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Diffstat (limited to 'arch/ppc/syslib/cpm2_pic.c')
-rw-r--r--arch/ppc/syslib/cpm2_pic.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/ppc/syslib/cpm2_pic.c b/arch/ppc/syslib/cpm2_pic.c
new file mode 100644
index 00000000000..954b07fc1df
--- /dev/null
+++ b/arch/ppc/syslib/cpm2_pic.c
@@ -0,0 +1,172 @@
+/* The CPM2 internal interrupt controller. It is usually
+ * the only interrupt controller.
+ * There are two 32-bit registers (high/low) for up to 64
+ * possible interrupts.
+ *
+ * Now, the fun starts.....Interrupt Numbers DO NOT MAP
+ * in a simple arithmetic fashion to mask or pending registers.
+ * That is, interrupt 4 does not map to bit position 4.
+ * We create two tables, indexed by vector number, to indicate
+ * which register to use and which bit in the register to use.
+ */
+
+#include <linux/stddef.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/irq.h>
+
+#include <asm/immap_cpm2.h>
+#include <asm/mpc8260.h>
+
+#include "cpm2_pic.h"
+
+static u_char irq_to_siureg[] = {
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+/* bit numbers do not match the docs, these are precomputed so the bit for
+ * a given irq is (1 << irq_to_siubit[irq]) */
+static u_char irq_to_siubit[] = {
+ 0, 15, 14, 13, 12, 11, 10, 9,
+ 8, 7, 6, 5, 4, 3, 2, 1,
+ 2, 1, 15, 14, 13, 12, 11, 10,
+ 9, 8, 7, 6, 5, 4, 3, 0,
+ 31, 30, 29, 28, 27, 26, 25, 24,
+ 23, 22, 21, 20, 19, 18, 17, 16,
+ 16, 17, 18, 19, 20, 21, 22, 23,
+ 24, 25, 26, 27, 28, 29, 30, 31,
+};
+
+static void cpm2_mask_irq(unsigned int irq_nr)
+{
+ int bit, word;
+ volatile uint *simr;
+
+ irq_nr -= CPM_IRQ_OFFSET;
+
+ bit = irq_to_siubit[irq_nr];
+ word = irq_to_siureg[irq_nr];
+
+ simr = &(cpm2_immr->im_intctl.ic_simrh);
+ ppc_cached_irq_mask[word] &= ~(1 << bit);
+ simr[word] = ppc_cached_irq_mask[word];
+}
+
+static void cpm2_unmask_irq(unsigned int irq_nr)
+{
+ int bit, word;
+ volatile uint *simr;
+
+ irq_nr -= CPM_IRQ_OFFSET;
+
+ bit = irq_to_siubit[irq_nr];
+ word = irq_to_siureg[irq_nr];
+
+ simr = &(cpm2_immr->im_intctl.ic_simrh);
+ ppc_cached_irq_mask[word] |= 1 << bit;
+ simr[word] = ppc_cached_irq_mask[word];
+}
+
+static void cpm2_mask_and_ack(unsigned int irq_nr)
+{
+ int bit, word;
+ volatile uint *simr, *sipnr;
+
+ irq_nr -= CPM_IRQ_OFFSET;
+
+ bit = irq_to_siubit[irq_nr];
+ word = irq_to_siureg[irq_nr];
+
+ simr = &(cpm2_immr->im_intctl.ic_simrh);
+ sipnr = &(cpm2_immr->im_intctl.ic_sipnrh);
+ ppc_cached_irq_mask[word] &= ~(1 << bit);
+ simr[word] = ppc_cached_irq_mask[word];
+ sipnr[word] = 1 << bit;
+}
+
+static void cpm2_end_irq(unsigned int irq_nr)
+{
+ int bit, word;
+ volatile uint *simr;
+
+ if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS))
+ && irq_desc[irq_nr].action) {
+
+ irq_nr -= CPM_IRQ_OFFSET;
+ bit = irq_to_siubit[irq_nr];
+ word = irq_to_siureg[irq_nr];
+
+ simr = &(cpm2_immr->im_intctl.ic_simrh);
+ ppc_cached_irq_mask[word] |= 1 << bit;
+ simr[word] = ppc_cached_irq_mask[word];
+ }
+}
+
+static struct hw_interrupt_type cpm2_pic = {
+ .typename = " CPM2 SIU ",
+ .enable = cpm2_unmask_irq,
+ .disable = cpm2_mask_irq,
+ .ack = cpm2_mask_and_ack,
+ .end = cpm2_end_irq,
+};
+
+int cpm2_get_irq(struct pt_regs *regs)
+{
+ int irq;
+ unsigned long bits;
+
+ /* For CPM2, read the SIVEC register and shift the bits down
+ * to get the irq number. */
+ bits = cpm2_immr->im_intctl.ic_sivec;
+ irq = bits >> 26;
+
+ if (irq == 0)
+ return(-1);
+ return irq+CPM_IRQ_OFFSET;
+}
+
+void cpm2_init_IRQ(void)
+{
+ int i;
+
+ /* Clear the CPM IRQ controller, in case it has any bits set
+ * from the bootloader
+ */
+
+ /* Mask out everything */
+ cpm2_immr->im_intctl.ic_simrh = 0x00000000;
+ cpm2_immr->im_intctl.ic_simrl = 0x00000000;
+ wmb();
+
+ /* Ack everything */
+ cpm2_immr->im_intctl.ic_sipnrh = 0xffffffff;
+ cpm2_immr->im_intctl.ic_sipnrl = 0xffffffff;
+ wmb();
+
+ /* Dummy read of the vector */
+ i = cpm2_immr->im_intctl.ic_sivec;
+ rmb();
+
+ /* Initialize the default interrupt mapping priorities,
+ * in case the boot rom changed something on us.
+ */
+ cpm2_immr->im_intctl.ic_sicr = 0;
+ cpm2_immr->im_intctl.ic_scprrh = 0x05309770;
+ cpm2_immr->im_intctl.ic_scprrl = 0x05309770;
+
+
+ /* Enable chaining to OpenPIC, and make everything level
+ */
+ for (i = 0; i < NR_CPM_INTS; i++) {
+ irq_desc[i+CPM_IRQ_OFFSET].handler = &cpm2_pic;
+ irq_desc[i+CPM_IRQ_OFFSET].status |= IRQ_LEVEL;
+ }
+}