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-rw-r--r--acpi/acpi.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/acpi/acpi.c b/acpi/acpi.c
new file mode 100644
index 00000000..63066aaf
--- /dev/null
+++ b/acpi/acpi.c
@@ -0,0 +1,290 @@
+/*
+ Copyright (C) 2018 Free Software Foundation, Inc.
+
+ This file is part of the GNU Hurd.
+
+ The GNU Hurd 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 2, or (at
+ your option) any later version.
+
+ The GNU Hurd 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 the GNU Hurd. If not, see <<a rel="nofollow" href="http://www.gnu.org/licenses/">http://www.gnu.org/licenses/</a>>.
+*/
+
+#include <sys/mman.h>
+#include <sys/io.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdbool.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "acpi.h"
+
+int
+mmap_phys_acpi_header(uintptr_t base_addr, struct acpi_header **ptr_to_header,
+ void **virt_addr, int fd)
+{
+ /* The memory mapping must be done aligned to page size
+ * but we have a known physical address we want to inspect,
+ * therefore we must compute offsets.
+ */
+ uintptr_t pa_acpi = base_addr & ~(sysconf(_SC_PAGE_SIZE) - 1);
+ uintptr_t pa_start = base_addr - pa_acpi;
+
+ /* Map the ACPI table at the nearest page (rounded down) */
+ *virt_addr = 0;
+ *virt_addr = mmap(NULL, ESCD_SIZE, PROT_READ, MAP_SHARED | MAP_FIXED,
+ fd, (off_t) pa_acpi);
+
+ if (*virt_addr == MAP_FAILED)
+ return errno;
+
+ /* Fabricate a pointer to our magic address */
+ *ptr_to_header = (struct acpi_header *)(*virt_addr + pa_start);
+
+ return 0;
+}
+
+int
+acpi_get_num_tables(size_t *num_tables)
+{
+ int fd_mem;
+ int err;
+ void *virt_addr, *virt_addr2;
+ bool found = false;
+ struct rsdp_descr2 rsdp = { 0 };
+ uintptr_t sdt_base = (uintptr_t)0;
+ bool is_64bit = false;
+ unsigned char *buf;
+ struct acpi_header *root_sdt;
+ struct acpi_header *next;
+
+ if ((fd_mem = open("/dev/mem", O_RDWR)) < 0)
+ return EPERM;
+
+ virt_addr = mmap(NULL, ESCD_SIZE, PROT_READ,
+ MAP_SHARED | MAP_FIXED, fd_mem, ESCD);
+ if (virt_addr == MAP_FAILED)
+ return errno;
+
+ buf = (unsigned char *)virt_addr;
+ found = false;
+
+ /* RSDP magic string is 16 byte aligned */
+ for (int i = 0; i < ESCD_SIZE; i += 16)
+ {
+ if (!memcmp(&buf[i], RSDP_MAGIC, 8)) {
+ rsdp = *((struct rsdp_descr2 *)(&buf[i]));
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ munmap(virt_addr, ESCD_SIZE);
+ return ENODEV;
+ }
+
+ if (rsdp.v1.revision == 0) {
+ // ACPI 1.0
+ sdt_base = rsdp.v1.rsdt_addr;
+ is_64bit = false;
+ } else if (rsdp.v1.revision == 2) {
+ // ACPI >= 2.0
+ sdt_base = rsdp.xsdt_addr;
+ is_64bit = true;
+ } else {
+ munmap(virt_addr, ESCD_SIZE);
+ return ENODEV;
+ }
+
+ munmap(virt_addr, ESCD_SIZE);
+
+ /* Now we have the sdt_base address and knowledge of 32/64 bit ACPI */
+
+ err = mmap_phys_acpi_header(sdt_base, &root_sdt, &virt_addr, fd_mem);
+ if (err) {
+ munmap(virt_addr, ESCD_SIZE);
+ return err;
+ }
+
+ /* Get total tables */
+ uint32_t ntables;
+ uint8_t sz_ptr;
+ sz_ptr = is_64bit ? 8 : 4;
+ ntables = (root_sdt->length - sizeof(*root_sdt)) / sz_ptr;
+
+ /* Get pointer to first ACPI table */
+ uintptr_t acpi_ptr = (uintptr_t)root_sdt + sizeof(*root_sdt);
+
+ /* Get number of readable tables */
+ *num_tables = 0;
+ for (int i = 0; i < ntables; i++)
+ {
+ uintptr_t acpi_ptr32 = (uintptr_t)*((uint32_t *)(acpi_ptr + i*sz_ptr));
+ uintptr_t acpi_ptr64 = (uintptr_t)*((uint64_t *)(acpi_ptr + i*sz_ptr));
+ if (is_64bit) {
+ err = mmap_phys_acpi_header(acpi_ptr64, &next, &virt_addr2, fd_mem);
+ } else {
+ err = mmap_phys_acpi_header(acpi_ptr32, &next, &virt_addr2, fd_mem);
+ }
+
+ char name[5] = { 0 };
+ snprintf(name, 5, "%s", &next->signature[0]);
+ if (next->signature[0] == '\0' || next->length == 0) {
+ munmap(virt_addr2, ESCD_SIZE);
+ continue;
+ }
+ *num_tables += 1;
+ munmap(virt_addr2, ESCD_SIZE);
+ }
+
+ munmap(virt_addr, ESCD_SIZE);
+
+ return 0;
+}
+
+int
+acpi_get_tables(struct acpi_table **tables)
+{
+ int err;
+ int fd_mem;
+ void *virt_addr, *virt_addr2;
+ uint32_t phys_addr = ESCD;
+ bool found = false;
+ struct rsdp_descr2 rsdp = { 0 };
+ uintptr_t sdt_base = (uintptr_t)0;
+ bool is_64bit = false;
+ unsigned char *buf;
+ struct acpi_header *root_sdt;
+ struct acpi_header *next;
+ size_t ntables_actual;
+ int cur_tab = 0;
+
+ err = acpi_get_num_tables(&ntables_actual);
+ if (err)
+ return err;
+
+ *tables = malloc(ntables_actual * sizeof(**tables));
+ if (!*tables)
+ return ENOMEM;
+
+ if ((fd_mem = open("/dev/mem", O_RDWR)) < 0)
+ return EPERM;
+
+ virt_addr = mmap(NULL, ESCD_SIZE, PROT_READ, MAP_SHARED | MAP_FIXED,
+ fd_mem, (off_t) phys_addr);
+
+ if (virt_addr == MAP_FAILED)
+ return errno;
+
+ buf = (unsigned char *)virt_addr;
+ found = false;
+
+ /* RSDP magic string is 16 byte aligned */
+ for (int i = 0; i < ESCD_SIZE; i += 16)
+ {
+ if (!memcmp(&buf[i], RSDP_MAGIC, 8)) {
+ rsdp = *((struct rsdp_descr2 *)(&buf[i]));
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ munmap(virt_addr, ESCD_SIZE);
+ return ENODEV;
+ }
+
+ if (rsdp.v1.revision == 0) {
+ // ACPI 1.0
+ sdt_base = rsdp.v1.rsdt_addr;
+ is_64bit = false;
+ } else if (rsdp.v1.revision == 2) {
+ // ACPI >= 2.0
+ sdt_base = rsdp.xsdt_addr;
+ is_64bit = true;
+ } else {
+ munmap(virt_addr, ESCD_SIZE);
+ return ENODEV;
+ }
+
+ munmap(virt_addr, ESCD_SIZE);
+
+ /* Now we have the sdt_base address and knowledge of 32/64 bit ACPI */
+
+ err = mmap_phys_acpi_header(sdt_base, &root_sdt, &virt_addr, fd_mem);
+ if (err) {
+ munmap(virt_addr, ESCD_SIZE);
+ return err;
+ }
+
+ /* Get total tables */
+ uint32_t ntables;
+ uint8_t sz_ptr;
+ sz_ptr = is_64bit ? 8 : 4;
+ ntables = (root_sdt->length - sizeof(*root_sdt)) / sz_ptr;
+
+ /* Get pointer to first ACPI table */
+ uintptr_t acpi_ptr = (uintptr_t)root_sdt + sizeof(*root_sdt);
+
+ /* Get all tables and data */
+ for (int i = 0; i < ntables; i++)
+ {
+ uintptr_t acpi_ptr32 = (uintptr_t)*((uint32_t *)(acpi_ptr + i*sz_ptr));
+ uintptr_t acpi_ptr64 = (uintptr_t)*((uint64_t *)(acpi_ptr + i*sz_ptr));
+ if (is_64bit) {
+ err = mmap_phys_acpi_header(acpi_ptr64, &next, &virt_addr2, fd_mem);
+ if (err) {
+ munmap(virt_addr, ESCD_SIZE);
+ return err;
+ }
+ } else {
+ err = mmap_phys_acpi_header(acpi_ptr32, &next, &virt_addr2, fd_mem);
+ if (err) {
+ munmap(virt_addr, ESCD_SIZE);
+ return err;
+ }
+ }
+
+ char name[5] = { 0 };
+ snprintf(name, 5, "%s", &next->signature[0]);
+ if (next->signature[0] == '\0' || next->length == 0) {
+ munmap(virt_addr2, ESCD_SIZE);
+ continue;
+ }
+ uint32_t datalen = next->length - sizeof(*next);
+ void *data = (void *)((uintptr_t)next + sizeof(*next));
+
+ /* We now have a pointer to the data,
+ * its length and header.
+ */
+ struct acpi_table *t = *tables + cur_tab;
+ memcpy(&t->h, next, sizeof(*next));
+ t->datalen = 0;
+ t->data = malloc(datalen);
+ if (!t->data) {
+ munmap(virt_addr2, ESCD_SIZE);
+ munmap(virt_addr, ESCD_SIZE);
+ return ENOMEM;
+ }
+ t->datalen = datalen;
+ memcpy(t->data, data, datalen);
+ cur_tab++;
+ munmap(virt_addr2, ESCD_SIZE);
+ }
+
+ munmap(virt_addr, ESCD_SIZE);
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-20 21:57:20 +0000