u-boot/arch/arm/cpu/armv7/syslib.c

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/*
* (C) Copyright 2008
* Texas Instruments, <www.ti.com>
*
* Richard Woodruff <r-woodruff2@ti.com>
* Syed Mohammed Khasim <khasim@ti.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
/************************************************************
* sdelay() - simple spin loop. Will be constant time as
* its generally used in bypass conditions only. This
* is necessary until timers are accessible.
*
* not inline to increase chances its in cache when called
*************************************************************/
void sdelay(unsigned long loops)
{
__asm__ volatile ("1:\n" "subs %0, %1, #1\n"
"bne 1b":"=r" (loops):"0"(loops));
}
/*****************************************************************
* sr32 - clear & set a value in a bit range for a 32 bit address
*****************************************************************/
void sr32(void *addr, u32 start_bit, u32 num_bits, u32 value)
{
u32 tmp, msk = 0;
msk = 1 << num_bits;
--msk;
tmp = readl((u32)addr) & ~(msk << start_bit);
tmp |= value << start_bit;
writel(tmp, (u32)addr);
}
/*********************************************************************
* wait_on_value() - common routine to allow waiting for changes in
* volatile regs.
*********************************************************************/
u32 wait_on_value(u32 read_bit_mask, u32 match_value, void *read_addr,
u32 bound)
{
u32 i = 0, val;
do {
++i;
val = readl((u32)read_addr) & read_bit_mask;
if (val == match_value)
return 1;
if (i == bound)
return 0;
} while (1);
}