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-rw-r--r--arch/x86/platform/pvh/enlighten.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/arch/x86/platform/pvh/enlighten.c b/arch/x86/platform/pvh/enlighten.c
new file mode 100644
index 000000000..ed0442e35
--- /dev/null
+++ b/arch/x86/platform/pvh/enlighten.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/acpi.h>
+
+#include <xen/hvc-console.h>
+
+#include <asm/io_apic.h>
+#include <asm/hypervisor.h>
+#include <asm/e820/api.h>
+#include <asm/x86_init.h>
+
+#include <asm/xen/interface.h>
+
+#include <xen/xen.h>
+#include <xen/interface/hvm/start_info.h>
+
+/*
+ * PVH variables.
+ *
+ * pvh_bootparams and pvh_start_info need to live in a data segment since
+ * they are used after startup_{32|64}, which clear .bss, are invoked.
+ */
+struct boot_params __initdata pvh_bootparams;
+struct hvm_start_info __initdata pvh_start_info;
+
+const unsigned int __initconst pvh_start_info_sz = sizeof(pvh_start_info);
+
+static u64 __init pvh_get_root_pointer(void)
+{
+ return pvh_start_info.rsdp_paddr;
+}
+
+/*
+ * Xen guests are able to obtain the memory map from the hypervisor via the
+ * HYPERVISOR_memory_op hypercall.
+ * If we are trying to boot a Xen PVH guest, it is expected that the kernel
+ * will have been configured to provide an override for this routine to do
+ * just that.
+ */
+void __init __weak mem_map_via_hcall(struct boot_params *ptr __maybe_unused)
+{
+ xen_raw_printk("Error: Could not find memory map\n");
+ BUG();
+}
+
+static void __init init_pvh_bootparams(bool xen_guest)
+{
+ if ((pvh_start_info.version > 0) && (pvh_start_info.memmap_entries)) {
+ struct hvm_memmap_table_entry *ep;
+ int i;
+
+ ep = __va(pvh_start_info.memmap_paddr);
+ pvh_bootparams.e820_entries = pvh_start_info.memmap_entries;
+
+ for (i = 0; i < pvh_bootparams.e820_entries ; i++, ep++) {
+ pvh_bootparams.e820_table[i].addr = ep->addr;
+ pvh_bootparams.e820_table[i].size = ep->size;
+ pvh_bootparams.e820_table[i].type = ep->type;
+ }
+ } else if (xen_guest) {
+ mem_map_via_hcall(&pvh_bootparams);
+ } else {
+ /* Non-xen guests are not supported by version 0 */
+ BUG();
+ }
+
+ if (pvh_bootparams.e820_entries < E820_MAX_ENTRIES_ZEROPAGE - 1) {
+ pvh_bootparams.e820_table[pvh_bootparams.e820_entries].addr =
+ ISA_START_ADDRESS;
+ pvh_bootparams.e820_table[pvh_bootparams.e820_entries].size =
+ ISA_END_ADDRESS - ISA_START_ADDRESS;
+ pvh_bootparams.e820_table[pvh_bootparams.e820_entries].type =
+ E820_TYPE_RESERVED;
+ pvh_bootparams.e820_entries++;
+ } else
+ xen_raw_printk("Warning: Can fit ISA range into e820\n");
+
+ pvh_bootparams.hdr.cmd_line_ptr =
+ pvh_start_info.cmdline_paddr;
+
+ /* The first module is always ramdisk. */
+ if (pvh_start_info.nr_modules) {
+ struct hvm_modlist_entry *modaddr =
+ __va(pvh_start_info.modlist_paddr);
+ pvh_bootparams.hdr.ramdisk_image = modaddr->paddr;
+ pvh_bootparams.hdr.ramdisk_size = modaddr->size;
+ }
+
+ /*
+ * See Documentation/x86/boot.rst.
+ *
+ * Version 2.12 supports Xen entry point but we will use default x86/PC
+ * environment (i.e. hardware_subarch 0).
+ */
+ pvh_bootparams.hdr.version = (2 << 8) | 12;
+ pvh_bootparams.hdr.type_of_loader = ((xen_guest ? 0x9 : 0xb) << 4) | 0;
+
+ x86_init.acpi.get_root_pointer = pvh_get_root_pointer;
+}
+
+/*
+ * If we are trying to boot a Xen PVH guest, it is expected that the kernel
+ * will have been configured to provide the required override for this routine.
+ */
+void __init __weak xen_pvh_init(struct boot_params *boot_params)
+{
+ xen_raw_printk("Error: Missing xen PVH initialization\n");
+ BUG();
+}
+
+static void __init hypervisor_specific_init(bool xen_guest)
+{
+ if (xen_guest)
+ xen_pvh_init(&pvh_bootparams);
+}
+
+/*
+ * This routine (and those that it might call) should not use
+ * anything that lives in .bss since that segment will be cleared later.
+ */
+void __init xen_prepare_pvh(void)
+{
+
+ u32 msr = xen_cpuid_base();
+ bool xen_guest = !!msr;
+
+ if (pvh_start_info.magic != XEN_HVM_START_MAGIC_VALUE) {
+ xen_raw_printk("Error: Unexpected magic value (0x%08x)\n",
+ pvh_start_info.magic);
+ BUG();
+ }
+
+ memset(&pvh_bootparams, 0, sizeof(pvh_bootparams));
+
+ hypervisor_specific_init(xen_guest);
+
+ init_pvh_bootparams(xen_guest);
+}