Hi Baruch, > -----Original Message----- > From: Baruch Siach [mailto:baruch@xxxxxxxxxx] > Sent: 2015年4月29日 10:25 > To: Wang Shenwei-B38339 > Cc: shawn.guo@xxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 1/1] ARM: imx: make the imx timer driver implementation > independent of SoCs. > > Hi Shenwei Wang, > On Wed, Apr 29, 2015 at 03:19:19PM +0000, Shenwei Wang wrote: > > > -----Original Message----- > > > From: Baruch Siach [mailto:baruch@xxxxxxxxxx] > > > Sent: 2015年4月29日 10:08 > > > To: Wang Shenwei-B38339 > > > Cc: shawn.guo@xxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; > > > devicetree@xxxxxxxxxxxxxxx > > > Subject: Re: [PATCH 1/1] ARM: imx: make the imx timer driver > > > implementation independent of SoCs. > > > > > > When several SoC share the same IP block the usual convention is to > > > name it in the compatible property string after the first SoC it > > > appeared on. Just look at some binding documentation from > > > Documentation/devicetree/bindings/timer/ to find examples. The > > > allwinner,sun5i-a13-hstimer property is shared by A10s and > > > A13 SoCs. The amlogic,meson6-timer is shared by Meson6 and Meson8 > > > SoCs, and so on. > > > > If the same IP block is shared with several SoCs, why we gave them > > different compatible strings? If no changes in an IP block, I assume no changes > in the relating driver as well. > > In this assumption, I don't see any need to introduce a new compatible > > string for an unchanged IP block in a new SoC. > > That is exactly what I meant to say. Sorry that I was not clear enough. > > When the same IP block is used in a newer generation SoC the same compatible > property string is used. For that reason you can find in sun5i-a10s.dtsi the line > > compatible = "allwinner,sun5i-a13-hstimer"; > That is what has been supported in this patch. Besides that, it can also support different IP block versions in a SoC with different revision. For example, Let's say: hstimer version 1 in A13 revision 1.0 hstimer version 2 in A13 revision 1.1 Shenwei > baruch > > -- > http://baruch.siach.name/blog/ ~. .~ Tk Open > Systems > =}------------------------------------------------ooO--U--Ooo------------{= > - baruch@xxxxxxxxxx - tel: +972.2.679.5364, http://www.tkos.co.il - ��.n��������+%������w��{.n����z�{��ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
