Re: [PATCH] imx: dts: tbs2910: add u-boot dtsi to shrink image size

On 12/6/19 8:26 PM, Soeren Moch wrote:

On 06.12.19 19:43, Tom Rini wrote:

...

On Fri, Dec 06, 2019 at 07:30:47PM +0100, Anatolij Gustschin wrote:

...

Use U-Boot specific board dtsi to remove some not used nodes and properties. With this change applied considerable size reduction has been observed:

$ ./tools/buildman/buildman -b tbs2910 -f tbs2910 || \ ./tools/buildman/buildman -b tbs2910 -sS tbs2910 ... Summary of 2 commits for 1 boards (1 thread, 12 jobs per thread) 01: Merge branch '2019-12-05-master-imports' arm: w+ tbs2910 02: imx: dts: tbs2910: add u-boot dtsi to shrink image size arm: (for 1/1 boards) all -24448.0 text -24448.0

Signed-off-by: Anatolij Gustschin agust@denx.de

This patch was only build-tested, maybe this removes to much and needs some tweaking. I'd appreciate if someone could test it on actual hardware and finish the work, so we hopefully can solve frequent CI build breakage caused by this target.

arch/arm/dts/imx6q-tbs2910-u-boot.dtsi | 219 +++++++++++++++++++++++++ 1 file changed, 219 insertions(+) create mode 100644 arch/arm/dts/imx6q-tbs2910-u-boot.dtsi

diff --git a/arch/arm/dts/imx6q-tbs2910-u-boot.dtsi b/arch/arm/dts/imx6q-tbs2910-u-boot.dtsi new file mode 100644 index 0000000000..3e9307f17f --- /dev/null +++ b/arch/arm/dts/imx6q-tbs2910-u-boot.dtsi @@ -0,0 +1,219 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*

• • U-Boot specific modifications for original tbs2910 DTS.
• • This drops not used nodes/properties to reduce the image size.
• */

+/ {

• /delete-property/ model;
• /delete-property/ compatible;
• aliases {

• /delete-property/ can0;
  

• /delete-property/ can1;
  

• /delete-property/ gpio3;
  

• /delete-property/ gpio4;
  

• /delete-property/ gpio5;
  

• /delete-property/ ipu1;
  

• /delete-property/ mmc3;
  

• /delete-property/ spi0;
  

• /delete-property/ spi1;
  

• /delete-property/ spi2;
  

• /delete-property/ spi3;
  

• /delete-property/ spi4;
  

• /delete-property/ serial2;
  

• /delete-property/ serial3;
  

• /delete-property/ serial4;
  

• /delete-property/ video1;
  

• };
• /delete-node/ cpus;
• /delete-node/ capture-subsystem;
• /delete-node/ chosen;
• /delete-node/ display-subsystem;
• /delete-node/ fan;
• /delete-node/ ir_recv;
• /delete-node/ leds;
• /delete-node/ memory;
• /delete-node/ sound-sgtl5000;
• /delete-node/ sound-spdif;
• soc {

• u-boot,dm-pre-reloc;
  

• /delete-property/ ranges;
  

• /delete-node/ timer@a00600;
  

• aips-bus@2000000 {
  

• 	/delete-property/ ranges;
  

• 	/delete-node/ aipstz@207c000;
  

• 	spba-bus@2000000 {
  

• 		/delete-property/ ranges;
  

• 		/delete-node/ spba@203c000;
  

• 	};
  

• };
  

• aips-bus@2100000 {
  

• 	/delete-property/ ranges;
  

• 	/delete-node/ aipstz@217c000;
  

• 	/delete-node/ mlb@218c000;
  

• 	/delete-node/ romcp@21ac000;
  

• 	/delete-node/ tzasc@21d0000;
  

• 	/delete-node/ tzasc@21d4000;
  

• 	/delete-node/ vdoa@21e4000;
  

• };
  

• };

+};

+&anatop {

• /delete-node/ regulator-1p1;
• /delete-node/ regulator-2p5;
• /delete-node/ regulator-3p0;
• /delete-node/ regulator-vddcore;
• /delete-node/ regulator-vddpu;
• /delete-node/ regulator-vddsoc;

+};

+&sata {

• /delete-property/ clocks;
• /delete-property/ clock-names;
• /delete-property/ interrupts;
• /delete-property/ interrupts;
• /delete-property/ fsl,transmit-level-mV;
• /delete-property/ fsl,transmit-boost-mdB;
• /delete-property/ fsl,transmit-atten-16ths;
• /delete-property/ fsl,receive-eq-mdB;

+};

+&pcie {

• /delete-property/ reg-names;
• /delete-property/ device_type;
• /delete-property/ bus-range;
• /delete-property/ ranges;
• /delete-property/ num-lanes;
• /delete-property/ interrupts;
• /delete-property/ interrupt-names;
• /delete-property/ #interrupt-cells;
• /delete-property/ interrupt-map-mask;
• /delete-property/ interrupt-map;
• /delete-property/ clocks;
• /delete-property/ clock-names;

+};

+&uart1 {

• /delete-property/ interrupts;
• /delete-property/ clocks;
• /delete-property/ clock-names;
• /delete-property/ dmas;
• /delete-property/ dma-names;

+};

+&uart2 {

• /delete-property/ interrupts;
• /delete-property/ clocks;
• /delete-property/ clock-names;
• /delete-property/ dmas;
• /delete-property/ dma-names;

+};

+/delete-node/ &L2; +/delete-node/ &asrc; +/delete-node/ &audmux; +/delete-node/ &can1; +/delete-node/ &can2; +/delete-node/ &crypto; +/delete-node/ &dcic1; +/delete-node/ &dcic2; +/delete-node/ &dma_apbh; +/delete-node/ &ecspi1; +/delete-node/ &ecspi2; +/delete-node/ &ecspi3; +/delete-node/ &ecspi4; +/delete-node/ &ecspi5; +/delete-node/ &epit1; +/delete-node/ &epit2; +/delete-node/ &esai; +/delete-node/ &gpt; +/delete-node/ &gpio4; +/delete-node/ &gpio5; +/delete-node/ &gpio6; +/delete-node/ &gpu_3d; +/delete-node/ &gpu_2d; +/delete-node/ &gpu_vg; +/delete-node/ &gpmi; +/delete-node/ &ipu2; +/delete-node/ &kpp; +/delete-node/ &ldb; +/delete-node/ &mipi_csi; +/delete-node/ &mmdc0; +/delete-node/ &mmdc1; +/delete-node/ &ocotp; +/delete-node/ &ocram; +/delete-node/ &pinctrl_gpio_fan; +/delete-node/ &pinctrl_ir; +/delete-node/ &pinctrl_gpio_leds; +/delete-node/ &pinctrl_sgtl5000; +/delete-node/ &pinctrl_spdif; +/delete-node/ &pmu; +/delete-node/ &pwm1; +/delete-node/ &pwm2; +/delete-node/ &pwm3; +/delete-node/ &pwm4; +/delete-node/ &sdma; +/delete-node/ &reg_2p5v; +/delete-node/ &sgtl5000; +/delete-node/ &snvs; +/delete-node/ &spdif; +/delete-node/ &src; +/delete-node/ &ssi1; +/delete-node/ &ssi2; +/delete-node/ &ssi3; +/delete-node/ &tempmon; +/delete-node/ &uart3; +/delete-node/ &uart4; +/delete-node/ &uart5; +/delete-node/ &usbh2; +/delete-node/ &usbh3; +/delete-node/ &usdhc1; +/delete-node/ &vpu; +/delete-node/ &wdog2; +/delete-node/ &weim;

+&gpr {

• /delete-node/ ipu1_csi0_mux;
• /delete-node/ ipu2_csi1_mux;

+};

+&gpc {

• /delete-node/ pgc;

+};

+&hdmi {

• /delete-node/ port@2;
• /delete-node/ port@3;

+};

+&mipi_dsi {

• ports {

• /delete-node/ port@2;
  

• /delete-node/ port@3;
  

• };

+};

+&ipu1 {

• u-boot,dm-pre-reloc;
• /delete-property/ interrupts;
• /delete-property/ clocks;
• /delete-property/ clock-names;
• /delete-property/ resets;
• /delete-node/ port@0;
• /delete-node/ port@1;
• port@2 {

• /delete-node/ endpoint@3;
  

• /delete-node/ endpoint@4;
  

• };
• port@3 {

• /delete-node/ endpoint@3;
  

• /delete-node/ endpoint@4;
  

• };

+};

Oh, most of the deleted properties and nodes are not defined in the board dts, but in the soc dtsi instead. So for me it would make more sense to also split the "delete dtsi" in a board and soc part, if this really is the way to go.

...

This gets an important conversation started. Perhaps we should expand OF_SPL_REMOVE_PROPS for full U-Boot, with some gating symbol for the platforms that do want to pass through the full DT to the OS?

I also already looked at OF_SPL_REMOVE_PROPS, would make much sense to have this for full u-boot. To duplicate each device tree with an almost identical "delete dtsi" looks like a huge maintenance burden for me.

Maybe the build system can at least automatically remove disabled nodes and nodes without compatible in enabled DM drivers. This would not help for unneeded properties in enabled nodes, but probably automatically give the biggest part of size reduction.

In an ideal world the firmware and not the operating system would supply the device tree for booting the operating system. Currently for many boards the U-Boot supplied device tree is enough to boot Linux. Deleting nodes not used by U-Boot would not be helpful in this context.

Best regards

Heinrich