coreboot-kgpe-d16/payloads/libpayload/drivers/serial/8250.c

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/*
* This file is part of the libpayload project.
*
* Copyright (C) 2008 Advanced Micro Devices, Inc.
* Copyright (C) 2008 Ulf Jordan <jordan@chalmers.se>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <libpayload-config.h>
#include <libpayload.h>
#define IOBASE lib_sysinfo.serial->baseaddr
#define MEMBASE (phys_to_virt(IOBASE))
static int serial_hardware_is_present = 0;
static int serial_is_mem_mapped = 0;
static uint8_t serial_read_reg(int offset)
{
offset *= lib_sysinfo.serial->regwidth;
#ifdef CONFIG_LP_IO_ADDRESS_SPACE
if (!serial_is_mem_mapped)
return inb(IOBASE + offset);
else
#endif
return readb(MEMBASE + offset);
}
static void serial_write_reg(uint8_t val, int offset)
{
offset *= lib_sysinfo.serial->regwidth;
#ifdef CONFIG_LP_IO_ADDRESS_SPACE
if (!serial_is_mem_mapped)
outb(val, IOBASE + offset);
else
#endif
writeb(val, MEMBASE + offset);
}
#ifdef CONFIG_LP_SERIAL_SET_SPEED
static void serial_hardware_init(int speed, int word_bits,
int parity, int stop_bits)
{
unsigned char reg;
/* Disable interrupts. */
serial_write_reg(0, 0x01);
/* Assert RTS and DTR. */
serial_write_reg(3, 0x04);
/* Set the divisor latch. */
reg = serial_read_reg(0x03);
serial_write_reg(reg | 0x80, 0x03);
/* Write the divisor. */
uint16_t divisor = 115200 / speed;
serial_write_reg(divisor & 0xFF, 0x00);
serial_write_reg(divisor >> 8, 0x01);
/* Restore the previous value of the divisor.
* And set 8 bits per character */
serial_write_reg((reg & ~0x80) | 3, 0x03);
}
#endif
static struct console_input_driver consin = {
.havekey = &serial_havechar,
.getchar = &serial_getchar
};
static struct console_output_driver consout = {
.putchar = &serial_putchar
};
void serial_init(void)
{
if (!lib_sysinfo.serial)
return;
serial_is_mem_mapped =
(lib_sysinfo.serial->type == CB_SERIAL_TYPE_MEMORY_MAPPED);
if (!serial_is_mem_mapped) {
#ifdef CONFIG_LP_IO_ADDRESS_SPACE
if ((inb(IOBASE + 0x05) == 0xFF) &&
(inb(IOBASE + 0x06) == 0xFF)) {
printf("IO space mapped serial not present.");
return;
}
#else
printf("IO space mapped serial not supported.");
return;
#endif
}
#ifdef CONFIG_LP_SERIAL_SET_SPEED
serial_hardware_init(CONFIG_LP_SERIAL_BAUD_RATE, 8, 0, 1);
#endif
}
void serial_console_init(void)
{
if (!lib_sysinfo.serial)
return;
serial_init();
console_add_input_driver(&consin);
console_add_output_driver(&consout);
serial_hardware_is_present = 1;
}
void serial_putchar(unsigned int c)
{
if (!serial_hardware_is_present)
return;
while ((serial_read_reg(0x05) & 0x20) == 0) ;
serial_write_reg(c, 0x00);
libpayload: console: Allow output drivers to print whole strings at once The console output driver framework in libpayload is currently built on the putchar primitive, meaning that every driver's function gets called one character at a time. This becomes an issue when we add drivers that could output multiple characters at a time, but have a high constant overhead per invocation (such as the planned GDB stub, which needs to wrap a special frame around output strings and wait for an acknowledgement from the server). This patch adds a new 'write' function pointer to the console_output_driver structure as an alternative to 'putchar'. Output drivers need to provide at least one of the two ('write' is preferred if available). The CBMEM console driver is ported as a proof of concept (since it's our most performace-critical driver and should in theory benefit the most from less function pointer invocations, although it's probably still negligible compared to the big sprawling mess that is printf()). Even with this fix, the problem remains that printf() was written with the putchar primitive in mind. Even though normal text already contains an optimization to allow multiple characters at a time, almost all formatting directives cause their output (including things like padding whitespace) to be putchar()ed one character at a time. Therefore, this patch reworks parts of the output code (especially number printing) to all but remove that inefficiency (directives still invoke an extra write() call, but at least not one per character). Since I'm touching printf() core code anyway, I also tried to salvage what I could from that weird, broken "return negative on error" code path (not that any of our current output drivers can trigger it anyway). A final consequence of this patch is that the responsibility to prepend line feeds with carriage returns is moved into the output driver implementations. Doing this only makes sense for drivers with explicit cursor position control (i.e. serial or video), and things like the CBMEM console that appears like a normal file to the system really have no business containing carriage returns (we don't want people to accidentally associate us with Windows, now, do we?). BUG=chrome-os-partner:18390 TEST=Made sure video and CBMEM console still look good, tried printf() with as many weird edge-case strings as I could find and compared serial output as well as sprintf() return value. Original-Change-Id: Ie05ae489332a0103461620f5348774b6d4afd91a Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/196384 Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org> Original-Reviewed-by: David Hendricks <dhendrix@chromium.org> (cherry picked from commit ab1ef0c07736fe1aa3e0baaf02d258731e6856c0) Signed-off-by: Marc Jones <marc.jones@se-eng.com> Change-Id: I78f5aedf6d0c3665924995cdab691ee0162de404 Reviewed-on: http://review.coreboot.org/7880 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2014-04-18 05:00:20 +02:00
if (c == '\n')
serial_putchar('\r');
}
int serial_havechar(void)
{
if (!serial_hardware_is_present)
return 0;
return serial_read_reg(0x05) & 0x01;
}
int serial_getchar(void)
{
if (!serial_hardware_is_present)
return -1;
while (!serial_havechar()) ;
return serial_read_reg(0x00);
}
/* These are thinly veiled vt100 functions used by curses */
#define VT100_CLEAR "\e[H\e[J"
/* These defines will fail if you use bold and reverse at the same time.
* Switching off one of them will switch off both. tinycurses knows about
* this and does the right thing.
*/
#define VT100_SBOLD "\e[1m"
#define VT100_EBOLD "\e[m"
#define VT100_SREVERSE "\e[7m"
#define VT100_EREVERSE "\e[m"
#define VT100_CURSOR_ADDR "\e[%d;%dH"
#define VT100_CURSOR_ON "\e[?25l"
#define VT100_CURSOR_OFF "\e[?25h"
/* The following smacs/rmacs are actually for xterm; a real vt100 has
enacs=\E(B\E)0, smacs=^N, rmacs=^O. */
#define VT100_SMACS "\e(0"
#define VT100_RMACS "\e(B"
/* A vt100 doesn't do color, setaf/setab below are from xterm-color. */
#define VT100_SET_COLOR "\e[3%d;4%dm"
static void serial_putcmd(const char *str)
{
while (*str)
serial_putchar(*(str++));
}
void serial_clear(void)
{
serial_putcmd(VT100_CLEAR);
}
void serial_start_bold(void)
{
serial_putcmd(VT100_SBOLD);
}
void serial_end_bold(void)
{
serial_putcmd(VT100_EBOLD);
}
void serial_start_reverse(void)
{
serial_putcmd(VT100_SREVERSE);
}
void serial_end_reverse(void)
{
serial_putcmd(VT100_EREVERSE);
}
void serial_start_altcharset(void)
{
serial_putcmd(VT100_SMACS);
}
void serial_end_altcharset(void)
{
serial_putcmd(VT100_RMACS);
}
/**
* Set the foreground and background colors on the serial console.
*
* @param fg Foreground color number.
* @param bg Background color number.
*/
void serial_set_color(short fg, short bg)
{
char buffer[32];
snprintf(buffer, sizeof(buffer), VT100_SET_COLOR, fg, bg);
serial_putcmd(buffer);
}
void serial_set_cursor(int y, int x)
{
char buffer[32];
snprintf(buffer, sizeof(buffer), VT100_CURSOR_ADDR, y + 1, x + 1);
serial_putcmd(buffer);
}
void serial_cursor_enable(int state)
{
if (state)
serial_putcmd(VT100_CURSOR_ON);
else
serial_putcmd(VT100_CURSOR_OFF);
}