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| author | Kevin O'Connor <kevin@koconnor.net> | 2008-11-16 09:17:02 -0500 |
|---|---|---|
| committer | Kevin O'Connor <kevin@koconnor.net> | 2008-11-16 09:17:02 -0500 |
| commit | d9a8b2dfef3eeed05a6f4e958bd327ac9a593b38 (patch) | |
| tree | fe2d6c446ef22c1d0d51b6828d20dd6f9ea12b9f /src | |
| parent | 8820a10e732c08e5c8224a2f1456a629b9bc5d98 (diff) | |
| download | seabios-d9a8b2dfef3eeed05a6f4e958bd327ac9a593b38.tar.gz | |
Cleanup a20 code.
Fix two apparent bugs - set_a20() returned new status instead of old
status and handle_152402() checked wrong bit.
Add bit definition for the a20 enable bit: A20_ENABLE_BIT
Allow ioport.h #defines to be used in romlayout.S.
Diffstat (limited to 'src')
| -rw-r--r-- | src/ioport.h | 11 | ||||
| -rw-r--r-- | src/romlayout.S | 15 | ||||
| -rw-r--r-- | src/system.c | 8 |
3 files changed, 19 insertions, 15 deletions
diff --git a/src/ioport.h b/src/ioport.h index 196fe531..633ed0ed 100644 --- a/src/ioport.h +++ b/src/ioport.h @@ -6,8 +6,6 @@ #ifndef __IOPORT_H #define __IOPORT_H -#include "types.h" // u8 - #define PORT_DMA_ADDR_2 0x0004 #define PORT_DMA_CNT_2 0x0005 #define PORT_DMA1_MASK_REG 0x000a @@ -46,9 +44,12 @@ #define PORT_QEMU_CFG_DATA 0x0511 #define PORT_BIOS_APM 0x8900 -// PORT_KBD_CTRLB bitdefs -#define KBD_REFRESH (1<<4) +// PORT_A20 bitdefs +#define A20_ENABLE_BIT 0x02 +#ifndef __ASSEMBLY__ + +#include "types.h" // u8 static inline void outb(u8 value, u16 port) { __asm__ __volatile__("outb %b0, %w1" : : "a"(value), "Nd"(port)); @@ -101,4 +102,6 @@ static inline void outsl(u16 port, u32 *data, u32 count) { : "+c"(count), "+S"(data) : "d"(port) : "memory"); } +#endif // !__ASSEMBLY__ + #endif // ioport.h diff --git a/src/romlayout.S b/src/romlayout.S index f7c2b022..e7c08bc4 100644 --- a/src/romlayout.S +++ b/src/romlayout.S @@ -5,7 +5,8 @@ // // This file may be distributed under the terms of the GNU GPLv3 license. -#include "config.h" +#include "config.h" // CONFIG_* +#include "ioport.h" // PORT_A20 /**************************************************************** @@ -145,9 +146,9 @@ transition32: cli // enable a20 - inb $0x92, %al - orb $0x02, %al - outb %al, $0x92 + inb $PORT_A20, %al + orb $A20_ENABLE_BIT, %al + outb %al, $PORT_A20 // Set segment descriptors lidt %cs:pmode_IDT_info @@ -190,9 +191,9 @@ __call16_from32: movw %ax, %gs // disable a20 - inb $0x92, %al - andb $~0x02, %al - outb %al, $0x92 + inb $PORT_A20, %al + andb $~A20_ENABLE_BIT, %al + outb %al, $PORT_A20 // Jump to 16bit mode ljmpw $SEG32_MODE16_CS, $1f diff --git a/src/system.c b/src/system.c index f4e42635..11b1cc8c 100644 --- a/src/system.c +++ b/src/system.c @@ -19,12 +19,12 @@ set_a20(u8 cond) // get current setting first u8 newval, oldval = inb(PORT_A20); if (cond) - newval = oldval | 0x02; + newval = oldval | A20_ENABLE_BIT; else - newval = oldval & ~0x02; + newval = oldval & ~A20_ENABLE_BIT; outb(newval, PORT_A20); - return (newval & 0x02) != 0; + return (oldval & A20_ENABLE_BIT) != 0; } static void @@ -44,7 +44,7 @@ handle_152401(struct bregs *regs) static void handle_152402(struct bregs *regs) { - regs->al = !!(inb(PORT_A20) & 0x20); + regs->al = (inb(PORT_A20) & A20_ENABLE_BIT) != 0; set_code_success(regs); } |