From mboxrd@z Thu Jan  1 00:00:00 1970
From: lists@kaiser.cx (Martin Kaiser)
Date: Wed, 1 Aug 2018 09:59:25 +0200
Subject: how to best ioremap() the ranges part of a "simple-bus" device?
In-Reply-To: <20180731102449.Horde.1z7io_6Z3o-YiVoMcjWtBTc@crashcourse.ca>
References: <20180731102449.Horde.1z7io_6Z3o-YiVoMcjWtBTc@crashcourse.ca>
Message-ID: <20180801075925.vywifrbmpz77mkh2@viti.kaiser.cx>
To: kernelnewbies@lists.kernelnewbies.org
List-Id: kernelnewbies.lists.kernelnewbies.org

Thus wrote rpjday at crashcourse.ca (rpjday at crashcourse.ca):


> i'll need to access that device tree entry and effectively ioremap()
> slave0's physical address to a usable virtual address.

>   is there a canonical way to do this? short of manually extracting
> the appropriate device tree node and reading that property and calling
> ioremap()? is there a wrapper for that sort of operation, which i
> imagine must be fairly common?

I guess that of_iomap() does what you need here.

>   oh, and a pointer to a good example in the current kernel source
> would, of course, be useful.

cm_init() in arch/arm/mach-integrator/core.c searches a dt node and does
maps its address space. If you search for of_iomap() in the sources,
you'll find plenty of other examples.