X: i# t# A# z- q

哇哦！