diff options
Diffstat (limited to 'arch/powerpc/cpu/mpc8xx/interrupts.c')
-rw-r--r-- | arch/powerpc/cpu/mpc8xx/interrupts.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/mpc8xx/interrupts.c b/arch/powerpc/cpu/mpc8xx/interrupts.c new file mode 100644 index 0000000000..5daa6b2752 --- /dev/null +++ b/arch/powerpc/cpu/mpc8xx/interrupts.c @@ -0,0 +1,294 @@ +/* + * (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; +} + +/************************************************************************/ |