linux/arch/arm/mach-spear6xx/include/mach/entry-macro.S

56 lines
1.5 KiB
ArmAsm

/*
* arch/arm/mach-spear6xx/include/mach/entry-macro.S
*
* Low-level IRQ helper macros for SPEAr6xx machine family
*
* Copyright (C) 2009 ST Microelectronics
* Rajeev Kumar<rajeev-dlh.kumar@st.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <mach/hardware.h>
#include <mach/spear.h>
#include <asm/hardware/vic.h>
.macro disable_fiq
.endm
.macro get_irqnr_preamble, base, tmp
.endm
.macro arch_ret_to_user, tmp1, tmp2
.endm
.macro get_irqnr_and_base, irqnr, irqstat, base, tmp
ldr \base, =VA_SPEAR6XX_CPU_VIC_PRI_BASE
ldr \irqstat, [\base, #VIC_IRQ_STATUS] @ get status
mov \irqnr, #0
teq \irqstat, #0
bne 1001f
ldr \base, =VA_SPEAR6XX_CPU_VIC_SEC_BASE
ldr \irqstat, [\base, #VIC_IRQ_STATUS] @ get status
teq \irqstat, #0
beq 1002f @ this will set/reset
@ zero register
mov \irqnr, #32
1001:
/*
* Following code will find bit position of least significang
* bit set in irqstat, using following equation
* least significant bit set in n = (n & ~(n-1))
*/
sub \tmp, \irqstat, #1 @ tmp = irqstat - 1
mvn \tmp, \tmp @ tmp = ~tmp
and \irqstat, \irqstat, \tmp @ irqstat &= tmp
/* Now, irqstat is = bit no. of 1st bit set in vic irq status */
clz \tmp, \irqstat @ tmp = leading zeros
rsb \tmp, \tmp, #0x1F @ tmp = 32 - tmp - 1
add \irqnr, \irqnr, \tmp
1002: /* EQ will be set if no irqs pending */
.endm