From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Date: Thu, 5 Mar 2020 14:17:28 +0200 Subject: [PATCH v1] x86: acpi: Refactor XSDT handling in acpi_add_table() In-Reply-To: References: <20200227140051.75072-1-andriy.shevchenko@linux.intel.com> Message-ID: <20200305121728.GH1224808@smile.fi.intel.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Tue, Mar 03, 2020 at 07:47:56PM -0700, Simon Glass wrote: > On Tue, 3 Mar 2020 at 02:23, Andy Shevchenko wrote: > > On Tue, Mar 3, 2020 at 1:36 AM Simon Glass wrote: > > > On Mon, 2 Mar 2020 at 13:47, Andy Shevchenko wrote: > > > > On Mon, Mar 2, 2020 at 9:47 PM Simon Glass wrote: > > > > > On Fri, 28 Feb 2020 at 01:47, Andy Shevchenko wrote: > > > > > > On Fri, Feb 28, 2020 at 1:41 AM Simon Glass wrote: > > > > > > > On Thu, 27 Feb 2020 at 06:00, Andy Shevchenko > > > > > > > wrote: > > > > > > > > > > > > > Could you take a look at the ACPI series? > > > > > > > > > > > > > > It was sent out about a month ago and has a refactor to this function. > > > > > > > > > > > > > > u-boot-dm/coral-working > > > > > > > > > > > > There are tons of changes. Care to point what changes are more > > > > > > important (generic to all x86)? > > > > > > > > > > I'm not quite sure about that...but x86 patches have an x86: tag, so > > > > > perhaps that helps? > > > > > > > > Okay, some like 50 of them or even more? I really don't want to spend > > > > time on the board related patches like "x86: apl:". > > > > > > Well that's why I add the tags, so you can see what they relate to. > > > This is probably a good one to review: > > > > > > dm: core: Add basic ACPI support > > > > Okay, I will try to find a time to look at it first. I started looking at them from the above mentioned patch. 1/ Can we do include/acpi/ folder for ACPI related headers? 2/ How this is supposed to be compiled? + table_compute_checksum((xsdt, xsdt->header.length); ...means this series should go thru bisectability tests (something like aiaiai https://lwn.net/Articles/488992/ script provides) 3/ This one looks not 64-bit compatible. + printf("RSDP %08lx %06x (v%02d %.6s)\n", (ulong)map_to_sysmem(rsdp), + rsdp->length, rsdp->revision, rsdp->oem_id); ...means that types for printing and all explicit casting should be revisited. Till this one "acpi: Add some tables required by the generation code" looks okay (in terms of approach). This one "acpi: Add generation code for devices" requires quite a good review. So, I would recommend to split the series (and this patch in particular) to smaller chunks. So does this "acpi: Add functions to generate ACPI code". They are unreviewable. Perhaps first pile some generalization that ARM people may start their work... > > > > > > P.S. Briefly looking at the last ~30 patches I can say that the idea > > > > > > looks good, implementation needs more work. For example, there is > > > > > > 'linux,name' property. Shouldn't be referred at all. Linux names and > > > > > > other type of enumerations is utterly opaque to the outside world. > > > > > > > > > > How do we add the required linux,name ACPI property into the ACPI > > > > > tables for a device? > > > > > > > > There must not be Linux device names or anything Linux related (like > > > > hardcoded GPIO numbers) in the ACPI table. > > > > > > Apparently the Intel GPIO driver requires that name. See for example here: > > > > > > https://elixir.bootlin.com/linux/latest/source/drivers/pinctrl/intel/pinctrl-broxton.c#L999 > > > > > > static const struct acpi_device_id bxt_pinctrl_acpi_match[] = { > > > { "INT3452", (kernel_ulong_t)apl_pinctrl_soc_data }, > > > { "INT34D1", (kernel_ulong_t)bxt_pinctrl_soc_data }, > > > { } > > > }; > > > > > > So we have to put INT3452 in the ACPI table. > > > > Wait, this is not a *name*, this is ACPI _HID. ACPI _HID, of course, > > should be somewhere in board code. > > > > I was thinking myself about some U-Boot framework that actually takes > > ACPI _HID from the driver. So, when you define in U-Boot device tree a > > compatible string (for U-Boot use), in the driver it will have in the > > class structure the callback / field / stubstructure to use when ACPI > > generate tables is enabled. It will drop duplication of compatible > > with ACPI _HID in each DTS. > > Why are you so opposed to using device tree for this? The GPIO and > pinctrl drivers are intended to be generic....what a pain to add all > this stuff into the tables in the driver! So, this is a trade off between C code and DTS. I'm okay to use DTS for the stuff that belongs to it. But then, if we enable DTS for ACPI tables generation, we have to provide a mean to do it without driver involvement. How to generate the table for the device U-Boot has no driver for? > When other platforms use APL we can move some .dts nodes over into a > intel-apl.dtsi file (or similar) to deal with any duplication. Of > course we don't want duplication. > > Re the thread that Wolfgang references, I'm going to have a close look > at that and hopefully simplify things. We still need quite a bit more > patches to be reviewed before it is worth sending again, I think. Yes, please. My main point here is to avoid data duplication because it's simpler to pollute DTS with it. > > But to the current topic, you put *instance* (not even _HID) to the DT > > with property called "linux,name". It's inappropriate. NAK for that > > for sure. > > OK, so are you saying the property name (linux-name) should change? We > have acpi,name elsewhere but I don't think that is the _HID. > > Or are you saying that the "INT3452:" should be factored out and it > should know the 00/01/0203 by its position in the device tree? It shouldn't be anywhere in the U-Boot, it's complete OS business. What you have in U-Boot is ACPI _HID (_UID, etc.), and device path (e.g. \\_SB_.GPO0), no-one should rely on OS (Linux, Windows, etc) internals. We have already an issue with GPIO pin numbers on Chromebook with Intel Cherryview SoC. This + linux-name = "INT3452:00"; is wrong in both sides -- left, as a property name, and right, as an *instance* in some OS we must not rely on ever. The question is why do you need it? > > > > > > On top of that, I think we rather need to have a conversion layer than > > > > > > putting some names inside DT, like \_SB_.GPO0 should be generated > > > > > > automatically from DT node. That said, I don't like DT being polluted > > > > > > with non-DT stuff. > > > > > > > > > > Well DT is the configuration mechanism for U-Boot. > > > > > > > > > > \_SB_.GPO0 is a special case since it actually refers to pinctrl (ACPI > > > > > seems to make no distinction between pinctrl and GPIO) and this node > > > > > is inside p2sb: > > > > > > > > > > pci { > > > > > p2sb at d,0 { > > > > > n { > > > > > gpio-n { > > > > > > > > > > So the automatically generated path would have p2sb in it. The same > > > > > work-around is in coreboot. > > > > > > > > It's not a coreboot, we may do better, right? > > > > So, generation can strip p2sb (special case) from all p2sb devices. > > > > However, I'm not sure I understand how p2sb is involved in GPIO > > > > enumeration, > > > > > > Well the only other way to create a path is to work up to the root and > > > build it node by node. I wonder if we could make p2sb be transparent? > > > I tried that but hit a problem. > > > > > > Coreboot has these really awful (IMO) functions that are repeated for every SoC: > > > > > > https://github.com/coreboot/coreboot/blob/master/src/soc/amd/stoneyridge/chip.c > > > > > > so I want to avoid that. I'm not sure I understood how the mentioned source file related to P2SB case. In that file PCIe functions and USB ports are described. -- With Best Regards, Andy Shevchenko