From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bin Meng Date: Wed, 27 Nov 2019 14:04:27 +0800 Subject: [U-Boot] [PATCH v3] arm: add acpi support for the arm In-Reply-To: References: <95759692-4ccf-200b-1e94-592c9721a9ff@gmx.de> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: u-boot@lists.denx.de Hi Simon, On Wed, Nov 27, 2019 at 11:42 AM Simon Glass wrote: > > Hi Heinrich, > > On Mon, 25 Nov 2019 at 18:12, Heinrich Schuchardt wrote: > > > > On 11/26/19 12:40 AM, Simon Glass wrote: > > > Hi, > > > > > > On Mon, 25 Nov 2019 at 15:57, Heinrich Schuchardt wrote: > > >> > > >> On 11/25/19 3:42 AM, Steven Hao wrote:> 获取 Outlook for iOS > > >> > > >>> ------------------------------------------------------------------------ > > >>> *发件人:* Bin Meng > > >>> *发送时间:* Monday, November 25, 2019 10:13:40 AM > > >>> *收件人:* Steven Hao > > >>> *抄送:* xypron.glpk at gmx.de ; liuhao at phytium.com.cn > > >>> ; agraf at csgraf.de ; > > >>> jagan at amarulasolutions.com ; > > >>> marek.vasut at gmail.com ; sr at denx.de ; > > >>> patrice.chotard at st.com ; afd at ti.com > > >>> ; horatiu.vultur at microchip.com > > >>> ; narmstrong at baylibre.com > > >>> ; ryder.lee at mediatek.com > > >>> ; igor.opaniuk at gmail.com > > >>> ; patrick.delaunay at st.com > > >>> ; eugen.hristev at microchip.com > > >>> ; sjg at chromium.org ; > > >>> judge.packham at gmail.com ; > > >>> yamada.masahiro at socionext.com ; > > >>> swarren at nvidia.com ; michal.simek at xilinx.com > > >>> ; u-boot at lists.denx.de ; > > >>> Andy Shevchenko > > >>> *主题:* Re: [PATCH v3] arm: add acpi support for the arm > > >>> Hi Steven, > > >>> > > >>> On Mon, Nov 25, 2019 at 10:09 AM Steven Hao > > >>> wrote: > > >>>> > > >>>> Dear Bin： > > >>>> > > >>>> Firstly： > > >>>> I know that acpi about x86 is existing. And it is usefull for x86 > > >> platfporm. If it is used to arm platform，some modification may have to > > >> do. For example，facs table is useless for arm. > > >>>> > > >>>> In adition，The acpi table is writed statically and then modified > > >> dynamically in my patch. It is a new method. > > >>>> > > >>>> I want to consult that whether my method is helpful or not. > > >>>> > > >>>> Secondly： > > >>>> If i want to reuse the x86-acpi. I will overwrite the > > >> write_acpi_tables function. But the definition about acpi strcuture is > > >> placed in arch/x86/include/asm directory. It can not be used to arm > > >> plateform. If the acpi library need to surport for all platform，i think > > >> it should move to /include directory. > > >>>> > > >>> > > >>> Yes, we all are aware that modifications are needed to the existing > > >>> x86 ACPI support to support ARM. We don't want to create 2 ACP > > >>> implementation in U-Boot. > > >>> > > >>> Regards, > > >>> Bin> Dear Bin： > > >>> > > >>> I have a suggetion that the acpi specification definition such as all > > >>> acpi table structure definition should be place in /include directory. > > >>> and write_acpi_tables function can be placed in platform directory. > > >>> Creating acpi table mothod can be diffrent between x86 and arm. > > >>> > > >>> Thank you > > >>> Steven Hao > > >>> > > >> > > >> Currently we are using CPU specific C files generating ACPI tables, e.g. > > >> arch/x86/cpu/tangier/acpi.c. > > >> > > >> I would prefer if we would generate the ACPI tables and definition > > >> blocks completely from text files instead of using C code. This would > > >> avoid any architecture specific code. > > > > > > I am finding with Apollo Lake that this isn't possible - we need to > > > insert run-time information into the tables set up with .asl files. > > > > For device trees we generate the binary form with a compiler. Then we > > patch the device tree with runtime information in image_setup_libfdt(). > > > > Couldn't we go a similar way for ACPI? > > Yes that's my goal, except that some tables are generated wholesale > from code (equivalent to entire nodes in DT). > > I had a bit of a look at how this is done in coreboot. It is pretty > hard to follow as there are weak functions and the code jumps back and > forth between generic code and SoC-specific code. But every device has > ACPI operation and I think that makes sense. > > My current idea is to add a new optional acpi_ops struct pointer into > each struct driver, to handle the ACPI table generation and other > things needed by ACPI. Then devices that want to do ACPI things can do > so. Then we need a new drivers/core/acpi.c file to handle things. > Yes, this approach makes sense to me, for dynamic ACPI table generation. Regards, Bin