--- /dev/null
+/*
+ * FDT related Helper functions used by the EFI stub on multiple
+ * architectures. This should be #included by the EFI stub
+ * implementation files.
+ *
+ * Copyright 2013 Linaro Limited; author Roy Franz
+ *
+ * This file is part of the Linux kernel, and is made available
+ * under the terms of the GNU General Public License version 2.
+ *
+ */
+
+#include <linux/efi.h>
+#include <linux/libfdt.h>
+#include <asm/efi.h>
+
+#include "efistub.h"
+
+efi_status_t update_fdt(efi_system_table_t *sys_table, void *orig_fdt,
+ unsigned long orig_fdt_size,
+ void *fdt, int new_fdt_size, char *cmdline_ptr,
+ u64 initrd_addr, u64 initrd_size,
+ efi_memory_desc_t *memory_map,
+ unsigned long map_size, unsigned long desc_size,
+ u32 desc_ver)
+{
+ int node, prev, num_rsv;
+ int status;
+ u32 fdt_val32;
+ u64 fdt_val64;
+
+ /* Do some checks on provided FDT, if it exists*/
+ if (orig_fdt) {
+ if (fdt_check_header(orig_fdt)) {
+ pr_efi_err(sys_table, "Device Tree header not valid!\n");
+ return EFI_LOAD_ERROR;
+ }
+ /*
+ * We don't get the size of the FDT if we get if from a
+ * configuration table.
+ */
+ if (orig_fdt_size && fdt_totalsize(orig_fdt) > orig_fdt_size) {
+ pr_efi_err(sys_table, "Truncated device tree! foo!\n");
+ return EFI_LOAD_ERROR;
+ }
+ }
+
+ if (orig_fdt)
+ status = fdt_open_into(orig_fdt, fdt, new_fdt_size);
+ else
+ status = fdt_create_empty_tree(fdt, new_fdt_size);
+
+ if (status != 0)
+ goto fdt_set_fail;
+
+ /*
+ * Delete any memory nodes present. We must delete nodes which
+ * early_init_dt_scan_memory may try to use.
+ */
+ prev = 0;
+ for (;;) {
+ const char *type;
+ int len;
+
+ node = fdt_next_node(fdt, prev, NULL);
+ if (node < 0)
+ break;
+
+ type = fdt_getprop(fdt, node, "device_type", &len);
+ if (type && strncmp(type, "memory", len) == 0) {
+ fdt_del_node(fdt, node);
+ continue;
+ }
+
+ prev = node;
+ }
+
+ /*
+ * Delete all memory reserve map entries. When booting via UEFI,
+ * kernel will use the UEFI memory map to find reserved regions.
+ */
+ num_rsv = fdt_num_mem_rsv(fdt);
+ while (num_rsv-- > 0)
+ fdt_del_mem_rsv(fdt, num_rsv);
+
+ node = fdt_subnode_offset(fdt, 0, "chosen");
+ if (node < 0) {
+ node = fdt_add_subnode(fdt, 0, "chosen");
+ if (node < 0) {
+ status = node; /* node is error code when negative */
+ goto fdt_set_fail;
+ }
+ }
+
+ if ((cmdline_ptr != NULL) && (strlen(cmdline_ptr) > 0)) {
+ status = fdt_setprop(fdt, node, "bootargs", cmdline_ptr,
+ strlen(cmdline_ptr) + 1);
+ if (status)
+ goto fdt_set_fail;
+ }
+
+ /* Set initrd address/end in device tree, if present */
+ if (initrd_size != 0) {
+ u64 initrd_image_end;
+ u64 initrd_image_start = cpu_to_fdt64(initrd_addr);
+
+ status = fdt_setprop(fdt, node, "linux,initrd-start",
+ &initrd_image_start, sizeof(u64));
+ if (status)
+ goto fdt_set_fail;
+ initrd_image_end = cpu_to_fdt64(initrd_addr + initrd_size);
+ status = fdt_setprop(fdt, node, "linux,initrd-end",
+ &initrd_image_end, sizeof(u64));
+ if (status)
+ goto fdt_set_fail;
+ }
+
+ /* Add FDT entries for EFI runtime services in chosen node. */
+ node = fdt_subnode_offset(fdt, 0, "chosen");
+ fdt_val64 = cpu_to_fdt64((u64)(unsigned long)sys_table);
+ status = fdt_setprop(fdt, node, "linux,uefi-system-table",
+ &fdt_val64, sizeof(fdt_val64));
+ if (status)
+ goto fdt_set_fail;
+
+ fdt_val64 = cpu_to_fdt64((u64)(unsigned long)memory_map);
+ status = fdt_setprop(fdt, node, "linux,uefi-mmap-start",
+ &fdt_val64, sizeof(fdt_val64));
+ if (status)
+ goto fdt_set_fail;
+
+ fdt_val32 = cpu_to_fdt32(map_size);
+ status = fdt_setprop(fdt, node, "linux,uefi-mmap-size",
+ &fdt_val32, sizeof(fdt_val32));
+ if (status)
+ goto fdt_set_fail;
+
+ fdt_val32 = cpu_to_fdt32(desc_size);
+ status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-size",
+ &fdt_val32, sizeof(fdt_val32));
+ if (status)
+ goto fdt_set_fail;
+
+ fdt_val32 = cpu_to_fdt32(desc_ver);
+ status = fdt_setprop(fdt, node, "linux,uefi-mmap-desc-ver",
+ &fdt_val32, sizeof(fdt_val32));
+ if (status)
+ goto fdt_set_fail;
+
+ /*
+ * Add kernel version banner so stub/kernel match can be
+ * verified.
+ */
+ status = fdt_setprop_string(fdt, node, "linux,uefi-stub-kern-ver",
+ linux_banner);
+ if (status)
+ goto fdt_set_fail;
+
+ return EFI_SUCCESS;
+
+fdt_set_fail:
+ if (status == -FDT_ERR_NOSPACE)
+ return EFI_BUFFER_TOO_SMALL;
+
+ return EFI_LOAD_ERROR;
+}
+
+#ifndef EFI_FDT_ALIGN
+#define EFI_FDT_ALIGN EFI_PAGE_SIZE
+#endif
+
+/*
+ * Allocate memory for a new FDT, then add EFI, commandline, and
+ * initrd related fields to the FDT. This routine increases the
+ * FDT allocation size until the allocated memory is large
+ * enough. EFI allocations are in EFI_PAGE_SIZE granules,
+ * which are fixed at 4K bytes, so in most cases the first
+ * allocation should succeed.
+ * EFI boot services are exited at the end of this function.
+ * There must be no allocations between the get_memory_map()
+ * call and the exit_boot_services() call, so the exiting of
+ * boot services is very tightly tied to the creation of the FDT
+ * with the final memory map in it.
+ */
+
+efi_status_t allocate_new_fdt_and_exit_boot(efi_system_table_t *sys_table,
+ void *handle,
+ unsigned long *new_fdt_addr,
+ unsigned long max_addr,
+ u64 initrd_addr, u64 initrd_size,
+ char *cmdline_ptr,
+ unsigned long fdt_addr,
+ unsigned long fdt_size)
+{
+ unsigned long map_size, desc_size;
+ u32 desc_ver;
+ unsigned long mmap_key;
+ efi_memory_desc_t *memory_map, *runtime_map;
+ unsigned long new_fdt_size;
+ efi_status_t status;
+ int runtime_entry_count = 0;
+
+ /*
+ * Get a copy of the current memory map that we will use to prepare
+ * the input for SetVirtualAddressMap(). We don't have to worry about
+ * subsequent allocations adding entries, since they could not affect
+ * the number of EFI_MEMORY_RUNTIME regions.
+ */
+ status = efi_get_memory_map(sys_table, &runtime_map, &map_size,
+ &desc_size, &desc_ver, &mmap_key);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Unable to retrieve UEFI memory map.\n");
+ return status;
+ }
+
+ pr_efi(sys_table,
+ "Exiting boot services and installing virtual address map...\n");
+
+ /*
+ * Estimate size of new FDT, and allocate memory for it. We
+ * will allocate a bigger buffer if this ends up being too
+ * small, so a rough guess is OK here.
+ */
+ new_fdt_size = fdt_size + EFI_PAGE_SIZE;
+ while (1) {
+ status = efi_high_alloc(sys_table, new_fdt_size, EFI_FDT_ALIGN,
+ new_fdt_addr, max_addr);
+ if (status != EFI_SUCCESS) {
+ pr_efi_err(sys_table, "Unable to allocate memory for new device tree.\n");
+ goto fail;
+ }
+
+ /*
+ * Now that we have done our final memory allocation (and free)
+ * we can get the memory map key needed for
+ * exit_boot_services().
+ */
+ status = efi_get_memory_map(sys_table, &memory_map, &map_size,
+ &desc_size, &desc_ver, &mmap_key);
+ if (status != EFI_SUCCESS)
+ goto fail_free_new_fdt;
+
+ status = update_fdt(sys_table,
+ (void *)fdt_addr, fdt_size,
+ (void *)*new_fdt_addr, new_fdt_size,
+ cmdline_ptr, initrd_addr, initrd_size,
+ memory_map, map_size, desc_size, desc_ver);
+
+ /* Succeeding the first time is the expected case. */
+ if (status == EFI_SUCCESS)
+ break;
+
+ if (status == EFI_BUFFER_TOO_SMALL) {
+ /*
+ * We need to allocate more space for the new
+ * device tree, so free existing buffer that is
+ * too small. Also free memory map, as we will need
+ * to get new one that reflects the free/alloc we do
+ * on the device tree buffer.
+ */
+ efi_free(sys_table, new_fdt_size, *new_fdt_addr);
+ sys_table->boottime->free_pool(memory_map);
+ new_fdt_size += EFI_PAGE_SIZE;
+ } else {
+ pr_efi_err(sys_table, "Unable to constuct new device tree.\n");
+ goto fail_free_mmap;
+ }
+ }
+
+ /*
+ * Update the memory map with virtual addresses. The function will also
+ * populate @runtime_map with copies of just the EFI_MEMORY_RUNTIME
+ * entries so that we can pass it straight into SetVirtualAddressMap()
+ */
+ efi_get_virtmap(memory_map, map_size, desc_size, runtime_map,
+ &runtime_entry_count);
+
+ /* Now we are ready to exit_boot_services.*/
+ status = sys_table->boottime->exit_boot_services(handle, mmap_key);
+
+ if (status == EFI_SUCCESS) {
+ efi_set_virtual_address_map_t *svam;
+
+ /* Install the new virtual address map */
+ svam = sys_table->runtime->set_virtual_address_map;
+ status = svam(runtime_entry_count * desc_size, desc_size,
+ desc_ver, runtime_map);
+
+ /*
+ * We are beyond the point of no return here, so if the call to
+ * SetVirtualAddressMap() failed, we need to signal that to the
+ * incoming kernel but proceed normally otherwise.
+ */
+ if (status != EFI_SUCCESS) {
+ int l;
+
+ /*
+ * Set the virtual address field of all
+ * EFI_MEMORY_RUNTIME entries to 0. This will signal
+ * the incoming kernel that no virtual translation has
+ * been installed.
+ */
+ for (l = 0; l < map_size; l += desc_size) {
+ efi_memory_desc_t *p = (void *)memory_map + l;
+
+ if (p->attribute & EFI_MEMORY_RUNTIME)
+ p->virt_addr = 0;
+ }
+ }
+ return EFI_SUCCESS;
+ }
+
+ pr_efi_err(sys_table, "Exit boot services failed.\n");
+
+fail_free_mmap:
+ sys_table->boottime->free_pool(memory_map);
+
+fail_free_new_fdt:
+ efi_free(sys_table, new_fdt_size, *new_fdt_addr);
+
+fail:
+ sys_table->boottime->free_pool(runtime_map);
+ return EFI_LOAD_ERROR;
+}
+
+void *get_fdt(efi_system_table_t *sys_table, unsigned long *fdt_size)
+{
+ efi_guid_t fdt_guid = DEVICE_TREE_GUID;
+ efi_config_table_t *tables;
+ void *fdt;
+ int i;
+
+ tables = (efi_config_table_t *) sys_table->tables;
+ fdt = NULL;
+
+ for (i = 0; i < sys_table->nr_tables; i++)
+ if (efi_guidcmp(tables[i].guid, fdt_guid) == 0) {
+ fdt = (void *) tables[i].table;
+ if (fdt_check_header(fdt) != 0) {
+ pr_efi_err(sys_table, "Invalid header detected on UEFI supplied FDT, ignoring ...\n");
+ return NULL;
+ }
+ *fdt_size = fdt_totalsize(fdt);
+ break;
+ }
+
+ return fdt;
+}
Code Review / kvmfornfv.git / blobdiff