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Diffstat (limited to 'arch/ppc/syslib/ppc8xx_pic.c')
-rw-r--r--arch/ppc/syslib/ppc8xx_pic.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/ppc/syslib/ppc8xx_pic.c b/arch/ppc/syslib/ppc8xx_pic.c
new file mode 100644
index 000000000000..d3b01c6c97de
--- /dev/null
+++ b/arch/ppc/syslib/ppc8xx_pic.c
@@ -0,0 +1,130 @@
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/interrupt.h>
+#include <asm/irq.h>
+#include <asm/8xx_immap.h>
+#include <asm/mpc8xx.h>
+#include "ppc8xx_pic.h"
+
+extern int cpm_get_irq(struct pt_regs *regs);
+
+/* The 8xx internal interrupt controller. It is usually
+ * the only interrupt controller. Some boards, like the MBX and
+ * Sandpoint have the 8259 as a secondary controller. Depending
+ * upon the processor type, the internal controller can have as
+ * few as 16 interrups or as many as 64. We could use the
+ * "clear_bit()" and "set_bit()" functions like other platforms,
+ * but they are overkill for us.
+ */
+
+static void m8xx_mask_irq(unsigned int irq_nr)
+{
+ int bit, word;
+
+ bit = irq_nr & 0x1f;
+ word = irq_nr >> 5;
+
+ ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
+ ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
+ ppc_cached_irq_mask[word];
+}
+
+static void m8xx_unmask_irq(unsigned int irq_nr)
+{
+ int bit, word;
+
+ bit = irq_nr & 0x1f;
+ word = irq_nr >> 5;
+
+ ppc_cached_irq_mask[word] |= (1 << (31-bit));
+ ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
+ ppc_cached_irq_mask[word];
+}
+
+static void m8xx_end_irq(unsigned int irq_nr)
+{
+ if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS))
+ && irq_desc[irq_nr].action) {
+ int bit, word;
+
+ bit = irq_nr & 0x1f;
+ word = irq_nr >> 5;
+
+ ppc_cached_irq_mask[word] |= (1 << (31-bit));
+ ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
+ ppc_cached_irq_mask[word];
+ }
+}
+
+
+static void m8xx_mask_and_ack(unsigned int irq_nr)
+{
+ int bit, word;
+
+ bit = irq_nr & 0x1f;
+ word = irq_nr >> 5;
+
+ ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
+ ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
+ ppc_cached_irq_mask[word];
+ ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sipend = 1 << (31-bit);
+}
+
+struct hw_interrupt_type ppc8xx_pic = {
+ .typename = " 8xx SIU ",
+ .enable = m8xx_unmask_irq,
+ .disable = m8xx_mask_irq,
+ .ack = m8xx_mask_and_ack,
+ .end = m8xx_end_irq,
+};
+
+/*
+ * We either return a valid interrupt or -1 if there is nothing pending
+ */
+int
+m8xx_get_irq(struct pt_regs *regs)
+{
+ int irq;
+
+ /* For MPC8xx, read the SIVEC register and shift the bits down
+ * to get the irq number.
+ */
+ irq = ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sivec >> 26;
+
+ /*
+ * When we read the sivec without an interrupt to process, we will
+ * get back SIU_LEVEL7. In this case, return -1
+ */
+ if (irq == CPM_INTERRUPT)
+ irq = CPM_IRQ_OFFSET + cpm_get_irq(regs);
+#if defined(CONFIG_PCI)
+ else if (irq == ISA_BRIDGE_INT) {
+ int isa_irq;
+
+ if ((isa_irq = i8259_poll(regs)) >= 0)
+ irq = I8259_IRQ_OFFSET + isa_irq;
+ }
+#endif /* CONFIG_PCI */
+ else if (irq == SIU_LEVEL7)
+ irq = -1;
+
+ return irq;
+}
+
+#if defined(CONFIG_MBX) && defined(CONFIG_PCI)
+/* Only the MBX uses the external 8259. This allows us to catch standard
+ * drivers that may mess up the internal interrupt controllers, and also
+ * allow them to run without modification on the MBX.
+ */
+void mbx_i8259_action(int irq, void *dev_id, struct pt_regs *regs)
+{
+ /* This interrupt handler never actually gets called. It is
+ * installed only to unmask the 8259 cascade interrupt in the SIU
+ * and to make the 8259 cascade interrupt visible in /proc/interrupts.
+ */
+}
+#endif /* CONFIG_PCI */