From c35a4511f715b926852117d30ac106c4709fba26 Mon Sep 17 00:00:00 2001 From: Stefan Reinauer Date: Sat, 24 Oct 2009 17:59:36 +0000 Subject: * refactor x86 smi handler (put all debug stuff in an extra file smiutil.c) * lock other CPUs in SMI handler while one CPU is handling an SMI. Without this various racing scenarios could happen. Signed-off-by: Stefan Reinauer Acked-by: Myles Watson git-svn-id: svn://svn.coreboot.org/coreboot/trunk@4840 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1 --- src/cpu/x86/smm/smihandler.c | 77 ++++++-------------------------------------- 1 file changed, 9 insertions(+), 68 deletions(-) (limited to 'src/cpu/x86/smm/smihandler.c') diff --git a/src/cpu/x86/smm/smihandler.c b/src/cpu/x86/smm/smihandler.c index 96eb589556..7d6dfe4100 100644 --- a/src/cpu/x86/smm/smihandler.c +++ b/src/cpu/x86/smm/smihandler.c @@ -1,7 +1,7 @@ /* * This file is part of the coreboot project. * - * Copyright (C) 2008 coresystems GmbH + * Copyright (C) 2008-2009 coresystems GmbH * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as @@ -27,7 +27,7 @@ void southbridge_smi_set_eos(void); -#define DEBUG_SMI +/* To enable SMI define DEBUG_SMI in smiutil.c */ typedef enum { SMI_LOCKED, SMI_UNLOCKED } smi_semaphore; @@ -67,66 +67,6 @@ static inline __attribute__((always_inline)) unsigned long nodeid(void) return (*((volatile unsigned long *)(LAPIC_ID)) >> 24); } -/* ********************* smi_util ************************* */ - -/* Data */ -#define UART_RBR 0x00 -#define UART_TBR 0x00 - -/* Control */ -#define UART_IER 0x01 -#define UART_IIR 0x02 -#define UART_FCR 0x02 -#define UART_LCR 0x03 -#define UART_MCR 0x04 -#define UART_DLL 0x00 -#define UART_DLM 0x01 - -/* Status */ -#define UART_LSR 0x05 -#define UART_MSR 0x06 -#define UART_SCR 0x07 - -static int uart_can_tx_byte(void) -{ - return inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x20; -} - -static void uart_wait_to_tx_byte(void) -{ - while(!uart_can_tx_byte()) - ; -} - -static void uart_wait_until_sent(void) -{ - while(!(inb(CONFIG_TTYS0_BASE + UART_LSR) & 0x40)) - ; -} - -static void uart_tx_byte(unsigned char data) -{ - uart_wait_to_tx_byte(); - outb(data, CONFIG_TTYS0_BASE + UART_TBR); - /* Make certain the data clears the fifos */ - uart_wait_until_sent(); -} - -void console_tx_flush(void) -{ - uart_wait_to_tx_byte(); -} - -void console_tx_byte(unsigned char byte) -{ - if (byte == '\n') - uart_tx_byte('\r'); - uart_tx_byte(byte); -} - -/* ********************* smi_util ************************* */ - - void io_trap_handler(int smif) { /* If a handler function handled a given IO trap, it @@ -163,16 +103,17 @@ void smi_handler(u32 smm_revision) smm_state_save_area_t state_save; /* Are we ok to execute the handler? */ - if (!smi_obtain_lock()) + if (!smi_obtain_lock()) { + /* For security reasons we don't release the other CPUs + * until the CPU with the lock is actually done + */ + while (smi_handler_status == SMI_LOCKED) /* wait */ ; return; + } node=nodeid(); -#ifdef DEBUG_SMI - console_loglevel = CONFIG_DEFAULT_CONSOLE_LOGLEVEL; -#else - console_loglevel = 1; -#endif + console_init(); printk_spew("\nSMI# #%d\n", node); -- cgit v1.2.3