linux/arch/arm/mach-omap1/sram.S
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

59 lines
1.4 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/plat-omap/sram-fn.S
*
* Functions that need to be run in internal SRAM
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <mach/hardware.h>
#include "iomap.h"
.text
/*
* Reprograms ULPD and CKCTL.
*/
.align 3
ENTRY(omap1_sram_reprogram_clock)
stmfd sp!, {r0 - r12, lr} @ save registers on stack
mov r2, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0xff000000
orr r2, r2, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0x00ff0000
orr r2, r2, #OMAP1_IO_ADDRESS(DPLL_CTL) & 0x0000ff00
mov r3, #OMAP1_IO_ADDRESS(ARM_CKCTL) & 0xff000000
orr r3, r3, #OMAP1_IO_ADDRESS(ARM_CKCTL) & 0x00ff0000
orr r3, r3, #OMAP1_IO_ADDRESS(ARM_CKCTL) & 0x0000ff00
tst r0, #1 << 4 @ want lock mode?
beq newck @ nope
bic r0, r0, #1 << 4 @ else clear lock bit
strh r0, [r2] @ set dpll into bypass mode
orr r0, r0, #1 << 4 @ set lock bit again
newck:
strh r1, [r3] @ write new ckctl value
strh r0, [r2] @ write new dpll value
mov r4, #0x0700 @ let the clocks settle
orr r4, r4, #0x00ff
delay: sub r4, r4, #1
cmp r4, #0
bne delay
lock: ldrh r4, [r2], #0 @ read back dpll value
tst r0, #1 << 4 @ want lock mode?
beq out @ nope
tst r4, #1 << 0 @ dpll rate locked?
beq lock @ try again
out:
ldmfd sp!, {r0 - r12, pc} @ restore regs and return
ENTRY(omap1_sram_reprogram_clock_sz)
.word . - omap1_sram_reprogram_clock