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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/mips/vr4181/common/int_handler.S
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/mips/vr4181/common/int_handler.S')
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1 files changed, 206 insertions, 0 deletions
diff --git a/arch/mips/vr4181/common/int_handler.S b/arch/mips/vr4181/common/int_handler.S
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+/*
+ * arch/mips/vr4181/common/int_handler.S
+ *
+ * Adapted to the VR4181 and almost entirely rewritten:
+ * Copyright (C) 1999 Bradley D. LaRonde and Michael Klar
+ *
+ * Clean up to conform to the new IRQ
+ * Copyright (C) 2001 MontaVista Software Inc.
+ * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ */
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+#include <asm/stackframe.h>
+
+#include <asm/vr4181/vr4181.h>
+
+/*
+ * [jsun]
+ * See include/asm/vr4181/irq.h for IRQ assignment and strategy.
+ */
+
+ .text
+ .set noreorder
+
+ .align 5
+ NESTED(vr4181_handle_irq, PT_SIZE, ra)
+
+ .set noat
+ SAVE_ALL
+ CLI
+
+ .set at
+ .set noreorder
+
+ mfc0 t0, CP0_CAUSE
+ mfc0 t2, CP0_STATUS
+
+ and t0, t2
+
+ /* we check IP3 first; it happens most frequently */
+ andi t1, t0, STATUSF_IP3
+ bnez t1, ll_cpu_ip3
+ andi t1, t0, STATUSF_IP2
+ bnez t1, ll_cpu_ip2
+ andi t1, t0, STATUSF_IP7 /* cpu timer */
+ bnez t1, ll_cputimer_irq
+ andi t1, t0, STATUSF_IP4
+ bnez t1, ll_cpu_ip4
+ andi t1, t0, STATUSF_IP5
+ bnez t1, ll_cpu_ip5
+ andi t1, t0, STATUSF_IP6
+ bnez t1, ll_cpu_ip6
+ andi t1, t0, STATUSF_IP0 /* software int 0 */
+ bnez t1, ll_cpu_ip0
+ andi t1, t0, STATUSF_IP1 /* software int 1 */
+ bnez t1, ll_cpu_ip1
+ nop
+
+ .set reorder
+do_spurious:
+ j spurious_interrupt
+
+/*
+ * regular CPU irqs
+ */
+ll_cputimer_irq:
+ li a0, VR4181_IRQ_TIMER
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+
+ll_cpu_ip0:
+ li a0, VR4181_IRQ_SW1
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+ll_cpu_ip1:
+ li a0, VR4181_IRQ_SW2
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+ll_cpu_ip3:
+ li a0, VR4181_IRQ_INT1
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+ll_cpu_ip4:
+ li a0, VR4181_IRQ_INT2
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+ll_cpu_ip5:
+ li a0, VR4181_IRQ_INT3
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+ll_cpu_ip6:
+ li a0, VR4181_IRQ_INT4
+ move a1, sp
+ jal do_IRQ
+ j ret_from_irq
+
+/*
+ * One of the sys irq has happend.
+ *
+ * In the interest of speed, we first determine in the following order
+ * which 16-irq block have pending interrupts:
+ * sysint1 (16 sources, including cascading intrs from GPIO)
+ * sysint2
+ * gpio (16 intr sources)
+ *
+ * Then we do binary search to find the exact interrupt source.
+ */
+ll_cpu_ip2:
+
+ lui t3,%hi(VR4181_SYSINT1REG)
+ lhu t0,%lo(VR4181_SYSINT1REG)(t3)
+ lhu t2,%lo(VR4181_MSYSINT1REG)(t3)
+ and t0, 0xfffb /* hack - remove RTC Long 1 intr */
+ and t0, t2
+ beqz t0, check_sysint2
+
+ /* check for GPIO interrupts */
+ andi t1, t0, 0x0100
+ bnez t1, check_gpio_int
+
+ /* so we have an interrupt in sysint1 which is not gpio int */
+ li a0, VR4181_SYS_IRQ_BASE - 1
+ j check_16
+
+check_sysint2:
+
+ lhu t0,%lo(VR4181_SYSINT2REG)(t3)
+ lhu t2,%lo(VR4181_MSYSINT2REG)(t3)
+ and t0, 0xfffe /* hack - remove RTC Long 2 intr */
+ and t0, t2
+ li a0, VR4181_SYS_IRQ_BASE + 16 - 1
+ j check_16
+
+check_gpio_int:
+ lui t3,%hi(VR4181_GPINTMSK)
+ lhu t0,%lo(VR4181_GPINTMSK)(t3)
+ lhu t2,%lo(VR4181_GPINTSTAT)(t3)
+ xori t0, 0xffff /* why? reverse logic? */
+ and t0, t2
+ li a0, VR4181_GPIO_IRQ_BASE - 1
+ j check_16
+
+/*
+ * When we reach check_16, we have 16-bit status in t0 and base irq number
+ * in a0.
+ */
+check_16:
+ andi t1, t0, 0xff
+ bnez t1, check_8
+
+ srl t0, 8
+ addi a0, 8
+ j check_8
+
+/*
+ * When we reach check_8, we have 8-bit status in t0 and base irq number
+ * in a0.
+ */
+check_8:
+ andi t1, t0, 0xf
+ bnez t1, check_4
+
+ srl t0, 4
+ addi a0, 4
+ j check_4
+
+/*
+ * When we reach check_4, we have 4-bit status in t0 and base irq number
+ * in a0.
+ */
+check_4:
+ andi t0, t0, 0xf
+ beqz t0, do_spurious
+
+loop:
+ andi t2, t0, 0x1
+ srl t0, 1
+ addi a0, 1
+ beqz t2, loop
+
+found_it:
+ move a1, sp
+ jal do_IRQ
+
+ j ret_from_irq
+
+ END(vr4181_handle_irq)