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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-11-17 11:09:44 +0000 |
|---|---|---|
| committer | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-11-23 16:05:03 +0000 |
| commit | 832709565e76a3f068848964a9c1dac4fa5d21f2 (patch) | |
| tree | 685643626e5e3da52598f9d656102bec840f0994 /ArmVirtPkg/PrePi/AArch64 | |
| parent | 888559acf98ae954af0418c1f72bc603aa9b9e88 (diff) | |
| download | edk2-832709565e76a3f068848964a9c1dac4fa5d21f2.zip edk2-832709565e76a3f068848964a9c1dac4fa5d21f2.tar.gz edk2-832709565e76a3f068848964a9c1dac4fa5d21f2.tar.bz2 | |
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 <ard.biesheuvel@linaro.org>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Diffstat (limited to 'ArmVirtPkg/PrePi/AArch64')
| -rw-r--r-- | ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S | 77 |
1 files changed, 75 insertions, 2 deletions
diff --git a/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S index 7a9c0c3..3296aed 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
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