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-rw-r--r--pc-bios/optionrom/Makefile5
-rw-r--r--pc-bios/optionrom/pvh.S200
-rw-r--r--pc-bios/optionrom/pvh_main.c116
3 files changed, 320 insertions, 1 deletions
diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile
index a9a9e5e7eb..e33a24da0d 100644
--- a/pc-bios/optionrom/Makefile
+++ b/pc-bios/optionrom/Makefile
@@ -37,7 +37,7 @@ Wa = -Wa,
ASFLAGS += -32
QEMU_CFLAGS += $(call cc-c-option, $(QEMU_CFLAGS), $(Wa)-32)
-build-all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin
+build-all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
# suppress auto-removal of intermediate files
.SECONDARY:
@@ -46,6 +46,9 @@ build-all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin
%.o: %.S
$(call quiet-command,$(CPP) $(QEMU_INCLUDES) $(QEMU_DGFLAGS) -c -o - $< | $(AS) $(ASFLAGS) -o $@,"AS","$(TARGET_DIR)$@")
+pvh.img: pvh.o pvh_main.o
+ $(call quiet-command,$(LD) $(LDFLAGS_NOPIE) -m $(LD_I386_EMULATION) -T $(SRC_PATH)/pc-bios/optionrom/flat.lds -s -o $@ $^,"BUILD","$(TARGET_DIR)$@")
+
%.img: %.o
$(call quiet-command,$(LD) $(LDFLAGS_NOPIE) -m $(LD_I386_EMULATION) -T $(SRC_PATH)/pc-bios/optionrom/flat.lds -s -o $@ $<,"BUILD","$(TARGET_DIR)$@")
diff --git a/pc-bios/optionrom/pvh.S b/pc-bios/optionrom/pvh.S
new file mode 100644
index 0000000000..e1d7f4a7a7
--- /dev/null
+++ b/pc-bios/optionrom/pvh.S
@@ -0,0 +1,200 @@
+/*
+ * PVH Option ROM
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright Novell Inc, 2009
+ * Authors: Alexander Graf <agraf@suse.de>
+ *
+ * Copyright (c) 2019 Red Hat Inc.
+ * Authors: Stefano Garzarella <sgarzare@redhat.com>
+ */
+
+#include "optionrom.h"
+
+#define BOOT_ROM_PRODUCT "PVH loader"
+
+#define GS_PROT_JUMP 0
+#define GS_GDT_DESC 6
+
+#ifdef OPTION_ROM_START
+#undef OPTION_ROM_START
+#endif
+#ifdef OPTION_ROM_END
+#undef OPTION_ROM_END
+#endif
+
+/*
+ * Redefine OPTION_ROM_START and OPTION_ROM_END, because this rom is produced
+ * linking multiple objects.
+ * signrom.py will add padding.
+ */
+#define OPTION_ROM_START \
+ .code16; \
+ .text; \
+ .global _start; \
+ _start:; \
+ .short 0xaa55; \
+ .byte 3; /* desired size in 512 units */
+
+#define OPTION_ROM_END \
+ _end:
+
+BOOT_ROM_START
+
+run_pvhboot:
+
+ cli
+ cld
+
+ mov %cs, %eax
+ shl $0x4, %eax
+
+ /* set up a long jump descriptor that is PC relative */
+
+ /* move stack memory to %gs */
+ mov %ss, %ecx
+ shl $0x4, %ecx
+ mov %esp, %ebx
+ add %ebx, %ecx
+ sub $0x20, %ecx
+ sub $0x30, %esp
+ shr $0x4, %ecx
+ mov %cx, %gs
+
+ /* now push the indirect jump descriptor there */
+ mov (prot_jump), %ebx
+ add %eax, %ebx
+ movl %ebx, %gs:GS_PROT_JUMP
+ mov $8, %bx
+ movw %bx, %gs:GS_PROT_JUMP + 4
+
+ /* fix the gdt descriptor to be PC relative */
+ movw (gdt_desc), %bx
+ movw %bx, %gs:GS_GDT_DESC
+ movl (gdt_desc+2), %ebx
+ add %eax, %ebx
+ movl %ebx, %gs:GS_GDT_DESC + 2
+
+ /* initialize HVM memmap table using int 0x15(e820) */
+
+ /* ES = pvh_e820 struct */
+ mov $pvh_e820, %eax
+ shr $4, %eax
+ mov %ax, %es
+
+ /* start storing memmap table at %es:8 (pvh_e820.table) */
+ mov $8,%edi
+ xor %ebx, %ebx
+ jmp memmap_loop
+
+memmap_loop_check:
+ /* pvh_e820 can contains up to 128 entries */
+ cmp $128, %ebx
+ je memmap_done
+
+memmap_loop:
+ /* entry size (hvm_memmap_table_entry) & max buffer size (int15) */
+ movl $24, %ecx
+ /* e820 */
+ movl $0x0000e820, %eax
+ /* 'SMAP' magic */
+ movl $0x534d4150, %edx
+ /* store counter value at %es:0 (pvh_e820.entries) */
+ movl %ebx, %es:0
+
+ int $0x15
+ /* error or last entry already done? */
+ jb memmap_err
+
+ /* %edi += entry size (hvm_memmap_table_entry) */
+ add $24, %edi
+
+ /* continuation value 0 means last entry */
+ test %ebx, %ebx
+ jnz memmap_loop_check
+
+ /* increase pvh_e820.entries to save the last entry */
+ movl %es:0, %ebx
+ inc %ebx
+
+memmap_done:
+ movl %ebx, %es:0
+
+memmap_err:
+
+ /* load the GDT before going into protected mode */
+lgdt:
+ data32 lgdt %gs:GS_GDT_DESC
+
+ /* get us to protected mode now */
+ movl $1, %eax
+ movl %eax, %cr0
+
+ /* the LJMP sets CS for us and gets us to 32-bit */
+ljmp:
+ data32 ljmp *%gs:GS_PROT_JUMP
+
+prot_mode:
+.code32
+
+ /* initialize all other segments */
+ movl $0x10, %eax
+ movl %eax, %ss
+ movl %eax, %ds
+ movl %eax, %es
+ movl %eax, %fs
+ movl %eax, %gs
+
+ jmp pvh_load_kernel
+
+/* Variables */
+.align 4, 0
+prot_jump: .long prot_mode
+ .short 8
+
+.align 4, 0
+gdt:
+ /* 0x00 */
+.byte 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+
+ /*
+ * 0x08: code segment
+ * (base=0, limit=0xfffff, type=32bit code exec/read, DPL=0, 4k)
+ */
+.byte 0xff, 0xff, 0x00, 0x00, 0x00, 0x9a, 0xcf, 0x00
+
+ /*
+ * 0x10: data segment
+ * (base=0, limit=0xfffff, type=32bit data read/write, DPL=0, 4k)
+ */
+.byte 0xff, 0xff, 0x00, 0x00, 0x00, 0x92, 0xcf, 0x00
+
+ /*
+ * 0x18: code segment
+ * (base=0, limit=0x0ffff, type=16bit code exec/read/conf, DPL=0, 1b)
+ */
+.byte 0xff, 0xff, 0x00, 0x00, 0x00, 0x9e, 0x00, 0x00
+
+ /*
+ * 0x20: data segment
+ * (base=0, limit=0x0ffff, type=16bit data read/write, DPL=0, 1b)
+ */
+.byte 0xff, 0xff, 0x00, 0x00, 0x00, 0x92, 0x00, 0x00
+
+gdt_desc:
+.short (5 * 8) - 1
+.long gdt
+
+BOOT_ROM_END
diff --git a/pc-bios/optionrom/pvh_main.c b/pc-bios/optionrom/pvh_main.c
new file mode 100644
index 0000000000..1dcc5c9256
--- /dev/null
+++ b/pc-bios/optionrom/pvh_main.c
@@ -0,0 +1,116 @@
+/*
+ * PVH Option ROM for fw_cfg DMA
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Copyright (c) 2019 Red Hat Inc.
+ * Authors:
+ * Stefano Garzarella <sgarzare@redhat.com>
+ */
+
+asm (".code32"); /* this code will be executed in protected mode */
+
+#include <stddef.h>
+#include <stdint.h>
+#include "optrom.h"
+#include "optrom_fw_cfg.h"
+#include "../../include/hw/xen/start_info.h"
+
+#define RSDP_SIGNATURE 0x2052545020445352LL /* "RSD PTR " */
+#define RSDP_AREA_ADDR 0x000E0000
+#define RSDP_AREA_SIZE 2048
+#define EBDA_BASE_ADDR 0x0000040E
+#define EBDA_SIZE 1024
+
+#define E820_MAXENTRIES 128
+#define CMDLINE_BUFSIZE 4096
+
+/* e820 table filled in pvh.S using int 0x15 */
+struct pvh_e820_table {
+ uint32_t entries;
+ uint32_t reserved;
+ struct hvm_memmap_table_entry table[E820_MAXENTRIES];
+};
+
+struct pvh_e820_table pvh_e820 asm("pvh_e820") __attribute__ ((aligned));
+
+static struct hvm_start_info start_info;
+static uint8_t cmdline_buffer[CMDLINE_BUFSIZE];
+
+
+/* Search RSDP signature. */
+static uintptr_t search_rsdp(uint32_t start_addr, uint32_t end_addr)
+{
+ uint64_t *rsdp_p;
+
+ /* RSDP signature is always on a 16 byte boundary */
+ for (rsdp_p = (uint64_t *)start_addr; rsdp_p < (uint64_t *)end_addr;
+ rsdp_p += 2) {
+ if (*rsdp_p == RSDP_SIGNATURE) {
+ return (uintptr_t)rsdp_p;
+ }
+ }
+
+ return 0;
+}
+
+/* Force the asm name without leading underscore, even on Win32. */
+extern void pvh_load_kernel(void) asm("pvh_load_kernel");
+
+void pvh_load_kernel(void)
+{
+ void *cmdline_addr = &cmdline_buffer;
+ void *kernel_entry;
+ uint32_t cmdline_size, fw_cfg_version = bios_cfg_version();
+
+ start_info.magic = XEN_HVM_START_MAGIC_VALUE;
+ start_info.version = 1;
+
+ /*
+ * pvh_e820 is filled in the pvh.S before to switch in protected mode,
+ * because we can use int 0x15 only in real mode.
+ */
+ start_info.memmap_entries = pvh_e820.entries;
+ start_info.memmap_paddr = (uintptr_t)pvh_e820.table;
+
+ /*
+ * Search RSDP in the main BIOS area below 1 MB.
+ * SeaBIOS store the RSDP in this area, so we try it first.
+ */
+ start_info.rsdp_paddr = search_rsdp(RSDP_AREA_ADDR,
+ RSDP_AREA_ADDR + RSDP_AREA_SIZE);
+
+ /* Search RSDP in the EBDA if it is not found */
+ if (!start_info.rsdp_paddr) {
+ /*
+ * Th EBDA address is stored at EBDA_BASE_ADDR. It contains 2 bytes
+ * segment pointer to EBDA, so we must convert it to a linear address.
+ */
+ uint32_t ebda_paddr = ((uint32_t)*((uint16_t *)EBDA_BASE_ADDR)) << 4;
+ if (ebda_paddr > 0x400) {
+ uint32_t *ebda = (uint32_t *)ebda_paddr;
+
+ start_info.rsdp_paddr = search_rsdp(*ebda, *ebda + EBDA_SIZE);
+ }
+ }
+
+ bios_cfg_read_entry(&cmdline_size, FW_CFG_CMDLINE_SIZE, 4, fw_cfg_version);
+ bios_cfg_read_entry(cmdline_addr, FW_CFG_CMDLINE_DATA, cmdline_size,
+ fw_cfg_version);
+ start_info.cmdline_paddr = (uintptr_t)cmdline_addr;
+
+ bios_cfg_read_entry(&kernel_entry, FW_CFG_KERNEL_ENTRY, 4, fw_cfg_version);
+
+ asm volatile("jmp *%1" : : "b"(&start_info), "c"(kernel_entry));
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-29 16:47:25 +0000