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-rw-r--r--arch/powerpc/cpu/mpc8xx/interrupts.c294
1 files changed, 294 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/mpc8xx/interrupts.c b/arch/powerpc/cpu/mpc8xx/interrupts.c
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+++ b/arch/powerpc/cpu/mpc8xx/interrupts.c
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+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <mpc8xx.h>
+#include <mpc8xx_irq.h>
+#include <asm/processor.h>
+#include <commproc.h>
+
+/************************************************************************/
+
+/*
+ * CPM interrupt vector functions.
+ */
+struct interrupt_action {
+ interrupt_handler_t *handler;
+ void *arg;
+};
+
+static struct interrupt_action cpm_vecs[CPMVEC_NR];
+static struct interrupt_action irq_vecs[NR_IRQS];
+
+static void cpm_interrupt_init (void);
+static void cpm_interrupt (void *regs);
+
+/************************************************************************/
+
+int interrupt_init_cpu (unsigned *decrementer_count)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+
+ *decrementer_count = get_tbclk () / CONFIG_SYS_HZ;
+
+ /* disable all interrupts */
+ immr->im_siu_conf.sc_simask = 0;
+
+ /* Configure CPM interrupts */
+ cpm_interrupt_init ();
+
+ return (0);
+}
+
+/************************************************************************/
+
+/*
+ * Handle external interrupts
+ */
+void external_interrupt (struct pt_regs *regs)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+ int irq;
+ ulong simask, newmask;
+ ulong vec, v_bit;
+
+ /*
+ * read the SIVEC register and shift the bits down
+ * to get the irq number
+ */
+ vec = immr->im_siu_conf.sc_sivec;
+ irq = vec >> 26;
+ v_bit = 0x80000000UL >> irq;
+
+ /*
+ * Read Interrupt Mask Register and Mask Interrupts
+ */
+ simask = immr->im_siu_conf.sc_simask;
+ newmask = simask & (~(0xFFFF0000 >> irq));
+ immr->im_siu_conf.sc_simask = newmask;
+
+ if (!(irq & 0x1)) { /* External Interrupt ? */
+ ulong siel;
+
+ /*
+ * Read Interrupt Edge/Level Register
+ */
+ siel = immr->im_siu_conf.sc_siel;
+
+ if (siel & v_bit) { /* edge triggered interrupt ? */
+ /*
+ * Rewrite SIPEND Register to clear interrupt
+ */
+ immr->im_siu_conf.sc_sipend = v_bit;
+ }
+ }
+
+ if (irq_vecs[irq].handler != NULL) {
+ irq_vecs[irq].handler (irq_vecs[irq].arg);
+ } else {
+ printf ("\nBogus External Interrupt IRQ %d Vector %ld\n",
+ irq, vec);
+ /* turn off the bogus interrupt to avoid it from now */
+ simask &= ~v_bit;
+ }
+ /*
+ * Re-Enable old Interrupt Mask
+ */
+ immr->im_siu_conf.sc_simask = simask;
+}
+
+/************************************************************************/
+
+/*
+ * CPM interrupt handler
+ */
+static void cpm_interrupt (void *regs)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+ uint vec;
+
+ /*
+ * Get the vector by setting the ACK bit
+ * and then reading the register.
+ */
+ immr->im_cpic.cpic_civr = 1;
+ vec = immr->im_cpic.cpic_civr;
+ vec >>= 11;
+
+ if (cpm_vecs[vec].handler != NULL) {
+ (*cpm_vecs[vec].handler) (cpm_vecs[vec].arg);
+ } else {
+ immr->im_cpic.cpic_cimr &= ~(1 << vec);
+ printf ("Masking bogus CPM interrupt vector 0x%x\n", vec);
+ }
+ /*
+ * After servicing the interrupt,
+ * we have to remove the status indicator.
+ */
+ immr->im_cpic.cpic_cisr |= (1 << vec);
+}
+
+/*
+ * The CPM can generate the error interrupt when there is a race
+ * condition between generating and masking interrupts. All we have
+ * to do is ACK it and return. This is a no-op function so we don't
+ * need any special tests in the interrupt handler.
+ */
+static void cpm_error_interrupt (void *dummy)
+{
+}
+
+/************************************************************************/
+/*
+ * Install and free an interrupt handler
+ */
+void irq_install_handler (int vec, interrupt_handler_t * handler,
+ void *arg)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+
+ if ((vec & CPMVEC_OFFSET) != 0) {
+ /* CPM interrupt */
+ vec &= 0xffff;
+ if (cpm_vecs[vec].handler != NULL) {
+ printf ("CPM interrupt 0x%x replacing 0x%x\n",
+ (uint) handler,
+ (uint) cpm_vecs[vec].handler);
+ }
+ cpm_vecs[vec].handler = handler;
+ cpm_vecs[vec].arg = arg;
+ immr->im_cpic.cpic_cimr |= (1 << vec);
+#if 0
+ printf ("Install CPM interrupt for vector %d ==> %p\n",
+ vec, handler);
+#endif
+ } else {
+ /* SIU interrupt */
+ if (irq_vecs[vec].handler != NULL) {
+ printf ("SIU interrupt %d 0x%x replacing 0x%x\n",
+ vec,
+ (uint) handler,
+ (uint) cpm_vecs[vec].handler);
+ }
+ irq_vecs[vec].handler = handler;
+ irq_vecs[vec].arg = arg;
+ immr->im_siu_conf.sc_simask |= 1 << (31 - vec);
+#if 0
+ printf ("Install SIU interrupt for vector %d ==> %p\n",
+ vec, handler);
+#endif
+ }
+}
+
+void irq_free_handler (int vec)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+
+ if ((vec & CPMVEC_OFFSET) != 0) {
+ /* CPM interrupt */
+ vec &= 0xffff;
+#if 0
+ printf ("Free CPM interrupt for vector %d ==> %p\n",
+ vec, cpm_vecs[vec].handler);
+#endif
+ immr->im_cpic.cpic_cimr &= ~(1 << vec);
+ cpm_vecs[vec].handler = NULL;
+ cpm_vecs[vec].arg = NULL;
+ } else {
+ /* SIU interrupt */
+#if 0
+ printf ("Free CPM interrupt for vector %d ==> %p\n",
+ vec, cpm_vecs[vec].handler);
+#endif
+ immr->im_siu_conf.sc_simask &= ~(1 << (31 - vec));
+ irq_vecs[vec].handler = NULL;
+ irq_vecs[vec].arg = NULL;
+ }
+}
+
+/************************************************************************/
+
+static void cpm_interrupt_init (void)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+
+ /*
+ * Initialize the CPM interrupt controller.
+ */
+
+ immr->im_cpic.cpic_cicr =
+ (CICR_SCD_SCC4 |
+ CICR_SCC_SCC3 |
+ CICR_SCB_SCC2 |
+ CICR_SCA_SCC1) | ((CPM_INTERRUPT / 2) << 13) | CICR_HP_MASK;
+
+ immr->im_cpic.cpic_cimr = 0;
+
+ /*
+ * Install the error handler.
+ */
+ irq_install_handler (CPMVEC_ERROR, cpm_error_interrupt, NULL);
+
+ immr->im_cpic.cpic_cicr |= CICR_IEN;
+
+ /*
+ * Install the cpm interrupt handler
+ */
+ irq_install_handler (CPM_INTERRUPT, cpm_interrupt, NULL);
+}
+
+/************************************************************************/
+
+/*
+ * timer_interrupt - gets called when the decrementer overflows,
+ * with interrupts disabled.
+ * Trivial implementation - no need to be really accurate.
+ */
+void timer_interrupt_cpu (struct pt_regs *regs)
+{
+ volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR;
+
+#if 0
+ printf ("*** Timer Interrupt *** ");
+#endif
+ /* Reset Timer Expired and Timers Interrupt Status */
+ immr->im_clkrstk.cark_plprcrk = KAPWR_KEY;
+ __asm__ ("nop");
+ /*
+ Clear TEXPS (and TMIST on older chips). SPLSS (on older
+ chips) is cleared too.
+
+ Bitwise OR is a read-modify-write operation so ALL bits
+ which are cleared by writing `1' would be cleared by
+ operations like
+
+ immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS;
+
+ The same can be achieved by simple writing of the PLPRCR
+ to itself. If a bit value should be preserved, read the
+ register, ZERO the bit and write, not OR, the result back.
+ */
+ immr->im_clkrst.car_plprcr = immr->im_clkrst.car_plprcr;
+}
+
+/************************************************************************/