linux/include/asm-arm/arch-ixp4xx/entry-macro.S
Kenneth Tan 251b928cdf [ARM] 3021/1: Interrupt 0 bug fix for ixp4xx
Patch from Kenneth Tan

The get_irqnr_and_base subroutine of ixp4xx does not take interrupt 0 condition into account properly. We should not perform "subs" here. The Z flag will be set when interrupt 0 occur, which resulting "movne r1, sp" in the caller routine (irq_handler) not being executed.

When interrupt 0 occur:
o if CONFIG_CPU_IXP46X is not set, "subs" will set the Z flag and return
o if CONFIG_CPU_IXP46X is set, codes in upper interrupt handling will be trigerred. But since this is not supper interrupt, the "cmp" in the upper interrupt handling portion will set the Z flag and return

Signed-off-by: Kenneth Tan <chong.yin.tan@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-18 07:53:35 +01:00

41 lines
996 B
ArmAsm

/*
* include/asm-arm/arch-ixp4xx/entry-macro.S
*
* Low-level IRQ helper macros for IXP4xx-based 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.
*/
.macro disable_fiq
.endm
.macro get_irqnr_and_base, irqnr, irqstat, base, tmp
ldr \irqstat, =(IXP4XX_INTC_BASE_VIRT+IXP4XX_ICIP_OFFSET)
ldr \irqstat, [\irqstat] @ get interrupts
cmp \irqstat, #0
beq 1001f @ upper IRQ?
clz \irqnr, \irqstat
mov \base, #31
sub \irqnr, \base, \irqnr
b 1002f @ lower IRQ being
@ handled
1001:
/*
* IXP465 has an upper IRQ status register
*/
#if defined(CONFIG_CPU_IXP46X)
ldr \irqstat, =(IXP4XX_INTC_BASE_VIRT+IXP4XX_ICIP2_OFFSET)
ldr \irqstat, [\irqstat] @ get upper interrupts
mov \irqnr, #63
clz \irqstat, \irqstat
cmp \irqstat, #32
subne \irqnr, \irqnr, \irqstat
#endif
1002:
.endm