From 832709565e76a3f068848964a9c1dac4fa5d21f2 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 17 Nov 2017 11:09:44 +0000 Subject: [PATCH] ArmVirtPkg/PrePi: move DRAM discovery code into PrePi ArmVirtQemuKernel and ArmVirtXen use essentially the same code to retrieve DRAM information from the DT /memory node at early boot, and invoke it via the ArmPlatformPeiBootAction () hook exposed by ArmPlatformLib. Let's move this code into the PrePi implementation these platforms share between them (and not with any other platforms) so we can eliminate another dependency on the messy ArmPlatformLib. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ard Biesheuvel Acked-by: Laszlo Ersek --- ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S | 77 +++++++++++++++- ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S | 71 +++++++++++++++ .../PrePi/ArmVirtPrePiUniCoreRelocatable.inf | 2 + ArmVirtPkg/PrePi/FdtParser.c | 90 +++++++++++++++++++ 4 files changed, 238 insertions(+), 2 deletions(-) create mode 100644 ArmVirtPkg/PrePi/FdtParser.c diff --git a/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S index 7a9c0c3787..3296aedfe9 100644 --- a/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S +++ b/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S @@ -49,8 +49,7 @@ ASM_FUNC(_ModuleEntryPoint) b .Lreloc_loop .Lreloc_done: - // Do early platform specific actions - bl ASM_PFX(ArmPlatformPeiBootAction) + bl ASM_PFX(DiscoverDramFromDt) // Get ID of this CPU in Multicore system bl ASM_PFX(ArmReadMpidr) @@ -140,3 +139,77 @@ _GetStackBase: _NeverReturn: b _NeverReturn + +// VOID +// DiscoverDramFromDt ( +// VOID *DeviceTreeBaseAddress, // passed by loader in x0 +// VOID *ImageBase // passed by FDF trampoline in x1 +// ); +ASM_PFX(DiscoverDramFromDt): + // + // If we are booting from RAM using the Linux kernel boot protocol, x0 will + // point to the DTB image in memory. Otherwise, use the default value defined + // by the platform. + // + cbnz x0, 0f + ldr x0, PcdGet64 (PcdDeviceTreeInitialBaseAddress) + +0:mov x29, x30 // preserve LR + mov x28, x0 // preserve DTB pointer + mov x27, x1 // preserve base of image pointer + + // + // The base of the runtime image has been preserved in x1. Check whether + // the expected magic number can be found in the header. + // + ldr w8, .LArm64LinuxMagic + ldr w9, [x1, #0x38] + cmp w8, w9 + bne .Lout + + // + // + // OK, so far so good. We have confirmed that we likely have a DTB and are + // booting via the arm64 Linux boot protocol. Update the base-of-image PCD + // to the actual relocated value, and add the shift of PcdFdBaseAddress to + // PcdFvBaseAddress as well + // + adr x8, PcdGet64 (PcdFdBaseAddress) + adr x9, PcdGet64 (PcdFvBaseAddress) + ldr x6, [x8] + ldr x7, [x9] + sub x7, x7, x6 + add x7, x7, x1 + str x1, [x8] + str x7, [x9] + + // + // Discover the memory size and offset from the DTB, and record in the + // respective PCDs. This will also return false if a corrupt DTB is + // encountered. Since we are calling a C function, use the window at the + // beginning of the FD image as a temp stack. + // + adr x1, PcdGet64 (PcdSystemMemoryBase) + adr x2, PcdGet64 (PcdSystemMemorySize) + mov sp, x7 + bl FindMemnode + cbz x0, .Lout + + // + // Copy the DTB to the slack space right after the 64 byte arm64/Linux style + // image header at the base of this image (defined in the FDF), and record the + // pointer in PcdDeviceTreeInitialBaseAddress. + // + adr x8, PcdGet64 (PcdDeviceTreeInitialBaseAddress) + add x27, x27, #0x40 + str x27, [x8] + + mov x0, x27 + mov x1, x28 + bl CopyFdt + +.Lout: + ret x29 + +.LArm64LinuxMagic: + .byte 0x41, 0x52, 0x4d, 0x64 diff --git a/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S index eebf660acd..a918c19143 100644 --- a/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S +++ b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S @@ -148,3 +148,74 @@ _GetStackBase: _NeverReturn: b _NeverReturn + +ASM_PFX(ArmPlatformPeiBootAction): + // + // If we are booting from RAM using the Linux kernel boot protocol, r0 will + // point to the DTB image in memory. Otherwise, use the default value defined + // by the platform. + // + teq r0, #0 + bne 0f + LDRL (r0, PcdGet64 (PcdDeviceTreeInitialBaseAddress)) + +0:mov r11, r14 // preserve LR + mov r10, r0 // preserve DTB pointer + mov r9, r1 // preserve base of image pointer + + // + // The base of the runtime image has been preserved in r1. Check whether + // the expected magic number can be found in the header. + // + ldr r8, .LArm32LinuxMagic + ldr r7, [r1, #0x24] + cmp r7, r8 + bne .Lout + + // + // + // OK, so far so good. We have confirmed that we likely have a DTB and are + // booting via the ARM Linux boot protocol. Update the base-of-image PCD + // to the actual relocated value, and add the shift of PcdFdBaseAddress to + // PcdFvBaseAddress as well + // + ADRL (r8, PcdGet64 (PcdFdBaseAddress)) + ADRL (r7, PcdGet64 (PcdFvBaseAddress)) + ldr r6, [r8] + ldr r5, [r7] + sub r5, r5, r6 + add r5, r5, r1 + str r1, [r8] + str r5, [r7] + + // + // Discover the memory size and offset from the DTB, and record in the + // respective PCDs. This will also return false if a corrupt DTB is + // encountered. Since we are calling a C function, use the window at the + // beginning of the FD image as a temp stack. + // + ADRL (r1, PcdGet64 (PcdSystemMemoryBase)) + ADRL (r2, PcdGet64 (PcdSystemMemorySize)) + mov sp, r5 + bl FindMemnode + teq r0, #0 + beq .Lout + + // + // Copy the DTB to the slack space right after the 64 byte arm64/Linux style + // image header at the base of this image (defined in the FDF), and record the + // pointer in PcdDeviceTreeInitialBaseAddress. + // + ADRL (r8, PcdGet64 (PcdDeviceTreeInitialBaseAddress)) + add r9, r9, #0x40 + str r9, [r8] + + mov r0, r9 + mov r1, r10 + bl CopyFdt + +.Lout: + bx r11 + +.LArm32LinuxMagic: + .byte 0x18, 0x28, 0x6f, 0x01 diff --git a/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf b/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf index 5e706934f6..789a896857 100755 --- a/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf +++ b/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf @@ -23,6 +23,7 @@ [Sources] PrePi.c + FdtParser.c [Sources.AArch64] AArch64/ArchPrePi.c @@ -44,6 +45,7 @@ [LibraryClasses] BaseLib DebugLib + FdtLib ArmLib IoLib TimerLib diff --git a/ArmVirtPkg/PrePi/FdtParser.c b/ArmVirtPkg/PrePi/FdtParser.c new file mode 100644 index 0000000000..afdc81a883 --- /dev/null +++ b/ArmVirtPkg/PrePi/FdtParser.c @@ -0,0 +1,90 @@ +/* + * Copyright (c) 2015, Linaro Ltd. All rights reserved. + * + * This program and the accompanying materials + * are licensed and made available under the terms and conditions of the BSD License + * which accompanies this distribution. The full text of the license may be found at + * http://opensource.org/licenses/bsd-license.php + * + * THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + * WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + */ + +#include +#include + +BOOLEAN +FindMemnode ( + IN VOID *DeviceTreeBlob, + OUT UINT64 *SystemMemoryBase, + OUT UINT64 *SystemMemorySize + ) +{ + INT32 MemoryNode; + INT32 AddressCells; + INT32 SizeCells; + INT32 Length; + CONST INT32 *Prop; + + if (fdt_check_header (DeviceTreeBlob) != 0) { + return FALSE; + } + + // + // Look for a node called "memory" at the lowest level of the tree + // + MemoryNode = fdt_path_offset (DeviceTreeBlob, "/memory"); + if (MemoryNode <= 0) { + return FALSE; + } + + // + // Retrieve the #address-cells and #size-cells properties + // from the root node, or use the default if not provided. + // + AddressCells = 1; + SizeCells = 1; + + Prop = fdt_getprop (DeviceTreeBlob, 0, "#address-cells", &Length); + if (Length == 4) { + AddressCells = fdt32_to_cpu (*Prop); + } + + Prop = fdt_getprop (DeviceTreeBlob, 0, "#size-cells", &Length); + if (Length == 4) { + SizeCells = fdt32_to_cpu (*Prop); + } + + // + // Now find the 'reg' property of the /memory node, and read the first + // range listed. + // + Prop = fdt_getprop (DeviceTreeBlob, MemoryNode, "reg", &Length); + + if (Length < (AddressCells + SizeCells) * sizeof (INT32)) { + return FALSE; + } + + *SystemMemoryBase = fdt32_to_cpu (Prop[0]); + if (AddressCells > 1) { + *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]); + } + Prop += AddressCells; + + *SystemMemorySize = fdt32_to_cpu (Prop[0]); + if (SizeCells > 1) { + *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]); + } + + return TRUE; +} + +VOID +CopyFdt ( + IN VOID *FdtDest, + IN VOID *FdtSource + ) +{ + fdt_pack(FdtSource); + CopyMem (FdtDest, FdtSource, fdt_totalsize (FdtSource)); +} -- 2.39.2