Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752699AbcD1XbY (ORCPT ); Thu, 28 Apr 2016 19:31:24 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:32782 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752346AbcD1XbW (ORCPT ); Thu, 28 Apr 2016 19:31:22 -0400 Message-ID: <57229D47.6070704@gmail.com> Date: Thu, 28 Apr 2016 16:31:19 -0700 From: Frank Rowand Reply-To: frowand.list@gmail.com User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Rob Herring , Gaurav Minocha CC: Grant Likely , "devicetree@vger.kernel.org" , Linux Kernel list , Geert Uytterhoeven , Pavel Machek Subject: Re: [PATCH] scripts/dtc: dt_to_config - report kernel config options for a devicetree References: <572284AB.102@gmail.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7950 Lines: 204 On 4/28/2016 3:32 PM, Rob Herring wrote: > On Thu, Apr 28, 2016 at 4:46 PM, Frank Rowand wrote: >> From: Frank Rowand >> >> Determining which kernel config options need to be enabled for a >> given devicetree can be a painful process. Create a new tool to >> find the drivers that may match a devicetree node compatible, >> find the kernel config options that enable the driver, and >> optionally report whether the kernel config option is enabled. > > I would find this more useful to output a config fragment with all the > options enabled. The hard part there is enabling the options a given > option is dependent on which I don't think kbuild takes care of. > >> Signed-off-by: Gaurav Minocha >> Signed-off-by: Frank Rowand >> >> --- >> scripts/dtc/dt_to_config | 1061 +++++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 1061 insertions(+) >> >> Index: b/scripts/dtc/dt_to_config >> =================================================================== >> --- /dev/null >> +++ b/scripts/dtc/dt_to_config >> @@ -0,0 +1,1061 @@ >> +#!/usr/bin/perl > > I don't do perl... > >> + >> +# Copyright 2016 by Frank Rowand >> +# Š Copyright 2016 by Gaurav Minocha > ^ > Is this supposed to be a copyright symbol? Yes. Gaurav, can we drop this symbol? >> +# >> +# This file is subject to the terms and conditions of the GNU General Public >> +# License v2. > > [...] > >> +# ----- magic compatibles, do not have a driver >> +# >> +# Will not search for drivers for these compatibles. >> + >> +%compat_white_list = ( >> + 'fixed-partitions' => '1', > > Enabling CONFIG_MTD would be useful. Thanks! I'll dig deeper, but it likes like maybe CONFIG_MTD_OF_PARTS also. >> + 'none' => '1', > > Is this an actual string used somewhere? Yes. Looking at the output from running this against all .dts files has led to some interesting information. An example of compatible = "none" is node mct@10050000 from arch/arm/boot/dts/exynos4210-universal_c210.dts > >> + 'pci' => '1', > > ditto? arch/x86/platform/ce4100/falconfalls.dts, node pci@3fc >> + 'simple-bus' => '1', >> +); >> + >> +# magic compatibles, have a driver >> +# >> +# Will not search for drivers for these compatibles. >> +# Will instead use the drivers and config options listed here. >> +# >> +# If you add an entry to this hash, add the corresponding entry >> +# to %driver_config_hard_code_list. >> +# >> +# These compatibles have a very large number of false positives. > > What does this mean? That means that a _lot_ of garbage, bogus matches are reported, creating a lot of noise in the report. >> +# >> +# 'hardcoded_no_driver' is a magic value. Other code knows this >> +# magic value. Do not use 'no_driver' here! >> +# >> +# TODO: Revisit each 'hardcoded_no_driver' to see how the compatible >> +# is used. Are there drivers that can be provided? >> + >> +%driver_hard_code_list = ( >> + 'cache' => ['hardcoded_no_driver'], >> + 'eeprom' => ['hardcoded_no_driver'], >> + 'gpio' => ['hardcoded_no_driver'], >> + 'gpios' => ['drivers/leds/leds-tca6507.c'], >> + 'gpio-keys' => ['drivers/input/keyboard/gpio_keys.c'], >> + 'i2c-gpio' => ['drivers/i2c/busses/i2c-gpio.c'], >> + 'isa' => ['arch/mips/mti-malta/malta-dt.c', >> + 'arch/x86/kernel/devicetree.c'], >> + 'led' => ['hardcoded_no_driver'], >> + 'm25p32' => ['hardcoded_no_driver'], >> + 'm25p64' => ['hardcoded_no_driver'], >> + 'm25p80' => ['hardcoded_no_driver'], >> + 'mtd_ram' => ['drivers/mtd/maps/physmap_of.c'], >> + 'pwm-backlight' => ['drivers/video/backlight/pwm_bl.c'], >> + 'spidev' => ['hardcoded_no_driver'], >> + 'syscon' => ['drivers/mfd/syscon.c'], >> + 'tlv320aic23' => ['hardcoded_no_driver'], >> + 'wm8731' => ['hardcoded_no_driver'], >> +); >> + >> +%driver_config_hard_code_list = ( >> + >> + # this one needed even if %driver_hard_code_list is empty >> + 'no_driver' => ['no_config'], >> + 'hardcoded_no_driver' => ['no_config'], >> + >> + 'drivers/leds/leds-tca6507.c' => ['CONFIG_LEDS_TCA6507'], >> + 'drivers/input/keyboard/gpio_keys.c' => ['CONFIG_KEYBOARD_GPIO'], >> + 'drivers/i2c/busses/i2c-gpio.c' => ['CONFIG_I2C_GPIO'], >> + 'arch/mips/mti-malta/malta-dt.c' => ['obj-y'], >> + 'arch/x86/kernel/devicetree.c' => ['CONFIG_OF'], >> + 'drivers/mtd/maps/physmap_of.c' => ['CONFIG_MTD_PHYSMAP_OF'], >> + 'drivers/video/backlight/pwm_bl.c' => ['CONFIG_BACKLIGHT_PWM'], >> + 'drivers/mfd/syscon.c' => ['CONFIG_MFD_SYSCON'], > > I don't understand why some of these are not searchable by compatible strings. I will have to get back to you later on this question. >> + >> + # drivers/usb/host/ehci-ppc-of.c >> + # drivers/usb/host/ehci-xilinx-of.c >> + # are included from: >> + # drivers/usb/host/ehci-hcd.c >> + # thus the search of Makefile for the included .c files is incorrect >> + # ehci-hcd.c wraps the includes with ifdef CONFIG_USB_EHCI_HCD_..._OF >> + # >> + # similar model for ohci-hcd.c (but no ohci-xilinx-of.c) >> + # >> + # similarly, uhci-hcd.c includes uhci-platform.c >> + >> + 'drivers/usb/host/ehci-ppc-of.c' => ['CONFIG_USB_EHCI_HCD', >> + 'CONFIG_USB_EHCI_HCD_PPC_OF'], >> + 'drivers/usb/host/ohci-ppc-of.c' => ['CONFIG_USB_OHCI_HCD', >> + 'CONFIG_USB_OHCI_HCD_PPC_OF'], >> + >> + 'drivers/usb/host/ehci-xilinx-of.c' => ['CONFIG_USB_EHCI_HCD', >> + 'CONFIG_USB_EHCI_HCD_XILINX'], >> + >> + 'drivers/usb/host/uhci-platform.c' => ['CONFIG_USB_UHCI_HCD', >> + 'CONFIG_USB_UHCI_PLATFORM'], >> + >> + # scan_makefile will find only one of these config options: >> + # ifneq ($(CONFIG_SOC_IMX6)$(CONFIG_SOC_LS1021A),) >> + 'arch/arm/mach-imx/platsmp.c' => ['CONFIG_SOC_IMX6 && CONFIG_SMP', >> + 'CONFIG_SOC_LS1021A && CONFIG_SMP'], > > These will never get updated when the files or config options change. > Conversely, how do I know if I need to add something here? Is this > list complete or based on testing some set of dts files. IMO, this > list has to go to merge this. That is a concern that I have also. I added a warning flag in the flags field to indicate when one of these hard-coded values was used. The flag does not solve the issue, but does make it more visible. The list is a result of running against every dts file in the kernel tree and looking at the reports. >> +); >> + >> + >> +# 'virt/kvm/arm/.*' are controlled by makefiles in other directories, >> +# using relative paths, such as 'KVM := ../../../virt/kvm'. Do not >> +# add complexity to find_kconfig() to deal with this. There is a long >> +# term intent to change the kvm related makefiles to the normal kernel >> +# style. After that is done, this entry can be removed from the >> +# driver_black_list. >> + >> +@driver_black_list = ( >> + 'virt/kvm/arm/.*', >> +); > > A small number of exceptions like this I could stomach. > > The rest is just write-only language nonsense... > > Rob >