From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Heiko Stuebner To: Randy Li Cc: linux-rockchip@lists.infradead.org, mturquette@baylibre.com, sboyd@codeaurora.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] clk: rockchip: rk3288: prefer vdpu for vcodec clock source Date: Sun, 14 May 2017 17:06:19 +0200 Message-ID: <2067155.b6jtcnMS5V@phil> In-Reply-To: <20170514065009.3047-1-ayaka@soulik.info> References: <20170514065009.3047-1-ayaka@soulik.info> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" List-ID: Hi Randy, Am Sonntag, 14. Mai 2017, 14:50:09 CEST schrieb Randy Li: > The RK3288 CRU system clock solution would suggest use > the vdpu clock source for the VPU(aclk_vpu and hclk_vpu). > > Reading the registers of VPU(both VEPU and VDPU) would become all high > when the vepu is used as the clock source. It may be a bug in the SoC, > not sure whether it is fixed at RK3288W. I don't think that is a case of "preference". GRF_SOC_CON0[7] indicates that value 0 means vepu gets selected as vcodec clock and value 1 means vdpu gets selected as vcodec. The array values below are supposed to match these values, so array index 0 represents the clock for value 0 and so on. So this is really only a description of the hardware clock layout. If you want to actually switch the mux value, please assign the vcodec clock an id and use the assigned-clocks mechanism in the devicetree. Heiko