Kindle Paperwhite Microprocessor

atleon · 11-07-2012, 06:58 PM

Hi guys, I've been looking for this info without luck. Does anyone know the speed of the micro of the Kindle Paperwhite? I know that for Touch and Kindle 4 it works at 800MHz....

twobob · 11-08-2012, 08:46 PM

Rather than scrabbling around for answers or ripping the case apart, this should be proof enough if the processor is identical (which it is I think BTW)

assuming you have ssh access... (or someone with a non nerfed PW)

we could do a rough side by side (meh, I could build a better tool but meh) https://www.mobileread.com/forums/sho...d.php?t=188491

Let's run a benchmark

(the what script is my own making)

K3:

Quote:

[root@kindle root]# what
Kindle 3!
[root@kindle us]# ./benchmark.sh
Spoiler:

MD5 : 9639 Kb/s, 0 cycles/byte

Spoiler:

K5:

Quote:

[root@kindle root]# what
Kindle 5!
[root@kindle root]#benchmark.sh

MD5 : 22199 Kb/s, 0 cycles/byte

Spoiler:

PW: ?
feel free to check it out

HTH

This was also a handy test of the lib loader script

Works fine on a 3/4/5/PW too. great.

knc1 · 11-08-2012, 09:02 PM

cat /proc/cpuinfo will give you the basic clock and bogo mips numbers.

Of additional interest is the clock speed controls and governor settings. Which you can find in the /sys sub-tree.
It will be among the other power and clock management stuff.

twobob · 11-08-2012, 09:05 PM

Quote:

Originally Posted by knc1

cat /proc/cpuinfo will give you the basic clock and bogo mips numbers.

Of additional interest is the clock speed controls and governor settings. Which you can find in the /sys sub-tree.
It will be among the other power and clock management stuff.

hehehe. but where's the fun

5:
[root@kindle root]# cat /proc/cpuinfo

Quote:

Processor : ARMv7 Processor rev 5 (v7l)
BogoMIPS : 159.90
Features : swp half thumb fastmult vfp edsp neon vfpv3
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x2
CPU part : 0xc08
CPU revision : 5

Yours will be the same as that atleon I would imagine.

knc1 · 11-08-2012, 09:31 PM

There should have been a cpu clock speed in that file also.

Generally, bogo mips * 2 == cpu speed, which in this case would be about 400Mhz.
Which is known to not be the maximum.

The most likely reason is that the Kindle was not setup to boot at maximum clock speed.

You can get better information out of the /sys tree -
Such as the limits of the clock speed, changing the clock speed, changing the governor in use, etc. etc. etc.

twobob · 11-08-2012, 11:01 PM

Quote:

Originally Posted by K5

max
800000

min
60000

/sys/devices/system/cpu/cpu0/cpufreq/driver
imx

Quote:

Originally Posted by K3

max
512000

min
256000

/sys/devices/system/cpu/cpu0/cpufreq/driver
MX35

better info spewed

geekmaster · 11-08-2012, 11:05 PM

The kindle clock speed is optimized for extended battery life, but can be adjusted for processor intensive apps. Like laptops and netbooks, current (or future) firmware may automatically adjust to a higher clock speed when connected to a power adapter.

To run a benchmark app, I would call it from a script that wraps governor pokes around it, and perhaps show results for max speed, default speed, and perhaps minimum speed.

Beware that the kindle is not designed with adequate cooling to run the processor flat-out at max speed for long time periods.

knc1 · 11-08-2012, 11:13 PM

And if you check, it probably has the "conservative" governor enabled.

Often the kernel will have more than one of the governors available, you should be able to get a list of the ones available in that general area of the system tree.

You can also switch governors by writing instead of reading the "current xxx" (forgot the name) entry.

As you browse with ls -l, keep an eye open for the things that are write enabled, you can change all of those.

PS: Yes, all of this goes towards an answer of the question asked:
"Under what conditions?" should have been included in the question.
The answer is: 60Mhz ... 800Mhz, depending on ..., which is a very large range.

(I think the minimum on the SoC is a few hundred Khz - but the kernel may not run that slow - you may have to check the "power" part of the sys cpu tree - look for a "sleep" entry (or some such) - that will slow it way down, but you may have to re-boot to wake it up.)

atleon · 11-09-2012, 03:28 AM

Thank all of you for your answers. The fact is that I don't have the Paperwhite yet so I couldn't run any benchmark. I was asking about the maximun frequency it could work. You can find that KoboGlo is capable to run at 1GHz according to the specs:

http://www.kobo.com/koboglo/techspecs/

knc1 · 11-09-2012, 07:00 AM

Quote:

Originally Posted by atleon

Thank all of you for your answers. The fact is that I don't have the Paperwhite yet so I couldn't run any benchmark. I was asking about the maximun frequency it could work. You can find that KoboGlo is capable to run at 1GHz according to the specs:

http://www.kobo.com/koboglo/techspecs/

Why not look that up on the Freescale site?
Freescale is the place to find technical specifications on the SoC.

NiLuJe · 11-09-2012, 09:16 AM

The Touch/PW defaults to the ondemand cpufreq governor, IIRC.

dos1 · 11-09-2012, 09:29 AM

Quote:

Originally Posted by NiLuJe

The Touch/PW defaults to the ondemand cpufreq governor, IIRC.

Indeed it does, in /etc/upstart/system.conf

Code:

# Set the cpu governor speed to ondemand
  echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

knc1 · 11-09-2012, 09:29 AM

Quote:

Originally Posted by NiLuJe

The Touch/PW defaults to the ondemand cpufreq governor, IIRC.

Durn kernel terminology - I keep losing track;
"ondemand" is more conservative of battery power than "conservative" -
So I stand corrected.

O.P:
The "maximum clock speed" of the SoC and that allowed by the kernel governor is not the same.
Which "maximum" do you want?

We can answer your question if you don't give us such an open ended one.

Translation:
If you want a specific answer, ask a specific question.

atleon · 11-09-2012, 01:57 PM

Quote:

Originally Posted by knc1

Why not look that up on the Freescale site?
Freescale is the place to find technical specifications on the SoC.

Because I don't know the Freescale CI that the Paperwhite uses. In fact I didn't even know that it was Freescale. In Kobo site consumers can read:

Processor: 1GHz.

I just wanted to know the same information for the Paperwhite as you cannot find it in Amazon site.

knc1 · 11-09-2012, 02:05 PM

iMX508 - it is the only one with the built-in e-ink controller.

http://cache.freescale.com/files/32b...EC.pdf?pspll=1
Section 1.2: 800Mhz core.

11-07-2012, 06:58 PM	#1
atleon Enthusiast Posts: 48 Karma: 60414 Join Date: Nov 2012 Device: Kindle Paperwhite	Kindle Paperwhite Microprocessor Hi guys, I've been looking for this info without luck. Does anyone know the speed of the micro of the Kindle Paperwhite? I know that for Touch and Kindle 4 it works at 800MHz....

11-08-2012, 11:05 PM	#7
geekmaster Carpe diem, c'est la vie. Posts: 6,433 Karma: 10773668 Join Date: Nov 2011 Location: Multiverse 6627A Device: K1 to PW3	The kindle clock speed is optimized for extended battery life, but can be adjusted for processor intensive apps. Like laptops and netbooks, current (or future) firmware may automatically adjust to a higher clock speed when connected to a power adapter. To run a benchmark app, I would call it from a script that wraps governor pokes around it, and perhaps show results for max speed, default speed, and perhaps minimum speed. Beware that the kindle is not designed with adequate cooling to run the processor flat-out at max speed for long time periods. Last edited by geekmaster; 11-08-2012 at 11:12 PM.

11-08-2012, 11:13 PM	#8
knc1 Going Viral Posts: 17,212 Karma: 18210809 Join Date: Feb 2012 Location: Central Texas Device: No K1, PW2, KV, KOA	And if you check, it probably has the "conservative" governor enabled. Often the kernel will have more than one of the governors available, you should be able to get a list of the ones available in that general area of the system tree. You can also switch governors by writing instead of reading the "current xxx" (forgot the name) entry. As you browse with ls -l, keep an eye open for the things that are write enabled, you can change all of those. PS: Yes, all of this goes towards an answer of the question asked: "Under what conditions?" should have been included in the question. The answer is: 60Mhz ... 800Mhz, depending on ..., which is a very large range. (I think the minimum on the SoC is a few hundred Khz - but the kernel may not run that slow - you may have to check the "power" part of the sys cpu tree - look for a "sleep" entry (or some such) - that will slow it way down, but you may have to re-boot to wake it up.) Last edited by knc1; 11-08-2012 at 11:19 PM.

11-09-2012, 03:28 AM	#9
atleon Enthusiast Posts: 48 Karma: 60414 Join Date: Nov 2012 Device: Kindle Paperwhite	Thank all of you for your answers. The fact is that I don't have the Paperwhite yet so I couldn't run any benchmark. I was asking about the maximun frequency it could work. You can find that KoboGlo is capable to run at 1GHz according to the specs: http://www.kobo.com/koboglo/techspecs/ Last edited by atleon; 11-09-2012 at 03:33 AM.

11-09-2012, 02:05 PM	#15
knc1 Going Viral Posts: 17,212 Karma: 18210809 Join Date: Feb 2012 Location: Central Texas Device: No K1, PW2, KV, KOA	iMX508 - it is the only one with the built-in e-ink controller. http://cache.freescale.com/files/32b...EC.pdf?pspll=1 Section 1.2: 800Mhz core. Last edited by knc1; 11-09-2012 at 02:34 PM.

11-08-2012, 09:02 PM	#3
knc1 Going Viral Posts: 17,212 Karma: 18210809 Join Date: Feb 2012 Location: Central Texas Device: No K1, PW2, KV, KOA	cat /proc/cpuinfo will give you the basic clock and bogo mips numbers. Of additional interest is the clock speed controls and governor settings. Which you can find in the /sys sub-tree. It will be among the other power and clock management stuff.

11-08-2012, 09:31 PM	#5
knc1 Going Viral Posts: 17,212 Karma: 18210809 Join Date: Feb 2012 Location: Central Texas Device: No K1, PW2, KV, KOA	There should have been a cpu clock speed in that file also. Generally, bogo mips * 2 == cpu speed, which in this case would be about 400Mhz. Which is known to not be the maximum. The most likely reason is that the Kindle was not setup to boot at maximum clock speed. You can get better information out of the /sys tree - Such as the limits of the clock speed, changing the clock speed, changing the governor in use, etc. etc. etc.

11-09-2012, 09:16 AM	#11
NiLuJe BLAM! Posts: 13,506 Karma: 26047190 Join Date: Jun 2010 Location: Paris, France Device: Kindle 2i, 3g, 4, 5w, PW, PW2, PW5; Kobo H2O, Forma, Elipsa, Sage, C2E	The Touch/PW defaults to the ondemand cpufreq governor, IIRC.

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