diff options
Diffstat (limited to 'tools/src/sart.c')
| -rw-r--r-- | tools/src/sart.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/tools/src/sart.c b/tools/src/sart.c new file mode 100644 index 0000000..e0345cd --- /dev/null +++ b/tools/src/sart.c @@ -0,0 +1,219 @@ +/* SPDX-License-Identifier: MIT */ + +#include "adt.h" +#include "malloc.h" +#include "sart.h" +#include "string.h" +#include "utils.h" + +struct sart_dev { + uintptr_t base; + u32 protected_entries; + + void (*get_entry)(sart_dev_t *sart, int index, u8 *flags, void **paddr, size_t *size); + bool (*set_entry)(sart_dev_t *sart, int index, u8 flags, void *paddr, size_t size); +}; + +#define APPLE_SART_MAX_ENTRIES 16 + +/* This is probably a bitfield but the exact meaning of each bit is unknown. */ +#define APPLE_SART_FLAGS_ALLOW 0xff + +/* SARTv2 registers */ +#define APPLE_SART2_CONFIG(idx) (0x00 + 4 * (idx)) +#define APPLE_SART2_CONFIG_FLAGS GENMASK(31, 24) +#define APPLE_SART2_CONFIG_SIZE GENMASK(23, 0) +#define APPLE_SART2_CONFIG_SIZE_SHIFT 12 +#define APPLE_SART2_CONFIG_SIZE_MAX GENMASK(23, 0) + +#define APPLE_SART2_PADDR(idx) (0x40 + 4 * (idx)) +#define APPLE_SART2_PADDR_SHIFT 12 + +/* SARTv3 registers */ +#define APPLE_SART3_CONFIG(idx) (0x00 + 4 * (idx)) + +#define APPLE_SART3_PADDR(idx) (0x40 + 4 * (idx)) +#define APPLE_SART3_PADDR_SHIFT 12 + +#define APPLE_SART3_SIZE(idx) (0x80 + 4 * (idx)) +#define APPLE_SART3_SIZE_SHIFT 12 +#define APPLE_SART3_SIZE_MAX GENMASK(29, 0) + +static void sart2_get_entry(sart_dev_t *sart, int index, u8 *flags, void **paddr, size_t *size) +{ + u32 cfg = read32(sart->base + APPLE_SART2_CONFIG(index)); + *flags = FIELD_GET(APPLE_SART2_CONFIG_FLAGS, cfg); + *size = (size_t)FIELD_GET(APPLE_SART2_CONFIG_SIZE, cfg) << APPLE_SART2_CONFIG_SIZE_SHIFT; + *paddr = + (void *)((u64)read32(sart->base + APPLE_SART2_PADDR(index)) << APPLE_SART2_PADDR_SHIFT); +} + +static bool sart2_set_entry(sart_dev_t *sart, int index, u8 flags, void *paddr_, size_t size) +{ + u32 cfg; + u64 paddr = (u64)paddr_; + + if (size & ((1 << APPLE_SART2_CONFIG_SIZE_SHIFT) - 1)) + return false; + if (paddr & ((1 << APPLE_SART2_PADDR_SHIFT) - 1)) + return false; + + size >>= APPLE_SART2_CONFIG_SIZE_SHIFT; + paddr >>= APPLE_SART2_PADDR_SHIFT; + + if (size > APPLE_SART2_CONFIG_SIZE_MAX) + return false; + + cfg = FIELD_PREP(APPLE_SART2_CONFIG_FLAGS, flags); + cfg |= FIELD_PREP(APPLE_SART2_CONFIG_SIZE, size); + + write32(sart->base + APPLE_SART2_PADDR(index), paddr); + write32(sart->base + APPLE_SART2_CONFIG(index), cfg); + + return true; +} + +static void sart3_get_entry(sart_dev_t *sart, int index, u8 *flags, void **paddr, size_t *size) +{ + *flags = read32(sart->base + APPLE_SART3_CONFIG(index)); + *size = (size_t)read32(sart->base + APPLE_SART3_SIZE(index)) << APPLE_SART3_SIZE_SHIFT; + *paddr = + (void *)((u64)read32(sart->base + APPLE_SART3_PADDR(index)) << APPLE_SART3_PADDR_SHIFT); +} + +static bool sart3_set_entry(sart_dev_t *sart, int index, u8 flags, void *paddr_, size_t size) +{ + u64 paddr = (u64)paddr_; + if (size & ((1 << APPLE_SART3_SIZE_SHIFT) - 1)) + return false; + if (paddr & ((1 << APPLE_SART3_PADDR_SHIFT) - 1)) + return false; + + paddr >>= APPLE_SART3_PADDR_SHIFT; + size >>= APPLE_SART3_SIZE_SHIFT; + + if (size > APPLE_SART3_SIZE_MAX) + return false; + + write32(sart->base + APPLE_SART3_PADDR(index), paddr); + write32(sart->base + APPLE_SART3_SIZE(index), size); + write32(sart->base + APPLE_SART3_CONFIG(index), flags); + + return true; +} + +sart_dev_t *sart_init(const char *adt_path) +{ + int sart_path[8]; + int node = adt_path_offset_trace(adt, adt_path, sart_path); + if (node < 0) { + printf("sart: Error getting SART node %s\n", adt_path); + return NULL; + } + + u64 base; + if (adt_get_reg(adt, sart_path, "reg", 0, &base, NULL) < 0) { + printf("sart: Error getting SART %s base address.\n", adt_path); + return NULL; + } + + const u32 *sart_version = adt_getprop(adt, node, "sart-version", NULL); + if (!sart_version) { + printf("sart: SART %s has no sart-version property\n", adt_path); + return NULL; + } + + sart_dev_t *sart = malloc(sizeof(*sart)); + if (!sart) + return NULL; + + memset(sart, 0, sizeof(*sart)); + sart->base = base; + + switch (*sart_version) { + case 2: + sart->get_entry = sart2_get_entry; + sart->set_entry = sart2_set_entry; + break; + case 3: + sart->get_entry = sart3_get_entry; + sart->set_entry = sart3_set_entry; + break; + default: + printf("sart: SART %s has unknown version %d\n", adt_path, *sart_version); + free(sart); + return NULL; + } + + printf("sart: SARTv%d %s at 0x%lx\n", *sart_version, adt_path, base); + + sart->protected_entries = 0; + for (unsigned int i = 0; i < APPLE_SART_MAX_ENTRIES; ++i) { + void *paddr; + u8 flags; + size_t sz; + + sart->get_entry(sart, i, &flags, &paddr, &sz); + if (flags) + sart->protected_entries |= 1 << i; + } + + return sart; +} + +void sart_free(sart_dev_t *sart) +{ + for (unsigned int i = 0; i < APPLE_SART_MAX_ENTRIES; ++i) { + if (sart->protected_entries & (1 << i)) + continue; + sart->set_entry(sart, i, 0, NULL, 0); + } + + free(sart); +} + +bool sart_add_allowed_region(sart_dev_t *sart, void *paddr, size_t sz) +{ + for (unsigned int i = 0; i < APPLE_SART_MAX_ENTRIES; ++i) { + void *e_paddr; + u8 e_flags; + size_t e_sz; + + if (sart->protected_entries & (1 << i)) + continue; + + sart->get_entry(sart, i, &e_flags, &e_paddr, &e_sz); + if (e_flags) + continue; + + return sart->set_entry(sart, i, APPLE_SART_FLAGS_ALLOW, paddr, sz); + } + + printf("sart: no more free entries\n"); + return false; +} + +bool sart_remove_allowed_region(sart_dev_t *sart, void *paddr, size_t sz) +{ + for (unsigned int i = 0; i < APPLE_SART_MAX_ENTRIES; ++i) { + void *e_paddr; + u8 e_flags; + size_t e_sz; + + if (sart->protected_entries & (1 << i)) + continue; + + sart->get_entry(sart, i, &e_flags, &e_paddr, &e_sz); + if (!e_flags) + continue; + if (e_paddr != paddr) + continue; + if (e_sz != sz) + continue; + + return sart->set_entry(sart, i, 0, NULL, 0); + } + + printf("sart: could not find entry to be removed\n"); + return false; +} |