aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/sni/int-handler.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/sni/int-handler.S')
-rw-r--r--arch/mips/sni/int-handler.S106
1 files changed, 106 insertions, 0 deletions
diff --git a/arch/mips/sni/int-handler.S b/arch/mips/sni/int-handler.S
new file mode 100644
index 00000000000..2cdc09f55f1
--- /dev/null
+++ b/arch/mips/sni/int-handler.S
@@ -0,0 +1,106 @@
+/*
+ * SNI RM200 PCI specific interrupt handler code.
+ *
+ * Copyright (C) 1994, 95, 96, 97, 98, 1999, 2000, 01 by Ralf Baechle
+ */
+#include <asm/asm.h>
+#include <asm/mipsregs.h>
+#include <asm/regdef.h>
+#include <asm/sni.h>
+#include <asm/stackframe.h>
+
+/*
+ * The PCI ASIC has the nasty property that it may delay writes if it is busy.
+ * As a consequence from writes that have not graduated when we exit from the
+ * interrupt handler we might catch a spurious interrupt. To avoid this we
+ * force the PCI ASIC to graduate all writes by executing a read from the
+ * PCI bus.
+ */
+ .set noreorder
+ .set noat
+ .align 5
+ NESTED(sni_rm200_pci_handle_int, PT_SIZE, sp)
+ SAVE_ALL
+ CLI
+ .set at
+
+ /* Blinken light ... */
+ lb t0, led_cache
+ addiu t0, 1
+ sb t0, led_cache
+ sb t0, PCIMT_CSLED # write only register
+ .data
+led_cache: .byte 0
+ .text
+
+ mfc0 t0, CP0_STATUS
+ mfc0 t1, CP0_CAUSE
+ and t0, t1
+
+ andi t1, t0, 0x0800 # hardware interrupt 1
+ bnez t1, _hwint1
+ andi t1, t0, 0x4000 # hardware interrupt 4
+ bnez t1, _hwint4
+ andi t1, t0, 0x2000 # hardware interrupt 3
+ bnez t1, _hwint3
+ andi t1, t0, 0x1000 # hardware interrupt 2
+ bnez t1, _hwint2
+ andi t1, t0, 0x8000 # hardware interrupt 5
+ bnez t1, _hwint5
+ andi t1, t0, 0x0400 # hardware interrupt 0
+ bnez t1, _hwint0
+ nop
+
+ j restore_all # spurious interrupt
+ nop
+
+ ##############################################################################
+
+/* hwint0 should deal with MP agent, ASIC PCI, EISA NMI and debug
+ button interrupts. */
+_hwint0: jal pciasic_hwint0
+ move a0, sp
+ j ret_from_irq
+ nop
+
+/*
+ * hwint 1 deals with EISA and SCSI interrupts
+ */
+_hwint1: jal pciasic_hwint1
+ move a0, sp
+ j ret_from_irq
+ nop
+
+
+/*
+ * This interrupt was used for the com1 console on the first prototypes;
+ * it's unsed otherwise
+ */
+_hwint2: jal pciasic_hwint2
+ move a0, sp
+ j ret_from_irq
+ nop
+
+/*
+ * hwint 3 are the PCI interrupts A - D
+ */
+_hwint3: jal pciasic_hwint3
+ move a0, sp
+ j ret_from_irq
+ nop
+
+/*
+ * hwint 4 is used for only the onboard PCnet 32.
+ */
+_hwint4: jal pciasic_hwint4
+ move a0, sp
+ j ret_from_irq
+ nop
+
+/* hwint5 is the r4k count / compare interrupt */
+_hwint5: jal pciasic_hwint5
+ move a0, sp
+ j ret_from_irq
+ nop
+
+ END(sni_rm200_pci_handle_int)