diff options
| -rw-r--r-- | src/arch/x86/include/librm.h | 20 | ||||
| -rw-r--r-- | src/arch/x86/transitions/librm.S | 67 | ||||
| -rw-r--r-- | src/arch/x86/transitions/librm_mgmt.c | 26 |
3 files changed, 113 insertions, 0 deletions
diff --git a/src/arch/x86/include/librm.h b/src/arch/x86/include/librm.h index 40f075439..84b345d3a 100644 --- a/src/arch/x86/include/librm.h +++ b/src/arch/x86/include/librm.h @@ -474,6 +474,26 @@ extern struct page_table io_pages; */ #define IO_BASE ( ( void * ) 0x100000000ULL ) +/** Startup IPI real-mode handler */ +extern char __text16_array ( sipi, [] ); +#define sipi __use_text16 ( sipi ) + +/** Length of startup IPI real-mode handler */ +extern char sipi_len[]; + +/** Startup IPI real-mode handler copy of real-mode data segment */ +extern uint16_t __text16 ( sipi_ds ); +#define sipi_ds __use_text16 ( sipi_ds ) + +/** Startup IPI protected-mode handler (physical address) */ +extern uint32_t sipi_handler; + +/** Startup IPI register state */ +extern struct i386_regs sipi_regs; + +extern void setup_sipi ( unsigned int vector, uint32_t handler, + struct i386_regs *regs ); + #endif /* ASSEMBLY */ #endif /* LIBRM_H */ diff --git a/src/arch/x86/transitions/librm.S b/src/arch/x86/transitions/librm.S index 394313246..a93b0251f 100644 --- a/src/arch/x86/transitions/librm.S +++ b/src/arch/x86/transitions/librm.S @@ -1632,3 +1632,70 @@ init_pages: /* Return */ ret + +/**************************************************************************** + * sipi (real-mode jump) + * + * Handle Startup IPI + * + * This code must be copied to a page-aligned boundary in base memory. + * It will be entered with %cs:0000 pointing to the start of the code. + * The stack pointer is undefined and so no stack space can be used. + * + **************************************************************************** + */ + .section ".text16.sipi", "ax", @progbits + .code16 + .globl sipi +sipi: + /* Retrieve rm_ds from copy */ + movw %cs:( sipi_ds - sipi ), %ax + movw %ax, %ds + + /* Load GDT and switch to protected mode */ + data32 lgdt gdtr + movl %cr0, %eax + orb $CR0_PE, %al + movl %eax, %cr0 + data32 ljmp $VIRTUAL_CS, $VIRTUAL(1f) + + /* Copy of rm_ds required to access GDT */ + .globl sipi_ds +sipi_ds: + .word 0 + + /* Length of real-mode SIPI handler to be copied */ + .globl sipi_len + .equ sipi_len, . - sipi + + .section ".text.sipi", "ax", @progbits + .code32 +1: /* Set up protected-mode segment registers (with no stack) */ + movw $VIRTUAL_DS, %ax + movw %ax, %ds + movw %ax, %ss + movw $PHYSICAL_DS, %ax + movw %ax, %es + movw %ax, %fs + movw %ax, %gs + + /* Load register state and clear stack pointer */ + movl $VIRTUAL(sipi_regs), %esp + popal + + /* Switch to flat physical addressing */ + movw $PHYSICAL_DS, %sp + movw %sp, %ds + movw %sp, %ss + + /* Clear stack pointer */ + xorl %esp, %esp + + /* Jump to protected-mode SIPI handler */ + ljmp %cs:*VIRTUAL(sipi_handler) + + /* Protected-mode SIPI handler vector */ + .section ".data.sipi_handler", "aw", @progbits + .globl sipi_handler +sipi_handler: + .long 0, PHYSICAL_CS diff --git a/src/arch/x86/transitions/librm_mgmt.c b/src/arch/x86/transitions/librm_mgmt.c index da221e8b1..b3820589c 100644 --- a/src/arch/x86/transitions/librm_mgmt.c +++ b/src/arch/x86/transitions/librm_mgmt.c @@ -45,6 +45,9 @@ struct idtr64 idtr64 = { .limit = ( sizeof ( idt64 ) - 1 ), }; +/** Startup IPI register state */ +struct i386_regs sipi_regs; + /** Length of stack dump */ #define STACK_DUMP_LEN 128 @@ -402,6 +405,29 @@ __asmcall void check_fxsr ( struct i386_all_regs *regs ) { ( ( regs->flags & CF ) ? " not" : "" ) ); } +/** + * Set up startup IPI handler + * + * @v vector Startup IPI vector + * @v handler Protected-mode startup IPI handler physical address + * @v regs Initial register state + */ +void setup_sipi ( unsigned int vector, uint32_t handler, + struct i386_regs *regs ) { + + /* Record protected-mode handler */ + sipi_handler = handler; + + /* Update copy of rm_ds */ + sipi_ds = rm_ds; + + /* Save register state */ + memcpy ( &sipi_regs, regs, sizeof ( sipi_regs ) ); + + /* Copy real-mode handler */ + copy_to_real ( ( vector << 8 ), 0, sipi, ( ( size_t ) sipi_len ) ); +} + PROVIDE_UACCESS_INLINE ( librm, phys_to_user ); PROVIDE_UACCESS_INLINE ( librm, user_to_phys ); PROVIDE_UACCESS_INLINE ( librm, virt_to_user ); |