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-rw-r--r--arch/x86/lib/Makefile3
-rw-r--r--arch/x86/lib/bios.c347
-rw-r--r--arch/x86/lib/bios.h98
-rw-r--r--arch/x86/lib/bios_asm.S281
-rw-r--r--arch/x86/lib/bios_interrupts.c217
5 files changed, 946 insertions, 0 deletions
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index e146e64..55de788 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -5,6 +5,9 @@
# SPDX-License-Identifier: GPL-2.0+
#
+obj-y += bios.o
+obj-y += bios_asm.o
+obj-y += bios_interrupts.o
obj-$(CONFIG_CMD_BOOTM) += bootm.o
obj-y += cmd_boot.o
obj-y += gcc.o
diff --git a/arch/x86/lib/bios.c b/arch/x86/lib/bios.c
new file mode 100644
index 0000000..298fca6
--- /dev/null
+++ b/arch/x86/lib/bios.c
@@ -0,0 +1,347 @@
+/*
+ * From Coreboot file device/oprom/realmode/x86.c
+ *
+ * Copyright (C) 2007 Advanced Micro Devices, Inc.
+ * Copyright (C) 2009-2010 coresystems GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+#include <common.h>
+#include <bios_emul.h>
+#include <vbe.h>
+#include <asm/cache.h>
+#include <asm/processor.h>
+#include <asm/i8259.h>
+#include <asm/io.h>
+#include <asm/post.h>
+#include "bios.h"
+
+/* Interrupt handlers for each interrupt the ROM can call */
+static int (*int_handler[256])(void);
+
+/* to have a common register file for interrupt handlers */
+X86EMU_sysEnv _X86EMU_env;
+
+asmlinkage void (*realmode_call)(u32 addr, u32 eax, u32 ebx, u32 ecx, u32 edx,
+ u32 esi, u32 edi);
+
+asmlinkage void (*realmode_interrupt)(u32 intno, u32 eax, u32 ebx, u32 ecx,
+ u32 edx, u32 esi, u32 edi);
+
+static void setup_realmode_code(void)
+{
+ memcpy((void *)REALMODE_BASE, &asm_realmode_code,
+ asm_realmode_code_size);
+
+ /* Ensure the global pointers are relocated properly. */
+ realmode_call = PTR_TO_REAL_MODE(asm_realmode_call);
+ realmode_interrupt = PTR_TO_REAL_MODE(__realmode_interrupt);
+
+ debug("Real mode stub @%x: %d bytes\n", REALMODE_BASE,
+ asm_realmode_code_size);
+}
+
+static void setup_rombios(void)
+{
+ const char date[] = "06/11/99";
+ memcpy((void *)0xffff5, &date, 8);
+
+ const char ident[] = "PCI_ISA";
+ memcpy((void *)0xfffd9, &ident, 7);
+
+ /* system model: IBM-AT */
+ writeb(0xfc, 0xffffe);
+}
+
+static int int_exception_handler(void)
+{
+ /* compatibility shim */
+ struct eregs reg_info = {
+ .eax = M.x86.R_EAX,
+ .ecx = M.x86.R_ECX,
+ .edx = M.x86.R_EDX,
+ .ebx = M.x86.R_EBX,
+ .esp = M.x86.R_ESP,
+ .ebp = M.x86.R_EBP,
+ .esi = M.x86.R_ESI,
+ .edi = M.x86.R_EDI,
+ .vector = M.x86.intno,
+ .error_code = 0,
+ .eip = M.x86.R_EIP,
+ .cs = M.x86.R_CS,
+ .eflags = M.x86.R_EFLG
+ };
+ struct eregs *regs = &reg_info;
+
+ debug("Oops, exception %d while executing option rom\n", regs->vector);
+ cpu_hlt();
+
+ return 0;
+}
+
+static int int_unknown_handler(void)
+{
+ debug("Unsupported software interrupt #0x%x eax 0x%x\n",
+ M.x86.intno, M.x86.R_EAX);
+
+ return -1;
+}
+
+/* setup interrupt handlers for mainboard */
+void bios_set_interrupt_handler(int intnum, int (*int_func)(void))
+{
+ int_handler[intnum] = int_func;
+}
+
+static void setup_interrupt_handlers(void)
+{
+ int i;
+
+ /*
+ * The first 16 int_handler functions are not BIOS services,
+ * but the CPU-generated exceptions ("hardware interrupts")
+ */
+ for (i = 0; i < 0x10; i++)
+ int_handler[i] = &int_exception_handler;
+
+ /* Mark all other int_handler calls as unknown first */
+ for (i = 0x10; i < 0x100; i++) {
+ /* Skip if bios_set_interrupt_handler() isn't called first */
+ if (int_handler[i])
+ continue;
+
+ /*
+ * Now set the default functions that are actually needed
+ * to initialize the option roms. The board may override
+ * these with bios_set_interrupt_handler()
+ */
+ switch (i) {
+ case 0x10:
+ int_handler[0x10] = &int10_handler;
+ break;
+ case 0x12:
+ int_handler[0x12] = &int12_handler;
+ break;
+ case 0x16:
+ int_handler[0x16] = &int16_handler;
+ break;
+ case 0x1a:
+ int_handler[0x1a] = &int1a_handler;
+ break;
+ default:
+ int_handler[i] = &int_unknown_handler;
+ break;
+ }
+ }
+}
+
+static void write_idt_stub(void *target, u8 intnum)
+{
+ unsigned char *codeptr;
+
+ codeptr = (unsigned char *)target;
+ memcpy(codeptr, &__idt_handler, __idt_handler_size);
+ codeptr[3] = intnum; /* modify int# in the code stub. */
+}
+
+static void setup_realmode_idt(void)
+{
+ struct realmode_idt *idts = NULL;
+ int i;
+
+ /*
+ * Copy IDT stub code for each interrupt. This might seem wasteful
+ * but it is really simple
+ */
+ for (i = 0; i < 256; i++) {
+ idts[i].cs = 0;
+ idts[i].offset = 0x1000 + (i * __idt_handler_size);
+ write_idt_stub((void *)((u32)idts[i].offset), i);
+ }
+
+ /*
+ * Many option ROMs use the hard coded interrupt entry points in the
+ * system bios. So install them at the known locations.
+ */
+
+ /* int42 is the relocated int10 */
+ write_idt_stub((void *)0xff065, 0x42);
+ /* BIOS Int 11 Handler F000:F84D */
+ write_idt_stub((void *)0xff84d, 0x11);
+ /* BIOS Int 12 Handler F000:F841 */
+ write_idt_stub((void *)0xff841, 0x12);
+ /* BIOS Int 13 Handler F000:EC59 */
+ write_idt_stub((void *)0xfec59, 0x13);
+ /* BIOS Int 14 Handler F000:E739 */
+ write_idt_stub((void *)0xfe739, 0x14);
+ /* BIOS Int 15 Handler F000:F859 */
+ write_idt_stub((void *)0xff859, 0x15);
+ /* BIOS Int 16 Handler F000:E82E */
+ write_idt_stub((void *)0xfe82e, 0x16);
+ /* BIOS Int 17 Handler F000:EFD2 */
+ write_idt_stub((void *)0xfefd2, 0x17);
+ /* ROM BIOS Int 1A Handler F000:FE6E */
+ write_idt_stub((void *)0xffe6e, 0x1a);
+}
+
+static u8 vbe_get_mode_info(struct vbe_mode_info *mi)
+{
+ u16 buffer_seg;
+ u16 buffer_adr;
+ char *buffer;
+
+ debug("VBE: Getting information about VESA mode %04x\n",
+ mi->video_mode);
+ buffer = PTR_TO_REAL_MODE(asm_realmode_buffer);
+ buffer_seg = (((unsigned long)buffer) >> 4) & 0xff00;
+ buffer_adr = ((unsigned long)buffer) & 0xffff;
+
+ realmode_interrupt(0x10, VESA_GET_MODE_INFO, 0x0000, mi->video_mode,
+ 0x0000, buffer_seg, buffer_adr);
+ memcpy(mi->mode_info_block, buffer, sizeof(struct vbe_mode_info));
+ mi->valid = true;
+
+ return 0;
+}
+
+static u8 vbe_set_mode(struct vbe_mode_info *mi)
+{
+ debug("VBE: Setting VESA mode %#04x\n", mi->video_mode);
+ /* request linear framebuffer mode */
+ mi->video_mode |= (1 << 14);
+ /* request clearing of framebuffer */
+ mi->video_mode &= ~(1 << 15);
+ realmode_interrupt(0x10, VESA_SET_MODE, mi->video_mode,
+ 0x0000, 0x0000, 0x0000, 0x0000);
+
+ return 0;
+}
+
+static void vbe_set_graphics(int vesa_mode, struct vbe_mode_info *mode_info)
+{
+ unsigned char *framebuffer;
+
+ mode_info->video_mode = (1 << 14) | vesa_mode;
+ vbe_get_mode_info(mode_info);
+
+ framebuffer = (unsigned char *)mode_info->vesa.phys_base_ptr;
+ debug("VBE: resolution: %dx%d@%d\n",
+ le16_to_cpu(mode_info->vesa.x_resolution),
+ le16_to_cpu(mode_info->vesa.y_resolution),
+ mode_info->vesa.bits_per_pixel);
+ debug("VBE: framebuffer: %p\n", framebuffer);
+ if (!framebuffer) {
+ debug("VBE: Mode does not support linear framebuffer\n");
+ return;
+ }
+
+ vbe_set_mode(mode_info);
+}
+
+void bios_run_on_x86(pci_dev_t pcidev, unsigned long addr, int vesa_mode,
+ struct vbe_mode_info *mode_info)
+{
+ u32 num_dev;
+
+ num_dev = PCI_BUS(pcidev) << 8 | PCI_DEV(pcidev) << 3 |
+ PCI_FUNC(pcidev);
+
+ /* Needed to avoid exceptions in some ROMs */
+ interrupt_init();
+
+ /* Set up some legacy information in the F segment */
+ setup_rombios();
+
+ /* Set up C interrupt handlers */
+ setup_interrupt_handlers();
+
+ /* Set up real-mode IDT */
+ setup_realmode_idt();
+
+ /* Make sure the code is placed. */
+ setup_realmode_code();
+
+ disable_caches();
+ debug("Calling Option ROM at %lx, pci device %#x...", addr, num_dev);
+
+ /* Option ROM entry point is at OPROM start + 3 */
+ realmode_call(addr + 0x0003, num_dev, 0xffff, 0x0000, 0xffff, 0x0,
+ 0x0);
+ debug("done\n");
+
+ if (vesa_mode != -1)
+ vbe_set_graphics(vesa_mode, mode_info);
+}
+
+asmlinkage int interrupt_handler(u32 intnumber, u32 gsfs, u32 dses,
+ u32 edi, u32 esi, u32 ebp, u32 esp,
+ u32 ebx, u32 edx, u32 ecx, u32 eax,
+ u32 cs_ip, u16 stackflags)
+{
+ u32 ip;
+ u32 cs;
+ u32 flags;
+ int ret = 0;
+
+ ip = cs_ip & 0xffff;
+ cs = cs_ip >> 16;
+ flags = stackflags;
+
+#ifdef CONFIG_REALMODE_DEBUG
+ debug("oprom: INT# 0x%x\n", intnumber);
+ debug("oprom: eax: %08x ebx: %08x ecx: %08x edx: %08x\n",
+ eax, ebx, ecx, edx);
+ debug("oprom: ebp: %08x esp: %08x edi: %08x esi: %08x\n",
+ ebp, esp, edi, esi);
+ debug("oprom: ip: %04x cs: %04x flags: %08x\n",
+ ip, cs, flags);
+ debug("oprom: stackflags = %04x\n", stackflags);
+#endif
+
+ /*
+ * Fetch arguments from the stack and put them to a place
+ * suitable for the interrupt handlers
+ */
+ M.x86.R_EAX = eax;
+ M.x86.R_ECX = ecx;
+ M.x86.R_EDX = edx;
+ M.x86.R_EBX = ebx;
+ M.x86.R_ESP = esp;
+ M.x86.R_EBP = ebp;
+ M.x86.R_ESI = esi;
+ M.x86.R_EDI = edi;
+ M.x86.intno = intnumber;
+ M.x86.R_EIP = ip;
+ M.x86.R_CS = cs;
+ M.x86.R_EFLG = flags;
+
+ /* Call the interrupt handler for this interrupt number */
+ ret = int_handler[intnumber]();
+
+ /*
+ * This code is quite strange...
+ *
+ * Put registers back on the stack. The assembler code will pop them
+ * later. We force (volatile!) changing the values of the parameters
+ * of this function. We know that they stay alive on the stack after
+ * we leave this function.
+ */
+ *(volatile u32 *)&eax = M.x86.R_EAX;
+ *(volatile u32 *)&ecx = M.x86.R_ECX;
+ *(volatile u32 *)&edx = M.x86.R_EDX;
+ *(volatile u32 *)&ebx = M.x86.R_EBX;
+ *(volatile u32 *)&esi = M.x86.R_ESI;
+ *(volatile u32 *)&edi = M.x86.R_EDI;
+ flags = M.x86.R_EFLG;
+
+ /* Pass success or error back to our caller via the CARRY flag */
+ if (ret) {
+ flags &= ~1; /* no error: clear carry */
+ } else {
+ debug("int%02x call returned error\n", intnumber);
+ flags |= 1; /* error: set carry */
+ }
+ *(volatile u16 *)&stackflags = flags;
+
+ return ret;
+}
diff --git a/arch/x86/lib/bios.h b/arch/x86/lib/bios.h
new file mode 100644
index 0000000..8491b4a
--- /dev/null
+++ b/arch/x86/lib/bios.h
@@ -0,0 +1,98 @@
+/*
+ * From Coreboot file device/oprom/realmode/x86.h
+ *
+ * Copyright (C) 2007 Advanced Micro Devices, Inc.
+ * Copyright (C) 2009-2010 coresystems GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#ifndef _X86_LIB_BIOS_H
+#define _X86_LIB_BIOS_H
+
+#define REALMODE_BASE 0x600
+
+#ifdef __ASSEMBLY__
+
+#define PTR_TO_REAL_MODE(x) (x - asm_realmode_code + REALMODE_BASE)
+
+#else
+
+/* Convert a symbol address to our real mode area */
+#define PTR_TO_REAL_MODE(sym)\
+ (void *)(REALMODE_BASE + ((char *)&(sym) - (char *)&asm_realmode_code))
+
+/*
+ * The following symbols cannot be used directly. They need to be fixed up
+ * to point to the correct address location after the code has been copied
+ * to REALMODE_BASE. Absolute symbols are not used because those symbols are
+ * relocated by U-Boot.
+ */
+extern unsigned char asm_realmode_call, __realmode_interrupt;
+extern unsigned char asm_realmode_buffer;
+
+#define DOWNTO8(A) \
+ union { \
+ struct { \
+ union { \
+ struct { \
+ uint8_t A##l; \
+ uint8_t A##h; \
+ } __packed; \
+ uint16_t A##x; \
+ } __packed; \
+ uint16_t h##A##x; \
+ } __packed; \
+ uint32_t e##A##x; \
+ } __packed;
+
+#define DOWNTO16(A) \
+ union { \
+ struct { \
+ uint16_t A; \
+ uint16_t h##A; \
+ } __packed; \
+ uint32_t e##A; \
+ } __packed;
+
+struct eregs {
+ DOWNTO8(a);
+ DOWNTO8(c);
+ DOWNTO8(d);
+ DOWNTO8(b);
+ DOWNTO16(sp);
+ DOWNTO16(bp);
+ DOWNTO16(si);
+ DOWNTO16(di);
+ uint32_t vector;
+ uint32_t error_code;
+ uint32_t eip;
+ uint32_t cs;
+ uint32_t eflags;
+};
+
+struct realmode_idt {
+ u16 offset, cs;
+};
+
+void x86_exception(struct eregs *info);
+
+/* From x86_asm.S */
+extern unsigned char __idt_handler;
+extern unsigned int __idt_handler_size;
+extern unsigned char asm_realmode_code;
+extern unsigned int asm_realmode_code_size;
+
+asmlinkage void (*realmode_call)(u32 addr, u32 eax, u32 ebx, u32 ecx, u32 edx,
+ u32 esi, u32 edi);
+
+asmlinkage void (*realmode_interrupt)(u32 intno, u32 eax, u32 ebx, u32 ecx,
+ u32 edx, u32 esi, u32 edi);
+
+int int10_handler(void);
+int int12_handler(void);
+int int16_handler(void);
+int int1a_handler(void);
+#endif /*__ASSEMBLY__ */
+
+#endif
diff --git a/arch/x86/lib/bios_asm.S b/arch/x86/lib/bios_asm.S
new file mode 100644
index 0000000..4faa70e
--- /dev/null
+++ b/arch/x86/lib/bios_asm.S
@@ -0,0 +1,281 @@
+/*
+ * From coreboot x86_asm.S, cleaned up substantially
+ *
+ * Copyright (C) 2009-2010 coresystems GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <asm/processor.h>
+#include <asm/processor-flags.h>
+#include "bios.h"
+
+#define SEG(segment) $segment * X86_GDT_ENTRY_SIZE
+
+/*
+ * This is the interrupt handler stub code. It gets copied to the IDT and
+ * to some fixed addresses in the F segment. Before the code can used,
+ * it gets patched up by the C function copying it: byte 3 (the $0 in
+ * movb $0, %al) is overwritten with the interrupt numbers.
+ */
+
+ .code16
+ .globl __idt_handler
+__idt_handler:
+ pushal
+ movb $0, %al /* This instruction gets modified */
+ ljmp $0, $__interrupt_handler_16bit
+ .globl __idt_handler_size
+__idt_handler_size:
+ .long . - __idt_handler
+
+.macro setup_registers
+ /* initial register values */
+ movl 44(%ebp), %eax
+ movl %eax, __registers + 0 /* eax */
+ movl 48(%ebp), %eax
+ movl %eax, __registers + 4 /* ebx */
+ movl 52(%ebp), %eax
+ movl %eax, __registers + 8 /* ecx */
+ movl 56(%ebp), %eax
+ movl %eax, __registers + 12 /* edx */
+ movl 60(%ebp), %eax
+ movl %eax, __registers + 16 /* esi */
+ movl 64(%ebp), %eax
+ movl %eax, __registers + 20 /* edi */
+.endm
+
+.macro enter_real_mode
+ /* Activate the right segment descriptor real mode. */
+ ljmp SEG(X86_GDT_ENTRY_16BIT_CS), $PTR_TO_REAL_MODE(1f)
+1:
+.code16
+ /*
+ * Load the segment registers with properly configured segment
+ * descriptors. They will retain these configurations (limits,
+ * writability, etc.) once protected mode is turned off.
+ */
+ mov SEG(X86_GDT_ENTRY_16BIT_DS), %ax
+ mov %ax, %ds
+ mov %ax, %es
+ mov %ax, %fs
+ mov %ax, %gs
+ mov %ax, %ss
+
+ /* Turn off protection */
+ movl %cr0, %eax
+ andl $~X86_CR0_PE, %eax
+ movl %eax, %cr0
+
+ /* Now really going into real mode */
+ ljmp $0, $PTR_TO_REAL_MODE(1f)
+1:
+ /*
+ * Set up a stack: Put the stack at the end of page zero. That way
+ * we can easily share it between real and protected, since the
+ * 16-bit ESP at segment 0 will work for any case.
+ */
+ mov $0x0, %ax
+ mov %ax, %ss
+
+ /* Load 16 bit IDT */
+ xor %ax, %ax
+ mov %ax, %ds
+ lidt __realmode_idt
+
+.endm
+
+.macro prepare_for_irom
+ movl $0x1000, %eax
+ movl %eax, %esp
+
+ /* Initialise registers for option rom lcall */
+ movl __registers + 0, %eax
+ movl __registers + 4, %ebx
+ movl __registers + 8, %ecx
+ movl __registers + 12, %edx
+ movl __registers + 16, %esi
+ movl __registers + 20, %edi
+
+ /* Set all segments to 0x0000, ds to 0x0040 */
+ push %ax
+ xor %ax, %ax
+ mov %ax, %es
+ mov %ax, %fs
+ mov %ax, %gs
+ mov SEG(X86_GDT_ENTRY_16BIT_FLAT_DS), %ax
+ mov %ax, %ds
+ pop %ax
+
+.endm
+
+.macro enter_protected_mode
+ /* Go back to protected mode */
+ movl %cr0, %eax
+ orl $X86_CR0_PE, %eax
+ movl %eax, %cr0
+
+ /* Now that we are in protected mode jump to a 32 bit code segment */
+ data32 ljmp SEG(X86_GDT_ENTRY_32BIT_CS), $PTR_TO_REAL_MODE(1f)
+1:
+ .code32
+ mov SEG(X86_GDT_ENTRY_32BIT_DS), %ax
+ mov %ax, %ds
+ mov %ax, %es
+ mov %ax, %gs
+ mov %ax, %ss
+ mov SEG(X86_GDT_ENTRY_32BIT_FS), %ax
+ mov %ax, %fs
+
+ /* restore proper idt */
+ lidt idt_ptr
+.endm
+
+/*
+ * In order to be independent of U-Boot's position in RAM we relocate a part
+ * of the code to the first megabyte of RAM, so the CPU can use it in
+ * real-mode. This code lives at asm_realmode_code.
+ */
+ .globl asm_realmode_code
+asm_realmode_code:
+
+/* Realmode IDT pointer structure. */
+__realmode_idt = PTR_TO_REAL_MODE(.)
+ .word 1023 /* 16 bit limit */
+ .long 0 /* 24 bit base */
+ .word 0
+
+/* Preserve old stack */
+__stack = PTR_TO_REAL_MODE(.)
+ .long 0
+
+/* Register store for realmode_call and realmode_interrupt */
+__registers = PTR_TO_REAL_MODE(.)
+ .long 0 /* 0 - EAX */
+ .long 0 /* 4 - EBX */
+ .long 0 /* 8 - ECX */
+ .long 0 /* 12 - EDX */
+ .long 0 /* 16 - ESI */
+ .long 0 /* 20 - EDI */
+
+/* 256 byte buffer, used by int10 */
+ .globl asm_realmode_buffer
+asm_realmode_buffer:
+ .skip 256
+
+ .code32
+ .globl asm_realmode_call
+asm_realmode_call:
+ /* save all registers to the stack */
+ pusha
+ pushf
+ movl %esp, __stack
+ movl %esp, %ebp
+
+ /*
+ * This function is called with regparm=0 and we have to skip the
+ * 36 bytes from pushf+pusha. Hence start at 40.
+ * Set up our call instruction.
+ */
+ movl 40(%ebp), %eax
+ mov %ax, __lcall_instr + 1
+ andl $0xffff0000, %eax
+ shrl $4, %eax
+ mov %ax, __lcall_instr + 3
+
+ wbinvd
+
+ setup_registers
+ enter_real_mode
+ prepare_for_irom
+
+__lcall_instr = PTR_TO_REAL_MODE(.)
+ .byte 0x9a
+ .word 0x0000, 0x0000
+
+ enter_protected_mode
+
+ /* restore stack pointer, eflags and register values and exit */
+ movl __stack, %esp
+ popf
+ popa
+ ret
+
+ .globl __realmode_interrupt
+__realmode_interrupt:
+ /* save all registers to the stack and store the stack pointer */
+ pusha
+ pushf
+ movl %esp, __stack
+ movl %esp, %ebp
+
+ /*
+ * This function is called with regparm=0 and we have to skip the
+ * 36 bytes from pushf+pusha. Hence start at 40.
+ * Prepare interrupt calling code.
+ */
+ movl 40(%ebp), %eax
+ movb %al, __intXX_instr + 1 /* intno */
+
+ setup_registers
+ enter_real_mode
+ prepare_for_irom
+
+__intXX_instr = PTR_TO_REAL_MODE(.)
+ .byte 0xcd, 0x00 /* This becomes intXX */
+
+ enter_protected_mode
+
+ /* restore stack pointer, eflags and register values and exit */
+ movl __stack, %esp
+ popf
+ popa
+ ret
+
+/*
+ * This is the 16-bit interrupt entry point called by the IDT stub code.
+ *
+ * Before this code code is called, %eax is pushed to the stack, and the
+ * interrupt number is loaded into %al. On return this function cleans up
+ * for its caller.
+ */
+ .code16
+__interrupt_handler_16bit = PTR_TO_REAL_MODE(.)
+ push %ds
+ push %es
+ push %fs
+ push %gs
+
+ /* Clear DF to not break ABI assumptions */
+ cld
+
+ /*
+ * Clean up the interrupt number. We could do this in the stub, but
+ * it would cost two more bytes per stub entry.
+ */
+ andl $0xff, %eax
+ pushl %eax /* ... and make it the first parameter */
+
+ enter_protected_mode
+
+ /* Call the C interrupt handler */
+ movl $interrupt_handler, %eax
+ call *%eax
+
+ enter_real_mode
+
+ /*
+ * Restore all registers, including those manipulated by the C
+ * handler
+ */
+ popl %eax
+ pop %gs
+ pop %fs
+ pop %es
+ pop %ds
+ popal
+ iret
+
+ .globl asm_realmode_code_size
+asm_realmode_code_size:
+ .long . - asm_realmode_code
diff --git a/arch/x86/lib/bios_interrupts.c b/arch/x86/lib/bios_interrupts.c
new file mode 100644
index 0000000..b0e2ecb
--- /dev/null
+++ b/arch/x86/lib/bios_interrupts.c
@@ -0,0 +1,217 @@
+/*
+ * From Coreboot
+ *
+ * Copyright (C) 2001 Ronald G. Minnich
+ * Copyright (C) 2005 Nick.Barker9@btinternet.com
+ * Copyright (C) 2007-2009 coresystems GmbH
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <common.h>
+#include <asm/pci.h>
+#include "bios_emul.h"
+
+/* errors go in AH. Just set these up so that word assigns will work */
+enum {
+ PCIBIOS_SUCCESSFUL = 0x0000,
+ PCIBIOS_UNSUPPORTED = 0x8100,
+ PCIBIOS_BADVENDOR = 0x8300,
+ PCIBIOS_NODEV = 0x8600,
+ PCIBIOS_BADREG = 0x8700
+};
+
+int int10_handler(void)
+{
+ static u8 cursor_row, cursor_col;
+ int res = 0;
+
+ switch ((M.x86.R_EAX & 0xff00) >> 8) {
+ case 0x01: /* Set cursor shape */
+ res = 1;
+ break;
+ case 0x02: /* Set cursor position */
+ if (cursor_row != ((M.x86.R_EDX >> 8) & 0xff) ||
+ cursor_col >= (M.x86.R_EDX & 0xff)) {
+ debug("\n");
+ }
+ cursor_row = (M.x86.R_EDX >> 8) & 0xff;
+ cursor_col = M.x86.R_EDX & 0xff;
+ res = 1;
+ break;
+ case 0x03: /* Get cursor position */
+ M.x86.R_EAX &= 0x00ff;
+ M.x86.R_ECX = 0x0607;
+ M.x86.R_EDX = (cursor_row << 8) | cursor_col;
+ res = 1;
+ break;
+ case 0x06: /* Scroll up */
+ debug("\n");
+ res = 1;
+ break;
+ case 0x08: /* Get Character and Mode at Cursor Position */
+ M.x86.R_EAX = 0x0f00 | 'A'; /* White on black 'A' */
+ res = 1;
+ break;
+ case 0x09: /* Write Character and attribute */
+ case 0x0e: /* Write Character */
+ debug("%c", M.x86.R_EAX & 0xff);
+ res = 1;
+ break;
+ case 0x0f: /* Get video mode */
+ M.x86.R_EAX = 0x5002; /*80 x 25 */
+ M.x86.R_EBX &= 0x00ff;
+ res = 1;
+ break;
+ default:
+ printf("Unknown INT10 function %04x\n", M.x86.R_EAX & 0xffff);
+ break;
+ }
+ return res;
+}
+
+int int12_handler(void)
+{
+ M.x86.R_EAX = 64 * 1024;
+ return 1;
+}
+
+int int16_handler(void)
+{
+ int res = 0;
+
+ switch ((M.x86.R_EAX & 0xff00) >> 8) {
+ case 0x00: /* Check for Keystroke */
+ M.x86.R_EAX = 0x6120; /* Space Bar, Space */
+ res = 1;
+ break;
+ case 0x01: /* Check for Keystroke */
+ M.x86.R_EFLG |= 1 << 6; /* Zero Flag set (no key available) */
+ res = 1;
+ break;
+ default:
+ printf("Unknown INT16 function %04x\n", M.x86.R_EAX & 0xffff);
+
+break;
+ }
+ return res;
+}
+
+#define PCI_CONFIG_SPACE_TYPE1 (1 << 0)
+#define PCI_SPECIAL_CYCLE_TYPE1 (1 << 4)
+
+int int1a_handler(void)
+{
+ unsigned short func = (unsigned short)M.x86.R_EAX;
+ int retval = 1;
+ unsigned short devid, vendorid, devfn;
+ /* Use short to get rid of gabage in upper half of 32-bit register */
+ short devindex;
+ unsigned char bus;
+ pci_dev_t dev;
+ u32 dword;
+ u16 word;
+ u8 byte, reg;
+
+ switch (func) {
+ case 0xb101: /* PCIBIOS Check */
+ M.x86.R_EDX = 0x20494350; /* ' ICP' */
+ M.x86.R_EAX &= 0xffff0000; /* Clear AH / AL */
+ M.x86.R_EAX |= PCI_CONFIG_SPACE_TYPE1 |
+ PCI_SPECIAL_CYCLE_TYPE1;
+ /*
+ * last bus in the system. Hard code to 255 for now.
+ * dev_enumerate() does not seem to tell us (publically)
+ */
+ M.x86.R_ECX = 0xff;
+ M.x86.R_EDI = 0x00000000; /* protected mode entry */
+ retval = 1;
+ break;
+ case 0xb102: /* Find Device */
+ devid = M.x86.R_ECX;
+ vendorid = M.x86.R_EDX;
+ devindex = M.x86.R_ESI;
+ dev = pci_find_device(vendorid, devid, devindex);
+ if (dev != -1) {
+ unsigned short busdevfn;
+ M.x86.R_EAX &= 0xffff00ff; /* Clear AH */
+ M.x86.R_EAX |= PCIBIOS_SUCCESSFUL;
+ /*
+ * busnum is an unsigned char;
+ * devfn is an int, so we mask it off.
+ */
+ busdevfn = (PCI_BUS(dev) << 8) | PCI_DEV(dev) << 3 |
+ PCI_FUNC(dev);
+ debug("0x%x: return 0x%x\n", func, busdevfn);
+ M.x86.R_EBX = busdevfn;
+ retval = 1;
+ } else {
+ M.x86.R_EAX &= 0xffff00ff; /* Clear AH */
+ M.x86.R_EAX |= PCIBIOS_NODEV;
+ retval = 0;
+ }
+ break;
+ case 0xb10a: /* Read Config Dword */
+ case 0xb109: /* Read Config Word */
+ case 0xb108: /* Read Config Byte */
+ case 0xb10d: /* Write Config Dword */
+ case 0xb10c: /* Write Config Word */
+ case 0xb10b: /* Write Config Byte */
+ devfn = M.x86.R_EBX & 0xff;
+ bus = M.x86.R_EBX >> 8;
+ reg = M.x86.R_EDI;
+ dev = PCI_BDF(bus, devfn >> 3, devfn & 7);
+ if (!dev) {
+ debug("0x%x: BAD DEVICE bus %d devfn 0x%x\n", func,
+ bus, devfn);
+ /* Or are we supposed to return PCIBIOS_NODEV? */
+ M.x86.R_EAX &= 0xffff00ff; /* Clear AH */
+ M.x86.R_EAX |= PCIBIOS_BADREG;
+ retval = 0;
+ return retval;
+ }
+ switch (func) {
+ case 0xb108: /* Read Config Byte */
+ byte = pci_read_config8(dev, reg);
+ M.x86.R_ECX = byte;
+ break;
+ case 0xb109: /* Read Config Word */
+ word = pci_read_config16(dev, reg);
+ M.x86.R_ECX = word;
+ break;
+ case 0xb10a: /* Read Config Dword */
+ dword = pci_read_config32(dev, reg);
+ M.x86.R_ECX = dword;
+ break;
+ case 0xb10b: /* Write Config Byte */
+ byte = M.x86.R_ECX;
+ pci_write_config8(dev, reg, byte);
+ break;
+ case 0xb10c: /* Write Config Word */
+ word = M.x86.R_ECX;
+ pci_write_config16(dev, reg, word);
+ break;
+ case 0xb10d: /* Write Config Dword */
+ dword = M.x86.R_ECX;
+ pci_write_config32(dev, reg, dword);
+ break;
+ }
+
+#ifdef CONFIG_REALMODE_DEBUG
+ debug("0x%x: bus %d devfn 0x%x reg 0x%x val 0x%x\n", func,
+ bus, devfn, reg, M.x86.R_ECX);
+#endif
+ M.x86.R_EAX &= 0xffff00ff; /* Clear AH */
+ M.x86.R_EAX |= PCIBIOS_SUCCESSFUL;
+ retval = 1;
+ break;
+ default:
+ printf("UNSUPPORTED PCIBIOS FUNCTION 0x%x\n", func);
+ M.x86.R_EAX &= 0xffff00ff; /* Clear AH */
+ M.x86.R_EAX |= PCIBIOS_UNSUPPORTED;
+ retval = 0;
+ break;
+ }
+
+ return retval;
+}
generated by cgit v1.1 at 2024-12-28 00:30:03 +0000