linux/arch/powerpc/boot/mpc8xx.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

79 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* MPC8xx support functions
*
* Author: Scott Wood <scottwood@freescale.com>
*
* Copyright (c) 2007 Freescale Semiconductor, Inc.
*/
#include "ops.h"
#include "types.h"
#include "fsl-soc.h"
#include "mpc8xx.h"
#include "stdio.h"
#include "io.h"
#define MPC8XX_PLPRCR (0x284/4) /* PLL and Reset Control Register */
/* Return system clock from crystal frequency */
u32 mpc885_get_clock(u32 crystal)
{
u32 *immr;
u32 plprcr;
int mfi, mfn, mfd, pdf;
u32 ret;
immr = fsl_get_immr();
if (!immr) {
printf("mpc885_get_clock: Couldn't get IMMR base.\r\n");
return 0;
}
plprcr = in_be32(&immr[MPC8XX_PLPRCR]);
mfi = (plprcr >> 16) & 15;
if (mfi < 5) {
printf("Warning: PLPRCR[MFI] value of %d out-of-bounds\r\n",
mfi);
mfi = 5;
}
pdf = (plprcr >> 1) & 0xf;
mfd = (plprcr >> 22) & 0x1f;
mfn = (plprcr >> 27) & 0x1f;
ret = crystal * mfi;
if (mfn != 0)
ret += crystal * mfn / (mfd + 1);
return ret / (pdf + 1);
}
/* Set common device tree fields based on the given clock frequencies. */
void mpc8xx_set_clocks(u32 sysclk)
{
void *node;
dt_fixup_cpu_clocks(sysclk, sysclk / 16, sysclk);
node = finddevice("/soc/cpm");
if (node)
setprop(node, "clock-frequency", &sysclk, 4);
node = finddevice("/soc/cpm/brg");
if (node)
setprop(node, "clock-frequency", &sysclk, 4);
}
int mpc885_fixup_clocks(u32 crystal)
{
u32 sysclk = mpc885_get_clock(crystal);
if (!sysclk)
return 0;
mpc8xx_set_clocks(sysclk);
return 1;
}