system76-coreboot/util/inteltool/memory.c

/*
 * inteltool - dump all registers on an Intel CPU + chipset based system.
 *
 * Copyright (C) 2008-2010 by coresystems GmbH
 *
 * 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; version 2 of the License.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */


#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include "inteltool.h"

/*
 * (G)MCH MMIO Config Space
 */
int print_mchbar(struct pci_dev *nb, struct pci_access *pacc)
{
	int i, size = (16 * 1024);
	volatile uint8_t *mchbar;
	uint64_t mchbar_phys;
	struct pci_dev *nb_device6; /* "overflow device" on i865 */
	uint16_t pcicmd6;

	printf("\n============= MCHBAR ============\n\n");

	switch (nb->device_id) {
	case PCI_DEVICE_ID_INTEL_82865:
		/*
		 * On i865, the memory access enable/disable bit (MCHBAREN on
		 * i945/i965) is not in the MCHBAR (i945/i965) register but in
		 * the PCICMD6 register. BAR6 and PCICMD6 reside on device 6.
		 *
		 * The actual base address is in BAR6 on i865 where on
		 * i945/i965 the base address is in MCHBAR.
		 */
		nb_device6 = pci_get_dev(pacc, 0, 0, 0x06, 0);  /* Device 6 */
		mchbar_phys = pci_read_long(nb_device6, 0x10);  /* BAR6 */
		pcicmd6 = pci_read_long(nb_device6, 0x04);      /* PCICMD6 */

		/* Try to enable Memory Access Enable (MAE). */
		if (!(pcicmd6 & (1 << 1))) {
			printf("Access to BAR6 is currently disabled, "
			       "attempting to enable.\n");
			pci_write_long(nb_device6, 0x04, pcicmd6 | (1 << 1));
			if (pci_read_long(nb_device6, 0x04) & (1 << 1))
				printf("Enabled successfully.\n");
			else
				printf("Enable FAILED!\n");
		}
		mchbar_phys &= 0xfffff000; /* Bits 31:12 from BAR6 */
		break;
	case PCI_DEVICE_ID_INTEL_82915:
	case PCI_DEVICE_ID_INTEL_82945GM:
	case PCI_DEVICE_ID_INTEL_82945GSE:
	case PCI_DEVICE_ID_INTEL_82945P:
 	case PCI_DEVICE_ID_INTEL_82975X:
		mchbar_phys = pci_read_long(nb, 0x44) & 0xfffffffe;
		break;
 	case PCI_DEVICE_ID_INTEL_PM965:
 	case PCI_DEVICE_ID_INTEL_82Q35:
 	case PCI_DEVICE_ID_INTEL_82G33:
 	case PCI_DEVICE_ID_INTEL_82Q33:
 		mchbar_phys = pci_read_long(nb, 0x48) & 0xfffffffe;
 		mchbar_phys |= ((uint64_t)pci_read_long(nb, 0x4c)) << 32;
 		break;
 	case PCI_DEVICE_ID_INTEL_Q965:
	case PCI_DEVICE_ID_INTEL_ATOM_DXXX:
	case PCI_DEVICE_ID_INTEL_ATOM_NXXX:
 		mchbar_phys = pci_read_long(nb, 0x48);

		/* Test if bit 0 of the MCHBAR reg is 1 to enable memory reads.
		 * If it isn't, try to set it. This may fail, because there is
		 * some bit that locks that bit, and isn't in the public
		 * datasheets.
		 */

		if(!(mchbar_phys & 1))
		{
			printf("Access to the MCHBAR is currently disabled, "\
						"attempting to enable.\n");
			mchbar_phys |= 0x1;
			pci_write_long(nb, 0x48, mchbar_phys);
	 		if(pci_read_long(nb, 0x48) & 1)
				printf("Enabled successfully.\n");
			else
				printf("Enable FAILED!\n");
		}
		mchbar_phys &= 0xfffffffe;
 		mchbar_phys |= ((uint64_t)pci_read_long(nb, 0x4c)) << 32;
 		break;
	case PCI_DEVICE_ID_INTEL_82443LX:
	case PCI_DEVICE_ID_INTEL_82443BX:
	case PCI_DEVICE_ID_INTEL_82810:
	case PCI_DEVICE_ID_INTEL_82810E_MC:
	case PCI_DEVICE_ID_INTEL_82810DC:
	case PCI_DEVICE_ID_INTEL_82830M:
		printf("This northbridge does not have MCHBAR.\n");
		return 1;
	case PCI_DEVICE_ID_INTEL_GS45:
	case PCI_DEVICE_ID_INTEL_X44:
	case PCI_DEVICE_ID_INTEL_32X0:
		mchbar_phys = pci_read_long(nb, 0x48) & 0xfffffffe;
		mchbar_phys |= ((uint64_t)pci_read_long(nb, 0x4c)) << 32;
 		break;
	default:
		printf("Error: Dumping MCHBAR on this northbridge is not (yet) supported.\n");
		return 1;
	}

	mchbar = map_physical(mchbar_phys, size);

	if (mchbar == NULL) {
		if (nb->device_id == PCI_DEVICE_ID_INTEL_82865)
			perror("Error mapping BAR6");
		else
			perror("Error mapping MCHBAR");
		exit(1);
	}

	if (nb->device_id == PCI_DEVICE_ID_INTEL_82865)
		printf("BAR6 = 0x%08" PRIx64 " (MEM)\n\n", mchbar_phys);
	else
		printf("MCHBAR = 0x%08" PRIx64 " (MEM)\n\n", mchbar_phys);

	for (i = 0; i < size; i += 4) {
		if (*(uint32_t *)(mchbar + i))
			printf("0x%04x: 0x%08x\n", i, *(uint32_t *)(mchbar+i));
	}

	unmap_physical((void *)mchbar, size);
	return 0;
}