Hi Adrian, Adrian Pop <pop.adrian61@xxxxxxxxx> 于2020年7月19日周日 下午10:54写道: > > Hello Hua, > > Thank you for your review, > > On Tue, Jul 14, 2020 at 6:37 AM Hua Dillon <dillonhua@xxxxxxxxx> wrote: > > > > Hi, Adrian, > > > > Just one suggestion for you. > > > > Adrian Pop <pop.adrian61@xxxxxxxxx> 于2020年7月3日周五 上午1:30写道: > > > > > > STM32f769-disco features a 4" MIPI DSI display: add support for it. > > > On Cortex-M7 DMA can't use cached memory. For this reason I use a dedicated > > > memory pool for DMA with no-cache attribute which is located at the end of > > > RAM. > > > > > > Signed-off-by: Adrian Pop <pop.adrian61@xxxxxxxxx> > > > --- > > > arch/arm/boot/dts/stm32f746.dtsi | 34 +++++++++++++++++++ > > > arch/arm/boot/dts/stm32f769-disco.dts | 49 +++++++++++++++++++++++++++ > > > 2 files changed, 83 insertions(+) > > > > > > diff --git a/arch/arm/boot/dts/stm32f746.dtsi b/arch/arm/boot/dts/stm32f746.dtsi > > > index 93c063796780..577a812ca01c 100644 > > > --- a/arch/arm/boot/dts/stm32f746.dtsi > > > +++ b/arch/arm/boot/dts/stm32f746.dtsi > > > @@ -48,6 +48,19 @@ / { > > > #address-cells = <1>; > > > #size-cells = <1>; > > > > > > + reserved-memory { > > > + #address-cells = <1>; > > > + #size-cells = <1>; > > > + ranges; > > > + > > > + linux,dma { > > > + compatible = "shared-dma-pool"; > > > + linux,dma-default; > > > + no-map; > > > + reg = <0xc0f00000 0x100000>; > > > + }; > > > + }; > > > + > > Christoph Hellwig was submit a patch for !CONFIG_MMU platforms to support mmap. > > the patch is : 1fbf57d05302 dma-direct: re-enable mmap for !CONFIG_MMU > > i thought there is no need to create a reserved-memory for it. > > Just tried with his patch, if I don't have the reserved-memory, I get: > > [drm] Initialized stm 1.0.0 20170330 for 40016800.display-controller on minor 0 > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 5 at arch/arm/mm/dma-mapping-nommu.c:50 0xc000b8e9 > CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.8.0-rc1-next-20200616 #4 > Hardware name: STM32 (Device Tree Support) > Workqueue: events 0xc0150fc1 > > This is the reason I added the reserved memory in the first place. > Oh, sorry, i forget stm32f7 with cache inside. yes, you need a reserve memory for that case. but, "reg = <0xc0f00000 0x100000>;" should big enough for framebuffer, as your know this is a global reserve memory for all devices, it's might need more for other devices, like camera etc. or use per-device reserve memory region. thanks. > > > > > clocks { > > > clk_hse: clk-hse { > > > #clock-cells = <0>; > > > @@ -75,6 +88,27 @@ clk_i2s_ckin: clk-i2s-ckin { > > > }; > > > > > > soc { > > > + ltdc: display-controller@40016800 { > > > + compatible = "st,stm32-ltdc"; > > > + reg = <0x40016800 0x200>; > > > + interrupts = <88>, <89>; > > > + resets = <&rcc STM32F7_APB2_RESET(LTDC)>; > > > + clocks = <&rcc 1 CLK_LCD>; > > > + clock-names = "lcd"; > > > + status = "disabled"; > > > + }; > > > + > > > + dsi: dsi@40016c00 { > > > + compatible = "st,stm32-dsi"; > > > + reg = <0x40016c00 0x800>; > > > + interrupts = <98>; > > > + clocks = <&rcc 1 CLK_F769_DSI>, <&clk_hse>; > > > + clock-names = "pclk", "ref"; > > > + resets = <&rcc STM32F7_APB2_RESET(DSI)>; > > > + reset-names = "apb"; > > > + status = "disabled"; > > > + }; > > > + > > > timer2: timer@40000000 { > > > compatible = "st,stm32-timer"; > > > reg = <0x40000000 0x400>; > > > diff --git a/arch/arm/boot/dts/stm32f769-disco.dts b/arch/arm/boot/dts/stm32f769-disco.dts > > > index 1626e00bb2cb..a9e81b49809c 100644 > > > --- a/arch/arm/boot/dts/stm32f769-disco.dts > > > +++ b/arch/arm/boot/dts/stm32f769-disco.dts > > > @@ -153,3 +153,52 @@ &usbotg_hs { > > > pinctrl-names = "default"; > > > status = "okay"; > > > }; > > > + > > > +&dsi { > > > + #address-cells = <1>; > > > + #size-cells = <0>; > > > + status = "okay"; > > > + > > > + ports { > > > + #address-cells = <1>; > > > + #size-cells = <0>; > > > + > > > + port@0 { > > > + reg = <0>; > > > + dsi_in: endpoint { > > > + remote-endpoint = <<dc_out_dsi>; > > > + }; > > > + }; > > > + > > > + port@1 { > > > + reg = <1>; > > > + dsi_out: endpoint { > > > + remote-endpoint = <&dsi_in_panel>; > > > + }; > > > + }; > > > + > > > + }; > > > + > > > + panel: panel { > > > + compatible = "orisetech,otm8009a"; > > > + reg = <0>; > > > + reset-gpios = <&gpioj 15 GPIO_ACTIVE_LOW>; > > > + status = "okay"; > > > + > > > + port { > > > + dsi_in_panel: endpoint { > > > + remote-endpoint = <&dsi_out>; > > > + }; > > > + }; > > > + }; > > > +}; > > > + > > > +<dc { > > > + status = "okay"; > > > + > > > + port { > > > + ltdc_out_dsi: endpoint { > > > + remote-endpoint = <&dsi_in>; > > > + }; > > > + }; > > > +}; > > > -- > > > 2.27.0 > > > > > > > > > _______________________________________________ > > > linux-arm-kernel mailing list > > > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > > Regards, > Adrian