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authorFrancis Rowe <info@gluglug.org.uk>2014-12-25 16:25:49 (EST)
committer Francis Rowe <info@gluglug.org.uk>2014-12-25 16:25:49 (EST)
commita8b13d23f29a08026eaa308b8b09be7e9d1ff5a6 (patch)
tree0cdc767b9b44b94ca4fbec16bf88496bc4656dd4 /resources/utilities/ich9deblob/src/descriptor/descriptor.c
parent655ac91c5db8818c7cef7e9e44febaf36459d394 (diff)
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ich9deblob: moved src to src/, .o files to obj/
Diffstat (limited to 'resources/utilities/ich9deblob/src/descriptor/descriptor.c')
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diff --git a/resources/utilities/ich9deblob/src/descriptor/descriptor.c b/resources/utilities/ich9deblob/src/descriptor/descriptor.c
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+/*
+ * descriptor/descriptor.c
+ * This file is part of the ich9deblob utility from the libreboot project
+ *
+ * Copyright (C) 2014 Steve Shenton <sgsit@libreboot.org>
+ * Francis Rowe <info@gluglug.org.uk>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * Provide descriptor related functions.
+ */
+
+/* structs describing the data in descriptor region */
+#include "descriptor.h"
+
+/*
+ * ---------------------------------------------------------------------
+ * Descriptor functions
+ * ---------------------------------------------------------------------
+ */
+
+/*
+ * Modify the flash descriptor, to remove the ME/AMT, and disable all other regions
+ * Only Flash Descriptor, Gbe and BIOS regions (BIOS region fills factoryRomSize-12k) are left.
+ * Tested on ThinkPad X200 and X200S. X200T and other GM45 targets may also work.
+ * Also described in docs/hcl/x200_remove_me.html
+ */
+struct DESCRIPTORREGIONRECORD deblobbedDescriptorStructFromFactory(struct DESCRIPTORREGIONRECORD factoryDescriptorStruct, unsigned int factoryRomSize)
+{
+ struct DESCRIPTORREGIONRECORD deblobbedDescriptorStruct;
+ memcpy(&deblobbedDescriptorStruct, &factoryDescriptorStruct, DESCRIPTORREGIONSIZE);
+
+ /*
+ * set number of regions from 4 -> 2 (0 based, so 4 means 5 and 2
+ * means 3. We want 3 regions: descriptor, gbe and bios, in that order)
+ */
+ deblobbedDescriptorStruct.flMaps.flMap0.NR = 2;
+
+ /*
+ * make descriptor writable from OS. This is that the user can run:
+ * sudo ./flashrom -p internal:laptop=force_I_want_a_brick
+ * from the OS, without relying an an external SPI flasher, while
+ * being able to write to the descriptor region (locked by default,
+ * until making the change below):
+ */
+ deblobbedDescriptorStruct.masterAccessSection.flMstr1.fdRegionWriteAccess = 1;
+
+ /* relocate BIOS region and increase size to fill image */
+ deblobbedDescriptorStruct.regionSection.flReg1.BASE = 3; // 3<<FLREGIONBITSHIFT is 12KiB, which is where BIOS region is to begin (after descriptor and gbe)
+ deblobbedDescriptorStruct.regionSection.flReg1.LIMIT = ((factoryRomSize >> FLREGIONBITSHIFT) - 1);
+ /*
+ * ^ for example, 8MB ROM, that's 8388608 bytes.
+ * ^ 8388608>>FLREGIONBITSHIFT (or 8388608/4096) = 2048 bytes
+ * 2048 - 1 = 2047 bytes.
+ * This defines where the final 0x1000 (4KiB) page starts in the flash chip, because the hardware does:
+ * 2047<<FLREGIONBITSHIFT (or 2047*4096) = 8384512 bytes, or 7FF000 bytes
+ * (it can't be 0x7FFFFF because of limited number of bits)
+ */
+
+ /* set ME region size to 0 - the ME is a blob, we don't want it in libreboot */
+ deblobbedDescriptorStruct.regionSection.flReg2.BASE = 0x1FFF; // setting 1FFF means setting size to 0. 1FFF<<FLREGIONBITSHIFT is outside of the ROM image (8MB) size?
+ /* ^ datasheet says to set this to 1FFF, but FFF was previously used and also worked. */
+ deblobbedDescriptorStruct.regionSection.flReg2.LIMIT = 0;
+ /*
+ * ^ 0<<FLREGIONBITSHIFT=0, so basically, the size is 0,
+ * ^ and the base (1FFF>>FLREGIONBITSHIFT) is well outside the higher 8MB range.
+ */
+
+ /* relocate Gbe region to begin at 4KiB (immediately after the flash descriptor) */
+ deblobbedDescriptorStruct.regionSection.flReg3.BASE = 1; // 1<<FLREGIONBITSHIFT is 4096, which is where the Gbe region is to begin (after the descriptor)
+ deblobbedDescriptorStruct.regionSection.flReg3.LIMIT = 2;
+ /*
+ * ^ 2<<FLREGIONBITSHIFT=8192 bytes. So we are set it to size 8KiB after the first 4KiB in the flash chip.
+ */
+
+ /* set Platform region size to 0 - another blob that we don't want */
+ deblobbedDescriptorStruct.regionSection.flReg4.BASE = 0x1FFF; // setting 1FFF means setting size to 0. 1FFF<<FLREGIONBITSHIFT is outside of the ROM image (8MB) size?
+ /* ^ datasheet says to set this to 1FFF, but FFF was previously used and also worked. */
+ deblobbedDescriptorStruct.regionSection.flReg4.LIMIT = 0;
+ /*
+ * ^ 0<<FLREGIONBITSHIFT=0, so basically, the size is 0,
+ * and the base (1FFF>>FLREGIONBITSHIFT) is well outside the higher 8MB range.
+ */
+
+ /* disable ME in ICHSTRAP0 - the ME is a blob, we don't want it in libreboot */
+ deblobbedDescriptorStruct.ichStraps.ichStrap0.meDisable = 1;
+
+ /* disable ME and TPM in MCHSTRAP0 */
+ deblobbedDescriptorStruct.mchStraps.mchStrap0.meDisable = 1; // ME is a blob. not wanted in libreboot.
+ deblobbedDescriptorStruct.mchStraps.mchStrap0.tpmDisable = 1; // not wanted in libreboot
+
+ /*
+ * disable ME, apart from chipset bugfixes (ME region should first be re-enabled above)
+ * This is sort of like the CPU microcode updates, but for the chipset
+ * (commented out below here, since blobs go against libreboot's purpose,
+ * but may be interesting for others)
+ * deblobbedDescriptorStruct.mchStraps.mchStrap0.meAlternateDisable = 1;
+ */
+
+ return deblobbedDescriptorStruct;
+}
+
+/*
+ * ---------------------------------------------------------------------
+ * Debugging functions:
+ * ---------------------------------------------------------------------
+ */
+
+/*
+ * show debugging info: descriptor region boundaries, in a 4KB struct.
+ */
+void printDescriptorRegionLocations(struct DESCRIPTORREGIONRECORD descriptorStruct, char* romName)
+{
+ printf("\n");
+
+ /* Descriptor region */
+ printf(
+ "%s: Descriptor start block: %08x ; Descriptor end block: %08x\n",
+ romName,
+ descriptorStruct.regionSection.flReg0.BASE << FLREGIONBITSHIFT,
+ descriptorStruct.regionSection.flReg0.LIMIT << FLREGIONBITSHIFT
+ );
+
+ /* BIOS region */
+ printf(
+ "%s: BIOS start block: %08x ; BIOS end block: %08x\n",
+ romName,
+ descriptorStruct.regionSection.flReg1.BASE << FLREGIONBITSHIFT,
+ descriptorStruct.regionSection.flReg1.LIMIT << FLREGIONBITSHIFT
+ );
+
+ /* ME region */
+ printf(
+ "%s: ME start block: %08x ; ME end block: %08x\n",
+ romName,
+ descriptorStruct.regionSection.flReg2.BASE << FLREGIONBITSHIFT,
+ descriptorStruct.regionSection.flReg2.LIMIT << FLREGIONBITSHIFT
+ );
+
+ /* GBe region */
+ printf(
+ "%s: GBe start block: %08x ; GBe end block: %08x\n",
+ romName,
+ descriptorStruct.regionSection.flReg3.BASE << FLREGIONBITSHIFT,
+ descriptorStruct.regionSection.flReg3.LIMIT << FLREGIONBITSHIFT
+ );
+
+ /* Platform region */
+ printf(
+ "%s: Platform start block: %08x ; GBe end block: %08x\n",
+ romName,
+ descriptorStruct.regionSection.flReg4.BASE << FLREGIONBITSHIFT,
+ descriptorStruct.regionSection.flReg4.LIMIT << FLREGIONBITSHIFT
+ );
+
+ return;
+}