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From: Richard Miller <9fans@hamnavoe.com>
To: 9fans@9fans.net
Subject: Re: [9fans] raspberry pi 4 arm64 test image
Date: Thu, 22 Aug 2019 08:07:25 +0100	[thread overview]
Message-ID: <8cad36b2833c37206e385b368fc2e793@hamnavoe.com> (raw)
In-Reply-To: <3468103FF6FA1E43500C7F1B15610D60@felloff.net>

> oh dear. i dont even know the expected physical memory map...
> i guess that ram is continuous block at [0-0xfc000000). but
> some memory might be reserved...

No, the framebuffer is always reserved at the top of the
first 1GB, so on 2GB and 4GB units there are two separate
regions.

> - atags
> - device tree /memory/reg property
> - firmware property request (getramsize() in vcore.c)
> 
> for me getramsize() returns zero for both base and limit so its
> completely useless.

That's strange, getramsize works on my 2GB pi4:
	getramsize 0 1046478848

The same values are in atags (you need 'device_tree=' in config.txt
to make the firmware pass atags instead of devicetree).




  parent reply	other threads:[~2019-08-22  7:07 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-21 21:59 cinap_lenrek
2019-08-21 22:18 ` Bakul Shah
2019-08-22  7:07 ` Richard Miller [this message]
2019-08-22  8:58   ` Steve Simon
2019-08-22 20:26     ` Charles Forsyth
  -- strict thread matches above, loose matches on Subject: below --
2019-08-23 20:15 cinap_lenrek
2019-08-21 23:58 cinap_lenrek
2019-08-22  4:37 ` Bakul Shah
2019-08-21 22:24 cinap_lenrek
2019-08-21 21:35 cinap_lenrek
2019-08-21 19:53 cinap_lenrek
2019-08-21 20:02 ` Richard Miller
2019-08-21 22:20 ` Bakul Shah
2019-08-21 17:56 cinap_lenrek
2019-08-21 19:20 ` Bakul Shah
2019-08-21 19:25   ` Richard Miller
2019-08-21 20:05   ` Richard Miller
2019-08-21 20:27     ` Bakul Shah
2019-08-21 19:57 ` Richard Miller

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