I have to agree that reducing it to 2 HALs (one ACPI with multiprocessor and such, that maybe is also used for single-cpu systems with ACPI), and a legacy one for systems unable to handle ACPI+MP, sounds like a great idea.
On 12 December 2017 at 18:13, Javier Agustìn Fernàndez Arroyo < elh...@gmail.com> wrote: > Win8 does not support old hardware as ReactOS do! > > El 12 dic. 2017 17:52, "Alex Ionescu" <ion...@videotron.ca> escribió: > >> I would move to the Win8+ HAL Model -- a single HAL for APIC, ACPI with >> runtime support for UEFI (if present) and MP (if present). >> >> If people still want to run on a PIC VM (why???) or old computer, then we >> can also maintain the HAL PIC x86 for UP. >> >> Hence there would only be 2 HALs. >> >> Best regards, >> Alex Ionescu >> >> On Mon, Dec 11, 2017 at 1:07 AM, Colin Finck <co...@reactos.org> wrote: >> >>> Am 11.12.2017 um 01:18 schrieb Hermès BÉLUSCA-MAÏTO:> If you basically >>> put all the HALs into one, then you obtain bloated stuff (which remains >>> in memory for the whole life of the OS). Example: standard HAL is 1MB >>> vs. ACPI HAL which is few kBHave you actually checked what makes up this >>> difference? >>> Hint: hal/halx86/legacy/bus/pci_vendors.ids >>> >>> >>> > Note that if Windows nowadays has only one hal, it's because they now >>> support basically only one "architecture"/platform, namely, ACPI >>> multiprocessor (to put it simple). It has its pros, but also a lot of cons. >>> >>> That doesn't mean we need to do the same. We can have one HAL for all >>> (Pentium and newer) x86 platforms. The overhead of additional checks at >>> boot-up is negligible. That should be a solution for 99% of the people >>> out there. The rest may still go and trim down our HAL to their needs. >>> >>> But let's not pretend we can maintain multiple x86 HALs for all x86 >>> computers out there. Do you really want to test X HALs with Y different >>> systems? Ensure that a legacy HAL runs on a modern ACPI system? What >>> would be the point? >>> >>> >>> > Besides this, I've a question about your observation that in the APIC >>> hal (not ACPI) there's different implementation of >>> HalpCalibrateStallExecution and HalpInitializePICs / >>> HalpInitializeLegacyPIC . Isn't it precisely because these stuff are >>> completely different from the standard PICs used in platforms for which the >>> standard HAL (and possibly the ACPI HAL) are used? >>> >>> Absolutely not! You need to reprogram the standard PICs also on an APIC >>> system, and this is precisely what both functions do. Put them into a >>> diff tool to see for yourself. >>> >>> The same goes for timers. Even with the introduction of ACPI Timers, >>> Local APIC Timers, and Time-Stamp Counters, you still need a traditional >>> one (like RTC or PIT) for calibration at system startup. Simply because >>> the newer ones don't run at a known fixed frequency. >>> The Legacy HAL successfully employs an algorithm based on the RTC while >>> the APIC HAL unsuccessfully tries to use the PIT. >>> >>> >>> > Actually we should, because the detection might not work (of course in >>> our simple case "ACPI UP/MP" vs. "Standard", it's simple, but think about >>> other platforms where there can be subtle differences) >>> >>> Tell me about a single one we cannot detect and which is worth to >>> support. I don't recall that we ever recommended our testers to choose a >>> different HAL at setup. >>> >>> >>> > And normally it's not the setup that decides about the HAL, but the >>> bootloader. >>> >>> That defies your previous point about the setup initializing the >>> registry depending on the HAL. >>> If we can let the user select a Legacy HAL in the boot loader after >>> installing with an ACPI HAL, it is also technically possible to have one >>> HAL that encompasses both. >>> >>> >>> - Colin >>> >>> _______________________________________________ >>> Ros-dev mailing list >>> Ros-dev@reactos.org >>> http://www.reactos.org/mailman/listinfo/ros-dev >>> >> >> >> _______________________________________________ >> Ros-dev mailing list >> Ros-dev@reactos.org >> http://www.reactos.org/mailman/listinfo/ros-dev >> > > _______________________________________________ > Ros-dev mailing list > Ros-dev@reactos.org > http://www.reactos.org/mailman/listinfo/ros-dev >
_______________________________________________ Ros-dev mailing list Ros-dev@reactos.org http://www.reactos.org/mailman/listinfo/ros-dev
