I was assigned to get newer kernel version working in TI OMAP l138 LCDK. I used BuildRoot 2015.05 stable release to start with. The kernel image booted and root file system were compiled and running on it, but somehow I couldn't get CPU Frequency Scaling working in Kernel 3.18.19, which I neither find /sys/devices/system/cpu/cpu0/cpufreq directory nor I can see any information related to CPU frequency in /proc/cpuinfo. I searched on google for a week but I couldn't find any answers.
I use BuildRoot 2015.05 and built with linux-devkit in ti-sdk-omapl138-lcdk-01.00.00 under ubuntu 14.04
U-Boot 2010.12 (May 07 2012 - 16:09:45)
kernel compile options:
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System Type --->
ARM system type (TI DaVinci) --->
TI DaVinci Implementations --->
*** DaVinci Core Type ***
[*] DA850/OMAP-L138/AM18x based system
*** DaVinci Board Type ***
[*] TI DA850/OMAP-L138/AM18x Reference Platform
Select peripherals connected to expander on UI board (No peripheral is enabled) --->
[*] TI AM1808 / OMAPL-138 Hawkboard platform
[*] DAVINCI multiplexing support
[*] Multiplexing debug output
[*] Warn about pins the bootloader didn't set up
[*] CPU Frequency scaling
<M> CPU frequency translation statistics
[*] CPU frequency translation statistics details
Default CPUFreq governor (userspace) --->
<M> 'performance' governor
<M> 'powersave' governor
-*- 'userspace' governor for userspace frequency scaling
<M> 'ondemand' cpufreq policy governor
<M> 'conservative' cpufreq governor
<M> Generic DT based cpufreq driver
ARM CPU frequency scaling drivers ----
[*] CPU idle PM support
[*] Ladder governor (for periodic timer tick)
-*- Menu governor (for tickless system)
ARM CPU Idle Drivers ----
Device Drivers --->
Multifunction device drivers --->
<*> TI TPS6507x Power Management / Touch Screen chips
[*] Voltage and Current Regulator Support --->
<*> TI TPS6507X Power regulators
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u-boot parameters:
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setenv serverip 192.168.100.32
setenv ipaddr 192.168.100.201
setenv bootfile /uImage
setenv kernel_addr_r 0xc0700000
setenv rootpath /rootfs
setenv bootargs console=ttyS2,115200n8 root=/dev/nfs nfsroot=${serverip}:${rootpath},nolock,nfsvers=3 rw mem=128M ip=dhcp eth=${ethaddr}
setenv net_nfs 'tftp ${kernel_addr_r} ${bootfile}; bootm ${kernel_addr_r}'
run net_nfs
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Boot message:
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Booting Linux on physical CPU 0x0
Linux version 3.18.19 (root@3a6f99f89e2b) (gcc version 4.5.3 20110311 (prerelease) (GCC) ) #1 PREEMPT Mon Jul 27 03:31:36 UTC 2015
CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=0005317f
CPU: VIVT data cache, VIVT instruction cache
Machine: AM18x/OMAP-L138 Hawkboard
da8xx_rproc_reserve_cma: 'rproc_mem=nn@address' badly specified
'nn' and 'address' must both be non-zero
Memory policy: Data cache writethrough
DaVinci da850/omap-l138/am18x variant 0x1
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 32512
Kernel command line: console=ttyS2,115200n8 root=/dev/nfs nfsroot=192.168.100.32:/rootfs,nolock,nfsvers=3 rw mem=128M ip=dhcp eth=00:00:a0:00:fb:c7
PID hash table entries: 512 (order: -1, 2048 bytes)
Dentry cache hash table entries: 16384 (order: 4, 65536 bytes)
Inode-cache hash table entries: 8192 (order: 3, 32768 bytes)
Memory: 123920K/131072K available (4030K kernel code, 232K rwdata, 1316K rodata, 188K init, 184K bss, 7152K reserved)
Virtual kernel memory layout:
vector : 0xffff0000 - 0xffff1000 ( 4 kB)
fixmap : 0xffc00000 - 0xffe00000 (2048 kB)
vmalloc : 0xc8800000 - 0xff000000 ( 872 MB)
lowmem : 0xc0000000 - 0xc8000000 ( 128 MB)
modules : 0xbf000000 - 0xc0000000 ( 16 MB)
.text : 0xc0008000 - 0xc0540efc (5348 kB)
.init : 0xc0541000 - 0xc0570000 ( 188 kB)
.data : 0xc0570000 - 0xc05aa240 ( 233 kB)
.bss : 0xc05aa240 - 0xc05d82f4 ( 185 kB)
SLUB: HWalign=32, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
Preemptible hierarchical RCU implementation.
NR_IRQS:245
sched_clock: 32 bits at 24MHz, resolution 41ns, wraps every 178956969942ns
Console: colour dummy device 80x30
Calibrating delay loop... 227.32 BogoMIPS (lpj=1136640)
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 1024 (order: 0, 4096 bytes)
Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes)
CPU: Testing write buffer coherency: ok
Setting up static identity map for 0xc03f6138 - 0xc03f6190
devtmpfs: initialized
pinctrl core: initialized pinctrl subsystem
regulator-dummy: no parameters
NET: Registered protocol family 16
DMA: preallocated 256 KiB pool for atomic coherent allocations
cpuidle: using governor ladder | NOR | Minicom 2.7 | VT102 | 離線 | ttyUSB0 cpuidle: using governor menu
EMAC: MII PHY configured
MUX: initialized GPIO3_12
MUX: Setting register GPIO3_12
PINMUX7 (0x0000001c) = 0x10110110 -> 0x10118110
MUX: initialized GPIO3_13
MUX: Setting register GPIO3_13
PINMUX7 (0x0000001c) = 0x10118110 -> 0x10118810
MUX: initialized GPIO2_4
MUX: Setting register GPIO2_4
PINMUX6 (0x00000018) = 0x00000000 -> 0x00008000
MUX: initialized GPIO6_13
MUX: Setting register GPIO6_13
PINMUX13 (0x00000034) = 0x00000000 -> 0x00000800
edma-dma-engine edma-dma-engine.0: TI EDMA DMA engine driver
edma-dma-engine edma-dma-engine.1: TI EDMA DMA engine driver
SCSI subsystem initialized
usbcore: registered new interface driver usbfs
usbcore: registered new interface driver hub
usbcore: registered new device driver usb
Advanced Linux Sound Architecture Driver Initialized.
Switched to clocksource timer0_1
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)
TCP: Hash tables configured (established 1024 bind 1024)
TCP: reno registered
UDP hash table entries: 256 (order: 0, 4096 bytes)
UDP-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.
RPC: Registered tcp transport module.
RPC: Registered tcp NFSv4.1 backchannel transport module.
futex hash table entries: 256 (order: -1, 3072 bytes)
ntfs: driver 2.1.31 [Flags: R/O].
msgmni has been set to 242
io scheduler noop registered (default)
Serial: 8250/16550 driver, 3 ports, IRQ sharing disabled
serial8250.0: ttyS0 at MMIO 0x1c42000 (irq = 25, base_baud = 14250000) is a 16550A
serial8250.1: ttyS1 at MMIO 0x1d0c000 (irq = 53, base_baud = 9375000) is a 16550A
console [ttyS2] disabled
serial8250.2: ttyS2 at MMIO 0x1d0d000 (irq = 61, base_baud = 9375000) is a 16550A
console [ttyS2] enabled
brd: module loaded
davinci_mdio davinci_mdio.0: davinci mdio revision 1.5
davinci_mdio davinci_mdio.0: detected phy mask ffffff7f
libphy: davinci_mdio.0: probed
davinci_mdio davinci_mdio.0: phy[7]: device davinci_mdio-0:07, driver unknown
i2c /dev entries driver
davinci_mmc da830-mmc.0: Using DMA, 4-bit mode
usbcore: registered new interface driver usbhid
usbhid: USB HID core driver
remoteproc0: dsp is available
remoteproc0: Note: remoteproc is still under development and considered experimental.
remoteproc0: THE BINARY FORMAT IS NOT YET FINALIZED, and backward compatibility isn't yet guaranteed.
remoteproc0: Direct firmware load for rproc-dsp-fw failed with error -2
remoteproc0: failed to load rproc-dsp-fw
no UART detected at 0x1
specify port
snd_mpu401: probe of snd_mpu401.0 failed with error -22
usbcore: registered new interface driver snd-usb-audio
TCP: cubic registered
NET: Registered protocol family 17
console [netcon0] enabled
netconsole: network logging started
davinci_emac davinci_emac.1: using random MAC addr: 4e:37:fc:28:45:1e
drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
davinci_mdio davinci_mdio.0: resetting idled controller
net eth0: attached PHY driver [Generic PHY] (mii_bus:phy_addr=davinci_mdio-0:07, id=7c0f1)
davinci_emac davinci_emac.1 eth0: Link is Up - 100Mbps/Full - flow control rx/tx
Sending DHCP requests ., OK
IP-Config: Got DHCP answer from 192.168.100.1, my address is 192.168.100.95
IP-Config: Complete:
device=eth0, hwaddr=4e:37:fc:28:45:1e, ipaddr=192.168.100.95, mask=255.255.255.0, gw=192.168.100.1
host=192.168.100.95, domain=, nis-domain=(none)
bootserver=0.0.0.0, rootserver=192.168.100.32, rootpath=
nameserver0=192.168.1.252
ALSA device list:
#0: Loopback 1
VFS: Mounted root (nfs filesystem) on device 0:13.
devtmpfs: mounted
Freeing unused kernel memory: 188K (c0541000 - c0570000)
Starting logging: OK
Initializing random number generator... urandom start: failed.
done.
Starting system message bus: random: dbus-uuidgen urandom read with 37 bits of entropy available
Failed to start message bus: The pid file "/var/run/messagebus.pid" exists, if the message bus is not running, remove this file
done
Starting network...
/bin/sh: run-parts: not found
/usr/sbin/avahi-daemon: error while loading shared libraries: libcap.so.2: cannot open shared object file: No such file or directory
/usr/sbin/avahi-daemon: error while loading shared libraries: libcap.so.2: cannot open shared object file: No such file or directory
Welcome to Buildroot
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cat /proc/cpuinfo
processor : 0
model name : ARM926EJ-S rev 5 (v5l)
BogoMIPS : 227.32
Features : swp half thumb fastmult edsp java
CPU implementer : 0x41
CPU architecture: 5TEJ
CPU variant : 0x0
CPU part : 0x926
CPU revision : 5
Hardware : AM18x/OMAP-L138 Hawkboard
Revision : 0000
Serial : 0000000000000000
