linux_old1/include/asm-arm/arch-realview/entry-macro.S

75 lines
2.2 KiB
ArmAsm

/*
* include/asm-arm/arch-realview/entry-macro.S
*
* Low-level IRQ helper macros for RealView platforms
*
* 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 <asm/hardware.h>
#include <asm/hardware/gic.h>
.macro disable_fiq
.endm
/*
* The interrupt numbering scheme is defined in the
* interrupt controller spec. To wit:
*
* Interrupts 0-15 are IPI
* 16-28 are reserved
* 29-31 are local. We allow 30 to be used for the watchdog.
* 32-1020 are global
* 1021-1022 are reserved
* 1023 is "spurious" (no interrupt)
*
* For now, we ignore all local interrupts so only return an interrupt if it's
* between 30 and 1020. The test_for_ipi routine below will pick up on IPIs.
*
* A simple read from the controller will tell us the number of the highest
* priority enabled interrupt. We then just need to check whether it is in the
* valid range for an IRQ (30-1020 inclusive).
*/
.macro get_irqnr_and_base, irqnr, irqstat, base, tmp
ldr \base, =IO_ADDRESS(REALVIEW_GIC_CPU_BASE)
ldr \irqstat, [\base, #GIC_CPU_INTACK] /* bits 12-10 = src CPU, 9-0 = int # */
ldr \tmp, =1021
bic \irqnr, \irqstat, #0x1c00
cmp \irqnr, #29
cmpcc \irqnr, \irqnr
cmpne \irqnr, \tmp
cmpcs \irqnr, \irqnr
.endm
/* We assume that irqstat (the raw value of the IRQ acknowledge
* register) is preserved from the macro above.
* If there is an IPI, we immediately signal end of interrupt on the
* controller, since this requires the original irqstat value which
* we won't easily be able to recreate later.
*/
.macro test_for_ipi, irqnr, irqstat, base, tmp
bic \irqnr, \irqstat, #0x1c00
cmp \irqnr, #16
strcc \irqstat, [\base, #GIC_CPU_EOI]
cmpcs \irqnr, \irqnr
.endm
/* As above, this assumes that irqstat and base are preserved.. */
.macro test_for_ltirq, irqnr, irqstat, base, tmp
bic \irqnr, \irqstat, #0x1c00
mov \tmp, #0
cmp \irqnr, #29
moveq \tmp, #1
streq \irqstat, [\base, #GIC_CPU_EOI]
cmp \tmp, #0
.endm