It seems like a hard thing that how to support arm apci. ________________________________ 发件人: Heinrich Schuchardt xypron.glpk@gmx.de 发送时间: 2019年11月26日 8:58 收件人: Simon Glass sjg@chromium.org 抄送: Steven Hao steven_hao5189@outlook.com; Bin Meng bmeng.cn@gmail.com; liuhao@phytium.com.cn liuhao@phytium.com.cn; agraf@csgraf.de agraf@csgraf.de; jagan@amarulasolutions.com jagan@amarulasolutions.com; marek.vasut@gmail.com marek.vasut@gmail.com; sr@denx.de sr@denx.de; patrice.chotard@st.com patrice.chotard@st.com; afd@ti.com afd@ti.com; horatiu.vultur@microchip.com horatiu.vultur@microchip.com; narmstrong@baylibre.com narmstrong@baylibre.com; ryder.lee@mediatek.com ryder.lee@mediatek.com; igor.opaniuk@gmail.com igor.opaniuk@gmail.com; patrick.delaunay@st.com patrick.delaunay@st.com; eugen.hristev@microchip.com eugen.hristev@microchip.com; judge.packham@gmail.com judge.packham@gmail.com; yamada.masahiro@socionext.com yamada.masahiro@socionext.com; swarren@nvidia.com swarren@nvidia.com; michal.simek@xilinx.com michal.simek@xilinx.com; u-boot@lists.denx.de u-boot@lists.denx.de; Andy Shevchenko andriy.shevchenko@linux.intel.com 主题: Re: [PATCH v3] arm: add acpi support for the arm
On 11/26/19 12:40 AM, Simon Glass wrote:
Hi,
On Mon, 25 Nov 2019 at 15:57, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 11/25/19 3:42 AM, Steven Hao wrote:> 获取 Outlook for iOS https://aka.ms/o0ukef
*发件人:* Bin Meng bmeng.cn@gmail.com *发送时间:* Monday, November 25, 2019 10:13:40 AM *收件人:* Steven Hao steven_hao5189@outlook.com *抄送:* xypron.glpk@gmx.de xypron.glpk@gmx.de; liuhao@phytium.com.cn liuhao@phytium.com.cn; agraf@csgraf.de agraf@csgraf.de; jagan@amarulasolutions.com jagan@amarulasolutions.com; marek.vasut@gmail.com marek.vasut@gmail.com; sr@denx.de sr@denx.de; patrice.chotard@st.com patrice.chotard@st.com; afd@ti.com afd@ti.com; horatiu.vultur@microchip.com horatiu.vultur@microchip.com; narmstrong@baylibre.com narmstrong@baylibre.com; ryder.lee@mediatek.com ryder.lee@mediatek.com; igor.opaniuk@gmail.com igor.opaniuk@gmail.com; patrick.delaunay@st.com patrick.delaunay@st.com; eugen.hristev@microchip.com eugen.hristev@microchip.com; sjg@chromium.org sjg@chromium.org; judge.packham@gmail.com judge.packham@gmail.com; yamada.masahiro@socionext.com yamada.masahiro@socionext.com; swarren@nvidia.com swarren@nvidia.com; michal.simek@xilinx.com michal.simek@xilinx.com; u-boot@lists.denx.de u-boot@lists.denx.de; Andy Shevchenko andriy.shevchenko@linux.intel.com *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 steven_hao5189@outlook.com 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?
Best regards
Heinrich
Such table generation is already in use in the Windows world. See: https://docs.microsoft.com/en-us/windows-hardware/drivers/bringup/generate-a...
That looks like a programmatic way to create ACPI tables. If so, I'm trying to bring something similar over from coreboot.
Regards, Simon