From: "Pete Batard" <pete@akeo.ie>
To: Andrei Warkentin <andrey.warkentin@gmail.com>, devel@edk2.groups.io
Cc: ard.biesheuvel@arm.com, leif@nuviainc.com, philmd@redhat.com
Subject: Re: [edk2-platforms][PATCH 1/1] RPi4: reserve/map memory above 4GB when present
Date: Tue, 2 Jun 2020 18:52:20 +0100 [thread overview]
Message-ID: <391575f7-f6c8-fd25-0c8b-539d1e86d262@akeo.ie> (raw)
In-Reply-To: <20200601091020.108704-1-andrey.warkentin@gmail.com>
A few minor notes inline:
On 2020.06.01 10:10, Andrei Warkentin wrote:
> This makes all 8GB usable on the Pi 4 8GB variant.
>
> Like RAM in the 3-4GB range, this is still gated by the
> option to limit RAM to 3GB.
>
> Tested on 4GB and 8GB boards, with and without 3GB limit.
>
> Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com>
> ---
> Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c | 32 +++++--
> Platform/RaspberryPi/Library/PlatformLib/PlatformLib.inf | 1 -
> Platform/RaspberryPi/Library/PlatformLib/RaspberryPiMem.c | 99 ++++++++++++--------
> Platform/RaspberryPi/RPi4/RPi4.dsc | 1 -
> Platform/RaspberryPi/RaspberryPi.dec | 1 -
> 5 files changed, 85 insertions(+), 49 deletions(-)
>
> diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
> index ad14eb3d..5f8e7109 100644
> --- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
> +++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
> @@ -339,7 +339,6 @@ ApplyVariables (
> UINT32 CpuClock = PcdGet32 (PcdCpuClock);
> UINT32 CustomCpuClock = PcdGet32 (PcdCustomCpuClock);
> UINT32 Rate = 0;
> - UINT64 SystemMemorySize;
>
> switch (CpuClock) {
> case CHIPSET_CPU_CLOCK_LOW:
> @@ -382,27 +381,42 @@ ApplyVariables (
>
> if (mModelFamily >= 4 && PcdGet32 (PcdRamMoreThan3GB) != 0 &&
> PcdGet32 (PcdRamLimitTo3GB) == 0) {
> + UINT64 SystemMemorySize;
> + UINT64 SystemMemorySizeBelow4GB;
Might be worth explaining that we want to handle < 4 GB memory in a
special way, and thus introduce this special variable, on account of
performing the 32-bit SoC register overlap.
> /*
> * Similar to how we compute the > 3 GB RAM segment's size in PlatformLib/
> * RaspberryPiMem.c, with some overlap protection for the Bcm2xxx register
> - * spaces. This computation should also work for models with more than 4 GB
> - * RAM, if there ever exist ones.
> + * spaces.
> */
> SystemMemorySize = (UINT64)mModelInstalledMB * SIZE_1MB;
> - ASSERT (SystemMemorySize > 3UL * SIZE_1GB);
> - SystemMemorySize = MIN(SystemMemorySize, BCM2836_SOC_REGISTERS);
> +
> + SystemMemorySizeBelow4GB = MIN(SystemMemorySize, 4UL * SIZE_1GB);
> + SystemMemorySizeBelow4GB = MIN(SystemMemorySizeBelow4GB, BCM2836_SOC_REGISTERS);
> if (BCM2711_SOC_REGISTERS > 0) {
> - SystemMemorySize = MIN(SystemMemorySize, BCM2711_SOC_REGISTERS);
> + SystemMemorySizeBelow4GB = MIN(SystemMemorySizeBelow4GB, BCM2711_SOC_REGISTERS);
> }
> + ASSERT (SystemMemorySizeBelow4GB - 3UL * SIZE_1GB > 0);
ASSERTs work better for me, and possibily others reading the code, when,
if you are comparing A to B, you're no using "A - B > 0" but "A > B".
In other words, I think (SystemMemorySizeBelow4GB > 3UL * SIZE_1GB)
would be clearer, which is also how the ASSERT was originally.
> Status = gDS->AddMemorySpace (EfiGcdMemoryTypeSystemMemory, 3UL * BASE_1GB,
> - SystemMemorySize - (3UL * SIZE_1GB),
> + SystemMemorySizeBelow4GB - (3UL * SIZE_1GB),
> EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | EFI_MEMORY_WB);
> ASSERT_EFI_ERROR (Status);
> Status = gDS->SetMemorySpaceAttributes (3UL * BASE_1GB,
> - SystemMemorySize - (3UL * SIZE_1GB),
> - EFI_MEMORY_WB);
> + SystemMemorySizeBelow4GB - (3UL * SIZE_1GB), EFI_MEMORY_WB);
> ASSERT_EFI_ERROR (Status);
> +
> + if (SystemMemorySize - 4UL * SIZE_1GB > 0) {
> + //
> + // Register any memory above 4GB.
> + //
> + Status = gDS->AddMemorySpace (EfiGcdMemoryTypeSystemMemory, 4UL * BASE_1GB,
> + SystemMemorySize - (4UL * SIZE_1GB),
> + EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT | EFI_MEMORY_WB);
> + ASSERT_EFI_ERROR (Status);
> + Status = gDS->SetMemorySpaceAttributes (4UL * BASE_1GB,
> + SystemMemorySize - (4UL * SIZE_1GB), EFI_MEMORY_WB);
> + ASSERT_EFI_ERROR (Status);
> + }
> }
>
> if (mModelFamily == 3 || mModelFamily == 2) {
> diff --git a/Platform/RaspberryPi/Library/PlatformLib/PlatformLib.inf b/Platform/RaspberryPi/Library/PlatformLib/PlatformLib.inf
> index f48016cc..54c3f303 100644
> --- a/Platform/RaspberryPi/Library/PlatformLib/PlatformLib.inf
> +++ b/Platform/RaspberryPi/Library/PlatformLib/PlatformLib.inf
> @@ -55,7 +55,6 @@
> gEmbeddedTokenSpaceGuid.PcdDmaDeviceOffset
> gArmTokenSpaceGuid.PcdSystemMemoryBase
> gArmTokenSpaceGuid.PcdSystemMemorySize
> - gRaspberryPiTokenSpaceGuid.PcdExtendedMemoryBase
> gRaspberryPiTokenSpaceGuid.PcdNvStorageEventLogSize
> gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageVariableSize
> gEfiMdeModulePkgTokenSpaceGuid.PcdFlashNvStorageFtwWorkingSize
> diff --git a/Platform/RaspberryPi/Library/PlatformLib/RaspberryPiMem.c b/Platform/RaspberryPi/Library/PlatformLib/RaspberryPiMem.c
> index aae189ec..61c50157 100644
> --- a/Platform/RaspberryPi/Library/PlatformLib/RaspberryPiMem.c
> +++ b/Platform/RaspberryPi/Library/PlatformLib/RaspberryPiMem.c
> @@ -58,18 +58,55 @@ ArmPlatformGetVirtualMemoryMap (
> {
> UINTN Index = 0;
> UINTN GpuIndex;
> - INT64 OrigMemorySize;
> - INT64 SystemMemorySize;
> + INT64 TotalMemorySize;
> + INT64 MemorySizeBelow3GB;
> + INT64 MemorySizeBelow4GB;
> ARM_MEMORY_REGION_DESCRIPTOR *VirtualMemoryTable;
>
> // Early output of the info we got from VideoCore can prove valuable.
> DEBUG ((DEBUG_INFO, "Board Rev: 0x%lX\n", mBoardRevision));
> - DEBUG ((DEBUG_INFO, "Base RAM : 0x%ll08X (Size 0x%ll08X)\n", mSystemMemoryBase, mSystemMemoryEnd + 1));
> + DEBUG ((DEBUG_INFO, "RAM below 1GB: 0x%ll08X (Size 0x%ll08X)\n", mSystemMemoryBase, mSystemMemoryEnd + 1));
The whole point of using "Base RAM :" was to preserve alignment, as the
expectation is that people reading this debug info output know what it's
about.
> DEBUG ((DEBUG_INFO, "VideoCore: 0x%ll08X (Size 0x%ll08X)\n", mVideoCoreBase, mVideoCoreSize));
>
> ASSERT (mSystemMemoryBase == 0);
> ASSERT (VirtualMemoryMap != NULL);
>
> + // Compute the total RAM size available on this platform
> + TotalMemorySize = SIZE_256MB;
> + TotalMemorySize <<= (mBoardRevision >> 20) & 0x07;
> + DEBUG ((DEBUG_INFO, "Total RAM: 0x%ll08X\n", TotalMemorySize));
> +
> + //
> + // Ensure that what we declare as System Memory doesn't overlap with the
> + // SoC MMIO registers. This can be achieved through a MIN () with the
> + // base address since SystemMemoryBase is 0 (we assert if it isn't).
> + //
> + ASSERT (BCM2836_SOC_REGISTERS < 4UL * SIZE_1GB);
> + MemorySizeBelow4GB = MIN(TotalMemorySize, 4UL * SIZE_1GB);
> + MemorySizeBelow4GB = MIN(MemorySizeBelow4GB, BCM2836_SOC_REGISTERS);
> + if (BCM2711_SOC_REGISTERS > 0) {
> + ASSERT (BCM2836_SOC_REGISTERS < 4UL * SIZE_1GB);
> + MemorySizeBelow4GB = MIN(MemorySizeBelow4GB, BCM2711_SOC_REGISTERS);
> + }
> +
> + //
> + // By default we limit the memory to 3 GB to work around OS support for
> + // DMA bugs in the SoC, for OSes that don't support _DMA range descriptors.
> + // On boards with more RAM (4GB, 8GB), the extra memory is added by ConfigDxe
> + // provided the configuration setting for 3GB limit is off.
> + //
> + MemorySizeBelow3GB = MIN(MemorySizeBelow4GB, 3UL * SIZE_1GB);
> +
> + //
> + // On Pi 3 we've seen SoC registers may overlap the reported VideoCore range,
> + // so clamp that down as well.
> + //
> + if (mVideoCoreBase + mVideoCoreSize > BCM2836_SOC_REGISTERS) {
> + mVideoCoreSize = BCM2836_SOC_REGISTERS - mVideoCoreBase;
> + DEBUG ((DEBUG_WARN, "VideoCore range overlapped SoC MMIO, now 0x%ll08X (Size 0x%ll08X)\n",
> + mVideoCoreBase, mVideoCoreSize));
> + }
> +
> VirtualMemoryTable = (ARM_MEMORY_REGION_DESCRIPTOR*)AllocatePages
> (EFI_SIZE_TO_PAGES (sizeof (ARM_MEMORY_REGION_DESCRIPTOR) *
> MAX_VIRTUAL_MEMORY_MAP_DESCRIPTORS));
> @@ -77,7 +114,6 @@ ArmPlatformGetVirtualMemoryMap (
> return;
> }
>
> -
> // Firmware Volume
> VirtualMemoryTable[Index].PhysicalBase = FixedPcdGet64 (PcdFdBaseAddress);
> VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> @@ -134,21 +170,9 @@ ArmPlatformGetVirtualMemoryMap (
> VirtualMemoryInfo[Index].Type = RPI_MEM_UNMAPPED_REGION;
> VirtualMemoryInfo[Index++].Name = L"GPU Reserved";
>
> - // Compute the total RAM size available on this platform
> - SystemMemorySize = SIZE_256MB;
> - SystemMemorySize <<= (mBoardRevision >> 20) & 0x07;
> -
> - //
> - // Ensure that what we declare as System Memory doesn't overlap with the
> - // Bcm2836 SoC registers. This can be achieved through a MIN () with the
> - // base address since SystemMemoryBase is 0 (we assert if it isn't).
> - //
> - SystemMemorySize = MIN(SystemMemorySize, BCM2836_SOC_REGISTERS);
>
> // Extended SoC registers (PCIe, genet, ...)
> if (BCM2711_SOC_REGISTERS > 0) {
> - // Same overlap protection as above for the Bcm2711 SoC registers
> - SystemMemorySize = MIN(SystemMemorySize, BCM2711_SOC_REGISTERS);
> VirtualMemoryTable[Index].PhysicalBase = BCM2711_SOC_REGISTERS;
> VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> VirtualMemoryTable[Index].Length = BCM2711_SOC_REGISTER_LENGTH;
> @@ -159,45 +183,46 @@ ArmPlatformGetVirtualMemoryMap (
>
> // Base SoC registers
> VirtualMemoryTable[Index].PhysicalBase = BCM2836_SOC_REGISTERS;
> - // On the Pi 3 the SoC registers may overlap VideoCore => fix this
> - if (VirtualMemoryTable[GpuIndex].PhysicalBase + VirtualMemoryTable[GpuIndex].Length > VirtualMemoryTable[Index].PhysicalBase) {
> - VirtualMemoryTable[GpuIndex].Length = VirtualMemoryTable[Index].PhysicalBase - VirtualMemoryTable[GpuIndex].PhysicalBase;
> - }
> VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> VirtualMemoryTable[Index].Length = BCM2836_SOC_REGISTER_LENGTH;
> VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_DEVICE;
> VirtualMemoryInfo[Index].Type = RPI_MEM_UNMAPPED_REGION;
> VirtualMemoryInfo[Index++].Name = L"SoC Reserved (283x)";
>
> - //
> - // By default we limit the memory to 3 GB to work around the DMA bugs in the SoC,
> - // for OSes that don't support _DMA range descriptors. On 4GB boards, it's runtime
> - // setting to boot with 4 GB, and the additional 1 GB is added by ConfigDxe.
> - //
> - OrigMemorySize = SystemMemorySize;
> - SystemMemorySize = MIN(SystemMemorySize, 3UL * SIZE_1GB);
>
> - // If we have RAM above the 1 GB mark, declare it
> - if (SystemMemorySize - SIZE_1GB > 0) {
> - VirtualMemoryTable[Index].PhysicalBase = FixedPcdGet64 (PcdExtendedMemoryBase);
> + // Memory in the 1GB - 3GB range is always available.
> + if (MemorySizeBelow3GB - SIZE_1GB > 0) {
> + VirtualMemoryTable[Index].PhysicalBase = SIZE_1GB;
> VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> - VirtualMemoryTable[Index].Length = SystemMemorySize - SIZE_1GB;
> + VirtualMemoryTable[Index].Length = MemorySizeBelow3GB - VirtualMemoryTable[Index].PhysicalBase;
> VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
> VirtualMemoryInfo[Index].Type = RPI_MEM_BASIC_REGION;
> - VirtualMemoryInfo[Index++].Name = L"Extended System RAM below 3 GB";
> + VirtualMemoryInfo[Index++].Name = L"Extended System RAM below 3GB";
> }
>
> //
> - // If we have RAM above 3 GB mark, declare it so it's mapped, but
> - // don't add it to the memory map. This is done later by ConfigDxe if necessary.
> + // If we have RAM in the 3GB - 4GB range, declare it as mapped, but don't
> + // add it to the memory map. This is done later by ConfigDxe if necessary.
> //
> - if (OrigMemorySize > (3UL * SIZE_1GB)) {
> + if (MemorySizeBelow4GB - 3UL * SIZE_1GB > 0) {
Same comment as for the assert above. The CPU is more than capable to
peform the subtraction for the comparison. ;)
> VirtualMemoryTable[Index].PhysicalBase = 3UL * SIZE_1GB;
> VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> - VirtualMemoryTable[Index].Length = OrigMemorySize - VirtualMemoryTable[Index].PhysicalBase;
> + VirtualMemoryTable[Index].Length = MemorySizeBelow4GB - VirtualMemoryTable[Index].PhysicalBase;
> + VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
> + VirtualMemoryInfo[Index].Type = RPI_MEM_UNMAPPED_REGION;
> + VirtualMemoryInfo[Index++].Name = L"Extended System RAM below 4GB";
> + }
> +
> + //
> + // Same treatment for the 4GB - 16GB range.
I'm not seeing anything related to an actual 16 GB limit, and if the Pi
Foundation keep using the scheme of amount of RAM = 256 MB << 3-bit
value, then we could theoretically see 32 GB Pi's.
In other words, I see little point of talking about 16 GB unless there
is an actual 16 GB in effect somewhere (which, if that is the case,
should be documented in a comment). So I would prefer to see a "> 4 GB"
> + //
> + if (TotalMemorySize - 4UL * SIZE_1GB > 0) {
> + VirtualMemoryTable[Index].PhysicalBase = 4UL * SIZE_1GB;
> + VirtualMemoryTable[Index].VirtualBase = VirtualMemoryTable[Index].PhysicalBase;
> + VirtualMemoryTable[Index].Length = TotalMemorySize - VirtualMemoryTable[Index].PhysicalBase;
> VirtualMemoryTable[Index].Attributes = ARM_MEMORY_REGION_ATTRIBUTE_WRITE_BACK;
> VirtualMemoryInfo[Index].Type = RPI_MEM_UNMAPPED_REGION;
> - VirtualMemoryInfo[Index++].Name = L"Extended System RAM above 3 GB";
> + VirtualMemoryInfo[Index++].Name = L"Extended System RAM below 16GB";
Same thing. What was wrong with changing "above 3 GB" to "above 4GB"?
> }
>
> // End of Table
> diff --git a/Platform/RaspberryPi/RPi4/RPi4.dsc b/Platform/RaspberryPi/RPi4/RPi4.dsc
> index cbff9d99..e055f13c 100644
> --- a/Platform/RaspberryPi/RPi4/RPi4.dsc
> +++ b/Platform/RaspberryPi/RPi4/RPi4.dsc
> @@ -403,7 +403,6 @@
> #
> # Device specific addresses
> #
> - gRaspberryPiTokenSpaceGuid.PcdExtendedMemoryBase|0x40000000
> gBcm27xxTokenSpaceGuid.PcdBcm27xxRegistersAddress|0xfc000000
> gBcm27xxTokenSpaceGuid.PcdBcmGenetRegistersAddress|0xfd580000
> gBcm283xTokenSpaceGuid.PcdBcm283xRegistersAddress|0xfe000000
> diff --git a/Platform/RaspberryPi/RaspberryPi.dec b/Platform/RaspberryPi/RaspberryPi.dec
> index 1a3c44e0..5b402123 100644
> --- a/Platform/RaspberryPi/RaspberryPi.dec
> +++ b/Platform/RaspberryPi/RaspberryPi.dec
> @@ -39,7 +39,6 @@
> gRaspberryPiTokenSpaceGuid.PcdNvStorageVariableBase|0x0|UINT32|0x00000005
> gRaspberryPiTokenSpaceGuid.PcdNvStorageFtwSpareBase|0x0|UINT32|0x00000006
> gRaspberryPiTokenSpaceGuid.PcdNvStorageFtwWorkingBase|0x0|UINT32|0x00000007
> - gRaspberryPiTokenSpaceGuid.PcdExtendedMemoryBase|0x0|UINT32|0x00000008
> gRaspberryPiTokenSpaceGuid.PcdFdtSize|0x10000|UINT32|0x00000009
> gRaspberryPiTokenSpaceGuid.PcdCpuLowSpeedMHz|600|UINT32|0x0000000a
> gRaspberryPiTokenSpaceGuid.PcdCpuDefSpeedMHz|800|UINT32|0x0000000b
>
With the non-blocking remarks above:
Reviewed-by: Pete Batard <pete@akeo.ie>
next prev parent reply other threads:[~2020-06-02 17:52 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-01 9:10 [edk2-platforms][PATCH 1/1] RPi4: reserve/map memory above 4GB when present Andrei Warkentin
2020-06-02 17:52 ` Pete Batard [this message]
-- strict thread matches above, loose matches on Subject: below --
2020-06-07 7:20 Andrei Warkentin
2020-06-08 16:02 ` Pete Batard
2020-06-08 17:41 ` Ard Biesheuvel
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