coreboot-kgpe-d16/payloads/libpayload/libc/lib.c

177 lines
5.1 KiB
C

/*
*
* Copyright (C) 2008 Uwe Hermann <uwe@hermann-uwe.de>
*
* 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 <assert.h>
#include <libpayload.h>
/*
* Convert a number in BCD format to decimal.
*
* @param b The BCD number.
* @return The given BCD number in decimal format.
*/
int bcd2dec(int b)
{
return ((b >> 4) & 0x0f) * 10 + (b & 0x0f);
}
/*
* Convert a number in decimal format into the BCD format.
*
* @param d The decimal number.
* @return The given decimal number in BCD format.
*/
int dec2bcd(int d)
{
return ((d / 10) << 4) | (d % 10);
}
/**
* Return the absolute value of the specified integer.
*
* @param j The integer of which we want to know the absolute value.
* @return The absolute value of the specified integer.
*/
int abs(int j)
{
return (j >= 0 ? j : -j);
}
long int labs(long int j)
{
return (j >= 0 ? j : -j);
}
long long int llabs(long long int j)
{
return (j >= 0 ? j : -j);
}
/**
* Given a 4-bit value, return the ASCII hex representation of it.
*
* @param b A 4-bit value which shall be converted to ASCII hex.
* @return The ASCII hex representation of the specified 4-bit value.
* Returned hex-characters will always be lower-case (a-f, not A-F).
*/
u8 bin2hex(u8 b)
{
return (b < 10) ? '0' + b : 'a' + (b - 10);
}
/**
* Given an ASCII hex input character, return its integer value.
*
* For example, the input value '6' will be converted to 6, 'a'/'A' will
* be converted to 10, 'f'/'F' will be converted to 15, and so on.
*
* The return value for invalid input characters is 0.
*
* @param h The input byte in ASCII hex format.
* @return The integer value of the specified ASCII hex byte.
*/
u8 hex2bin(u8 h)
{
return (('0' <= h && h <= '9') ? (h - '0') : \
('A' <= h && h <= 'F') ? (h - 'A' + 10) : \
('a' <= h && h <= 'f') ? (h - 'a' + 10) : 0);
}
/**
* Enters HALT state, after printing msg
*
* @param msg message to print
*/
void fatal(const char *msg)
{
fprintf(stderr, "%s",msg);
halt();
}
void exit(int status)
{
printf("exited with status %d\n", status);
halt();
}
int errno;
char *getenv(const char *name)
{
return NULL;
}
/*
* Reads a transfer buffer from 32-bit FIFO registers. fifo_stride is the
* distance in bytes between registers (e.g. pass 4 for a normal array of 32-bit
* registers or 0 to read everything from the same register). fifo_width is
* the amount of bytes read per register (can be 1 through 4).
*/
void buffer_from_fifo32(void *buffer, size_t size, void *fifo,
int fifo_stride, int fifo_width)
{
u8 *p = buffer;
int i, j;
assert(fifo_width > 0 && fifo_width <= sizeof(u32) &&
fifo_stride % sizeof(u32) == 0);
for (i = 0; i < size; i += fifo_width, fifo += fifo_stride) {
u32 val = read32(fifo);
for (j = 0; j < MIN(size - i, fifo_width); j++)
*p++ = (u8)(val >> (j * 8));
}
}
/*
* Version of buffer_to_fifo32() that can prepend a prefix of up to fifo_width
* size to the transfer. This is often useful for protocols where a command word
* precedes the actual payload data. The prefix must be packed in the low-order
* bytes of the 'prefix' u32 parameter and any high-order bytes exceeding prefsz
* must be 0. Note that 'size' counts total bytes written, including 'prefsz'.
*/
void buffer_to_fifo32_prefix(const void *buffer, u32 prefix, int prefsz, size_t size,
void *fifo, int fifo_stride, int fifo_width)
{
const u8 *p = buffer;
int i, j = prefsz;
assert(fifo_width > 0 && fifo_width <= sizeof(u32) &&
fifo_stride % sizeof(u32) == 0 && prefsz <= fifo_width);
uint32_t val = prefix;
for (i = 0; i < size; i += fifo_width, fifo += fifo_stride) {
for (; j < MIN(size - i, fifo_width); j++)
val |= *p++ << (j * 8);
write32(fifo, val);
val = 0;
j = 0;
}
}