From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f42.google.com (mail-wr1-f42.google.com [209.85.221.42]) by mx.groups.io with SMTP id smtpd.web11.11161.1636029826444130466 for ; Thu, 04 Nov 2021 05:43:46 -0700 Authentication-Results: mx.groups.io; dkim=pass header.i=@nuviainc-com.20210112.gappssmtp.com header.s=20210112 header.b=Y8h5U5/W; spf=pass (domain: nuviainc.com, ip: 209.85.221.42, mailfrom: leif@nuviainc.com) Received: by mail-wr1-f42.google.com with SMTP id u1so8376315wru.13 for ; Thu, 04 Nov 2021 05:43:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nuviainc-com.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=C1of7BUAKyJHEfCLVDAfKkFeHkMjvpSZmp1HvYlCrf4=; b=Y8h5U5/WoKUAS9VL81+l0G2PloeB991gY5NNS4vg945qCOZE2/3W3EOgNBDGXKXn2F vVI0SGCa5hKPDwJgM1Jej2FUMA/TJ/yJ0lmR3A3rhKWddxa/h0AeBPtbP4N7w/xgrRB9 Hnpd8Cy4sdrrZ+u0lwyRU3MpBXjTsrugPCSoVcJHAElDw4nGDAdYDA1VI2BW40sdShPm rK2Yon6AFc2/1SufhW+IKf0flEGT25ZYFaX7tZESaXsA8CNZbIdFMhrt53noCLrL3Kug OBiale/pJxtq2jw2lK1qWXvg3dwJ3IJA0JhIxNwsaXkZo66u3ncEIrKyvOtfiaRCK+ch uV8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=C1of7BUAKyJHEfCLVDAfKkFeHkMjvpSZmp1HvYlCrf4=; b=kgFeyVCsOVbTLOrnPb+7sL5T37Jg+Wj6usAh8slb78RiDif75tMjTZNlJZN+Cu2nHC P7U6QEiy68aj1I93B19THyj4N5cfu28e8JeUuHjoT7f9DTfnUI2aTWXr7d9sYJ4prYMS iXMjxlqblyBgUuvD9PX/H6RdhIyCmHzPEZ2lh7cAkWsM9akF2sFD1RhaTJQAJ585N+Mt OQKzLY/wttjo2MfgzzPIGxWNV0oeAJ0dlmzW0U0vxT5LV9U+BWanN5wN0sfdn60wY2K+ 1Q4SLG3zR5m1Od3cujZXfjan2qjwzwFd/NuM9IBuqztCLpqPyVxUqgGB44/E8xWxsWmK IoOA== X-Gm-Message-State: AOAM530wp2kmsqk+DQIlGmiBa9OTKgXXBSn+deFWMObOn1jaU9GQE3oD tgznxO7WCIrjxsb7Cx4w6Vwkxg== X-Google-Smtp-Source: ABdhPJwUUhdPt0Q75OVkYvP6EhBsKlhpTNcU8LmUuQl5RJrZ24CznptpPveefjKXQIJn/MmjZNKDpg== X-Received: by 2002:adf:df0b:: with SMTP id y11mr40071132wrl.181.1636029824729; Thu, 04 Nov 2021 05:43:44 -0700 (PDT) Return-Path: Received: from leviathan (cpc92314-cmbg19-2-0-cust559.5-4.cable.virginm.net. [82.11.186.48]) by smtp.gmail.com with ESMTPSA id h27sm9864844wmc.43.2021.11.04.05.43.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Nov 2021 05:43:44 -0700 (PDT) Date: Thu, 4 Nov 2021 12:43:42 +0000 From: "Leif Lindholm" To: "brbarkel@microsoft.com" Cc: devel@edk2.groups.io, Ard Biesheuvel , Sean Brogan Subject: Re: [PATCH v2 11/16] ArmPkg: Add Basic MMU Lib for Arm silicon Message-ID: <20211104124342.y3wkleuohac67p7a@leviathan> References: <20211102201748.1963-1-brbarkel@microsoft.com> <20211102201748.1963-12-brbarkel@microsoft.com> MIME-Version: 1.0 In-Reply-To: <20211102201748.1963-12-brbarkel@microsoft.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Nov 02, 2021 at 13:17:43 -0700, brbarkel@microsoft.com wrote: > From: Sean Brogan > > The previously Arm-specific "ArmMmuLib" has been generalized > as "MmuLib". The Arm implementation of this lib can still use > the existing library logic to back it. > > As such, this implementation is currently just a shim to the > old library, while enabling higher-level code to be more > common. This commit message still required me to go and cross refecence a few patches to (I think) understand what's going on. (not least because it relies on a patch to MdePkg which I wasn't cc:d on, so hadn't spotted.) Correct me if I've got this wrong, but here's my theory: - 8/16 adds a library class that currently basically amounts to an unabstracted version of ArmMmuLib, but in MdePkg, minus the Arm prefixes. - 9/16 switches MdeModulePkg to use the new MmuLib instead of ArmMmuLib. - 10/16 does the same for StandaloneMmPkg. - 11/16 adds an actual implementation of this library class under ArmPkg - backed by ArmMmuLib. If that's accurate... Starting with the commit message - could we reduce the use of passive voice a bit? Suggestion: --- After adding the abstract MmuLib to MdePkg, add an implementation backed by the existing ArmMmuLib to ArmPkg. --- While not required functionality-wise, it would also feel more logical to me to add the arch-specific implementation immediately after the abstract version rather than a few patches down the set (kees the reviewer in the same context). / Leif > REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3651 > > Cc: Leif Lindholm > Cc: Ard Biesheuvel > Cc: Sean Brogan > Signed-off-by: Bret Barkelew > --- > ArmPkg/Library/MmuLib/MmuLib.c | 120 ++++++++++++++++++++ > ArmPkg/ArmPkg.dsc | 1 + > ArmPkg/Library/MmuLib/BaseMmuLib.inf | 30 +++++ > 3 files changed, 151 insertions(+) > > diff --git a/ArmPkg/Library/MmuLib/MmuLib.c b/ArmPkg/Library/MmuLib/MmuLib.c > new file mode 100644 > index 000000000000..70840c26f489 > --- /dev/null > +++ b/ArmPkg/Library/MmuLib/MmuLib.c > @@ -0,0 +1,120 @@ > +/** @file > +This library instance implements a very limited MMU Lib instance > +for the ARM/AARCH64 architectures. This library shims a common library > +interface to the ArmPkg defined ArmMmuLib.ib. > + > +Copyright (c) Microsoft Corporation. > +SPDX-License-Identifier: BSD-2-Clause-Patent > + > +**/ > + > +#include > +#include > +#include > + > +/** > + Bitwise sets the memory attributes on a range of memory based on an attributes mask. > + > + @param BaseAddress The start of the range for which to set attributes. > + @param Length The length of the range. > + @param Attributes A bitmask of the attributes to set. See "Physical memory > + protection attributes" in UefiSpec.h > + > + @return EFI_SUCCESS > + @return Others > + > +**/ > +EFI_STATUS > +EFIAPI > +MmuSetAttributes ( > + IN EFI_PHYSICAL_ADDRESS BaseAddress, > + IN UINT64 Length, > + IN UINT64 Attributes > + ) > + { > + EFI_STATUS Status; > + > + Status = EFI_UNSUPPORTED; > + > + if (Attributes & EFI_MEMORY_XP) { > + Status = ArmSetMemoryRegionNoExec (BaseAddress, Length); > + if (EFI_ERROR(Status)) { > + DEBUG((DEBUG_ERROR, "%a - Failed to set NX. Status = %r\n", __FUNCTION__, Status)); > + } > + } > + > + ASSERT_EFI_ERROR(Status); > + return Status; > + } > + > + > +/** > + Bitwise clears the memory attributes on a range of memory based on an attributes mask. > + > + @param BaseAddress The start of the range for which to clear attributes. > + @param Length The length of the range. > + @param Attributes A bitmask of the attributes to clear. See "Physical memory > + protection attributes" in UefiSpec.h > + > + @return EFI_SUCCESS > + @return Others > + > +**/ > +EFI_STATUS > +EFIAPI > +MmuClearAttributes ( > + IN EFI_PHYSICAL_ADDRESS BaseAddress, > + IN UINT64 Length, > + IN UINT64 Attributes > + ) > + { > + EFI_STATUS Status; > + > + Status = EFI_UNSUPPORTED; > + > + if (Attributes & EFI_MEMORY_XP) { > + Status = ArmClearMemoryRegionNoExec (BaseAddress, Length); > + if (EFI_ERROR(Status)) { > + DEBUG((DEBUG_ERROR, "%a - Failed to clear NX. Status = %r\n", __FUNCTION__, Status)); > + } > + } > + > + if (Attributes & EFI_MEMORY_RO) { > + Status = ArmClearMemoryRegionReadOnly(BaseAddress, Length); > + if (EFI_ERROR(Status)) { > + DEBUG((DEBUG_ERROR, "%a - Failed to clear RO. Status = %r\n", __FUNCTION__, Status)); > + } > + } > + > + ASSERT_EFI_ERROR(Status); > + return Status; > + } > + > + > +/** > + Returns the memory attributes on a range of memory. > + > + @param BaseAddress The start of the range for which to set attributes. > + @param Attributes A return pointer for the attributes. > + > + @return EFI_SUCCESS > + @return EFI_INVALID_PARAMETER A return pointer is NULL. > + @return Others > + > +**/ > +EFI_STATUS > +EFIAPI > +MmuGetAttributes ( > + IN EFI_PHYSICAL_ADDRESS BaseAddress, > + OUT UINT64 *Attributes > + ) > + { > + EFI_STATUS Status; > + > + Status = EFI_UNSUPPORTED; > + > + DEBUG ((DEBUG_ERROR, "%a() API not implemented\n", __FUNCTION__)); > + > + ASSERT_EFI_ERROR(Status); > + return Status; > + } > diff --git a/ArmPkg/ArmPkg.dsc b/ArmPkg/ArmPkg.dsc > index 06ede068f99d..cbc67daa7696 100644 > --- a/ArmPkg/ArmPkg.dsc > +++ b/ArmPkg/ArmPkg.dsc > @@ -165,3 +165,4 @@ [Components.AARCH64] > > [Components.AARCH64, Components.ARM] > ArmPkg/Library/StandaloneMmMmuLib/ArmMmuStandaloneMmLib.inf > + ArmPkg/Library/MmuLib/BaseMmuLib.inf > diff --git a/ArmPkg/Library/MmuLib/BaseMmuLib.inf b/ArmPkg/Library/MmuLib/BaseMmuLib.inf > new file mode 100644 > index 000000000000..15095abee9c3 > --- /dev/null > +++ b/ArmPkg/Library/MmuLib/BaseMmuLib.inf > @@ -0,0 +1,30 @@ > +## @file > +# This library instance implements a very limited MMU Lib instance > +# for the ARM/AARCH64 architectures. This library shims a common library > +# interface to the ArmPkg defined ArmMmuLib. > +# > +# Copyright (c) Microsoft Corporation. > +# > +# SPDX-License-Identifier: BSD-2-Clause-Patent > +# > +## > + > +[Defines] > + INF_VERSION = 0x00010005 > + BASE_NAME = MmuLib > + FILE_GUID = 6f2ee9a4-79b3-4b77-9a47-e2bd4b917b75 > + MODULE_TYPE = BASE > + VERSION_STRING = 1.0 > + LIBRARY_CLASS = MmuLib > + > +[Sources] > + MmuLib.c > + > +[Packages] > + MdePkg/MdePkg.dec > + MdeModulePkg/MdeModulePkg.dec > + ArmPkg/ArmPkg.dec > + > +[LibraryClasses] > + DebugLib > + ArmMmuLib > -- > 2.31.1.windows.1 >