/* SPDX-License-Identifier: GPL-2.0-or-later */ #include <stdio.h> #include <inttypes.h> #include "intelmetool.h" #include "mmap.h" #include "rcba.h" static const int size = 0x4000; /* Returns the physical RCBA base address or zero on error. */ u32 get_rcba_phys(void) { struct pci_access *pacc; struct pci_dev *sb; uint32_t rcba_phys; pacc = pci_alloc(); pacc->method = PCI_ACCESS_I386_TYPE1; pci_init(pacc); pci_scan_bus(pacc); sb = pci_get_dev(pacc, 0, 0, 0x1f, 0); if (!sb) { printf("Uh oh, southbridge not on BDF(0:31:0), please report " "this error, exiting.\n"); pci_cleanup(pacc); return 0; } pci_fill_info(sb, PCI_FILL_IDENT | PCI_FILL_BASES | PCI_FILL_SIZES | PCI_FILL_CLASS); rcba_phys = pci_read_long(sb, 0xf0) & 0xfffffffe; pci_free_dev(sb); pci_cleanup(pacc); return rcba_phys; } /* * Writes 'val' to RCBA register at address 'addr'. * Returns 1 on error and 0 on success. */ int write_rcba32(uint32_t addr, uint32_t val) { volatile uint8_t *rcba; const uint32_t rcba_phys = get_rcba_phys(); if (!rcba_phys) { printf("Could not get RCBA address\n"); return 1; } rcba = map_physical((off_t)rcba_phys, size); if (rcba == NULL) { printf("Could not map RCBA\n" "Do you have kernel cmdline argument 'iomem=relaxed' set ?\n"); return 1; } *(uint32_t *)(rcba + addr) = val; munmap((void *)rcba, size); return 0; } /* * Reads RCBA register at address 'addr' and stores it in 'val'. * Returns 1 on error and 0 on success. */ int read_rcba32(uint32_t addr, uint32_t *val) { volatile uint8_t *rcba; const uint32_t rcba_phys = get_rcba_phys(); if (!rcba_phys) { printf("Could not get RCBA address\n"); return 1; } rcba = map_physical((off_t)rcba_phys, size); if (rcba == NULL) { printf("Could not map RCBA\n" "Do you have kernel cmdline argument 'iomem=relaxed' set ?\n"); return 1; } *val = *(uint32_t *)(rcba + addr); munmap((void *)rcba, size); return 0; }