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Diffstat (limited to 'hwaccess_physmap.c')
| -rw-r--r-- | hwaccess_physmap.c | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/hwaccess_physmap.c b/hwaccess_physmap.c new file mode 100644 index 000000000..dcc6ed777 --- /dev/null +++ b/hwaccess_physmap.c @@ -0,0 +1,363 @@ +/* + * This file is part of the flashrom project. + * + * Copyright (C) 2009 Peter Stuge <peter@stuge.se> + * Copyright (C) 2009 coresystems GmbH + * Copyright (C) 2010 Carl-Daniel Hailfinger + * Copyright (C) 2010 Rudolf Marek <r.marek@assembler.cz> + * + * 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. + */ + +#include <unistd.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include "flash.h" +#include "hwaccess_physmap.h" + +#if !defined(__DJGPP__) && !defined(__LIBPAYLOAD__) +/* No file access needed/possible to get mmap access permissions or access MSR. */ +#include <sys/stat.h> +#include <fcntl.h> +#endif + +#ifdef __DJGPP__ +#include <dpmi.h> +#include <malloc.h> +#include <sys/nearptr.h> + +#define ONE_MEGABYTE (1024 * 1024) +#define MEM_DEV "dpmi" + +static void *realmem_map_aligned; + +static void *map_first_meg(uintptr_t phys_addr, size_t len) +{ + void *realmem_map; + size_t pagesize; + + if (realmem_map_aligned) + return realmem_map_aligned + phys_addr; + + /* valloc() from DJGPP 2.05 does not work properly */ + pagesize = getpagesize(); + + realmem_map = malloc(ONE_MEGABYTE + pagesize); + + if (!realmem_map) + return ERROR_PTR; + + realmem_map_aligned = (void *)(((size_t) realmem_map + + (pagesize - 1)) & ~(pagesize - 1)); + + if (__djgpp_map_physical_memory(realmem_map_aligned, ONE_MEGABYTE, 0)) { + free(realmem_map); + realmem_map_aligned = NULL; + return ERROR_PTR; + } + + return realmem_map_aligned + phys_addr; +} + +static void *sys_physmap(uintptr_t phys_addr, size_t len) +{ + int ret; + __dpmi_meminfo mi; + + /* Enable 4GB limit on DS descriptor. */ + if (!__djgpp_nearptr_enable()) + return ERROR_PTR; + + if ((phys_addr + len - 1) < ONE_MEGABYTE) { + /* We need to use another method to map first 1MB. */ + return map_first_meg(phys_addr, len); + } + + mi.address = phys_addr; + mi.size = len; + ret = __dpmi_physical_address_mapping(&mi); + + if (ret != 0) + return ERROR_PTR; + + return (void *) mi.address + __djgpp_conventional_base; +} + +#define sys_physmap_rw_uncached sys_physmap +#define sys_physmap_ro_cached sys_physmap + +static void sys_physunmap_unaligned(void *virt_addr, size_t len) +{ + __dpmi_meminfo mi; + + /* There is no known way to unmap the first 1 MB. The DPMI server will + * do this for us on exit. + */ + if ((virt_addr >= realmem_map_aligned) && + ((virt_addr + len) <= (realmem_map_aligned + ONE_MEGABYTE))) { + return; + } + + mi.address = (unsigned long) virt_addr; + __dpmi_free_physical_address_mapping(&mi); +} + +#elif defined(__LIBPAYLOAD__) +#include <arch/virtual.h> + +#define MEM_DEV "" + +void *sys_physmap(uintptr_t phys_addr, size_t len) +{ + return (void *)phys_to_virt(phys_addr); +} + +#define sys_physmap_rw_uncached sys_physmap +#define sys_physmap_ro_cached sys_physmap + +static void sys_physunmap_unaligned(void *virt_addr, size_t len) +{ +} +#elif defined(__MACH__) && defined(__APPLE__) + +#define MEM_DEV "DirectHW" + +static void *sys_physmap(uintptr_t phys_addr, size_t len) +{ + /* The short form of ?: is a GNU extension. + * FIXME: map_physical returns NULL both for errors and for success + * if the region is mapped at virtual address zero. If in doubt, report + * an error until a better interface exists. + */ + return map_physical(phys_addr, len) ? : ERROR_PTR; +} + +/* The OS X driver does not differentiate between mapping types. */ +#define sys_physmap_rw_uncached sys_physmap +#define sys_physmap_ro_cached sys_physmap + +static void sys_physunmap_unaligned(void *virt_addr, size_t len) +{ + unmap_physical(virt_addr, len); +} + +#else +#include <sys/mman.h> + +#if defined (__sun) && (defined(__i386) || defined(__amd64)) +# define MEM_DEV "/dev/xsvc" +#else +# define MEM_DEV "/dev/mem" +#endif + +static int fd_mem = -1; +static int fd_mem_cached = -1; + +/* For MMIO access. Must be uncached, doesn't make sense to restrict to ro. */ +static void *sys_physmap_rw_uncached(uintptr_t phys_addr, size_t len) +{ + void *virt_addr; + + if (-1 == fd_mem) { + /* Open the memory device UNCACHED. Important for MMIO. */ + if (-1 == (fd_mem = open(MEM_DEV, O_RDWR | O_SYNC))) { + msg_perr("Critical error: open(" MEM_DEV "): %s\n", strerror(errno)); + return ERROR_PTR; + } + } + + virt_addr = mmap(NULL, len, PROT_WRITE | PROT_READ, MAP_SHARED, fd_mem, (off_t)phys_addr); + return MAP_FAILED == virt_addr ? ERROR_PTR : virt_addr; +} + +/* For reading DMI/coreboot/whatever tables. We should never write, and we + * do not care about caching. + */ +static void *sys_physmap_ro_cached(uintptr_t phys_addr, size_t len) +{ + void *virt_addr; + + if (-1 == fd_mem_cached) { + /* Open the memory device CACHED. */ + if (-1 == (fd_mem_cached = open(MEM_DEV, O_RDWR))) { + msg_perr("Critical error: open(" MEM_DEV "): %s\n", strerror(errno)); + return ERROR_PTR; + } + } + + virt_addr = mmap(NULL, len, PROT_READ, MAP_SHARED, fd_mem_cached, (off_t)phys_addr); + return MAP_FAILED == virt_addr ? ERROR_PTR : virt_addr; +} + +static void sys_physunmap_unaligned(void *virt_addr, size_t len) +{ + munmap(virt_addr, len); +} +#endif + +#define PHYSM_RW 0 +#define PHYSM_RO 1 +#define PHYSM_NOCLEANUP 0 +#define PHYSM_CLEANUP 1 +#define PHYSM_EXACT 0 +#define PHYSM_ROUND 1 + +/* Round start to nearest page boundary below and set len so that the resulting address range ends at the lowest + * possible page boundary where the original address range is still entirely contained. It returns the + * difference between the rounded start address and the original start address. */ +static uintptr_t round_to_page_boundaries(uintptr_t *start, size_t *len) +{ + uintptr_t page_size = getpagesize(); + uintptr_t page_mask = ~(page_size-1); + uintptr_t end = *start + *len; + uintptr_t old_start = *start; + msg_gspew("page_size=%" PRIxPTR "\n", page_size); + msg_gspew("pre-rounding: start=0x%0*" PRIxPTR ", len=0x%zx, end=0x%0*" PRIxPTR "\n", + PRIxPTR_WIDTH, *start, *len, PRIxPTR_WIDTH, end); + *start = *start & page_mask; + end = (end + page_size - 1) & page_mask; + *len = end - *start; + msg_gspew("post-rounding: start=0x%0*" PRIxPTR ", len=0x%zx, end=0x%0*" PRIxPTR "\n", + PRIxPTR_WIDTH, *start, *len, PRIxPTR_WIDTH, *start + *len); + return old_start - *start; +} + +struct undo_physmap_data { + void *virt_addr; + size_t len; +}; + +static int undo_physmap(void *data) +{ + if (data == NULL) { + msg_perr("%s: tried to physunmap without valid data!\n", __func__); + return 1; + } + struct undo_physmap_data *d = data; + physunmap_unaligned(d->virt_addr, d->len); + free(data); + return 0; +} + +static void *physmap_common(const char *descr, uintptr_t phys_addr, size_t len, bool readonly, bool autocleanup, + bool round) +{ + void *virt_addr; + uintptr_t offset = 0; + + if (len == 0) { + msg_pspew("Not mapping %s, zero size at 0x%0*" PRIxPTR ".\n", descr, PRIxPTR_WIDTH, phys_addr); + return ERROR_PTR; + } + + if (round) + offset = round_to_page_boundaries(&phys_addr, &len); + + if (readonly) + virt_addr = sys_physmap_ro_cached(phys_addr, len); + else + virt_addr = sys_physmap_rw_uncached(phys_addr, len); + + if (ERROR_PTR == virt_addr) { + if (NULL == descr) + descr = "memory"; + msg_perr("Error accessing %s, 0x%zx bytes at 0x%0*" PRIxPTR "\n", + descr, len, PRIxPTR_WIDTH, phys_addr); + msg_perr(MEM_DEV " mmap failed: %s\n", strerror(errno)); +#ifdef __linux__ + if (EINVAL == errno) { + msg_perr("In Linux this error can be caused by the CONFIG_NONPROMISC_DEVMEM (<2.6.27),\n"); + msg_perr("CONFIG_STRICT_DEVMEM (>=2.6.27) and CONFIG_X86_PAT kernel options.\n"); + msg_perr("Please check if either is enabled in your kernel before reporting a failure.\n"); + msg_perr("You can override CONFIG_X86_PAT at boot with the nopat kernel parameter but\n"); + msg_perr("disabling the other option unfortunately requires a kernel recompile. Sorry!\n"); + } +#elif defined (__OpenBSD__) + msg_perr("Please set securelevel=-1 in /etc/rc.securelevel " + "and reboot, or reboot into\n" + "single user mode.\n"); +#endif + return ERROR_PTR; + } + + if (autocleanup) { + struct undo_physmap_data *d = malloc(sizeof(*d)); + if (d == NULL) { + msg_perr("%s: Out of memory!\n", __func__); + physunmap_unaligned(virt_addr, len); + return ERROR_PTR; + } + + d->virt_addr = virt_addr; + d->len = len; + if (register_shutdown(undo_physmap, d) != 0) { + msg_perr("%s: Could not register shutdown function!\n", __func__); + physunmap_unaligned(virt_addr, len); + return ERROR_PTR; + } + } + + return virt_addr + offset; +} + +void physunmap_unaligned(void *virt_addr, size_t len) +{ + /* No need to check for zero size, such mappings would have yielded ERROR_PTR. */ + if (virt_addr == ERROR_PTR) { + msg_perr("Trying to unmap a nonexisting mapping!\n" + "Please report a bug at flashrom@flashrom.org\n"); + return; + } + + sys_physunmap_unaligned(virt_addr, len); +} + +void physunmap(void *virt_addr, size_t len) +{ + uintptr_t tmp; + + /* No need to check for zero size, such mappings would have yielded ERROR_PTR. */ + if (virt_addr == ERROR_PTR) { + msg_perr("Trying to unmap a nonexisting mapping!\n" + "Please report a bug at flashrom@flashrom.org\n"); + return; + } + tmp = (uintptr_t)virt_addr; + /* We assume that the virtual address of a page-aligned physical address is page-aligned as well. By + * extension, rounding a virtual unaligned address as returned by physmap should yield the same offset + * between rounded and original virtual address as between rounded and original physical address. + */ + round_to_page_boundaries(&tmp, &len); + virt_addr = (void *)tmp; + physunmap_unaligned(virt_addr, len); +} + +void *physmap(const char *descr, uintptr_t phys_addr, size_t len) +{ + return physmap_common(descr, phys_addr, len, PHYSM_RW, PHYSM_NOCLEANUP, PHYSM_ROUND); +} + +void *rphysmap(const char *descr, uintptr_t phys_addr, size_t len) +{ + return physmap_common(descr, phys_addr, len, PHYSM_RW, PHYSM_CLEANUP, PHYSM_ROUND); +} + +void *physmap_ro(const char *descr, uintptr_t phys_addr, size_t len) +{ + return physmap_common(descr, phys_addr, len, PHYSM_RO, PHYSM_NOCLEANUP, PHYSM_ROUND); +} + +void *physmap_ro_unaligned(const char *descr, uintptr_t phys_addr, size_t len) +{ + return physmap_common(descr, phys_addr, len, PHYSM_RO, PHYSM_NOCLEANUP, PHYSM_EXACT); +} |