From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:49774) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ScJWR-0002VO-6q for qemu-devel@nongnu.org; Wed, 06 Jun 2012 12:55:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ScJWL-0000Iz-2B for qemu-devel@nongnu.org; Wed, 06 Jun 2012 12:55:50 -0400 Message-ID: <4FCF8B88.9000302@freescale.com> Date: Wed, 6 Jun 2012 11:55:36 -0500 From: Scott Wood MIME-Version: 1.0 References: <1338940402-28502-1-git-send-email-agraf@suse.de> <1338940402-28502-8-git-send-email-agraf@suse.de> <1338959908.15420.17.camel@PetaLogix-ws2> <4FCF7E92.4060207@suse.de> In-Reply-To: <4FCF7E92.4060207@suse.de> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 07/31] dt: add helper for phandle allocation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf Cc: Peter Crosthwaite , qemu-ppc Mailing List , "qemu-devel@nongnu.org Developers" On 06/06/2012 11:00 AM, Alexander Graf wrote: > On 06/06/2012 07:18 AM, Peter Crosthwaite wrote: >> On Wed, 2012-06-06 at 01:52 +0200, Alexander Graf wrote: >>> Phandle references work by having 2 pieces: >>> >>> - a "phandle" 1-cell property in the device tree node >>> - a reference to the same value in a property we want to point >>> to the other node >>> >>> To generate the 1-cell property, we need an allocation mechanism that >>> gives us a unique number space. This patch adds an allocator for these >>> properties. >>> >>> Signed-off-by: Alexander Graf >>> --- >>> device_tree.c | 7 +++++++ >>> device_tree.h | 1 + >>> 2 files changed, 8 insertions(+), 0 deletions(-) >>> >>> diff --git a/device_tree.c b/device_tree.c >>> index d4f1f0a..317bdd0 100644 >>> --- a/device_tree.c >>> +++ b/device_tree.c >>> @@ -220,6 +220,13 @@ int qemu_devtree_setprop_phandle(void *fdt, >>> const char *node_path, >>> return qemu_devtree_setprop_cell(fdt, node_path, property, >>> phandle); >>> } >>> >>> +uint32_t qemu_devtree_alloc_phandle(void *fdt) >>> +{ >>> + static int phandle = 0x8000; >> can easily double check for duplicates. Would also allow you to start >> from 1 rather than magic number 0x8000? You can't check for duplicates, because the tree fragments you'll be conflicting with haven't been added to the tree yet. That's done by a tool operating on the tree output by the first pass of qemu, and is fed back into the second pass of qemu. -Scott